Carbapenemase-producing Acinetobacter baumannii (A. baumannii) is resistant to most of the available antibiotics and poses serious therapeutic challenges. The study investigated Monsonia angustifolia (M. angustifolia) and Momordica balsamina Linn (M. balsamina Linn) extracts for antibacterial activity against a clinical isolate of carbapenemase-producing A. baumannii using the Kirby Bauer disc diffusion and TLC coupled with bioautography. MIC determination experiments were conducted on a molecularly characterized A. baumannii isolate identified using VITEK2. Positive PCR detection of bla_OXA-51 and bla_OXA-23 confirmed isolate identity and the presence of a carbapenemase-encoding gene. Antibacterial activity was observed with the methanolic extract of M. balsamina Linn with a MIC of 0.5 mg/mL. Compounds with Rf values of 0.05; 0.17; 0.39 obtained from M. angustifolia hexane extract; compounds with Rf values of 0.58; 0.78; 0.36; 0.48; 0.5; 0.56; 0.67; 0.9 obtained from M. angustifolia dichloromethane extract; compounds with Rf values of 0.11; 0.56; 0.24; 0.37 obtained from M. angustifolia acetone extract and compounds with Rf values of 0.11; 0.27 obtained from M. angustifolia methanol extract demonstrated a level of antibacterial activity. M. angustifolia and M. balsamina Linn plant extracts have a clinically significant antibacterial activity against a carbapenemase-producing A. baumannii strain.

Momordica balsamina Linn is a well-known African traditional herb due to its tremendous medicinal and nutritional properties. It is used worldwide for the treatment of different ailments and diseases. In the present study, the phytochemical and antioxidant activity of South African M. balsamina fruit pulp extracts was evaluated. The fruit pulp extracts were obtained by using the serial exhaustive extraction procedure using the solvents hexane, DCM, acetone, and methanol. The resulting extracts were subjected to different standard colorimetric tests for phytochemical analysis. The presence of compounds with antioxidant activity was determined using dot plot and TLC. The DPPH radical scavenging assay, hydrogen peroxide activity, and reducing power assay, coupled with linear regression, were employed to determine the quantity of antioxidants and their IC50. The results for qualitative phytochemical screening have shown that the fruit pulp contains alkaloids, cardiac glycosides, saponins, phenolic compounds, tannins, flavonoids, terpenoids, and steroids. All the extracts revealed the presence of antioxidant activity in both dot plot and TLC. Acetone extracts (0.279 mg/mL) showed the lowest IC50 compared to the standards gallic acid (0.4 mg/mL) and diosgenin (0.42 mg/mL). These findings confirmed that M. balsamina is very rich in phytochemical compounds and has strong antioxidant potential; therefore, it could be a potential source of drugs which in the future may serve the production of synthetically improved therapeutic agents.

Momordica balsamina Linn. is widely used in traditional medicine for the management of diabetes; however, the specific bioactive compounds responsible for this activity have not been fully isolated and structurally elucidated from South African populations. This study reports, for the first time, the isolation and comprehensive characterization of antidiabetic compounds from South African samples of M. balsamina. Crude extracts were obtained through sequential solvent extraction, followed by isolation and purification using vacuum liquid chromatography. Structural elucidation was achieved using HPLC, UPLC–MS, FTIR, and NMR spectroscopy. The antidiabetic potential of the isolated compounds was evaluated through inhibition assays against α-amylase, α-glucosidase, and β-glucosidase. Molecular docking was employed to examine binding interactions with these target enzymes, while cytotoxicity was assessed using the MTT assay against Vero and HEK-293 cell lines. Two compounds, DD26.27 and EAEA1.2, were successfully isolated from dichloromethane and ethyl acetate extracts, respectively. Both compounds demonstrated concentration-dependent inhibition of the tested enzymes. Notably, molecular docking revealed strong binding affinities and favorable interactions with key catalytic residues, surpassing the standard drug acarbose and corroborating the in vitro results. Cytotoxicity studies confirmed that, at lower concentrations, the compounds were non-toxic to the tested cell lines. Collectively, these findings provide novel scientific validation of the traditional use of M. balsamina in South Africa and identify promising lead compounds for further in vivo studies and antidiabetic drug development targeting postprandial hyperglycemia.

Background: Momordica balsamina L. is widely used in traditional medicine for the management of diabetes in South Africa and globally. This study evaluated the in vitro antidiabetic and cytotoxic effects of M. balsamina leaf extracts and identified bioactive compounds potentially responsible for its activity. Methods: Leaves were sequentially extracted using solvents of increasing polarity. Phytochemical composition was determined using standard colorimetric assays, while gas chromatography–mass spectrometry (GC–MS) was employed for compound identification. Antioxidant activity was evaluated using dot blot, DPPH radical scavenging, hydrogen peroxide scavenging, and ferric reducing power assays. Antidiabetic potential was assessed using α-amylase, α-glucosidase, and β-glucosidase inhibitory assays, with acarbose as the reference drug. Cytotoxicity was determined by using the MTT assay on Vero and HEK-293 cell lines. Results: Phytochemical screening revealed alkaloids, flavonoids, terpenoids, saponins, glycosides, and steroids. GC–MS analysis identified compounds associated with antidiabetic activity, including vanillin, 2,4-di-tert-butylphenol, oleic acid, phytol, and hexadecenoic acid. All extracts exhibited antioxidant activity, with the ethyl acetate extract showing the strongest effect. Enzyme inhibition was concentration dependent. The dichloromethane and ethyl acetate extracts showed stronger α-amylase inhibition (IC₅₀ = 0.149 and 0.146 mg/mL) than acarbose (0.209 mg/mL). For α-glucosidase, acarbose showed the highest activity, while extracts displayed moderate inhibition. In β-glucosidase assays, both extracts were more active than acarbose. Both extracts were non-cytotoxic up to 500 µg/mL. Conclusions: These findings support the traditional use of M. balsamina and highlight its potential as a safe source of antidiabetic agents, warranting further investigation.