Matlou Tshepo Divine, Matotoka Mashilo Mash, Mnisi Talita Jessica, Masoko Peter
Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Sovena 0727, South Africa.
Antibiotics (Basel). 2025 Feb 26;14(3):238. doi: 10.3390/antibiotics14030238.
The rise in antibiotic-resistant ESKAPE pathogens, which are responsible for severe and hard-to-treat infections, highlights the urgent need for alternative therapeutic agents. While species in the genus have demonstrated antimicrobial potential, limited research exists on . This study evaluated the phytochemical profiles and antioxidant, antibacterial, and antibiofilm activities of leaf and stem extracts. Acidified acetone and hexane were used for extraction, followed by liquid-liquid fractionation with dichloromethane (DCM), ethyl acetate, and butanol. Phytochemicals were profiled using thin-layer chromatography (TLC), while polyphenolic content and antioxidant activity were determined using colorimetric and DPPH assays, respectively. Antibacterial activity was assessed via bioautography and micro-broth dilution assays. Antibiofilm activities were evaluated using crystal violet staining, and metabolic activity was assessed using tetrazolium salt as a cell viability indicator. Ethyl acetate fractions had the highest phenolic (98.15 ± 9.63 mg GAE/g) and tannin contents (108.28 ± 8.78 mg GAE/g), with strong DPPH scavenging activity (79-90% at 250 µg/mL). DCM extracts had potent antibacterial activity, with a minimum inhibitory concentration (MIC) of 0.31-0.625 mg/mL against , , and . Antibiofilm assays revealed over 50% inhibition across biofilm formation phases, with DCM leaf extracts disrupting biofilms by inhibiting microbial metabolism. This study highlights as a promising source of bioactive compounds with significant antioxidant and antibacterial properties. The DCM and ethyl acetate extracts demonstrated high polyphenol content and effective biofilm inhibition. Further studies are warranted to isolate bioactive compounds and elucidate their mechanisms of action.
对抗生素耐药的ESKAPE病原体数量增加，这些病原体可导致严重且难以治疗的感染，这凸显了对替代治疗药物的迫切需求。虽然该属中的物种已显示出抗菌潜力，但关于……的研究有限。本研究评估了……叶和茎提取物的植物化学特征以及抗氧化、抗菌和抗生物膜活性。使用酸化丙酮和己烷进行提取，随后用二氯甲烷（DCM）、乙酸乙酯和丁醇进行液-液分级分离。使用薄层色谱（TLC）分析植物化学物质，同时分别使用比色法和DPPH测定法测定多酚含量和抗氧化活性。通过生物自显影和微量肉汤稀释试验评估抗菌活性。使用结晶紫染色评估抗生物膜活性，并使用四唑盐作为细胞活力指标评估代谢活性。乙酸乙酯馏分的酚类含量最高（98.15±9.63 mg GAE/g）和单宁含量最高（108.28±8.78 mg GAE/g），具有很强的DPPH清除活性（在250 µg/mL时为79 - 90%）。DCM提取物具有强大的抗菌活性，对……、……和……的最低抑菌浓度（MIC）为0.31 - 0.625 mg/mL。抗生物膜试验显示在生物膜形成阶段的抑制率超过50%，DCM叶提取物通过抑制微生物代谢破坏生物膜。本研究强调……是具有显著抗氧化和抗菌特性的生物活性化合物的有前景来源。DCM和乙酸乙酯提取物显示出高多酚含量和有效的生物膜抑制作用。有必要进一步研究分离生物活性化合物并阐明其作用机制。
