Medical Microbiology and Molecular Biology Laboratory, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India.
PLoS One. 2012;7(7):e40319. doi: 10.1371/journal.pone.0040319. Epub 2012 Jul 5.
The present study was focused on evaluating the potential of Emblica officinalis against cariogenic properties of Streptococcus mutans, a causative microorganism for caries. The effect of crude extract and ethanolic fraction from Emblica officinalis fruit was analysed against S. mutans. The sub-MIC concentrations of crude and ethanolic fraction of E. officinalis were evaluated for its cariogenic properties such as acid production, biofilm formation, cell-surface hydrophobicity, glucan production, sucrose-dependent and independent adherence. Its effect on biofilm architecture was also investigated with the help of confocal and scanning electron microscopy (SEM). Moreover, expression of genes involved in biofilm formation was also studied by quantitative RT- PCR. This study showed 50% reduction in adherence at concentrations 156 µg/ and 312.5 µg/ml of crude extract and ethanolic fraction respectively. However, the biofilm was reduced to 50% in the presence of crude extract (39.04 µg/ml) and ethanolic fraction (78.08 µg/ml). Furthermore, effective reduction was observed in the glucan synthesis and cell surface hydrophobicity. The qRT-PCR revealed significant suppression of the genes involved in its virulence. Confocal and scanning electron microscopy clearly depicted the obliteration of biofilm structure with reference to control. Hence, this study reveals the potential of E. officinalis fruit extracts as an alternative and complementary medicine for dental caries by inhibiting the virulence factors of Streptococcus mutans.
本研究旨在评估余甘子对变形链球菌（龋齿的致病微生物）致龋特性的潜在作用。分析了余甘子果实的粗提取物和乙醇提取物对变形链球菌的作用。评估了粗提取物和乙醇提取物的亚最小抑菌浓度对其致龋特性的影响，如产酸、生物膜形成、细胞表面疏水性、葡聚糖产生、蔗糖依赖和非依赖粘附。还借助共聚焦和扫描电子显微镜（SEM）研究了其对生物膜结构的影响。此外，还通过定量 RT-PCR 研究了与生物膜形成相关的基因表达。本研究表明，在浓度为 156 µg/ml 和 312.5 µg/ml 的粗提取物和乙醇提取物中，粘附减少了 50%。然而，在粗提取物（39.04 µg/ml）和乙醇提取物（78.08 µg/ml）存在下，生物膜减少到 50%。此外，葡聚糖合成和细胞表面疏水性也得到了有效降低。qRT-PCR 显示其毒力相关基因受到显著抑制。共聚焦和扫描电子显微镜清楚地描绘了生物膜结构的破坏，与对照相比。因此，本研究揭示了余甘子果实提取物作为一种替代和补充性药物治疗龋齿的潜力，通过抑制变形链球菌的毒力因子。
