The main objective of this study is to compare the effectiveness of toothpaste formulations in giving total protection to the oral cavity. So, three important solution properties: surface tension, conductivity, and pH measurements, have been investigated for eight kinds of commercial herbal and non-herbal based toothpaste of Nepal. The study was extended to evaluate the antibacterial efficacy of toothpaste formulations against the Gram-positive bacteria Staphylococcus aureus (S. aureus) and Gram-negative bacteria Escherichia coli (E. coli), and this was done by standard agar well diffusion technique. Amikacin (30 μg/disk) was used as a positive control to compare the antibacterial potency of the investigated toothpaste. The surface tension of all toothpaste formulations increased with the decrease in concentration. However, the conductivity of the formulations decreased with the decrease in concentration. The highest pH of 8.24 was recorded for Dabur Super Salt (DSS) and all values were found to be higher in tap water solutions. All toothpaste formulations showed significant growth inhibition against both S. aureus and E. coli. The overall antibacterial sensitivity of Dabur Red (DR) is higher for S. aureus. The solid material content was found to be highest for Dabur Herbal Gel (DHG) and lowest for Pepsodent (PD). The findings of the present study showed all toothpaste formulations as effective in inhibiting the growth of tested bacterial species. Toothpaste formulations were found slightly alkaline, which favors bacterial growth inhibition. Increasing surface tension and decreasing conductivity value of toothpaste relative to a decrease in concentration favor its desirable cleansing action.

中文翻译：

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尼泊尔不同品牌牙膏的溶液特性及抗菌功效比较研究

本研究的主要目的是比较牙膏配方对口腔提供全面保护的有效性。因此，已经针对尼泊尔的八种商业草本和非草本牙膏研究了三个重要的溶液特性：表面张力、电导率和 pH 值测量。该研究扩展到评估牙膏制剂对革兰氏阳性菌金黄色葡萄球菌 (S. aureus) 和革兰氏阴性菌大肠杆菌 (E.coli) 的抗菌功效，这是通过标准琼脂井扩散技术完成的。阿米卡星（30 μg/盘）用作阳性对照以比较所研究牙膏的抗菌效力。所有牙膏配方的表面张力都随着浓度的降低而增加。然而，配方的电导率随着浓度的降低而降低。达布尔超级盐 (DSS) 的最高 pH 值记录为 8.24，并且发现自来水溶液中的所有值都更高。所有牙膏配方均显示出对金黄色葡萄球菌和大肠杆菌的显着生长抑制。Dabur Red (DR) 对金黄色葡萄球菌的总体抗菌敏感性更高。发现 Dabur Herbal Gel (DHG) 的固体物质含量最高，而 Pepsodent (PD) 的固体物质含量最低。本研究的结果表明，所有牙膏配方均能有效抑制受试细菌的生长。牙膏配方呈弱碱性，有利于抑制细菌生长。