Pharmacognostical, Phytochemical, In vitro Anti-obesity Studies, and Toxicity Analysis of Momordica charantia Linnaeus Fruits from Haryana

Abstract

Background: Momordica charantia Linnaeus (Cucurbitaceae family), known as bitter melon is an annual climbing vine, which grows in tropical regions and its fruits are consumed as a vegetable in Asian countries. Traditionally various parts of the plant such as fruits, seeds, leaves, flowers, etc. have been used for medicinal purposes. Its fruit is used as an anti-diabetic, laxative, anthelmintic, emetic, and anti-obesity, for respiratory problems, ulcers, wounds, rheumatism, gout, toothache, and skin diseases. Objective: To perform pharmacognostical evaluation, qualitative and quantitative phytochemical screening, safety and toxicity studies, and in vitro anti-obesity activity evaluation on bitter gourd fruits from Haryana (India). Methods: Organoleptic studies were performed with the naked eye and microscopical studies were performed using the EVOS microscope; physicochemical evaluation, microbial, and mycotoxin studies were performed by adopting the standard procedures detailed in the WHO guidelines (2011); phytochemical screening was performed by following the standard procedures; pesticide residue determination was performed by using GCMS; and in vitro anti-obesity evaluation consisting of in vitro pancreatic lipase, α-amylase, and α-glucosidase evaluation was performed by following the standard procedures. Results: The pharmacognostical standards i.e. macroscopy, microscopy, and physicochemical analyses of the fruits were established and their qualitative and quantitative phytochemical contents revealed the presence of alkaloids, glycosides, flavonoids, tannins, proteins, and amino acids, carbohydrates, fats, and fixed oils, sterols, and triterpenoids, etc. The fruit was found to be free from mycotoxin, microbial contamination, and harmful pesticide residues. The major pesticides found to be present in fruit extract were alpha-BHC, Aldrin, 4, 4’-DDE, Endrin, and4, 4'- DDD and they were present within permissible limits. The total phenolic content in the fruits was found to be 3.49 ± 1.3mg/g gallic acid equivalent/100g. The content of total flavonoids have been expressed as quercetin, catechin, and rutin equivalents, i.e., 1.88 ± 0.16, 122.7 ± 13.8 and 1.978 ± 0.006 mg/g dry weight of fruits respectively and they were present within permissible limits. The α-glucosidase inhibition potential of the alcoholic extract was good with an IC50 value of 173.50 ± 0.33 μg/ml, followed by aqueous extract i.e. 351.00 ± 0.56, whereas the chloroform extract showed milder inhibition with IC50 value of 448.60 ± 0.98 μg/ml. The lipase inhibition potential of aqueous extracts was good with an IC50 value of 140.31 ± 0.48μg/ml, followed by alcoholic extracts, with inhibition of 100.10 μg/ml, whereas the chloroform extracts show lesser inhibition, i.e., 499.83 μg/ml only. Whereas the alcoholic extract shows good α-amylase enzyme inhibition with IC50 value of 425.44 ± 0.63 μg/ml, followed by aqueous extract i.e., 486.12 ± 0.77 μg/ml, and chloroform extract shows lesser activity, i.e., 65. 82 ± 0.41 μg/ml. Conclusion: Identification and authentication of the fruits was performed with the help of pharmacognostical and physicochemical standards, and they could be useful for the monograph preparation of the plant and in controlling the commercial adulteration of the bitter gourd fruits. Safety and toxicity studies have determined that the fruits were fit for consumption. In vitro anti-obesity evaluation findings can be further explored in vivo for testing their therapeutic efficacy in lab animals. Proper identification of the crude drug helps the researchers in reproducing the results and carrying the research forward without wasting time that usually occurs due to misidentification of the crude drug which makes lab results difficult to reproduce.