The assessment of risk factors, lipid profile, uric acid and alanine aminotransferase in Helicobacter pylori-positive subjects

Background: Helicobacter pylori infection is associated with gastro duodenal ulcer, chronic gastric, MALT lymphoma and gastric cancer but also to coronary heart diseases, ischemic diseases and metabolic diseases like diabetes. The colonization of the stomach by H. pylori causes persistent inflammation of the stomach wall which can influence some biochemical parameters in the patient. The aim of this study was to investigate risk factors, uric acid and alanine aminotransferase along with lipid parameters in H. pylori-positive and -negative patients at Dschang District Hospital in Cameroon.Methods: A cross-sectional study was carried out on 160 consenting patients of average age 53.91±13.36 years attending the hospital for medical check-up or admitted in the hospital. The determination of anti-H. pylori IgG by the indirect enzyme-linked immunosorbent assay (ELISA) technique, enabled us to distinguish two groups of patients. A questionnaire survey was administered to study participants and potential risk factors for H. pylori exposure sought. Measurements of total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, uric acid and activity of alanine aminotransferase were carried out in serum by methods resulting from commercial kits.Results: The habits of not washing hands after the toilets (OR = 3.33; p = 0.036) and giving of chewed food by the parents to children (OR = 2.26; p = 0.029) were independent risk factors of H. pylori infection. H. pylori infected patients had increased levels of uric acid (p = 0.017), total cholesterol (p = 0.001), LDL-cholesterol (p = 0.021) and total cholesterol/HDL-cholesterol ratio (p = 0.046) compared to the uninfected group.Conclusions: Our study therefore suggests that H. pylori infection can cause modifications of lipid parameters and uremia that are considered as risk factors for cardiovascular diseases and gout.

Anticancer and antibacterial secondary metabolites from the endophytic fungus Penicillium sp. CAM64 against multi-drug resistant Gram-negative bacteria.

Background: The emergence of multiple-drug resistance bacteria has become a major threat and thus calls for an urgent need to search for new effective and safe anti-bacterial agents. Objectives: This study aims to evaluate the anticancer and antibacterial activities of secondary metabolites from Penicillium sp. , an endophytic fungus associated with leaves of Garcinia nobilis . Methods: The culture filtrate from the fermentation of Penicillium sp. was extracted and analyzed by liquid chromatography\u2013 mass spectrometry, and the major metabolites were isolated and identified by spectroscopic analyses and by comparison with published data. The antibacterial activity of the compounds was assessed by broth microdilution method while the anticancer activity was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Results: The fractionation of the crude extract afforded penialidin A-C (1-3), citromycetin (4), p-hydroxyphenylglyoxalaldoxime (5) and brefelfin A (6). All of the compounds tested here showed antibacterial activity (MIC = 0.50 \u2013 128 \u3bcg/mL) against Gramnegative multi-drug resistance bacteria, Vibrio cholerae (causative agent of dreadful disease cholera) and Shigella flexneri (causative agent of shigellosis), as well as the significant anticancer activity (LC50 = 0.88 \u2013 9.21 \u3bcg/mL) against HeLa cells. Conclusion: The results obtained indicate that compounds 1-6 showed good antibacterial and anticancer activities with no toxicity to human red blood cells and normal Vero cells

Antimicrobial and antioxidant activity of kaempferol rhamnoside derivatives from Bryophyllum pinnatum

Abstract Background Bryophyllum pinnatum (Lank.) Oken (Crassulaceae) is a perennial succulent herb widely used in traditional medicine to treat many ailments. Its wide range of uses in folk medicine justifies its being called "life plant" or "resurrection plant", prompting researchers' interest. We describe here the isolation and structure elucidation of antimicrobial and/or antioxidant components from the EtOAc extract of B. pinnatum. Results The methanol extract displayed both antimicrobial activities with minimum inhibitory concentration (MIC) values ranging from 32 to 512 μg/ml and antioxidant property with an IC50 value of 52.48 μg/ml. Its partition enhanced the antimicrobial activity in EtOAc extract (MIC = 16-128 μg/ml) and reduced it in hexane extract (MIC = 256-1024 μg/ml). In addition, this process reduced the antioxidant activity in EtOAc and hexane extracts with IC50 values of 78.11 and 90.04 μg/ml respectively. Fractionation of EtOAc extract gave seven kaempferol rhamnosides, including; kaempferitrin (1), kaempferol 3-O-α-L-(2-acetyl)rhamnopyranoside-7-O-α-L-rhamnopyranoside (2), kaempferol 3-O-α-L-(3-acetyl)rhamnopyranoside-7-O-α-L-rhamnopyranoside (3), kaempferol 3-O-α-L-(4-acetyl)rhamnopyranoside-7-O-α-L-rhamnopyranoside (4), kaempferol 3-O-α-D- glucopyranoside-7-O-α-L-rhamnopyranoside (5), afzelin (6) and α-rhamnoisorobin (7). All these compounds, except 6 were isolated from this plant for the first time. Compound 7 was the most active, with MIC values ranging from 1 to 2 μg/ml and its antioxidant activity (IC50 = 0.71 μg/ml) was higher than that of the reference drug (IC50 = 0.96 μg/ml). Conclusion These findings demonstrate that Bryophyllum pinnatum and some of its isolated compounds have interesting antimicrobial and antioxidant properties, and therefore confirming the traditional use of B. pinnatum in the treatment of infectious and free radical damages.</p

Antibacterial and antioxidant activities of extracts and some flavonoids from the leaves of Clerodendrum buchholzii Gurke (Verbenaceae)

Morbidity and mortality due to diarrhoea continues to be a major problem in many developing countries. The most common microorganisms responsible for diarrhoeal diseases are Vibrio cholerae, Escherichia coli and Shigella spp. The present study aims to evaluate the antibacterial and antioxidant activities of extracts and compounds from the leaves of Clerodendrum buchholzii, a plant traditionally used in the African pharmacopeia for the treatment of furunculosis, echymosis and gastritis. The dried leaves were macerated in methanol (MeOH) to afford the crude extract that was extracted with ethyl acetate (EtOAc) and n-butanol (n-BuOH) to obtain EtOAc and n-BuOH extracts, respectively. The column chromatography of EtOAc and n-BuOH extracts followed by purification of different fractions led to the isolation of four known flavonoids [acacetin 7-O-β-D-glucoside (1), kaempferol 7-O-β-D-glucoside (2), acacetin (3) and apigenin (4)]. Structures of isolated compounds were assigned on the basis of spectroscopic analysis, and by comparison of our data with those of the literature. The antioxidant activity was evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and gallic acid equivalent antioxidant capacity (GEAC) assays. The antibacterial activity was assessed using broth microdilution method by performing minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) against the strains of Gram-positive bacterium, Staphylococcus aureus (a major cause of community and hospital-associated infection), and Gram-negative multi-drug resistant bacteria, Vibrio cholerae (causative agent of cholera) and Shigella flexneri (causative agent of shigellosis). All of the extracts showed different degrees of antioxidant and antibacterial activities. Apigenin (4) obtained from EtOAc extract displayed the largest antibacterial and antioxidant properties which were in some cases equal or higher than those of reference drugs. Our results showed that C. buchholzii has potentials as a natural source of anti-diarrhoeal and free radical scavenging products, and could be given further investigations.Keywords: Clerodendrum buchhlzii, Verbenaceae, Flavonoids, Antibacterial, Antioxidan

Antimicrobial activities of saponins from Melanthera elliptica and their synergistic effects with antibiotics against pathogenic phenotypes

Abstract Background Resistance of bacteria and fungi to antibiotics is one of the biggest problems that faces public health. The present work was designated to evaluate the antimicrobial activities of saponins from Melanthera elliptica and their synergistic effects with standard antibiotics against pathogenic phenotypes. The plant extract was prepared by maceration in methanol. The methanol extract was partitioned into ethyl acetate and n-butanol extracts. Column chromatography of the n-butanol extract followed by purification of different fractions led to the isolation of four saponins. Their structures were elucidated on the basis of spectra analysis, and by comparison with those from the literature. The antimicrobial activities of the extracts/compounds alone and their combinations with tetracycline and fluconazole were evaluated using the broth microdilution method through the determination of minimum inhibitory concentration (MIC) and minimum microbicidal concentration. Results Four compounds: 3-O-β-d-glucuronopyranosyl-oleanolic acid (1), 3-O-β-d-glucuronopyranosyloleanolic acid 28-O-β-d-glucopyranosyl ester (2), 3-O-β-d-glucopyranosyl(1 → 2)-β-d-glucuronopyranosyl oleanolic acid (3) and 3-O-β-d-glucopyranosyl(1 → 2)-β-d-glucuronopyranosyl oleanolic acid 28-O-β-d-glucopyranosyl ester (4) were isolated. Compounds 1, 2 and 3 showed the largest antibacterial activities (MIC = 8–128 μg/mL) whereas compound 4 displayed the highest antifungal activities (MIC = 8–16 μg/mL). The antibacterial activities of compounds 1 and 2 (MIC = 16–32 μg/mL) against multi-drug-resistant Escherichia coli S2 (1) and Shigella flexneri SDINT are equal to those of vancomycin (MIC = 16–32 μg/mL) used as reference antibiotic. Conclusions The present study showed significant antimicrobial activity of compounds 1, 2, 3 and 4 against the tested microorganisms. The saponins act in synergy with the tested standard antibiotics. This synergy could lead to new options for the treatment of infectious diseases and emerging drug resistance

Antimicrobial activities of flavonoid glycosides from Graptophyllum grandulosum and their mechanism of antibacterial action

Abstract Background The search for new antimicrobials should take into account drug resistance phenomenon. Medicinal plants are known as sources of potent antimicrobial compounds including flavonoids. The objective of this investigation was to evaluate the antimicrobial activities of flavonoid glycosides from Graptophyllum grandulosum, as well as to determine their mechanism of antibacterial action using lysis, leakage and osmotic stress assays. Methods The plant extracts were prepared by maceration in organic solvents. Column chromatography of the n-butanol extract followed by purification of different fractions led to the isolation of five flavonoid glycosides. The antimicrobial activities of extracts/compounds were evaluated using the broth microdilution method. The bacteriolytic activity was evaluated using the time-kill kinetic method. The effect of extracts on the red blood cells and bacterial cell membrane was determined by spectrophotometric methods. Results Chrysoeriol-7-O-β-D-xyloside (1), luteolin-7-O-β-D-apiofuranosyl-(1 → 2)-β-D-xylopyranoside (2), chrysoeriol-7-O-β-D-apiofuranosyl-(1 → 2)-β-D-xylopyranoside (3), chrysoeriol-7-O-α-L-rhamnopyranosyl-(1 → 6)-β-D-(4"-hydrogeno sulfate) glucopyranoside (4) and isorhamnetin-3-O-α-L-rhamnopyranosyl-(1 → 6)-β-D-glucopyranoside (5) were isolated from G. grandulosum and showed different degrees of antimicrobial activities. Their antibacterial activities against multi-drug-resistant Vibrio cholerae strains were in some cases equal to, or higher than those of ciprofloxacin used as reference antibiotic. The antibacterial activities of flavonoid glycosides and chloramphenicol increased under osmotic stress (5% NaCl) whereas that of vancomycin decreased under this condition. V. cholerae suspension treated with flavonoid glycosides, showed a significant increase in the optical density at 260 nm, suggesting that nucleic acids were lost through a damaged cytoplasmic membrane. A decrease in the optical density of V. cholerae NB2 suspension treated with the isolated compounds was observed, indicating the lysis of bacterial cells. The tested samples were non-toxic to normal cells highlighting their good selectivity index. Conclusions The results of the present study indicate that the purified flavonoids from G. glandulosum possess antimicrobial activities. Their mode of antibacterial activity is due to cell lysis and disruption of the cytoplasmic membrane upon membrane permeability

Antimicrobial triterpenes from the stem bark of crossopteryx febrifuga

Chouna JR, Tamokou J-de-D, Nkeng-Efouet-Alango P, Lenta BN, Sewald N. Antimicrobial triterpenes from the stem bark of crossopteryx febrifuga. Zeitschrift für Naturforschung C. 2015;70(7-8):169-173.Phytochemical investigation of the stem bark extract of Crossopteryx febrifuga resulted in the isolation of epimeric mixtures of 3 beta-urs-12,20(30)-diene-27,28-dioic acid and 18-epi-3 beta-urs-12,20(30)-diene-27,28-dioic acid (1), as well as: 3 beta-D-glucopyranosylurs-12,20(30)-diene-27,28-dioic acid and 18-epi-3 beta-D-glucopyranosylurs-12,20(30)-diene- 27,28-dioic acid (2), together with some known compounds such as the monoglyceride of palmitic acid, as well as beta-sitosterol and its glucoside. The structures of the isolated compounds were determined by application of spectroscopic methods. The MeOH extract and compounds 1 and 2 were examined for antimicrobial activity in in vitro assays against bacteria (Enterobacter aerogenes ATCC13048, Escherichia coli ATCC8739, Klebsiella pneumoniae ATCC11296, Staphylococcus aureus) and fungi (Candida parapsilosis, Candida albicans ATCC 9002 and Cryptococcus neoformans IP 90526). The tested samples showed selective activities. The antibacterial and antifungal activities of compound 2 (MIC = 8-64 mu g/mL) were in some cases equal to or even higher than those of the respective reference drugs chloramphenicol (MIC = 16-64 mu g/mL) and nystatin (MIC = 128-256 mu g/mL)

Antibacterial secotirucallane triterpenes from the stem bark of Pseudocedrela kotschyi

Mambou CS, Nono RN, Chouna JR, Tamokou J-de-D, Nkeng-Efouet-Alango P, Sewald N. Antibacterial secotirucallane triterpenes from the stem bark of Pseudocedrela kotschyi. Zeitschrift für Naturforschung C. 2018;73(5-6):241-246.The antibacterial-guided investigation of the stem bark extract of Pseudocedrela kotschyi led to the isolation of a new secotirucallane triterpene derivative: 4-hydroxy-3,4-secotirucalla-7,24-dien-3,21-dioic acid (1), together with the known one: 3,4-secotirucalla-4(28),7,24-trien-3,21-dioic acid (2) and 3-methyl ester 3,4-secotirucalla-4(28),7,24-trien-3,21-dioic (3). The structures of the isolated compounds were elucidated on the basis of extensive 1D- and 2D-NMR spectroscopy. Extracts, fractions and compounds (1-3) were tested in vitro for antibacterial activity against two Gram positive bacteria (Bacillus subtilis and Staphylococcus aureus ATCC 25923), and two Gram negative bacteria (Escherichia coli S2(1) and Pseudomonas aeruginosa). The MeOH extract and the Hex/CH2Cl2 (70:30) fraction showed significant levels of activity (MIC = 64-256 mu g/mL) compared with the two reference drugs [ciprofloxacin: MIC (0.5-1 mu g/mL) and amoxicillin: MIC (1-128 mu g/mL)]. Moreover, the compound 2 isolated from this Hex/CH2Cl2 (70:30) fraction had the greatest potential value against S. aureus, E. coli and P. aeruginosa, with minimum inhibitory concentrations (MIC) ranging from 4-16 mu g/mL