Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014, Finland.
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology Owerri, P.M. B 1526 Owerri, Imo state, Nigeria.
J Ethnopharmacol. 2019 Jan 30;229:157-166. doi: 10.1016/j.jep.2018.10.005. Epub 2018 Oct 15.
Piper guineense occurs commonly in West Africa where it is used for fungal infections instead of the costly and not always accessible conventional antifungals. Fungal, yeast-based diseases are common in West-Africa especially among those living with HIV/AIDS, and thus this study was performed in Imo state, South-Eastern Nigeria, where P. guineense is predominantly used for the treatment of fungal diseases, such as skin rashes, oral thrush and vaginosis.
The scarce number of previous studies on the documentation of the traditional uses of P. guineense extracts for the treatment of fungal infections in Nigeria prompted this survey. The investigation focused on how traditional healers recognize and diagnose fungal infections, how P. guineense is collected, on the various parts used for the treatments, methods of preparations, administrations and treatments. In addition, an in vitro antifungal screening of P. guineense fruit and leaf extracts of various polarities, and piperine and piperlongumine, representing the main constituents in these extracts, were performed.
A house to house ethnobotanical survey was conducted using questionnaires. Twenty traditional medical practitioners (TMP) and herb sellers from ten villages were interviewed. Four human pathogenic strains of yeast and Cryptococcus neoformans, a yeast-like basidiomycete causing meningitis in immunocompromised individuals, were used for the antifungal screening.
The traditional medical practitioners (TMP) and herb sellers explained that the leaves and fruits are the most commonly used plant parts for the treatments. The oral intake of the extracts in locally produced bamboo alcohol (Kai-kai) is the most common method of administration. In accordance with these recorded traditional uses, we found that extracts of P. guineense were growth inhibitory against the fungal strains with MIC values ranging from 39 to 2500 µg/mL. The lowest MIC value of 39 µg/mL was recorded for a methanol fruit extract against Candida albicans, C. glabrata and C. tropicalis. In addition, ethanol and hexane fruit extracts were effective against the growth of C. albicans and C. glabrata, respectively, with a MIC of 78 µg/mL. Piperlongumine and piperine were active against C. albicans with MIC values of 39 and 78 µg/mL respectively.
P. guineense fruit and leaf extracts, as well as their piperamide alkaloid constituents piperine and piperlongumine, have interesting antifungal properties and could have potential as new antifungal scaffolds. Our results warrant further in-depth investigations to isolate and characterize piperamide alkaloids and other compounds responsible for the antifungal activity in the extracts.
在西非，Piper guineense 很常见，那里将其用于真菌感染的治疗，而不是使用昂贵且并非总是可获得的传统抗真菌药物。真菌、酵母类疾病在西非很常见，尤其是在艾滋病毒/艾滋病感染者中，因此，本研究在尼日利亚东南部的伊莫州进行，那里普遍使用 P. guineense 治疗真菌病，如皮疹、口腔鹅口疮和阴道炎。
在尼日利亚，先前关于 P. guineense 提取物治疗真菌感染的传统用途的研究数量很少，这促使了这项调查。该研究的重点是传统治疗师如何识别和诊断真菌感染，P. guineense 如何采集，用于治疗的不同部位，制剂方法，给药和治疗方法。此外，还对 P. guineense 果实和叶提取物的不同极性以及胡椒碱和荜茇酰胺这两种主要成分进行了体外抗真菌筛选。
采用问卷调查法进行家庭式民族植物学调查。对来自十个村庄的 20 名传统医学从业者（TMP）和草药卖家进行了访谈。使用四种人类致病性酵母和新型隐球菌，一种引起免疫功能低下个体脑膜炎的酵母样担子菌，进行抗真菌筛选。
传统医学从业者（TMP）和草药卖家解释说，叶子和果实是最常用的植物部位进行治疗。口服局部生产的竹子酒精（Kai-kai）中的提取物是最常见的给药方法。根据这些记录的传统用途，我们发现 P. guineense 的提取物对真菌菌株具有生长抑制作用，最低抑菌浓度（MIC）值范围为 39 至 2500μg/ml。甲醇果实提取物对白色念珠菌、近平滑念珠菌和热带念珠菌的最低 MIC 值为 39μg/ml。此外，乙醇和正己烷果实提取物分别对白色念珠菌和近平滑念珠菌的生长有效，MIC 值分别为 78μg/ml。荜茇酰胺和胡椒碱对白色念珠菌均有活性，MIC 值分别为 39 和 78μg/ml。
P. guineense 果实和叶提取物及其哌酰胺生物碱成分胡椒碱和荜茇酰胺对真菌具有有趣的抗菌特性，可能具有作为新型抗真菌支架的潜力。我们的研究结果表明，需要进一步进行深入研究，以分离和鉴定负责提取物抗真菌活性的哌酰胺生物碱和其他化合物。
