Chewing sticks are commonly used as oral hygiene tool in Africa and reactive oxygen species have been linked to the cause of degenerative diseases because of their ability to induce oxidative damage to biological molecules. Plants have been a long source of dietary antioxidants as most plants have been found to exhibit excellent antioxidant potentials. Mezoneuron benthamianum is a plant that is used locally as chewing sticks in southwest, Nigeria, but its use as a therapeutic agent in dental caries, a disease caused by bacteria especially Streptococcus mutans is poorly investigated. This study was therefore designed to investigate the anticaries activities of the crude extracts of M. benthamianum root against four clinical oral pathogens (Staphylococccus aureus, Escherichia coli, Pseudomonas aeruginosa and Streptococcus mutans) and the antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl (DPPH). The results of this study showed that M. benthamianum had a consistent activity against all the bacterial organisms tested, with the ethyl acetate extract having the highest anticaries activity with minimum inhibitory concentration values of 78 and 156 μg/mL, while the hexane extract had the least anticaries activity with MIC values of 2500 μg/ml against S. mutans and E. coli respectively. The results also revealed that the ethyl acetate and aqueous methanol extract exhibited a higher antioxidant activity (IC50 = 23.70 and 21.30 μg/mL) than standard ascorbic acid (IC50 = 38.20 μg/mL). This study demonstrated the anticaries and antioxidant potentials of M.benthamianum and therefore justifies the folkloric use of M. benthamianum in oral hygiene.

中文翻译：

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甲磺脲根瘤菌根提取物对口腔致龋微生物和2,2-二苯基-1-吡啶并肼基（DPPH）清除自由基的抑制作用

咀嚼棒在非洲通常用作口腔卫生工具，而活性氧由于其对生物分子产生氧化性损伤的能力而与退化性疾病的原因有关。植物一直是饮食中抗氧化剂的长期来源，因为已发现大多数植物都具有出色的抗氧化剂潜力。Mezoneuron benthamianum是一种在尼日利亚西南部本地用作口香棒的植物，但在龋齿中却用作治疗剂，而龋齿是由细菌（尤其是变形链球菌）引起的疾病，对此研究很少。因此，本研究旨在研究本氏烟草根的粗提物对四种临床口腔病原体（金黄色葡萄球菌，大肠杆菌，铜绿假单胞菌和变形链球菌）以及使用2,2-二苯基-1-吡咯肼基（DPPH）的抗氧化活性。这项研究的结果表明，本生沙门氏菌对所有测试的细菌具有一致的活性，其中乙酸乙酯提取物具有最高的抗龋活性，最小抑菌浓度分别为78和156μg/ mL，而己烷提取物的抑制活性最低。变异链球菌和大肠杆菌的MIC值分别为2500μg/ ml时的最小防龋活性。结果还显示，乙酸乙酯和甲醇水溶液提取物比标准抗坏血酸（IC50 = 38.20μg/ mL）表现出更高的抗氧化活性（IC50 = 23.70和21.30μg/ mL）。这项研究证明了M.benthamianum的防龋和抗氧化潜力，因此证明了M.