In Vitro Selective Antibacterial and Antiproliferative Effects of Ethanolic Extracts from Cambodian and Philippine Plants Used in Folk Medicine for Diarrhea Treatment

Transcriptomic and metabolomic characterization of antibacterial activity of Melastoma dodecandrum

Antibacterial resistance poses a significant global threat, necessitating the discovery of new therapeutic agents. Plants are a valuable source of secondary metabolites with demonstrated anticancer and antibacterial properties. In this study, we reveal that Melastoma dodecandrum exhibits both bacteriostatic and bactericidal effects against Pseudomonas aeruginosa and Staphylococcus aureus. Treatment with plant extracts results in membrane damage and a reduction in P.aeruginosa swimming and swarming motility. A comparative analysis of bacterial transcriptomes exposed to M.dodecandrum extracts and four distinct antibiotics indicates that the extracts may trigger similar transcriptomic responses as triclosan, a fatty acid synthesis inhibitor. Activity-guided fractionation suggests that the antibacterial activity is not attributable to hydrolyzable tannins, but to unidentified minor compounds. Additionally, we identified 104 specialized metabolic pathways and demonstrated a high level of transcriptional coordination between these biosynthetic pathways and phytohormones, highlighting potential regulatory mechanisms of antibacterial metabolites in M.dodecandrum.

Phytochemical and In Vitro Cytotoxic Screening of Chloroform Extract of Ehretia microphylla Lamk

Ehretia microphylla of the Boraginaceae family has been extensively used as a folklore remedy for the treatment of a wide range of ailments such as cough, cancer, allergies, and gastrointestinal and venereal disorders. Extensive literature review reports have revealed these findings due to the presence of numerous phytomolecules. To validate traditional claims for cytotoxic activity of E. microphylla, the present study was undertaken. Dried leaves of the plant were powdered and defatted with petroleum ether followed by hot continuous extraction with chloroform. The chloroform extract was subjected to in vitro cytotoxic screening against a panel of human cancer cell lines such as HCT-116 (colon), MCF-7 (breast), PC-3 (prostate), A-549 (lung), HL-60 (leukemia) and MiaPaCa-2 (pancreatic) at 50 µM using SRB assay. The extract exhibited noteworthy cytotoxicity activity against breast and lung cancer. It exhibited 85.55% and 77.93% inhibition against MCF-7 and A-549 cancer cell lines, respectively. The mechanism behind cell death was determined using the DAPI staining method, which induces alteration in nuclear morphology in MCF-7 cell lines evidenced through DAPI staining. Phytochemical screening of E. microphylla extract showed the presence of saponins, steroids, lipids, tannins and triterpenoids. The chemoprofile of the chloroform extract of E. microphylla leaves was established using an n-hexane:ethyl acetate solvent system in a ratio of 6:4. The developed chromatogram showed five spots both in visible and UV light at 254 nm. The information provided in the present study will enable further studies on the isolation and characterization of bioactive compounds/fractions by following bioactivity-guided fractionation, and thus, the plant has the potential to reduce proliferation and may induce cell death via apoptosis in breast cancer cells.