L.N. Tatsadjieu

Bio: L.N. Tatsadjieu is an academic researcher. The author has contributed to research in topics: Bark (sound) & Chemistry. The author has an hindex of 1, co-authored 1 publications receiving 134 citations.

Fungal diversity and occurrence of Aflatoxin B1 , Citrinine and Ochratoxin A in rice of Cameroon

Abstract: Rice is an important cereal for Cameroon where 95% of the population consumes it frequently. To ensuring a healthy food supply to consumers, the objective of this study was to determine the fungal profile and quantify mycotoxins in 12 rice samples produced in Cameroon. The relative density of the different fungal species identified in all of the rice samples revealed the dominance of three fungal genera (Aspergillus, Penicillium, and Fusarium) and 15 fungal species with the predominance of the species Mucor hiemalis (14.56%), followed by Penicillium expansum (13.59%) and Aspergillus versicolor (12.62%). At least one mycotoxin was detected in 83.33% of the samples analyzed, while 41.67% showed co-contamination with at least two mycotoxins. The prevalence of OTA, AFB1, and CIT was 41.67%, 58.33%, and 41.67%, respectively, with concentrations not exceeding those prescribed by European Commission. This study provides useful information for the management of mycotoxinogenic molds in Cameroonian rice. Practical applications The sanitary quality of the rice must be preserved during storage, because several factors (relative humidity, temperature, etc.) can promote the appearance of mycotoxins in the rice and a loss of its organoleptic properties. The practical application of this study is to provide information on the health or toxicological risks presented by certain rice marketed and consumed in Cameroon, particularly with regard to fungal contamination rates, the fungal flora present, and mycotoxin levels.

Formulation, Quality and Antimicrobial Activity of Ointments and Soaps Based on the Bark Extracts of Ziziphus mauritiana and Ziziphus mucronata

Abstract: This study aimed to evaluate the quality and antimicrobial activity of soaps and ointments enriched with aqueous ethanol extracts from barks of Ziziphus mauritiana and Ziziphus mucronata. The galenic formulation allowed the development of ointments as well as soap based on aqueous ethanol extract (70%, v/v) using some excipients. The consistency of the ointments was slightly hard but softens immediately on contact with the skin. The preparation method allowed to get a very good homogeneity with a regular distribution of the extracts. The ointments were stable and no changes on the surface was observed. The ointments were found slight acidic, with pH values varying from 5 to 5.59. It was noticed that enriched soaps displayed neutral pH values neutral varying from 7.28 to 7.49. Moreover, the soap enriched with Z. mauritiana (84%) was more foaming in saline environment than that enriched with Z. mucronata (61.53%). Both bark extract-enriched ointments and soaps displayed excellent antimicrobial activity against fungi and bacteria found on the skin and hands.

Potential of Cameroonian plants and derived products against microbial infections: a review.

Abstract: In Cameroon, infectious diseases are amongst the most commonly notified diseases and largest cause of mortality. Many plants are used locally in traditional medicine for their treatment. The aim of the present review is to summarize currently available evidence and knowledge concerning Cameroonian plants used to treat bacterial and fungal infections, and the efficacy of plant-derived extracts and compounds. The traditional uses of plants in the treatment of infectious diseases have been collected and tabulated. The antimicrobial activity of the extracts and the chemical constituents of most of these plants are summarized in this report. Plants used traditionally in Cameroonian medicine, with laboratory work on any part or products, have been documented. Numerous extracts and compounds have been tested for antimycobacterial, antibacterial and antifungal efficacy and some of them were significantly active. Most of the bioactive compounds isolated were phenolics and alkaloids. In conclusion, many plant species are used in traditional medicine in Cameroon to treat infectious diseases, and several interesting openings have originated for further inquiry following IN VITRO antimicrobial activity evaluation. However, much work is still to be done to standardize methods and cut-off points for describing the antimicrobial activity, and on the study of the mechanisms of action.

Composition and antioxidant activity of the essential oils of Xylopia aethiopica (Dun) A. Rich. (Annonaceae) leaves, stem bark, root bark, and fresh and dried fruits, growing in Ghana.

Abstract: The chemical composition of the essential oils obtained from the leaves, the barks of the stem and the root, as well as from the fresh and dried fruits of Xylopia aethiopica, growing in Ghana, was investigated by gas chromatography/mass spectrometry analyses. Kovats indices, mass spectra, and standard compounds were used to identify a total of 93 individual compounds. The monoterpene hydrocarbons formed the main portion in all studied samples. β-Pinene was predominant in all cases, while trans-m-mentha-1(7),8-diene was the main compound in the essential oils of the leaves and the barks of roots and stems. Their potential antioxidant activity was also investigated and found to be significant in scavenging superoxide anion radical. Keywords: Xylopia aethiopica; Ghana; volatile constituents; leaves; fruits; stem bark; root bark

Natural Product Interventions for Chemotherapy and Radiotherapy-Induced Side Effects.

Abstract: Cancer is the second leading cause of death in the world. Chemotherapy and radiotherapy are the common cancer treatments. However, the development of adverse effects resulting from chemotherapy and radiotherapy hinders the clinical use, and negatively reduces the quality of life in cancer patients. Natural products including crude extracts, bioactive components-enriched fractions and pure compounds prepared from herbs as well as herbal formulas have been proved to prevent and treat cancer. Of significant interest, some natural products can reduce chemotherapy and radiotherapy-induced oral mucositis, gastrointestinal toxicity, hepatotoxicity, nephrotoxicity, hematopoietic system injury, cardiotoxicity, and neurotoxicity. This review focuses in detail on the effectiveness of these natural products, and describes the possible mechanisms of the actions in reducing chemotherapy and radiotherapy-induced side effects. Recent advances in the efficacy of natural dietary supplements to counteract these side effects are highlighted. In addition, we draw particular attention to gut microbiotan in the context of prebiotic potential of natural products for the protection against cancer therapy-induced toxicities. We conclude that some natural products are potential therapeutic perspective for the prevention and treatment of chemotherapy and radiotherapy-induced side effects. Further studies are required to validate the efficacy of natural products in cancer patients, and elucidate potential underlying mechanisms.

Antibacterial activities of selected Cameroonian spices and their synergistic effects with antibiotics against multidrug-resistant phenotypes

Abstract: The emergence of multi-drug resistant (MDR) phenotypes is a major public health problem today in the treatment of bacterial infections. The present study was designed to evaluate the antibacterial activities of the methanol extracts of eleven Cameroonian spices on a panel of twenty nine Gram negative bacteria including MDR strains. The phytochemical analysis of the extracts was carried out by standard tests meanwhile the liquid micro-broth dilution was used for all antimicrobial assays. Phytochemical analysis showed the presence of alkaloids, phenols and tannins in all plants extracts. The results of the antibacterial assays indicated that all tested extracts exert antibacterial activities, with the minimum inhibitory concentration (MIC) values varying from 32 to 1024 μg/ml. The extracts from Dichrostachys glomerata, Beilschmiedia cinnamomea, Aframomum citratum, Piper capense, Echinops giganteus, Fagara xanthoxyloides and Olax subscorpioidea were the most active. In the presence of efflux pump inhibitor, PAsN, the activity of the extract from D. glomerata significantly increased on 69.2% of the tested MDR bacteria. At MIC/5, synergistic effects were noted with the extract of D. glomerata on 75% of the tested bacteria for chloramphenicol (CHL), tetracycline (TET) and norfloxacin (NOR). With B. cinnamomea synergy were observed on 62.5% of the studied MDR bacteria with CHL, cefepime (FEP), NOR and ciprofloxacin (CIP) and 75% with erythromycin (ERY). The overall results provide information for the possible use of the studied extracts of the spices in the control of bacterial infections involving MDR phenotypes.