Ethnopharmacological survey, antioxidant and antifungal activity of medicinal plants traditionally used in Baham locality (Cameroon) to treat fungal infections

Invasive fungal infections are important causes of mortality despite advances in antifungal therapy. The aim of this study was collect information on plants used by traditional healers for the treatment of fungal infections in the Baham subdivision (Western region of Cameroon) and to assess the in vitro antifungal and antioxidant potentials of the extracts from the medicinal plants surveyed. The antifungal activity was assessed by the broth micro-dilution method and the antioxidant activity was determined using the free-radical scavenging assays. The extracts for the plants Kotschya strigosa and Eryngium foetidum had potent antifungal activity with minimum inhibitory concentration value of 32 μg/mL against Cryptococcus neoformans. Eugenia gilgii extract had the highest free radical scavenging capacity in 2,2-Diphenyl-1-picrylhydrazyl assay (IC50 of 4.54μg/mL). There is a rich wealth of knowledge and usage of plants by traditional healers for the treatment of fungal infections and further studies should consider isolation of active compounds from the extracts in order to assess the potential for developing new, effective, safe and affordable phytomedicine for the treatment of fungal infections and other pharmacological applications.Keywords: Ethnomedicine; Fungal infections; Antifungal; Antioxidant; Extrac

Antibacterial Activities of Selected Cameroonian Plants and Their Synergistic Effects with Antibiotics against Bacteria Expressing MDR Phenotypes

The present work was designed to assess the antibacterial properties of the methanol extracts of some Cameroonian medicinal plants and the effect of their associations with currently used antibiotics on multidrug resistant (MDR) Gram-negative bacteria overexpressing active efflux pumps. The antibacterial activities of twelve methanol extracts of medicinal plants were evaluated using broth microdilution. The results of this test showed that three extracts Garcinia lucida with the minimal inhibitory concentrations (MIC) varying from 128 to 512 μg/mL, Garcinia kola (MIC of 256 to 1024 μg/mL), and Picralima nitida (MIC of 128 to 1024 μg/mL) were active on all the twenty-nine studied bacteria including MDR phenotypes. The association of phenylalanine arginine β-naphthylamide (PAβN or efflux pumps inhibitor) to different extracts did not modify their activities. At the concentration of MIC/2 and MIC/5, the extracts of P. nitida and G. kola improved the antibacterial activities of some commonly used antibiotics suggesting their synergistic effects with the tested antibiotics. The results of this study suggest that the tested plant extracts and mostly those from P. nitida, G. lucida and G. kola could be used alone or in association with common antibiotics in the fight of bacterial infections involving MDR strains

Ptaeroxylon obliquum leaf extracts, fractions and isolated compounds as potential inhibitors of 15-lipoxygenase and lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophage cells

Ptaeroxylon obliquum is used traditionally to treat inflammatory diseases and related symptoms such as arthritis, rheumatism, fever and headache. The aim of the study was to determine the anti-inflammatory activities of the crude extracts, fractions and isolated compounds from P. obliquum leaves. Nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages and soybean 15-lipoxygenase (15-LOX) inhibitory assays were used to evaluate the anti-inflammatory activity. The acetone crude extracts and fractions had weak 15-LOX inhibitory activity and also had some toxicity against the RAW 264.7 macrophage cells. The three isolated compounds, obliquumol, lupeol and β-amyrin mixture, and eranthin had good 15-LOX inhibitory activity with IC50 values ranging from 7.4 to 13.9 µg/mL which was in the same order as the positive control quercetin (2.1 µg/mL). The high percentage inhibition of NO production by the crude extracts, fractions and isolated compounds appeared to be due to the toxicity to the macrophage cells. Eranthin had the most promising activity with 71.1% inhibition and 89.1% cell viability at a 0.5 µg/mL concentration. The 15-LOX inhibitory activity of obliquumol, lupeol and β-amyrin mixture and eranthin may explain the traditional uses of P. obliquum to treat various inflammatory diseases even though the possibility that the anti-inflammatory activity might still be exerted through other inflammatory mechanisms.The National Research Foundation (NRF) and the University of Pretoria.http://www.elsevier.com/locate/sajbhj2023Paraclinical Science

Synthesis and anticancer activity evaluation of some new 1,2,3,5-tetrazine derivatives attached to benzothiazole moiety

A series of novel tetrazine derivatives, containing benzothiazole framework, were prepared during the coupling reactions of some diazotized 2-aminobenzo[d]thiazole derivatives with p-acetaminophen. Their structures were elucidated based on NMR and MS spectrometry. The anticancer activity and the safety of the synthesized compounds along with the entire precursors were assessed against three human cancer cell lines and a normal cell line. All the synthesized compounds showed selective cytotoxic activity against the cancer cell lines used in comparison to the normal Vero cell line. Their IC50 values varied from 2.02 to 171.67 μM.The Cameroonian Ministry of Higher Education special research allocation, the German Academic Exchange Service (DAAD) and the University of Pretoria.https://www.arkat-usa.org/arkivoc-journalam2023Paraclinical Science

An in vitro study on the potential of selected South African plant extracts to prevent and treat bovine mastitis

DATA AVAILABILIY: All research data in this study are provided in this manuscript.Mastitis is a painful inflammatory condition, commonly resulting from infections caused by Staphylococcus aureus and other pathogens. In this study, antimicrobial, anti-biofilm and anti-quorum sensing activities of selected plants were investigated against Staphylococcus aureus isolates from clinical cases of bovine mastitis. Acetone and ethanol extracts of 15 plants were initially screened for their antimicrobial activities against the commercially available reference strain S. aureus ATCC 29213. Maytenus undata, Maurocenia frangula, Kalanchoe gunniae and Bryophyllum pinnatum had good activities and extracts were tested against six multi-drug resistant S. aureus strains isolated from clinical bovine mastitis cases. The four plants were further analysed for cytotoxicity and anti-quorum sensing activities. Two of the plants with good results were assessed further for anti-biofilm activity. Minimum inhibitory concentration (MIC) values of the extracts against S. aureus isolates ranged from 0.02 to 0.63 mg/mL. Kalanchoe gunniae extracts were the least cytotoxic with extremely promising selectivity index (SI) values ranging from 12 to 25. Significant inhibition of biofilm development against S. aureus mastitis isolates was observed, but extracts were not able to eradicate pre-formed biofilms. Kalanchoe gunniae extracts had the best anti-quorum sensing activity with minimum quorum sensing inhibition concentration (MQSIC) and MIC values of 0.04 mg/mL and 0.63 mg/mL respectively against Chromobacterium violaceum ATCC 12472. Therefore, K. gunniae holds potential for development of a preventative treatment against bovine mastitis.The University of Pretoria.http://www.elsevier.com/locate/sajb2024-01-18hj2023Paraclinical SciencesProduction Animal Studie

Cytotoxicity, nitric oxide and acetylcholinesterase inhibitory activity of three limonoids isolated from Trichilia welwitschii (Meliaceae)

BACKGROUND: Limonoids are highly oxygenated compounds with a prototypical structure. Their occurrence in the plant kingdom is mainly confined to plant families of Meliaceae and Rutaceae. Owing to their wide range of pharmacological and therapeutic properties, this study was aimed at investigating the potential nitric oxide (NO) and acetylcholinesterase (AChE) inhibitory activity and the cytotoxicity of three limonoids: trichilia lactone D5 (1), rohituka 3 (2) and dregeanin DM4 (3), isolated from Trichilia welwitschii C.DC RESULTS: Results indicated that the three limonoids had low cytotoxicity towards Vero cells with LC50 values ranging from 89.17 to 75.82 (μg/L. Compounds (2) and (3) had lower cytotoxicity compared to puromycin and doxorubicin used as reference cytotoxic compounds. Compound (1) (LC50 of 23.55 (μg/L) had good antiproliferative activity against RAW 264.7 cancer cells. At the lowest concentration tested (0.5 μg/mL), compound (2) and (3) released the lowest amount of nitric oxide (2.97 and 2.93 μM, respectively). The three limonoids had anti-AChE activity with IC50 values ranged of 19.13 (μg/L for (1), 34.15 (μg/L for (2) and 45.66 (μg/L for (3), compared to galantamine (IC50 of 8.22 ( g/mL) used as positive control CONCLUSION: The limonoid compounds studied in this work inhibited nitric oxide production in LPS-stimulated macrophages and had anti-AChE activity. Trichilia lactone D5 had potential antiproliferative activity against RAW 264.7 cancer cells. The limonoids had low cytotoxicity towards Vero cells lines. This study provided further examples of the importance of limonoids compounds as potential AChE inhibitors and anti-inflammatory agents targeting the inhibition of NO productio

Antibacterial and antibiotic-potentiation activities of the methanol extract of some cameroonian spices against Gram-negative multi-drug resistant phenotypes

<p>Abstract</p> <p>Background</p> <p>The present work was designed to evaluate the antibacterial properties of the methanol extracts of eleven selected Cameroonian spices on multi-drug resistant bacteria (MDR), and their ability to potentiate the effect of some common antibiotics used in therapy.</p> <p>Results</p> <p>The extract of <it>Cinnamomum zeylanicum</it> against <it>Escherichia coli</it> ATCC 8739 and AG100 strains showed the best activities, with the lowest minimal inhibitory concentration (MIC) of 64 μg/ml. The extract of <it>Dorstenia psilurus</it> was the most active when tested in the presence of an efflux pump inhibitor, phenylalanine Arginine<it>-β-</it> Naphtylamide (PAβN), a synergistic effect being observed in 56.25 % of the tested bacteria when it was combined with Erythromycin (ERY).</p> <p>Conclusion</p> <p>The present work evidently provides information on the role of some Cameroonian spices in the fight against multi-resistant bacteria.</p

Cytotoxicity, nitric oxide and acetylcholinesterase inhibitory activity of three limonoids isolated from Trichilia welwitschii (Meliaceae)

BACKGROUND: Limonoids are highly oxygenated compounds with a prototypical structure. Their occurrence in the plant kingdom is mainly confined to plant families of Meliaceae and Rutaceae. Owing to their wide range of pharmacological and therapeutic properties, this study was aimed at investigating the potential nitric oxide (NO) and acetylcholinesterase (AChE) inhibitory activity and the cytotoxicity of three limonoids: trichilia lactone D5 (1), rohituka 3 (2) and dregeanin DM4 (3), isolated from Trichilia welwitschii C.DC RESULTS: Results indicated that the three limonoids had low cytotoxicity towards Vero cells with LC50 values ranging from 89.17 to 75.82 (μg/L. Compounds (2) and (3) had lower cytotoxicity compared to puromycin and doxorubicin used as reference cytotoxic compounds. Compound (1) (LC50 of 23.55 (μg/L) had good antiproliferative activity against RAW 264.7 cancer cells. At the lowest concentration tested (0.5 μg/mL), compound (2) and (3) released the lowest amount of nitric oxide (2.97 and 2.93 μM, respectively). The three limonoids had anti-AChE activity with IC50 values ranged of 19.13 (μg/L for (1), 34.15 (μg/L for (2) and 45.66 (μg/L for (3), compared to galantamine (IC50 of 8.22 ( g/mL) used as positive control CONCLUSION: The limonoid compounds studied in this work inhibited nitric oxide production in LPS-stimulated macrophages and had anti-AChE activity. Trichilia lactone D5 had potential antiproliferative activity against RAW 264.7 cancer cells. The limonoids had low cytotoxicity towards Vero cells lines. This study provided further examples of the importance of limonoids compounds as potential AChE inhibitors and anti-inflammatory agents targeting the inhibition of NO productio