As a flowering plant, Abelmoschus esculentus (L.) Moench (okra or Bamie) belongs to the Malvaceae family. The okra plant is an African-native edible plant that can be planted in many hot and humid or subtropical regions worldwide, such as Southeast Asia and the Mediterranean. In traditional medication, okra treats gastritis typically. Among many pharmacological features, antioxidant, antidiabetic, neuroprotective, anti-fatigue, and antihyperlipidemic activities are mainly highlighted. Also, it is worth noting that the okra plant contains high contents of flavonoids, polyphenols, and polysaccharides. Flavonoids and polyphenols hold robust antioxidant properties[2, 3] and originate from the okra seeds, while its covering extract scarcely showed such responses. Luo et al. (2018) found flavonoids content of 788.56 mg/g in okra flower extract to be the highest compared to other parts using high-performance liquid chromatography (HPLC). Also, the quercetin glucopyranoside content was reported at 122.13 mg/g of the flower extract. Isoquercitrin is one of the frequent-mentioned substances in the okra extract with advanced bioavailability compared to quercetin, demonstrating in vitro and in vivo chemo-protective special effects touching oxidative tensions, allergic responses, cardiovascular syndromes, diabetes, and cancer. Specifically, isoquercitrin can trigger the inhibition of the urinary bladder and the progress of pancreatic tumors[6, 7], along with the suppression of malignant colon cells. In 2021, Peter et al. determined the optimal extraction conditions for extracting high content of polyphenols and flavonoids from okra fruits quantified using the Folin-Ciocalteu and aluminum chloride colorimetric methods respectively. New studies, then, are needed to identify additional polyphenolic compounds and determine their antidiabetic effects.
Using as traditional herbal medicine or food, native communities have been utilized okra fruits as curry, fresh vegetables, aiding digestion, managing gonorrhea, anemia, and urethrorhea, and diabetes mellitus. The excellent source of bioactive compounds in okra fruits and seeds makes it an effective traditional medicine. These phytochemicals were considered volatile oils, glycosides, alkaloids, and polysaccharides polyphenols which are the most prominent and universal secondary metabolites herbal class. Free or sugar-bonded flavonoids such as myricetin and quercetin and its derivatives are also the sub-class of polyphenol isolated from the okra fruits and seeds. The widespread bioactivities of polyphenols with high structural diversity include antioxidant and antidiabetic. According to Shen et al. flavonoids extracted from the okra fruits showed an α-glucosidase and α-amylase inhibitory effect on concentration dependency. Besides, oligomeric proanthocyanidins extraction moiety, active polyphenolic compounds from okra seeds indicated α-glucosidase and α-amylase inhibitory activity. Likewise, phenolic- and flavonoid-rich extraction of okra seeds ensured exceptional antioxidant activity in vitro . At the same time, Myricetin exhibited a plasma glucose concentration decrease and insulin sensitivity improvement in glucose rats with obesity problems. Giving in hand the antidiabetic activity of polyphenolic compounds, it could be supposed that the antidiabetic activity of okra extracts could be due to the presence of these compounds. Then, the diverse action mode of polyphenols with antidiabetic activity could potentially be helpful for type 2 diabetes mellitus due to numerous organs’ participation in its existence.
Regardless of the above studies, the lack of studying the inhibition properties of okra plant extract on enzymes can be sensed. In this study, we aimed to investigate the effects of flavonoids extraction from A. esculentus on α-glucosidase and α-amylase enzymes produced from citrus brown snail (Caucasotachea lencoranea ).