Assessment of Epiphytic Pathogens from Different Media, Associated with some Ready-for-sale Fresh-Fruits and Vegetables in Selected Markets within Southwest Nigeria

doi:10.21203/rs.3.rs-2758120/v1

This study evaluated microbial safety (incidence, risk levels and prevalence) of fresh produce from three states in 30 open-markets in Southwest, Nigeria. Total Viable Count of Enteriobacteriacaea, coliforms and Listeria (using four broths and five agar) were done on homogenised samples (n = 180). Epiphytes prevalence decrease with cabbage from [Ondo (4.33%), Lagos (3.52%), Osun (2.71)]; carrot [Osun (2.80%), Lagos (2.26%) and Ondo (1.81%)]; cucumber [Ondo (3.52%), Osun (3.25%) and Lagos (2.89%)]; garden egg and tomato [Lagos (4.15% and 3.61%), Osun (2.17% and 2.89%) and Ondo (1.71% and 2.44) respectively]; watermelon and all fresh produce [Lagos (2.98% and 19.40%), Ondo (1.99% and 15.79%) and Osun (1.71% and 15.52) respectively]. PALCAM and XLD agar have highest isolation rate, sensitivity, differential ability and effectiveness but low selectivity. Tomato from Lagos State markets showed 0.00x10⁰ cfu/g on VRBG, BGA and XLD. Fresh produce epiphytes prevalence increased in Lagos from [carrot (2.26%), cucumber (2.89%), watermelon (2.98%), cabbage (3.52%), tomatoes (3.61%) to garden egg (4.15%)]; Osun State [water melon (1.71%), garden egg (2.17%), cabbage (2.71%), carrot (2.80%), tomatoes (2.89%) to cucumber (3.25%)]; in Ondo State [garden egg (1.71%), carrot (1.81%), watermelon (1.99%), tomatoes (2.44%) cucumber (3.52%) to cabbage (4.33%)]. Hence, fresh produce are route of food poisoning.

Food Science & Technology

Epiphytic pathogens

Culturing media

Fruits and Vegetables

Food Safety

Contamination

Embryonic knowledge of the safety of fresh produce in the whole of Southwest, Nigeria cause food-borne disease to persist. However, this requires collating available data about the contamination of pathogenic bacteria in ready-for-sale fresh produce for effective assessment, monitoring and surveiliance to curb the challenge. This will also maintain and ensure one health approach in addressing the public health threat arising from contaminated fruits and vegetables in Nigeria. Besides, sustainable response to this study will help Nigerian market (along side with others involved in the supply chain) to deliver a safe and quality fruits and vegetables.

As a result of the crucial nutritional compositions of fruits and vegetables, daily intake has been encouraged in order to promote human health and satisfy humans medically, most especially amidst the vulnerable group of people. However, enteric bacteria are found to contaminate fruits and vegetables from farm to fork, and this tends to cause life-threatening food-borne illnesses in consumers (Berger et al., 2010). Contamination could also be from the soil, irrigation water, tools and equipment, handlers or marketers (Machado-Moreira et al., 2019; Alegbeleye et al., 2018). This contamination is being quantified by microbial load of pathogens in order to ascertain the level of the safety of such foods.

In Nigeria, only few comprehensive studies on microbial safety of fruits and vegetables exist in specific sub-administrative regions (Adekanle et al., 2015; Ajayeoba et al., 2015; Oluboyo et al., 2019). Imafidor et al. (2018) worked only in Benin City, Edo State, where Pseudomonas spp. and Bacillus spp were found in carrot, guava, oranges, cucumber, garden egg, banana, plantain, cabbage, spinach, and Oha leaves. Orji et al. (2016) assessed Staphylococcus aureus, Salmonella spp., Escherichia coli, Shigella spp. and Pseudomonas spp., with Mucor spp. solely in Abakaliki, Ebonyi. In addition, Staphylococci (CoNS), Escherichia coli and Salmonella dominate the ready-to-eat fruits and vegetables sold only in Benin (Uniben), Edo State, Nigeria (Iyoha and Agoreyo, 2015).

Meanwhile, only few studies shed light on the microbial safety of fresh fruits and vegetables sold in different states conjointly. Ajayeoba et al. (2015) worked on Listeria in Southwestern state of Nigeria fruits and vegetable in 2012–2013. Igbeneghu and Adebayo (2015) also worked on Enterobacter spp. and E. coli in Lettuce from Ile-Ife, Ilorin, and Lagos, western part of Nigeria. Daily increase in the rate of contamination of fruits and vegetables requires frequent data from all locations in order to measure the trend. In the Southwest of Nigeria, most of the fresh produce (fruits and vegetables) are from the Northern part of Nigeria which are sold in the markets..

Microbial contaminant such as enteric pathogenic epiphytes are assessed with the aid of culturing media. Commonly used media for isolation of pathogenic bacteria in Nigeria includes MacConkey agar, Nutrient agar, Salmonella–Shigella agar, Mannitol Salt agar, Blood agar. These media are recommended by Official Methods of Analysis (AOAC). In this study rarely used culturing media as such that used by Public Health England (PHE) reference method are employed, even though they are expensive and not easily accessible in Nigeria. Yet, they are recommended by International Organization for Standardization (ISO). Examples of these media are Xylose lysine Desoxycholate (XLD) Agar; Brilliant Green Agar (modified) (BGA); Violet Red Bile Glucose Agar (VRBG), Brilliant Green Bile Agar (modified) (BGA), Violet Red Bile Glucose Agar (VRBG), Rappaport Vassiliadis Broth (RVB) Half Fraser Broth and Full Fraser Broth, OXFORD Agar and PALCAM Agar. These media with extensive steps and usage of different supplement are utilized in this study.

In this study, these media were used to recover epiphytic pathogens on fruits and vegetables sold in open market in the Southwest Nigeria. Emphasis is on the microbial safety of fruits and vegetables sold in reputable open markets in three of the states (Oyo, Ogun and Osun)o f the Southwestern region of Nigeria. The results were compared with other research works for effective monitoring of potential food-borne illnesses in Nigeria. The recoverying of the microbial harzards (Enterobacteriacae, coliforms and Listeria) were analysed on different media and the effect of these media were assessed. The essence of this was also to gather data on the microbial hazard of fruits and vegetables in the Southwest in order to find means of ensuring quality and safe fruits and vegetables for consumers’ health.

2.1 Samples Collection

Study markets selected were from five administrative zones (Epe, Ikorodu, Lagos and Ikeja) in Lagos State, four in Osun State (Iwo, Ilesha, Ife and Osogbo) and two administrative zones (First order division and Second order division) in Ondo States. Whole samples of cucumber (Cucumis sativas), cabbage (Brassica oleracea), carrot (Daucus carota), tomatoes (Solanum lycopersicum), watermelon (Citrullus lanatus), and garden egg (Solanum melongena) were collected from November, 2021 to February, 2022 in 30 markets (known for the selling of common fresh produce) from Ondo, Osun and Lagos States of the Southwest Nigeria. From the three states, total fresh produce (n = 540) were obtained from three vendors and the same sample from the three vendors in a market were homogenized to make a total of 180 samples altogether. Markets considered are open-market known for the reputable sales from farmers of fruits and vegetables. These samples were transported using a cold box of temperature of 4°C, wrapped with sterile plastic wrap to an approved laboratory (Nigerian Institute of Medical Research, Lagos, Nigeria) and subjected to microbial analysis within 24 h.

2.2 Analytical Methods

2.2.1 Isolation, Enumeration and Detection

The fresh produce (25 g each) collected were analysed for epiphytic bacterial pathogens (majorly Enteriobacteriacae, coliforms and Listeria spp) using Public Health England method (PHE, 2019). Homogenized sample (25g) was put in 225 ml buffered peptone water (primary enrichment) in stomacher bags, shaken vigorously and incubated at 37°C for 18h. Enriched samples with Rappaport-Vassiliadis Soya Broth (RVS, TM 1282) were cultured by both streaking and pour plate methods on Brilliant Green Bile Agar (modified) (FLUMEDIA, HF016) and Xylose lysine Desoxycholate (XLD) Agar (TM492) by ISO 6579:2002 + A1: 2007; Enriched samples with Peptone water (HIMEDIA, M028S-500G, India) was also cultured on Violet Red Bile Glucose Agar (VRBG, TM MEDIA, India) using ISO 21528:2017; as well as enriched samples with Half and Full- Fraser Broth (OXOID, CM0895 ISO, United Kingdom) were as well cultured by both streaking and pour plate method on Listeria Selective Agar Base (Oxford Formulation. CM0856) and PALCAM Agar (Oxoid, CM0877) using ISO 11290-1:1996 + A1:2004, BS 5763-18:1997, ISO 11290-2:1998.

Colonies from pour plate were counted and isolates from plates were sub-cultured by streaking, purified as well as stored at 4°C in nutrient broth in the presence of 20% glycerol. Long term preservation was done in 15–80% glycerol in Cryotube™ vials and stored at -20°C. The food samples were classified as satisfactory/acceptable, borderline, and unsatisfactory/unacceptable according to national microbiological guidelines (Standards Organisation of Nigeria; Food Standards Agency). Biochemical tests (catalase, oxidase and Gram’s staining tests were done). Microbact Listeria 12L Identification System (MB11B1, UK) and API 20E (BIOMERIEUX, 20100), API 20E reagent kits (6 AMP, 20120) were likewise used.

2.3 Outcome Measure

After 24–48h of incubation, Listeria, Enterobacteriaceae and coliform colonies (betweem 30–300 colonies) on petric dish plates were counted and level of their contamination were expressed using United States Department of Agriculture (USDA, 2015) as colony-forming units per gram (cfu/g^− 1) using the multiplication of colonies counted per medium by total dilution used per sample and then divide all by the volume of cultured plates in ml and finally multiply by 10. then divide all by the volume of cultured plates in ml and finally multiply by 10. Occurrence of Incidence of Listeria, Enterobacteriaceae and coliform colonies (as Total Viable Count) was evaluated by dividing the number of specific or single positive ready-for-sale fruits and vegetables/Plate Agar/market/State to the total number of specific group of ready-for-sale fruits and vegetable/Agar Plate in all the media/market/States analysed in this study and then multiply by 100.

Prevalence of Listeria, Enterobacteriaceae and coliform colonies (as Total Viable Count) was by calculating the division of number of positive ready-for-sale fruits and vegetables/Plate Agar/market/State to the total number of ready-for-sale fruits and vegetable/Agar Plate in all the media/market/States analysed in this study and then multiply by 100.

3.1 Overview of the Analyzed Marketed Fresh Ready-For-Sale Fruits and Vegetables in Southwest, Nigeria

A total of 1108 isolates were gotten from 172 homogenized samples (out of 180 samples), from this study in all the five culturing agar. Moreover, the results from the API biochemical test denoted the presence of enteric pathogenic epiphytes. The pathogenic epiphytes are Raoultella ornithinolytica, Salmonella spp. Klebsiella pneumonia ssp pneumonia 1, Pasteurella pneumotropica, Serratia liquefacien, Serratia fonticola, Serratia marcescens, Stenotrophomonas maltphilio, Enterobacter cloacae, Pseudomonas luteola, Ochribactnim anthropi, Salmonella ficaria, Cedecae davisae and Cedesae lafagei. Escherichia hermannii, Pantoea spp., Escherichia coli, Leclercia decompoxylata, Klebsiella pneumonia spp ozaenia, Salmonella spp arizonae, Citrobacter braaki, Citrobacter freundii,, Salmonella enterica ssp arizonae, Entrobacter aerogenes were identified biochemically from the fresh produce purchased in open markets.

3.2 Effect of Differential Media on Prevalence of Pathogenic Epiphytes in Fruits and Vegetables in Southwest, Nigeria

3.2.1 Effect of all Differential Media on Prevalence of Pathogenic Epiphytes in Fruits and Vegetables in Southwest, Nigeria

Table 1a showed isolates recovered from all the media (both broth and agar) in all the samples of all markets in this study. Results from all the five media revealed Sabo and Ikorodu in Lagos State to have gotten the most number of isolates (58, 5.23%) while Shasha market in Ondo has the least number of isolates (17, 1.53%). From each culturing media, XLD Agar (188 isolates, 16.97%) favoured more growth when compared to BGA Agar (133 isolates, 12%). This trend of isolates is seen in PALCAM Agar (11.82% and 17.69%) in comparison to Oxford agar (12.09% and 11.10%) in those from Half-Fraser and Full-Fraser broths respectively (Table 1). Observation from VRBG agar plates recovered about 18.41% of isolates of which Alaba markets in Lagos State reveals the least percentage of the epiphytic isolate recovered with percentage of 2.80%. In Osun State (total isolate per market), Atamokunsa (4.96%) and Lagere (1.90%) markets have the highest and lowest concentration of isolates, with Owena in Ondo State having the highest percentage of recovered pathogens in Ondo State with percentage of 3.97%. Highest percentage of contamination with epiphytes with percentage values 3.07% was observed on the total isolate per market, in all the agar plates, containing Oja-Ale samples in Iwo while Oshodi (Lagos) and Shasha (Ondo) has least percentage of isolate by 0.63% in all the fresh produce in the three states. The highest contamination in Lagos State on VRBG was seen in Ile-Epo (1.35%) while the least value was found in Osun State with 1.08% in Oja-Titun, Ile-Ife, Osun State. Ondo State has Okitipupa market to have high percentage of contamination with epiphytes by 2.71% in all the fresh produce on VRBG agar.

Table 1

**a: Prevalence of Epiphytic Pathogens in Fresh Fruits and Vegetables per market in Southwest, Nigeria in various Differential Medium**
Samples/Market	VRBG	BGA	XLD	OXFh	OXFf	PALh	PALf	Total
1	9 (0.81)	6 (0.54)	7 (0.63)	8 (0.72)	5 (0.45)	2 (0.18)	9 (0.81)	46 (4.15)
2	9 (0.81)	6 (0.54)	11 (0.99)	5 (0.45)	8 (0.72)	10 (0.90)	9 (0.81)	58 (5.23)
3	7 (0.63)	6 (0.54)	6 (0.54)	6 (0.54)	5 (0.45)	10 (0.90)	7 (0.63)	47(4.24)
4	4 (0.36)	6 (0.54)	4 (0.36)	9 (0.81)	6 (0.54)	4 (0.36)	10(0.90)	43(3.88)
5	10 (0.90)	6 (0.54)	11 (0.99)	2 (0.18)	4 (0.36)	5 (0.45)	6 (0.54)	44 (3.97)
6	9 (0.81)	5 (0.45)	6 (0.54)	5 (0.45)	0 (0.00)	4 (0.36)	4 (0.36)	33(2.98)
7	7 (0.63)	6 (0.54)	10 (0.90)	2 (0.18)	3 (0.27)	10 (0.90)	4 (0.36)	42(3.79)
8	8 (0.72)	6 (0.54)	9 (0.81)	1 (0.09)	3 (0.27)	1 (0.09)	5 (0.45)	33(2.98)
9	7 (0.63)	6 (0.54)	6 (0.54)	4 (0.36)	5 (0.45)	3 (0.27)	3 (0.27)	34(3.07)
10	4 (0.36)	3 (0.27)	5 (0.45)	5 (0.45)	2 (0.18)	6 (0.54)	6 (0.54)	31(2.80)
11	11 (0.99)	6 (0.54)	9 (0.81)	6 (0.54)	1 (0.09)	6 (0.54)	6 (0.54)	45(4.06)
12	12 (1.08)	6 (0.54)	11 (0.99)	5 (0.45)	5 (0.45)	2 (0.18)	3 (0.27)	44(3.97)
13	10 (0.90)	6 (0.54)	10 (0.90)	4 (0.36)	7 (0.63)	6 (0.54)	7 (0.63)	50(4.51)
14	11 (0.99)	6 (0.54)	11 (0.99)	7 (0.63)	4 (0.36)	1 (0.09)	10 (0.90)	50(4.51)
15	10 (0.90)	6 (0.54)	10 (0.90)	4 (0.36)	6 (0.54)	5 (0.45)	8 (0.72)	49(4.42)
16	11 (0.99)	6 (0.54)	12 (1.08)	6 (0.54)	8 (0.72)	3 (0.27)	8 (0.72)	54(4.96)
17	12 (1.08)	6 (0.54)	8 (0.72)	0 (0.00)	4 (0.36)	4 (0.36)	6 (0.54)	40(3.61)
18	8 (0.72)	3 (0.27)	4 (0.36)	5 (0.45)	5 (0.45)	2 (0.18)	3 (0.27)	30(2.71)
19	2 (0.18)	2 (0.18)	3 (0.27)	6 (0.54)	3 (0.27)	5 (0.45)	0 (0.00)	21(1.90)
20	4 (0.36)	2 (0.18)	4 (0.36)	3 (0.27)	9 (0.81)	0 (0.00)	2 (0.18)	24(2.17)
21	5 (0.45)	3 (0.27)	3 (0.27)	7 (0.63)	6 (0.54)	1 (0.09)	1 (0.09)	26(2.34)
22	8 (0.72)	4 (0.36)	5 (0.45)	2 (0.18)	3 (0.27)	3 (0.27)	10 (0.90)	35(3.16)
23	4 (0.36)	4 (0.36)	5 (0.45)	6 (0.54)	6 (0.54)	5 (0.45)	14 (1.26)	44(3.97)
24	5 (0.45)	3 (0.27)	2 (0.18)	6 (0.54)	5 (0.45)	4 (0.36)	3 (0.27)	28(2.53)
25	4 (0.36)	3 (0.27)	3 (0.27)	4 (0.36)	1 (0.09)	4 (0.36)	3 (0.27)	22(1.99)
26	1 (0.09)	2 (0.18)	2 (0.18)	7 (0.63)	1 (0.09)	6 (0.54)	8 (0.72)	27(2.44)
27	3 (0.27)	2 (0.18)	3 (0.27)	3 (0.27)	2 (0.18)	2 (0.18)	12 (1.08)	27(2.44)
28	3 (0.27)	2 (0.18)	3 (0.27)	4 (0.36)	4 (0.36)	8 (0.72)	6 (0.54)	30(2.71)
29	2 (0.18)	2 (0.18)	1 (0.09)	1 (0.09)	1 (0.09)	1 (0.09)	9 (0.81)	17(1.53)
30	4 (0.36)	3 (0.27)	4 (0.36)	1 (0.09)	1 (0.09)	7 (0.63)	14 (1.26)	34(3.07)
Total	204(18.41)	133(12.00)	188(16.97)	134(12.09)	123(11.10)	130(11.82)	196(17.69)	1108 (100)

Lagos State:- Mile 12: 1; Ile-Epo: 2; Oyingbo: 3; Agege: 4; Musin: 5; Oshodi: 6; Lekki: 7; Balogun: 8; Sabo: 9; Alaba: 10; Osun State:- Igbona: 11; Orisunbare: 12; Ota Efun:13; Odori: 14; Oja Ale, Iwo: 15; Ilesha Atamokunsa: 16; Sabo Iwo: 17; Ifon Osun: 18; Lagere Ife: 19; Oja Titun Ife: 20; Ondo State:- Okitipupa Market: 21; Bolorunduro, Ondo: 22; Owena: 23; Akure Oja Oba: 24; Iloro: 25; Isinkan: 26; Alade: 27; Ikare Oja Oba: 28; Shasha: 29; Owo Oja-Oba:30

Xylose lysine Desoxycholate (XLD) Agar and Brilliant Green Agar (modified) (BGA); Violet Red Bile Glucose Agar (VRBG), Brilliant Green Bile Agar (modified) (BGA), Xylose lysine Desoxycholate (XLD), Violet Red Bile Glucose Agar (VRBG), Half Fraser Broth enriching OXFORD Agar (OXFh), Full- Fraser Broth enriching OXFORD Agar (OXFf), Half Fraser Broth enriching PALCAM Agar (PALh) and Full- Fraser Broth enriching PALCAM Agar (PALf)

3.2.2 Effect of VRBG, BGA and XLD Media on the Prevalence of Pathogenic Epiphytes in Fruits and Vegetables in Southwest, Nigeria

Results from Table 1b shows the isolates that have grown on three agar plates (VRBG, BGA and XLD agar). Focusing on cabbage, the lowest values (in percentage) in the three states were found in Okitipupa (0.63%) market in Ondo State. Increasing in trend of percentage of isolate of cabbage flowed from Lagos (1.71%), Osun (3.34%) and then Ondo States (3.70%). Moreso, marketted cabbage gotten from Mile 12 in Lagos State, Orisunbare in Osun State and Okitipupa in Ondo State with percentage of 0.45%, 0.54% and 0.63% respective are of highest percentage of isolate. Only five markets (Ile-Epo, Oshodi, Lekki, Balogun and Alaba), one market (Oja-Titun Ife) and two markets (Shasha and Oja-Oba, Owo) of all markets in Lagos, Osun and Ondo states respectively have cabbage that have no growth (This means that they are fitted for consumption).

For carrot samples, lowest values in the three states were found in Oja-Ale, Iwo (0.54%) markets found in Osun State,. Carrot samples from Lagos, Ondo and then Osun States had percentage of isolates recovered with values 2.98%, 3.61% and 3.70%. Highest number of isolates from carrot were found in Lagos, Osun and then Ondo States having values of 0.45%, 3.34% and 3.70% in individual markets Mile 12, Sabo (Iwo) and Okitipupa respectively. Only Shasha market has carrots that are do not have growth in the three agar and this deduce that they are acceptable for consumption as at the time of sample collections. Carrot respective range for the lowest and highest level of isolate recovered in the three states are: Lagos (0.09–0.36%), Osun (0.27–0.54%) and Ondo (0.00-0.45%).

More so, the range of cucumber microbial percentage of isolate recovery in the three states (from the three agar) was 0.09–0.45%. However, Lagos State (3.70%) has the highest percentage of isolates from cucumber per market, then Ondo (3.61%) which finally land to 3.43%. Only Ile-Epo market (0.18%) has contaminated garden egg in the whole of Lagos State. The range of percentage of isolate found in cucumber gotten from Osun State was between 0.09–0.54% while that of Ondo state was 0.00-0.45%. Ondo State (3.48%) garden egg was more contaminated compared to that of Osun State (2.80%). No market has contaminated tomato in Lagos State. The range isolate found in garden egg from Osun State was between 0.09–0.54% while that of Ondo state was 0.00-0.63%. Isolates from garden egg from Ondo State (3.16%) has more of these microbial contaminants compared to that of Osun State (2.89%). Actually, Mile 12 (0.09%), Ile-Epo (0.36%) and Oyingbo (0.09%) only have watermelon with microbial growth in Lagos State. Meanwhile, the range of percentage level of isolate from watermelon samples gotten in Osun State was from 0.27–0.54% while that of Ondo state was 0.00-0.45%.

Furthermore, tomatoes in Lagos were found to be safe for consumption with 0% of contamination. Lagos State also has the least microbial contaminants compaeed to other fresh produce with 0.18%, 0.54%, 1.71%, 2.98% and 3.70% in garden egg, watermelon, cabbage, carrot and cucumber respectively. In Ondo State, the decreasing tread of percentage of isolate were found in cabbage (3.70%), cucumber and carrot (3.61%), garden egg (3.48%) watermelon (3.16%), and then tomatoes (2.89%). This trend was not as the one found in Osun State. From percentage of fresh produce gotten from Osun State, values were gotten from garden egg and tomatoes (2.80%), cabbage (3.34%), water melon (3.61%) and then carrot (3.70%), watermelon (3.16%), Altogether, cucumber (10.74%) from this study has the highest percentage of growth rate of epiphytes, followed by carrot (10.29%), cabbage (8.75%), watermelon (7.04%), garden egg (6.41%) and then tomatoes (5.96%). Furthermore, from this study, Ondo State (20.40%) has the highest contaminated fruits and vegetables, following Osun (19.68%) and then Lagos State (9.21%), showing relative growth of epiphytes.

Table 1

**b: Prevalence of Epiphytic Pathogens in various of Fresh Fruits and Vegetables per market in Southwest, Nigeria on BGA, XLD and VRBG Agar**
Market		No of Isolates on VRBG, BGA and XLD
	Cabbage	Carrot	Cucumber	Garden Egg	Tomato	Watermelon	Total
1	5 (0.45)	1(0.09)	4 (0.36)	0(0.00)	0(0.00)	1(0.09)	11(0.99)
2	0(0.00)	4 (0.36)	5 (0.45)	2 (0.18)	0(0.00)	4 (0.36)	15(1.35)
3	4 (0.36)	2 (0.18)	5 (0.45)	0(0.00)	0(0.00)	1(0.09)	12(1.08)
4	4 (0.36)	4 (0.36)	4 (0.36)	0(0.00)	0(0.00)	0(0.00)	12(1.08)
5	3 (0.27)	4 (0.36)	3 (0.27)	0(0.00)	0(0.00)	0(0.00)	10(0.90)
6	0(0.00)	3 (0.27)	4 (0.36)	0(0.00)	0(0.00)	0(0.00)	7(0.63)
7	0(0.00)	3 (0.27)	5 (0.45)	0(0.00)	0(0.00)	0(0.00)	8(0.72)
8	0(0.00)	4 (0.36)	4 (0.36)	0(0.00)	0(0.00)	0(0.00)	8(0.72)
9	3 (0.27)	4 (0.36)	3 (0.27)	0(0.00)	0(0.00)	0(0.00)	10(0.90)
10	0(0.00)	4 (0.36)	5 (0.45)	0(0.00)	0(0.00)	0(0.00)	9(0.81)
Total	19(1.71)	33(2.98)	41(3.70)	2 (0.18)	0(0.00)	6 (0.54)	102(9.21)
11	5 (0.45)	4 (0.36)	3 (0.27)	4 (0.36)	2 (0.18)	4 (0.36)	22(1.99)
12	5 (0.45)	4 (0.36)	4 (0.36)	5 (0.45)	3 (0.27)	4 (0.36)	25(2.26)
13	3 (0.27)	3 (0.27)	3 (0.27)	4 (0.36)	3 (0.27)	4 (0.36)	20(1.81)
14	3 (0.27)	3 (0.27)	3 (0.27)	1(0.09)	1(0.09)	3 (0.27)	14(1.26)
15	5 (0.45)	6 (0.54)	5 (0.45)	6 (0.54)	6 (0.54)	6 (0.54)	34(3.07)
16	3 (0.27)	5 (0.45)	5 (0.45)	1(0.09)	3 (0.27)	4 (0.36)	21(1.90)
17	6 (0.54)	4 (0.36)	2(0.18)	4 (0.36)	4 (0.36)	4 (0.36)	24(2.17)
18	4 (0.36)	5 (0.45)	5 (0.45)	2 (0.18)	5 (0.45)	4 (0.36)	25(2.26)
19	3 (0.27)	4 (0.36)	3 (0.27)	3 (0.27)	2 (0.18)	4 (0.36)	19(1.71)
20	0(0.00)	3 (0.27)	3 (0.27)	1(0.09)	2 (0.18)	3 (0.27)	12(1.08)
Total	37(3.34)	41(3.70)	38(3.43)	31(2.80)	31(2.80)	40(3.61)	218(19.68)
21	7(0.63)	4 (0.36)	5 (0.45)	3 (0.27)	7(0.63)	4 (0.36)	30(2.71)
22	5 (0.45)	5 (0.45)	5 (0.45)	5 (0.45)	5 (0.45)	4 (0.36)	29(2.62)
23	3 (0.27)	5 (0.45)	5 (0.45)	5 (0.45)	3 (0.27)	5 (0.45)	26(2.35)
24	5 (0.45)	4 (0.36)	5 (0.45)	5 (0.45)	5 (0.45)	4 (0.36)	28(2.53)
25	5 (0.45)	5 (0.45)	3 (0.27)	4 (0.36)	4 (0.36)	4 (0.36)	25(2.26)
26	5 (0.45)	5 (0.45)	4 (0.36)	5 (0.45)	5 (0.45)	4 (0.36)	282.53)
27	5 (0.45)	4 (0.36)	3 (0.27)	4 (0.36)	5 (0.45)	5 (0.45)	26(2.35)
28	5 (0.45)	3 (0.27)	5 (0.45)	0(0.00)	0(0.00)	2 (0.18)	15(1.35)
29	0(0.00)	0(0.00)	1(0.09)	5 (0.45)	1(0.09)	0(0.00)	7(0.63)
30	0(0.00)	5 (0.45)	4 (0.36)	2 (0.18)	0(0.00)	0(0.00)	214(19.31)
Total	41(3.70)	40(3.61)	40(3.61)	38(3.48)	35(3.16)	32(2.89)	11(0.99)
Overall Total	97(8.75)	114(10.29)	119(10.74)	71(6.41)	66(5.96)	78(7.04)	546(49.28)

Lagos State:- Mile 12: 1; Ile-Epo: 2; Oyingbo: 3; Agege: 4; Musin: 5; Oshodi: 6; Lekki: 7; Balogun: 8; Sabo: 9; Alaba: 10; Osun State:- Igbona: 11; Orisunbare: 12; Ota Efun:13; Odori: 14; Oja Ale, Iwo: 15; Ilesha Atamokunsa: 16; Sabo Iwo: 17; Ifon Osun: 18; Lagere Ife: 19; Oja Titun Ife: 20; Ondo State:- Okitipupa Market: 21; Bolorunduro, Ondo: 22; Owena: 23; Akure Oja Oba: 24; Iloro: 25; Isinkan: 26; Alade: 27; Ikare Oja Oba: 28; Shasha: 29; Owo Oja-Oba:30

Xylose lysine Desoxycholate (XLD) Agar and Brilliant Green Agar (modified) (BGA); Violet Red Bile Glucose Agar (VRBG), Brilliant Green Bile Agar (modified) (BGA), Xylose lysine Desoxycholate (XLD), Violet Red Bile Glucose Agar (VRBG)

3.3.3 Effect of OXFORD Agar, PALCAM agar, Half-Fraser Broth and Feull-Fraser Broth on Prevalence of Pathogenic Epiphytes in Fruits and Vegetables in Southwest, Nigeria

Table 1c showed the performance effect of OXFORD and PALCAM agar in the isolation of epiphytes from marketed ready–for-sale fruits and vegetables in Southwest Nigeria. The total percentage of isolates gotten from BGA, XLD and VRBG Agar as well as on both OXFORD and PALCAM Agar in this study are 546 isolates (49.28%) and 562 (50.72%), as shown in Table 1b and 1c. In Table 1c, Agege market in Lagos has the most number of isolates (35, 3.16%) from all the media while Lagere, Ife market in Osun has the least number (9, 0.81%). The whole of the three states from this study, has decreasing percentage of isolate recovered in fresh produce by the following: cabbage (10.56%), cucumber (9.66%), tomatoes (8.94%). garden egg (8.03%) carrot (6.86%), and watermelon (6.68). Furthermore, this study showed Lagos State percentage of isolates recovered to be 3.16%, 2.89% and 2.53% in Agege, Ile-Epo and Oyingbo respectively, as highest amoung other states. Lagere Ife in Osun State has the least isolates recovered in all the fresh produce with 0.81%, In Ondo and Osun States, the three markets with highest percentage of isolates recovered were Isikan (2.35%), Iloro (2.17%) and Okitipupa (1.99%) with Owena (2.44%), Ikare Oja-Oba (2.44%) and Isinkan (1.99%) respectively.

Prevalence of pathogenic epiphytes from three states decrease with cabbage from Ondo (4.33%), Lagos (3.52%) and Osun (2.71); Osun (2.80%), Lagos (2.26%) and Ondo (1.81%) in carrot; Ondo (3.52%), Osun (3.25%) and Lagos (2.89%) for cucumber; Lagos (4.15% and 3.61%), Osun (2.17% and 2.89%) and Ondo (1.71% and 2.44) for garden egg and tomato; Lagos (2.98% and 19.40%), Ondo (1.99% and 15.79%) and Osun (1.71% and 15.52) for watermelon and all fresh produce respectively.

Fresh produce showed increasing prevalence of epiphytes from carrot (2.26%), cucumber (2.89%), watermelon (2.98%), cabbage (3.52%), tomatoes (3.61%) and garden egg (4.15%) in Lagos; In Osun State, results showed water melon (1.71%), garden egg (2.17%), cabbage (2.71%), carrot (2.80%), tomatoes (2.89%) and cucumber (3.25%); and for Ondo State, garden egg (1.71%), carrot (1.81%), watermelon (1.99%), tomatoes (2.44%) cucumber (3.52%) and cabbage (4.33%). Moreover, market with the highest and the least percentage of contamination in cabbage samples from Lagos, Osun and Ondo are Ile-Epo (0.72%) and Oshodi (0.54%); Owena (0.54%) and Oja-Oba, Owo (0.00%); with Oja-Oba, Akure (0.72%), Isinkan (0.72%) and Owena (0.09%) respectively.

Carrot from Lagos State, the lowest isolate recovered were found in markets Oyingbo, Musin, Oshodi and Alaba (0.00%) while Agege and Oshodi (0.54%) reflect the highest value. Cucumber, garden egg, tomato and watermelon in this state had high number of isolates in markets Ile-Epo and Oyingbo (0.54%), Mile 12 and Agege (0.72), Mile 12, Oyingbo and Agege (0.54%) and Ile-Epo (0.72%) respectively. Meanwhile the least number of isolate percentage was seen in markets Oshodi and Balogun (0.00%), Oshodi and Sabo, Ikorodu (0.18%), 9(0.09%), as well as Musin and Alaba (0.09%). Markets like Atamokunsa and Ifon-Osun (0.54%), Oja-Titun (0.63%), Oja-Oba Ikare (0.72%), Oshodi (0.54%) and Agege (0.36%) respectively have the highest recovered isolate for carrot, cucumber, garden egg, tomato and watermelon in Osun State. Likewise, the least percentage isolates recovered in Osun State were observed in markets Oja-Oba Owo (0.00%), Okitipupa and Iloro (0.09%), Iloro, Isinkan and Oja-Oba Owo (0.00%), Alade (0.00%) and Bolorunduro and Oja-Oba Ikare (0.00%).

Furthermore, in Ondo State, carrot, cucumber, garden egg, tomato and watermelon with high isolate percentage were from the markets Isinkan (0.36%), Bolorunduro and Isinkan (0.63%), Owena, Oja-Oba Akure, Isinkan and Oja-Oba Ikare (0.27%), Iloro (0.45%) and Owena (0.45%). Finally, in Ondo State, the least percentage of isolate recovered were from carrot, cucumber, garden egg, tomato and watermelon which were observed in the following markets respectively: Bolorunduro, Owena, Oja-Oba Akure, Oja-0ba Ikare and Oja-Oba Owo (0.09%), Oja-Oba Owo (0.09%), Okitipupa (0.00%), Oja-0ba Ikare and Shasha (0.00%), with Bolorunduro and Oja-0ba Ikare (0.09%).

Table 1

**c: Prevalence of Epiphytic Pathogens in various of Fresh Fruits and Vegetables per market in Southwest, Nigeria on OXFORD and PALCAM Agar**
Market		No of Isolates on both OXFORD and PALCAM Agar
	Cabbage	Carrot	Cucumber	Garden Egg	Tomato	Watermelon	Total
1	2 (0.18)	2 (0.18)	4 (0.36)	8(0.72)	6 (0.54)	3 (0.27)	25(2.26)
2	8(0.72)	1(0.09)	6 (0.54)	4 (0.36)	5 (0.45)	8(0.72)	32(2.89)
3	6 (0.54)	0(0.00)	6 (0.54)	5 (0.45)	6 (0.54)	5 (0.45)	28(2.53)
4	5 (0.45)	6 (0.54)	4 (0.36)	8(0.72)	6 (0.54)	6 (0.54)	35(3.16)
5	3 (0.27)	0(0.00)	1(0.09)	4 (0.36)	7(0.63)	1(0.09)	16(1.44)
6	1(0.09)	6 (0.54)	0(0.00)	2 (0.18)	2 (0.18)	2 (0.18)	13(1.17)
7	2 (0.18)	5 (0.45)	4 (0.36)	3 (0.27)	3 (0.27)	2 (0.18)	19(1.71)
8	3 (0.27)	0(0.00)	0(0.00)	3 (0.27)	2 (0.18)	2 (0.18)	10(0.90)
9	6 (0.54)	5 (0.45)	2 (0.18)	2 (0.18)	1(0.09)	3 (0.27)	19(1.71)
10	3 (0.27)	0(0.00)	5 (0.45)	7(0.63)	2 (0.18)	1(0.09)	18(1.62)
Total	39(3.52)	25(2.26)	32(2.89)	46(4.15)	40(3.61)	33(2.98)	215(19.40)
11	2 (0.18)	3 (0.27)	1(0.09)	2 (0.18)	5 (0.45)	2 (0.18)	15(1.35)
12	3 (0.27)	4 (0.36)	3 (0.27)	3 (0.27)	4 (0.36)	2 (0.18)	19(1.71)
13	6 (0.54)	3 (0.27)	5 (0.45)	4 (0.36)	6 (0.54)	3 (0.27)	27(2.44)
14	4 (0.36)	1(0.09)	4 (0.36)	3 (0.27)	1(0.09)	1(0.09)	14(1.26)
15	3 (0.27)	4 (0.36)	1(0.09)	0(0.00)	1(0.09)	1(0.09)	10(0.90)
16	5 (0.45)	6 (0.54)	5 (0.45)	0(0.00)	5 (0.45)	1(0.09)	22(1.99)
17	2 (0.18)	3 (0.27)	3 (0.27)	3 (0.27)	0(0.00)	4 (0.36)	15(1.35)
18	4 (0.36)	6 (0.54)	5 (0.45)	8(0.72)	2 (0.18)	2 (0.18)	27(2.44)
19	1(0.09)	1(0.09)	2 (0.18)	1(0.09)	3 (0.27)	1(0.09)	9(0.81)
20	0(0.00)	0(0.00)	7(0.63)	0(0.00)	5 (0.45)	2 (0.18)	14(1.26)
Total	30(2.71)	31(2.80)	36(3.25)	24(2.17)	32(2.89)	19(1.71)	172(15.52)
21	6 (0.54)	3 (0.27)	3 (0.27)	0(0.00)	4 (0.36)	2 (0.18)	18(1.99)
22	2 (0.18)	1(0.09)	7(0.63)	1(0.09)	3 (0.27)	1(0.09)	15(1.35)
23	1(0.09)	1(0.09)	3 (0.27)	3 (0.27)	4 (0.36)	5 (0.45)	16(1.44)
24	8(0.72)	1(0.09)	3 (0.27)	3 (0.27)	4 (0.36)	3 (0.27)	22(1.99)
25	7(0.63)	3 (0.27)	5 (0.45)	2 (0.18)	5 (0.45)	2 (0.18)	24(2.17)
26	8(0.72)	4 (0.36)	7(0.63)	3 (0.27)	1(0.09)	3 (0.27)	26(2.35)
27	3 (0.27)	3 (0.27)	4 (0.36)	1(0.09)	4 (0.36)	2 (0.18)	17(1.53)
28	6 (0.54)	1(0.09)	3 (0.27)	3 (0.27)	0(0.00)	1(0.09)	14(1.26)
29	4 (0.36)	2 (0.18)	3 (0.27)	1(0.09)	0(0.00)	2 (0.18)	12(1.08)
30	2 (0.18)	1(0.09)	1(0.09)	2 (0.18)	2 (0.18)	2 (0.18)	10(0.90)
Total	48(4.33)	20(1.81)	39(3.52)	19(1.71)	27(2.44)	22(1.99)	175(15.79)
Overall Total	117(10.56)	76(6.86)	107(9.66)	89(8.03)	99(8.94)	74(6.68)	562(50.72)

Lagos State:- Mile 12: 1; Ile-Epo: 2; Oyingbo: 3; Agege: 4; Musin: 5; Oshodi: 6; Lekki: 7; Balogun: 8; Sabo: 9; Alaba: 10; Osun State:- Igbona: 11; Orisunbare: 12; Ota Efun:13; Odori: 14; Oja Ale, Iwo: 15; Ilesha Atamokunsa: 16; Sabo Iwo: 17; Ifon Osun: 18; Lagere Ife: 19; Oja Titun Ife: 20; Ondo State:- Okitipupa Market: 21; Bolorunduro, Ondo: 22; Owena: 23; Akure Oja Oba: 24; Iloro: 25; Isinkan: 26; Alade: 27; Ikare Oja Oba: 28; Shasha: 29; Owo Oja-Oba:30

3.4 Fresh Produce Pathogenic Epiphytes Risk Levels

Coliforms with other Enterobacteriaceae were recovered on Violet Red Bile Glucose Agar (VRBG, TM MEDIA, India) from fresh produce in this study. Figure 1 shows the microbial levels of fresh produce counted from all the five agar plates. Total Viable Count (TVC) for cabbage samples gotten from Lagos, Osun and Ondo states ranges from 0.00*10⁰-2.44 x 10⁴ cfu/g in all the markets with distribution of 0.00 x 10⁰-1.66 x 10⁴, 0.00 x 10⁰-1.98 x 10⁴ and 0.00 x 10⁰-2.44 x 10⁴ cfu/g respectively. Cabbage samples gotten from Owena market in Ondo State has the highest TVC (2.44*10⁴ cfu/g). Low level of TVC was observed in cabbage samples from both Igbona (1.98 x 10⁴ cfu/g) and Ifon-Osun (1.98 x 10⁴ cfu/g) in Osun State as well as Mile 12 market (1.66 x 10⁴ cfu/g) in Lagos State. Growth of epiphytic bacteria were not detected in cabbage obtained from Alaba, Lagos State; Lagere and Oja-Titun in Osun States as well as in some of the Ondo markets like Iloro, Isinkan, Alade, Oja-oba (in both Ikare and Akure) and Oja-Oba (Owo). Only cabbage without viable growth of pathogens are fitted for consumption as shown in Fig. 1a.

Total Coliform Count were recovered on both Brilliant Green Bile Agar (modified) (BGA, FLUMEDIA, HF016) and XLD Agar (TM492). Viable growth range of pathogens were observed in Fig. 1b, on both XLD agar (0.00 x 10⁰-1.54 x 10², 0.00 x 10⁰-2.84 x 10² and 0.00 x 10⁰-9.00 x 10¹ cfu/g) and BGA (0.00 x 10⁰-1.20 x 10², 0.00 x 10⁰-1.52 x 10² and 0.00 x 10⁰-2.46 x 10¹ cfu/g) in Lagos, Osun and Ondo States. It was noticed that XLD Agar favour more growth in most cabbage samples when compared to BGA. XLD agar have highest sensitivity, differential ability and effectiveness but low selectivity compared to BGA. This shows evidence in cabbage samples from Bolorunduro market (1.54 x 10² cfu/g), Okitipupa (7.80 x 10¹ cfu/g) and Oja-Oba (4.60 x 10¹ cfu/g) in Owo which has viable epiphytic pathogens on XLD agar that are not isolated on BGA. Highest growth was found on XLD agar from cabbage samples from Osun State markets: Oja-Ale (Iwo, 2.84 x 10² cfu/g) and Ifon-Osun (2.68 x 10² cfu/g) while on BGA, highest growth was seen in Okitipupa market (2.46x 10² cfu/g) in Akure, shown in Fig. 1b. Cabbage samples that were regarded to be safe for consumption are gotten from Alaba (Lagos), Lagere and Oja-Titun (Ife) in Osun State, with Isikan, Alade, Oja-Oba (Ikare) and Shasha markets in Ondo State because they have no viable growth of epiphytes.

Cabbage samples plated on PALCAM Agar (PAL, Oxoid, CM0877), Listeria Selective Agar Base (Oxford Formulation, OXF, CM0856) were enriched in both Half Fraser Broth (h) and Fraser Broth (f, OXOID, CM0895 ISO, United Kingdom) with other supplements mentioned earlier. Gram positive bacteria such as Listeria spp with others such as Staphylococcus aureus and Enterococcus faecalis can selectively grow on PALCAM agar. PALCAM have the highest sensitivity, differential ability and effectiveness but low selectivity compared to oxford agar. Half Fraser Broth also enhance these abilities in the agar. The microbial levels (Fig. 1c) in OXFh, OXFf, PALh and PALf ranged from 0.00 x 10⁰-3.60 x 10¹, 0.00 x 10⁰-4.80 x 10¹, 0.00 x 10⁰-8.80 x 10¹ and 0.00 x 10⁰-6.80 x 10¹ cfu/g respectively.

Obviously, highest growth were observed mostly on PALCAM Agar compared to that of OXFORD Agar as observed in Fig. 1c. From PALCAM Agar enriched from half-fraser broth has higher viable count compared to that from full fraser broth. Higher growth observed are found in the following markets: Owena (8.80 x 10¹ cfu/g), Okitipupa (6.40 x 10¹ cfu/g) and Oja-Oba (Owo, 7.20 x 10¹ cfu/g) in Ondo States; Ota-Efun (7.00 x 10¹ cfu/g); Odori (6.80 x 10¹ cfu/g), Lagere (Ilesha, 5.40 x 10¹ cfu/g) and Sabo (Iwo, 4.60 x 10¹ cfu/g) in Osun States; with Balogun markets (4.60 x 10¹ cfu/g) in Lagos States. Also, from isolates on PALCAM Agar plate enriched from Full-fraser Broth, it was observed that Odori (5.60 x 10¹ cfu/g), Sabo (Iwo, 6.80 x 10¹ cfu/g), Okitipupa and Idanre (6.20 x 10¹ cfu/g) markets has cabbage with higher microbial growth. More so, microbes enumerated from OXFh and OXFh have their highest growth in cabbage samples from Isikan in Akure (4.8x 10¹ cfu/g) and Ifon-Osun (5.00x 10¹ cfu/g) markets respectively.

Carrots purchased from Atamokunsa (Ilesha), Ota-Efun, Isinkan (Akure) are found to be free from pathogenic epiphytes while those from Odori (6.53 x 10⁴ cfu/g), Oja-Ale (Iwo, 8.16 x 10⁴ cfu/g), Sabo (Iwo) 3.25 x 10⁴ cfu/g), Oja-Titun (6.29 x 10⁴ cfu/g) and Lagere (Ilesha, 5.23 x 10⁴ cfu/g) possess substantial amount of epiphytes (Fig. 1d). All carrot samples from Fig. 1d in all markets have relative microbial growth except those from Ota-Efun and Igbona markets. Meanwhile, in Fig. 1e, out of all TVC from this study, those from Oja-Ale, Iwo (4.42 x 10² and 6.70 x 10² cfu/g) and Oja-Titun (9.12 x 10² and 8.16 x 10² cfu/g) at Ilesha have tremendous growth in both BGA and XLD Agar respectively. As seen from Fig. 1f, from carrot samples, Agbalata-Badagry, Oyingbo and Ile-Epo reveals no growth on Palcam agar but with higher growth in markets at Lagos, precisely at Balogun (4.80 x 10¹ cfu/g), Lekki and Fagba (6.20 x 10¹ cfu/g) as well as Mile 12 (8.80 x 10¹ cfu/g). Corresponding result was found in Osun State at Odori (4.80 x 10¹ cfu/g), Lagere (9.20 x 10¹ cfu/g) and Ifon-Osun (5.40 x 10¹ cfu/g) markets. In Ondo State, growth of epiphytes from cucumber are favoured on both agar with range 2.00-5.80 x 10¹ cfu/g.

Epiphytes from cucumber range between 0.00 x 10⁰ and 4.29 x 10⁴ cfu/g. Those from Mile 12, Ile-Epo, Ota-Efun, and Oja-Oba (Owo) reveals no growth. Lagere at Ilesha (Fig. 1g) has highest number of count with values 4.29 x 10⁴ cfu/g. All the cucumber samples analysed showed viable bacteria growth (Fig. 1h). Samples from Lagos state showed a relatively low level of the microbial hazard compared to other states. Higher growth are thereby observed in Ondo samples. However, there is substantial growth range of count per state which consist of Lagos (3.20 x 10²-1.34 x 1.0² cfu/g), Osun (2.40 x 10¹-4.40 x 10² cfu/g) and Ondo (6.40 x 10¹- 4.86 x 10² cfu/g) in both agar. All the cucumber samples analysed showed viable bacteria growth (Fig. 1i) except for Lekki and Agege samples. Samples range shows from 0.00 x 10⁰-4.60 x 10¹ cfu/g, Osun (0.00 x 10⁰-8.0 x 10¹ cfu/g) and Ondo (0.00 x 10⁰-8.0 x 10¹ cfu/g) in all the medium.

In addition, Garden egg from Lagos State markets is loaded with bacterial growth compared to others states (Fig. 1j) Garden egg gotten from Balogun, Lekki, Orisumbare and Ile-Epo markets revealed no bacterial growth. Ota-Efun market shows a remarkable growth amidst other market in Osun State. There is no growth in garden egg samples purchased from Ondo state except those ones from Bolorunduro market with microbial load of 4.42 x10³ cfu/g. The range of bacterial growth in the three states are 0.00 x 10⁰-2.52 x 10⁴ cfu/g.

Microbial levels (Fig. 1k) in BGA and XLD agar ranged from 0.00 x 10⁰-2.34 x 10² and 0.00 x 10⁰-1.50 x 10² cfu/g respectively. Out of all the ten market in Ondo State, Isikan market only showed a positive sample of 1.50 x 10² cfu/g. All market samples in Lagos State shows positive samples on BGA but there was no growth on XLD Agar for Lekki, Fagba and Ile-Epo markets for all the samples. Actually, in Osun State, only Igbona market does not have growth on both agar but Orisunbare market does not have at all. Garden egg in Lagos State showed positive samples in all the markets in Lagos State (Fig. 1l). Odori, Ifon-Osun, Okitipupa, Shasha and Owena markets got no bacterial growth. Other markets bacterial count range from 2.00 x 10¹-2.60 x 10¹, 1.00 x 10¹-6.20 x 10¹, 1.4 x 10¹-6.60 x 10¹ and 1.00 x 10¹-6.20 x 10¹ cfu/g for OXFh, OXFf, PALf and PALf respectively.

On VRBG, out of 30 markets, majority of the the tomato samples gotten were free from bacterial growth. The most of Osun and Lagos State showed levels from 4.16 x10³-8.4..42 x 10⁴ cfu/g. Odori market has the highest values of microbial load (Fig. 1m). The XLD Agar and BGA agar plates from tomato have bacterial growth on all the markets of both in Lagos and Osun States except in Orisumbare, Ota-Efon and Igbona. Ondo State does not have growth as that found on VRBG Agar except for Shasha market with values 1.00 x 10¹ -2.22 x 10² cfu/g. Microbial level range of tomatoes from Osun and Lagos States on BGA and XLD Agar are 0.00 x10⁰-2.68x10² and 0.00 x 10⁴-6.48 x 10² cfu/g (Fig. 1n). As seen from Fig. 1o, tomatoes from Orisunbare, Ota-Efun, Idanre and Oja-Oba markets were found to be void of bacterial load on these media. The range for the growth on the media is from 0.00 x 10⁰ and 6.60 x 10¹ cfu/g.

The VRBG Agar plate from watermelon have bacterial growth on all the markets of both in Lagos and Osun States except in Sabo (Iwo), Ota-Efun and Igbona markets. Here also, the Ondo State market watermelon samples does not have growth except for Oja-Oba Akure market with values 1.74 x 10² cfu/g. Microbial level range of watermelon from Osun and Lagos States on this agar are 7.28 x10³-4.06 x 10⁴ cfu/gand 0.00 x 10⁰-5.33 x 10⁴ cfu/g respectively (Fig. 1p). As seen from Fig. 1o, Orisunbare, Ota-Efun, Idanre and Oja-Oba markets were found to be void of bacterial load on these media, for tomaotoes. In Fig. 1r, all watermelon samples in every markets have colony count or bacterial growth in one or two of the media. The range for the growth on the media for watermelon samples is from 0.00 x 10⁰ and 6.60 x 10¹ cfu/g and 0.00 x 10⁰ and 8.80 x 10¹ cfu/g (from Fig. 1o and 1r) respectively. This is aligned with Angela et al. (2010). XLD Agar and BGA watermelon plates have microbial growth on all the markets of both in Lagos and Osun States except in Orisumbare, Ota-Efon and Igbona. Ondo State does not have growth as that found on VRBG Agar except for Iloro and Oja-Oba markets with values 2.54 x 10²-4.68 x 10². Microbial level range from Osun and Lagos States on BGA and XLD Agar are 0.00 x10⁰-8.16 x 10² cfu/g and 0.00 x 10⁴-4.62 x 10² cfu/g respectively as shown in Fig. 1q. Sabo (Iwo) and Oja-Titun Ilesha markets have the highest values of microbial load.

3.5 Pathogenic Epiphytes Occurrence/Incidence in Fruits and Vegetables

On VRBG Agar, it was shown that all samples from all market in different states had viable count but it vary with different samples. In Lagos State, Only cabbage from Ile-Epo has no growth on VRBG Agar but it has growth of epiphytes on other differential and selective agar. For watermelon (100%), carrot (100%), cucumber (80%) and tomato (50%), were observed to have unsatisfactory samples in terms of microbial safety. Three marketed garden egg samples were found contaminated from both Ondo (Atamokunsa, Lagere and Ota-Efun) and Lagos (Balogun, Lekki and Agege) States. Osun state samples has the highest number of fresh produce contamination.

Cabbage purchased from only three markets (Lagere, Ota-Efun and Iloro) are fit for consumption because of no growth of epiphytes observed. Just Ota-Efun market has watermelon and cucumber which are safe for consumption due to no growth of epiphytes detected. Fifty and twenty percents of the market have substantial microbial growth on tomato and carrot samples respectively. Ondo State had the least samples contaminated with respect to markets when compared with other states. Carrots in all the markets were found contaminated except for Isikan market alone. This trend was also found in cucumber in which those gotten from Owena and Oja-Oba (Owo) have no viable count on VRBG plate. Only watermelon and garden egg gotten from Oja-Oba in Akure has viable growth (Fig. 2a). There was no tomato contamination in all the markets. Four markets were found to have contaminated cabbage samples (Iloro, Isinkan, Bolorunduro, and Oja-Oba in Owo).

For all the thirty markets, six different samples (watermelon, tomato, cucumber, carrot, garden egg and cabbage) are plated on BGA, Lekki, and Odori markets have 5 samples with growth of epiphytes, Ile-Epo and Isinkan markets have four, three from Orisunbare, Iloro, Oja-Oba (Akure), Bolorunduro, Okitipupa, Oja-Oba (Owo) and Shasha and two from Ota-Efun, Igbona, Owena, Idanre, Oja-Oba (Ikare). Fifty percent of all the markets have all their fresh produce have epiphyte growth. Such markets are Alaba, Sabo (in Ikorodu and Iwo), Agbalata-Badagry, Balogun, Oyingbo, Fagba, Agege, Odori, Oja-Ale, Atamokunsa, Oja-Titun, Lagere and Ifon-Osun (Fig. 2b).

Out of ten markets per state, all markets (Alaba, Sabo in Ikorodu, Agbalata-Badagry, Balogun, Oyingbo, Fagba, Agege, Mile 12 and Ile-Epo) in Lagos States have contaminated watermelon, 7 markets (Odori, Oja-Ale, Sabo (Iwo), Atamokunsa, Oja-Titun, Lagere and Ifon-Osun) from Osun and 2 States from Ondo which include Iloro and Oja-Oba (Akure) markets. All the 30 markets have cucumber to be contaminated. This is likewise found in Carrot except two markets (Ota-Efun from Osun States and Iloro from Ondo State) and in Garden egg except for Orisumbare and Igbona from osun Isinkan from Ondo State.

Observing tomato samples on BGA, 90% of the ten markets in Lagos, 60% in Osun and 10% in Ondo States have contaminated tomato samples. Meanwhile, Lekki and Ile-Epo (Lagos State), Ota-Efun and Igbona (Osun State) and Oja-Oba in Akure, Owena, Idanre, Oja-Oba in Ikare and Shasha in Owo have their cabbage free from microbial load on BGA. This was in consonance with the finding of Erinle and Ajayi who deduced that farmers’ open-market are versatile route pathogenic epiphytes infect fresh produce no matter the good agricultural practice employed.

On XLD Agar (Fig. 2c), Agbalata-Badagry,Oyingbo, Fagba,Agege, Sabo (in Ikorodu and Iwo), Atamokunsa, Oja-Titun, Lagere and Ifon-Osun also have all their fresh produce with epiphytes growth. All markets (Alaba, Sabo in Ikorodu, Agbalata-Badagry, Balogun, Oyingbo, Fagba, Agege, Mile 12 and Ile-Epo) in Lagos States; six states (Odori, Sabo (Iwo), Atamokunsa, Oja-Titun, Lagere and Ifon-Osun) from Osun and one States from Ondo which is Oja-Oba (Akure) markets. Only Oja-Oba in Owo have no microbial load of epiphytes with all cucumber samples in this study. Ota-Efun and Orisumbare from Osun States together with Iloro and Owena from Ondo State do not have bacterial load count with carrot samples. Lekki, Fagba, Ile-Epo, Orisumbare and all samples from all markets in Ondo states do not have bacterial count with garden egg. This trend is seen in tomato samples. Alaba, Mile 12, Orisumbare, Ota-Efun Igbona and and all samples from all markets in Ondo states do not have bacterial count with tomato samples. Meanwhile, Alaba and Ile-Epo (Lagos State), Ota-Efun and Orisumbare (Osun State) have their cabbage free from microbial load on BGA but Iloro and Isinkan in Owo only have contaminated cabbage with epiphytes in Ondo State.

The results from Fig. 2d revealed that all fresh produce marketed in Lagos, Osun and Ondo State of the Southwest, Nigeria have incidence of pathogenic bacteria sub-cultured from half-fraser broth on OXFORD Agar. Though, watermelon from Ifon-Osun have only 2 cfu/g while watermelon from Lagere, Ota-Efun and Igbona in other Osun States have no microbial count on OXFh. Cucumber (40%), Tomato and Garden egg (50%) with Cabbage and Carrot (80%)are found polluted with microbes. In Ondo State, Watermelon (80%), Cucumber (60%), Tomato (50%), Garden egg (60%), Cabbage (30%) and Carrot (40%) are safe for consumption due to no microbial growth. It was observed in Lagos States that microbial contaminant (epiphytes) was quite present especially in Watermelon, Cucumber, Tomato, Garden egg, Cabbage and Carrot by 70, 40, 70, 50, 50 and 50% respectively. Out of the 30 markets in Fig. 2e, markets that have watermelon, cabbage, cucumber, garden egg, tomato and carrot unsafe for consumption are Odori, Okitipupa, Oja-Titun Ife, Atamokunsa, Atamokunsa and Alaba respectively.

The results from Fig. 2f revealed that all fresh produce marketed in Lagos, Osun and Ondo State of the Southwest, Nigeria have incidence of pathogenic bacteria sub-cultured from half-fraser broth on PALCAM Agar except those from Igbona market. Though, watermelon has 30%, 20% and 10% contamination rate in all the samples from Lagos, Osun and Ondo States. For 66.66%, 20%, 30%, 50%, 43.33% and 56.67% of Cucumber, Watermelon, Cabbage, Tomato, Carrot, Garden egg and cabbage samples respectively are not acceptable for consumption in order to ensure safety precaution. Moreso, in Fig. 2g, from all the 30 markets of the Southwest, Nigeria, Bolorunduro (Ondo) and Ifon-Osun markets have watermelon and cabbage to unsafe for consumption respectively, Shasha and Isinkan markets have contaminated cucumber and garden egg samples with epiphytes, Alade and Bolorunduro markets have their tomato and carrot samples polluted respectively.

Santos et al. (2020) analysed that Enteriobacteriaceae covers like 82.5% of all the bacteria community in fresh fruits and vegetables. Considering XLD Agar in this study, it was detected that this medium favoured more growth, when compared to BGA Agar. This could be as a result of autoclaving of BGA Agar during sterilization of the medium, while boiling is just used on XLD agar. It has been reported that media prepared particularly through autoclaving and over-heating, may adversely reduce the performance and sensitivity of the media. This could be due to the enhancement of auto-oxidation of phosphate buffers and sugars, affecting growth rate of bacteria (Baylis et al., 2000). Many preferred the used of XLD to BGA due to its clearness, high sensitivity and performance in supporting the growth of enteric bacteria but its selectivity is quite low compared to BGA Agar.

ON VRBG Agar, the highest levels of recovered epiphytic bacteria in fresh samples were found in Atamokunsa and Owena markets. These wet-opened markets have their surroundings dirty and the handlers were not with clean hands or with protecting gloves while the produce were being handled. Contamination might have occurred through cross contamination while the fruits and vegetables were displayed for sales. Some of the markets with lower microbial load may be due to short holding time of fresh produce from the time they were brought from farm and time they were sold after opened-display for sales in markets.

Listeria from this study conformed to Fraser and Sperber (1988) who proved that Fraser Broth could detect Listeria accurately in food and clinical samples. He further recovered Listeria spp in 17% of 1,025 food samples. Meanwhile, PALCAM Agar’s performance and sensitivity rate is on the increase compared to Oxford agar. Its selectivity was not as high as to that of oxford agar and this helped to increase the number of bacteria isolate on it. More Listeria were recovered from OXFORD Agar compared to PALCAM Agar. This is also supported by Madajczak et al. (2012). On PALCAM and OXFORD Agar, all most all markets showed relative growth including tomato samples from Lagos State and other samples denoting no growth on VRBG, BGA and XLD Agar. So, it could be that another epiphytic bacteria were found on it which was revealed on PALCAM and OXFORD Agar.

Southwest open markets’ fringes are full of filthy heaps of decaying and rotten fruits and vegetables which could be a source of cross-contamination to freshly harvested fruits and vegetables. This has to be curbed in order to avoid pandemic outbreak. Another observation from sample collection markets is that many buyers which are the retailers bombarded the offloading of fresh samples (on the marshy area or dirty warehouse), trying to get fresh produce unhygienically. All these add to the higher load count of bacteria found in this study. Hence, poor sanitariness practices, low environmental and personal hygiene, improper handling of fruits, improper storage with improper trading techniques are the cause of microbial hazards in open market of fruits and vegetables.

Many research work on fruits and vegetables are mostly on the street vended sliced produce due to many more source of contaminants attached to such food handling (slicing, vending in hot weather and rapping in polyethylene bag) (Orji et al. 2016; Chinakwe et al., 2022). However, limited work was done on whole fruits and vegetables. The higher demand for the whole fresh produce cause many trunk to come into Southwest Nigerian market loaded with fresh produce, from a long distant as Northern Nigeria, without maintaining cold storage environment nor ensuring good transporting technique. In Lagos, many of the trucks offload in Mile 12 and other markets on marshy market soil without any concern about food safety. This deduce why Sabo Ikorodu, Lagos has the most number of isolates of epiphytes in their representative fresh produce in this study. Shasha market in Ondo has the least number of recovered pathogen, this may be due to the time of samples collections which has fallen to dry season. So many of the marshy floor have dried off, but dust from the environment could contaminate the samples. On the contrary, according to Tsado et al. (2015), fresh produce sold during the dry season have higher microbial load to those sold in open market in wet season.

Cabbage from Mile 12 in Lagos State, Orisunbare in Osun State and Okitipupa in Ondo State had higher percentage of microbial contaminants due to higher percentage of farm produce that come directly from farm to these markets are soild right from farms. It could also be due to inappropriate handling and storage of cold environment during the harvesting, packing, storage, and display at market site (Eni et al, 2010). Cabbage from markets such as Ile-Epo, Oshodi, Lekki, Balogun and Alaba, Oja-Titun Ife, Shasha and Oja-Oba in Owo were fitted for consumption because there was no pathogens recovered from them. Only Shasha has carrot that are acceptable for consumption as at the time of sample collections. This might be due to short holding timing of display.

Furthermore, minimal processing could have occurred after purchases were made to marketers like trimming and little cleaning. Vegetables (cabbage, carrot and cucumber) from this study were observed to have harbored more pathogenic pathogenic epiphytes when compared to the fruits (watermelon and garden egg and tomatoes on VRBG, BGA and XLD Agar). Meanwhile, on PALCAM and OXFORD Agar, garden egg carry the highest microbial level after carrot because both were found coming soiled from farms. This result is in line with that obtained and confirmed by Iveren et al. (2021) The TVC of cabbage were in lower levels because majority of marketer removed the outer layer of cabbage before display for sales or sold out.

No market has contaminated tomato in Lagos State. This might be due to way tomato is transported into Lagos State in a separate basket in order to discourage spoilage and cross-contamination. All samples were gotten from farmers selling in markets so they are not washed samples, for retailers wash tomato before displaying in market while they seperated the bruise ones (Hussein et al., 2020). In this study the bruise fresh produce were not used. Damage surfaces predispose fresh produce to pathogenic microorganisms, causing harm to consumers. Only Ile-Epo market has contaminated garden egg in the whole of Lagos State, this could be as a result of cross contamination in market or right from farm. Majority of garden egg directly from farm are not that soiled unlike other fresh produce like carrot. Brook et al. (2012) evaluated the microbial risk agricultural soil can pose on fresh produce. Moreover, contamination might not only come from agricultural soil but also from irrigation water used, This is in support by Cucumber in all the markets of all the states and Ile-Epo and Oyingbo have contaminated watermelon with epiphytes in Lagos State. These fresh produce were found to be kept on the market soil or warehouse floor.

Lagos State fresh produce were observed to have the lowest microbial contaminants (pathogenic epiphytes) while Osun state has the highest values. This could be as a result of inadequate or poor awareness about food safety in Osun State which is more prominent in Lagos. Aside from this, Ready-for-sale foods could be contaminated via poor agricultural, manufacturing and hygienic practices which drive contamination of fresh produce and thus predispose consumers to food-borne illnesses (Oranusi and Braides, 2012; Oranusi and Oluwafemi, 2011; Afolabi et al., 2012; Odu and Akano, 2012; Akinnibosun and Ojo, 2015). Furthermore, maintaining modified storage atmosphere from the onset of harvesting upto consumers’ table could guarantee supply of fresh produce that are safe and acceptable for consumption (Mohamed et al., 2018; Ibrahim et al., 2011).

Cabbage samples gotten from Lagos, Osun and Ondo with highest value of 2.44 x 10⁴ cfu/g in all the markets revealed that this fresh produce could be route of microbial pathogen which was observed in various studies. Cabbage viable count in Zaria studied by Abdullahi and Abdulkareem (2010) was at the range of 2.1.0x10⁸ while in Ota, Eni et al. (2010) confirmed microbial level of 1.8x10³, Adebayo-Tayo et al. (2012) also reported cabbage with total aerobic count of 1.43 x 10⁶ to 2.10 x 10⁶ cfu/g and total coliform count between 3.10 x 10⁶ and 4.20 x 10⁶cfu/g. About 3.4x10⁵ cfu/g was revealed in cabbage from Umiahia by Nwankwo et al. (2015). Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Erwinia sp., Enterobacter sp., Salmonella sp. and Shigella sp. From carrot gotten from Delta State has 1.83 x 10⁷ to 3.26 x 10⁷cfu/g microbial growth with E. coli (20%), S. auerus (15%) and Shigella sp. (8%).

The recovered pathogenic epiphytes from this study deduce that human activities have a vital role to play in microbial contamination of fresh produce in that higher growing and consumption demand for fruits and vegetables has encourage the supply of many microbial hazardous produce in the markets (Balali et al., 2020). Oyinlola et al. (2017) affirmed that fresh produce are cropped with waste droppings of animals in Lagos State and he recovered high amount of pathogens such as Listeria, E coli, Shigella and Salmonella. David and Odeyemi (2007) had relative higher amount of Listeria monocytogenes from soil with vegetables too in Ado-Ekiti and Negbenebor et al. (2019) had higher microbial load in vegetable salad from Kaduna and Adeleke et al. (2012) examined the microbial contaminants (Citrobacter spp, Pseudomonas aeruginosa, Enterococcus faecalis, Listeria monocytogenes, Staphylococcus aeureus, Bacillius cereus) of 100 fruits from Alekuwodo, Igbonna, Oke-fia, and Orisumbare in Osun State.

Poor hygiene and environmental pollution vary from time to time depending on the both man and animal activities (Ofor et al., 2009). These have been important source of epiphytes in fresh produce from man and animal activities. Contaminated irrigation water, agricultural soil, workers or handlers, uncontrolled storage environment, packing fresh produce together, unhygienic handling of fresh produce, display condition likewise could be versatile driven factors for source of contamination for fruits and vegetables in this study. Thus, only few of the data from this study have acceptable limit rate, for many fresh produce are observed to be contaminated. If one medium showed no growth, another medium from this research work showed reasonable higher amount of microbial contaminant as also observed by Adekanle et al. (2015).

Amidst the pathogens found in this study are Raoultella ornithinolytica, Salmonella spp. Klebsiella pneumonia ssp pneumonia 1, Pasteurella pneumotropica, Serratia liquefacien, Serratia fonticola, Serratia marcescens, Stenotrophomonas maltphilio, Enterobacter cloacae, Pseudomonas luteola, Ochribactnim anthropi, Salmonella ficaria, Cedecae davisae and Cedesae lafagei. Escherichia hermannii, Pantoea spp., Escherichia coli, Leclercia decompoxylata, Klebsiella pneumonia spp ozaenia, Salmonella spp arizonae, Citrobacter braaki, Citrobacter freundii, Salmonella enterica ssp arizonae, Entrobacter aerogenes. Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes, Staphylococcus aureus and Campylobacter spp. are amoung the critical public health importance microorganism, causing food-borne illnesses (Wadamori et al., 2017).

Thus, the occurrence of these organisms in fresh fruits and vegetables which can be eaten with the cover or peel sold in markets in Nigeria may pose risk to consumers. Most of the other bacteria identified in the study are enteric bacteria could have contaminated the fresh produce right from farm (due to irrigation water and agricultural soil, during harvesting, transporting of the produce and also in the market due to unhygienic approach and condition in which the produce were subjected to (Gundappa et al., 2021).

Carrots, cucumber, cabbage and onions were found to have Enterobacter spp. (21.4%), Staphylococcus aureus (14.3%), Erwinia spp. (14.3%) and Pseudomonas spp. (14.3%) (Adebayo-Tayo et al., 2012); while Salmonella spp. (7.1%), Aspergillus niger, Rhizopus stolonifer and Aspergillus fumigatus in Akwa-Ibom in Nigeria (Owolabi, 2013). Ezenwaka and Amuzie (2021) isolated Lactobacillus sp., Proteus mirabilis, Bacillus subtilis, Pseudomonas sp., Bacillus cereus, Salmonella typhi, Shigella sp., Escherichia coli and Staphylococcus aureus in cucumber and garden egg from Bayelsa State, Nigeria, having total viable bacterial count, total coliform count and total Salmonella-Shigella count in cucumber (10.9 ± 4.9×10⁵, 6.47 ± 4.7×10⁵, 7.16 ± 4.9×10⁵ and 1.16 ± 3.2×10⁵) and Garden egg (8.9 ± 6.1×10⁵, 7.37 ± 3.5×10⁵, 4.57 ± 6.6×10⁵ and 1.5 ± 3.2 ×10⁵) respectively.

Total coliforms of tomatoes in Kastina, Kano and Katsina were 5.4, 5.4 and 5.2 Log MPN/g, with E. coli counts from market-sourced tomato samples were 0.9 Log MPN/g, 1.2 Log MPN/g, and 0.7 MPN/g respectively (Shenge et al., 2015). Cucumber (9.5x10⁵), Carrot (8.5x10⁵) and Cabbage (3.4x10⁵); Cucumber (1.3x10³); Carrot (3.0x10³); Cabbage (2.1.0x10³); and cucumber (3.0x10³); Cabbage (3.0x10³); Carrot (2.0x10³) are microbial load of E coli, Staphylococcus aureus, Pseudomonas aeroginosa, Bacillus, Enterobacter, Proteus vulgaris, Proteus mirabilis, Staphylococcus aureus, Pseudomonas aeroginosa, Citrobacter fruendii; and Micrococcus, Pseudomonas, Bacillus, S. aureus studied by Nwankwo et al. (2015), Uzeh et al. (2009) and Oluwafemi et al. (2013) in Umuahia, Lagos and Abeokuta (Ogun). Similarly, Bukar et al. (2010) got E. coli (23.3%), S. typhi (8.3%) and Vibrio cholerae (25%) in tomato (6.00 x 10³ − 1.32 x 10⁷), cabbage (< 30-2.8x10⁸), and carrot (5.60x10³-1.20x10⁵) in Kano. Other work on the safety of fresh produce in Nigeria done are Miyebi et al. (2018); David and Odeyemi (2007); Kabir et al.(2019); Itohan et al. (2011); Adesetan et al. (2013); Erhirhie et al. (2020); Maikai and Akubo (2018); Ajayi et al. (2017). All these supported what w

Minimal or no heat or processing treatment that fresh produce are subjected in makes them to be predisposed to microbial cross contamination or retain the contaminants on them which is capable to cause pandemic outbreak. Other researchers in Nigeria who have worked on microbial quality and safety of fresh produce have confirmed higher level above the acceptable limit. Moreover, pathogens found on fresh produce might not be the only route contaminants could be transferred. Beneficial microorganisms found therein could also carry the gene for pathogenicity. The prevalence of antimicrobial resistant Lactobacillus plantarum TCP 008 (cabbage) and Weissella cibaria PON 10339 (carrot), in both cabbage (32.0%) and carrot (3.0%) from Mile 12, Oshodi and others, assessed by Bamidele et al. (2017) and this can bring about food-borne illness rather than the LAB to inhibit the causable agents. Cabbage (32.0%) and carrot (3.0%) were also seen to carry antimicrobial resistant.

From this study, it was confirmed that freshly harvested fruits and vegetables could be a versatile route of contamination. It was reviewed that isolated microbes could be from irrigation water, dust, agricultural soil, market soil, farmers and sellers activities, fresh produce handlers on farm and in displaying in the markets. packaging, handling and marketing. Time of transporting and marketing could be a risk factor including the temperature and condition of the environment of packing house or ware house.

Moreso, the contaminated fresh produce with epiphytes have capacity to cause gastrointestinal disorders, fever, abdominal cramp, vomiting and diarrhea due to food poisoning.Vegetables were found to harbor more microbial contaminant to fruits. Many of the produce from this study could predispose consumers, even foetus to risk of food poisoning. Hence, carrots were more contaminated when observed on VRBG, BGA and XLD Agar. Garden Egg is more contaminate when evaluated from both PALCAM and Oxford. Tomato were least contaminated. XLD and PALCAM Agar favour grow more than BGA and OXFORD Agar. Lagos State Markets have the least microbial contaminants while Osun State markets reveal the highest microbial pollution. Amidst the market in Lagos, Osun and Ondo State, Mile 12, Igbona and Okitipupa carried the highest contaminants.

From the results of this study, effective recommendations must be implemented. Precaution measure must be taken as one-health approach starting from farm unto consumers’ table. Good marketing, hygienic (environmental or personal). processing and agricultural practices must also be ensured. Some practices (such as untreated manual from both animal and human feces, dumping wastes in water body…) must be prohibited. Adequate education is vital on health, waste management, critical control point, decomposing manure, food safety, food quality, hygienic way to irrigate, harvest, transport, store and display fruits and vegetables in open markets, how to ensure sanitary condition of fruits and vegetables facilities, social media publicity effectiveness and so on. Due to the health risk associated with the consumption of fruits and vegetables in Nigeria, there is need to enforce regulatory agencies and market management authorities that will ensure tendering quality and safe fruits and vegetables from farm to fork.

Furthermore, seperation of bruised or spoilt fruits and vegetables, decontamination of fruits and vegetables by washing even with disinfectant like vinegal and maintenance of storage temperature during transportation, marketing preparation and distribution must be done regularly. Strategy to coordination of movement to consumer and vendors while offloading the truck or during marketing and for safe disposal contaminated fruits and vegetables in the markets must be ensured.

Declaration of Competing Interest

None

Acknowledgement

At NIMR, we thank all staff involved in the development and implementation of this project. Thank you so much.

Funding

None

Data Availability

The data underlying this article are available in the article

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Assessment of Epiphytic Pathogens from Different Media, Associated with some Ready-for-sale Fresh-Fruits and Vegetables in Selected Markets within Southwest Nigeria

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Version 1

Abstract

Figures

Sustainability Statement

1.0 Introduction

2.0 Materials And Methods

2.1 Samples Collection

2.2 Analytical Methods

2.2.1 Isolation, Enumeration and Detection

2.3 Outcome Measure

3.0 Results

3.1 Overview of the Analyzed Marketed Fresh Ready-For-Sale Fruits and Vegetables in Southwest, Nigeria

3.4 Fresh Produce Pathogenic Epiphytes Risk Levels

3.5 Pathogenic Epiphytes Occurrence/Incidence in Fruits and Vegetables

4.0 Discussion

5.0 Conclusion

Declarations

References

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Version 1