Phytochemical constituents and antimicrobial evaluation towards development of bioactive herbal formulation from Phyllanthus englerii Pax leaf extracts for potential topical application against selected microbes

Abstract

Abstract Background Atopic dermatitis (AD), a disease often associated with pathogenic microbes, affects around 1.5 million people worldwide each year, with its treatment being complicated by rising antimicrobial resistance. This work reports on phytoconstituents and antimicrobial activities towards developing bioactive herbal formulations from Phyllanthus englerii Pax ethyl acetate leaf extracts to address AD-related infections. Methods The extracts were obtained through cold maceration and phytochemical groups were screened using chemical methods followed by GC-MS and LC-MS analysis to reveal key compounds. The extract and formulated products were tested for antimicrobial activities against selected microbes and screened for toxicity using brine shrimp larvae lethality assay. The formulated products were further evaluated for stability and other physicochemical properties over 28 days. Results The classes of compounds identified therefrom include alkaloids, phenols, cardiac glycosides, steroids, tannins, and terpenoids, of which the presence of 17 phytochemicals, dominated by neophytadiene, squalene, phytol, astragalin, myricitrin, and phlorizin were confirmed. The extract exhibited antimicrobial activity against Staphylococcus aureus , Escherichia coli , and Candida albicans with MIC values of 5.83, 3.75, and 5.00 mg/mL, respectively. The extract indicated low toxicity (LC 50 = 125.50 µg/mL). A jelly-based herbal formulation demonstrated effective inhibition zones ranging from 8.00 ± 0.44 to 17.00 ± 1.25 mm across all tested pathogens, with a jelly formulation (JPEA2, 6.24%) showing the most significant activity, particularly against C. albicans . The formulations maintained favorable stability and other physicochemical properties over 28 days. Conclusion These findings indicate the potential of the developed jelly-herbal formulation as an alternative treatment agent for microbial infections associated with AD.