Abstract The stingless bee Heterotrigona itama honey is generating interest among consumers due to unique antibacterial properties. Despite the substantial health benefits of this honey, its action mode of inhibiting and killing pathogenic bacteria remains unresolved. The present study aimed to unravel the effect of raw H. itama honey against four clinically important bacteria, Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus. Total phenolic and total flavonoid contents, alongside antioxidant and antibacterial activities of honey samples were established to identify the ‘best’ raw honey. Honey Sy-1 showing the highest amount of phenolics (80.71 mg GAE/100 g) and antioxidant capacity (82.67%) and, the lowest MIC (1.56% (w/v)) and MBC (3.125% (w/v)), was tested against four bacterial cells, wherein any alterations in cellular morphology were observed under scanning electron microscope. The micrographs revealed significant elongation/filamentation in B. subtilis cells, de-flagellation in P. aeruginosa, membrane perturbation and leakage of intracellular contents in E. coli alongside non-dividing septated cells in S. aureus. H. itama honey inhibited bacterial growth by disrupting the cell membrane in conjunction to interacting with a cytosolic target or possibly interrupted septum formation and blocking DNA and protein syntheses. The evidence strongly supported the natural antibacterial properties of the H. itama honey.

中文翻译：

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暴露于最低抑制和杀菌浓度的生马来西亚无刺蜂蜂蜜的革兰氏阳性菌和革兰氏阴性菌的形态学改变

摘要 由于独特的抗菌特性，无刺蜂 Heterotrigona itama 蜂蜜正在引起消费者的兴趣。尽管这种蜂蜜具有显着的健康益处，但其抑制和杀死病原菌的作用模式仍未得到解决。本研究旨在阐明未加工的 H. itama 蜂蜜对四种临床上重要的细菌、大肠杆菌、铜绿假单胞菌、枯草芽孢杆菌和金黄色葡萄球菌的作用。确定了蜂蜜样品的总酚和总黄酮含量，以及抗氧化和抗菌活性，以确定“最好的”生蜂蜜。蜂蜜 Sy-1 显示出最高的酚类物质 (80.71 毫克 GAE/100 克) 和抗氧化能力 (82.67%) 以及最低的 MIC (1.56% (w/v)) 和 MBC (3.125% (w/v)) ，针对四种细菌细胞进行了测试，其中在扫描电子显微镜下观察到细胞形态的任何改变。显微照片显示枯草芽孢杆菌细胞显着伸长/成丝，铜绿假单胞菌脱鞭毛，大肠杆菌中的膜扰动和细胞内内容物泄漏，以及金黄色葡萄球菌中的非分裂分隔细胞。H. itama 蜂蜜通过破坏细胞膜与细胞溶质靶标相互作用或可能中断隔膜形成并阻断 DNA 和蛋白质合成来抑制细菌生长。证据强烈支持 H. itama 蜂蜜的天然抗菌特性。大肠杆菌中的膜扰动和细胞内内容物的泄漏以及金黄色葡萄球菌中的非分裂分隔细胞。H. itama 蜂蜜通过破坏细胞膜与细胞溶质靶标相互作用或可能中断隔膜形成并阻断 DNA 和蛋白质合成来抑制细菌生长。证据强烈支持 H. itama 蜂蜜的天然抗菌特性。大肠杆菌中的膜扰动和细胞内内容物的泄漏以及金黄色葡萄球菌中的非分裂分隔细胞。H. itama 蜂蜜通过破坏细胞膜与细胞溶质靶标相互作用或可能中断隔膜形成并阻断 DNA 和蛋白质合成来抑制细菌生长。证据强烈支持 H. itama 蜂蜜的天然抗菌特性。