Antibiotic-potentiation, antioxidant, cytotoxic, anti-inflammatory and anti-acetylcholinesterase potential of Antidesma madagascariense Lam. (Euphorbiaceae)

摘要

Antidesma madagascariense Lam. (AM) is used in the treatment and management of a panoply of human diseases.Leaf decoction, acetone extracts and fractions of AM were evaluated for antimicrobial, antioxidant,anti-inflammatory, cytotoxicity and acetylcholinesterase (AChE) inhibitory activity. The antibiotic potentiatingactivity of crude acetone extract (AE) was assessed against ATCC bacterial strains of Escherichia coli ATCC25922, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923 using standard antibiotics.Decoction extract showed significant inhibitory activity against Acinetobacter spp. (MIC: 0.25 mg/mL) whichhad higher inhibitory effect compared to the positive control Streptomycin (MIC: 1.00 mg/mL). Acetone and decoctionextracts inhibited the growth of Candida albicans (MIC: 4.00 mg/mL). All fractions of AE showed broadspectrum activity against ATCC and clinical strains (MIC 0.03–4.00 mg/mL). The results of the combination pro-files of the AE with Ciprofloxacin, Chloramphenicol and Streptomycin revealed synergistic interactions (FICI ≤0.50) against P. aeruginosa. Crude decoction, acetone extract and fractions were found to be potent reducingagent as well DPPH radical scavenger and ABTS cation scavenger. A significant correlation between DPPH,ABTS and total phenolic content (p b 0.05, r=−0.75 and −0.82 respectively) was recorded. Three fractions namelyDCM:MeOH (85:15) (F5), DCM:MeOH (95:05) (F3) and DCM (F2) [IC50 0.02–0.09 mg/mL] demonstrated significantanti-inflammatory activity as compared to the positive control, diclofenac sodium [IC50 0.18 (0.10–0.31) mg/mL]. AEand its fractions showed AChE inhibitory activities at an IC50 of 35.92–492.6 μg/mL. Cytotoxicity study against Verocells revealed that AE and hexane fraction were non-cytotoxic while decoction showed cytotoxic effect. Furtherstudies are required to explore the potential of AM crude extracts and fractions as natural source of antimicrobial,antioxidant, anti-inflammatory agents as well as AChE inhibitors.