The potentiation of beta-lactam and anti-bacterial activities of lipophilic constituents from Mesua ferrae leaves against methicillin-resistant Staphylococcus aureus.

OBJECTIVES: Mesua ferrae, from the family of Calophyllaceae, is traditionally used for the treatment of piles, fever and renal disorders. The present study was aimed to examine the antibacterial compounds from the leaves of M. ferrae and their ß-lactam antibiotic potentiate activities against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). METHODS: Stigmasterol (1) and ß-caryophyllene oxide (2) were isolated from the n-hexane fraction of the leaves of M. ferrae using a bioassay-guided fractionation approach. RESULTS: The isolated compounds displayed anti-Staphylococcus and anti-MRSA activities. It is worth to note that both compounds demonstrated synergism with ß-lactam antibiotics against S. aureus and MRSA. Gas chromatography-mass spectrometry (GC-MS) analysis indicated the n-hexane fraction was dominated by triterpenes and sesquiterpenes, suggesting the total antibacterial activity exhibited by the fraction. CONCLUSION: Based on the findings, it could conclude that M. ferrae is a promising natural source for the discovery of new anti-MRSA lead compounds.

Polyphenols rich fraction of Dicranopteris linearis promotes fibroblast cell migration and proliferation in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Dicranopteris linearis is a fern used traditionally for the treatment of skin afflictions such as external wounds, boils and ulcers. However, there are no scientific studies to date to demonstrate its ability to induce wound recovery. The objective of the present study was to explore the wound healing properties of an active fraction of D. linearis through several in vitro assays and to determine its chemical profile. MATERIALS AND METHODS: The antioxidant activities were evaluated by DPPH and FRAP assays. The ability of the active fraction to induce fibroblast cell proliferation in serum deprived medium or under the challenge of exogenous hydrogen peroxide was evaluated by MTT assay. Cell migration was investigated using the scratch-wound assay. Chemical constituents of the active fraction were isolated and their structures were determined by NMR and MS spectroscopic techniques. Chemical profiling was carried out by the HPLC-UV method. RESULTS: The fifth subfraction of the methanol extract of D. linearis (sF5) showed prominent antioxidant activities. It was non-cytotoxic at the concentration tested and was able to induce cell proliferation of selected fibroblast cells under serum deprived conditions. In addition, sF5 was found to enhance cell migration and promote cellular repair following oxidative damage caused by hydrogen peroxide through a mechanism which was independent of its hydroxyl radical scavenging capability. Six phenolic glycosides were identified in sF5 where three were known, two were new and one phenolic glycoside first time reported from the plant. CONCLUSION: The active fraction of D. linearis which was rich in polyphenolic substances exhibited substantial antioxidant activities, induced cellular repair and contributed positively to fibroblasts proliferation and migration in vitro. Hence, it may have potential application in inducing wound recovery and supports its ethnopharmacological use for treating skin problems.