Effects of incorporation levels of Pueraria phaseoloides leaf flour on carcass characteristics and chemical composition of meat from local rabbit (Oryctolagus cuniculus) in South-East Gabon

The objective of this study was to contribute in improving knowledge on rabbit feeding in Gabon. This work was conducted with the aim of studying carcass characteristics and chemical composition of meat from rabbit induced by feeds containing P. phaseoloides. To that effect, 20 young female rabbits from local breed, weighing averagely 611 ± 33.20 g and aged about 6 weeks were randomly distributed in 4 groups of 5 animals each. The groups R0, R15, R20 and R25 were fed rations containing respectively 0%, 15%, 20% and 25% of P. phaseoloides. At the end of the trial, animals were slaughtered then eviscerated in order to evaluate carcass characteristics. Muscles were taken, ground and mixed for chemical analysis. No matter the ration, carcass characteristics showed no significant difference (p > 0.05). Highest protein contents in meat were recorded in animals from R15 (23.90% DM) and R20 (22.46% DM). The lowest fat content (5.41% DM) was that of animals from R25, followed by that from R20 (6.67% DM). Based on these results obtained, the ration containing 20% Pueraria phaseolides (R20) could be recommended

Hyper-Uricemia and Gouty Access in the Adult Population of the Southeast of Gabon: Biochemical Aspects

Gout is caused by a chronic hyperuricemia whose complications are not currently well evaluated in Africa. The aim of this study was to determine the prevalence and risk factors of hyperuricemia and gout in 85 patients recruited. A total of 26 cases of hyperuricemia, i.e., 30.6% of the study population, with 12 cases of gout and seven cases of gouty access. In this population, hyperuricemia was proportional to age (p-value < 10−4, OR = 2.6), but it was more prevalent in men, 23.5% versus 7.1% for women (p-value = 0.0047). In addition, none of these women showed signs of a gouty affection. Consumption of alcohol (OR = 13) and nucleoprotein-rich foods, obesity (BMI 30 kg/m2; OR = 6), family history of gout (OR = 6.8), as well as diseases such as high blood pressure (associated with taking diuretics; OR = 1.7), renal insufficiency (OR = 4.4) and diabetes (p < 0.049) were the main factors of the diseases associated with gout and hyperuricemia in this population. The biochemical role of these factors may increase and/or decrease the processes of synthesis and/or elimination of uric acid by acting on metabolites involved in the regulation of urate production

Cytotoxicity and Identification of Antibacterial Compounds from Baillonella toxisperma Bark Using a LC-MS/MS and Molecular Networking Approach

International audienceBaillonella toxisperma is a medicinal plant used in northern Gabon to treat microbial diseases. It is a plant well-known by local populations, but very few studies have focused on the molecules responsible for the antibacterial activities of B. toxisperma. This study proposes a dereplication strategy based on molecular networking generated from HPLC-ESI-Q/TOF data, allowing investigation of the molecules responsible for the antibacterial activity of B. toxisperma. From this strategy, eighteen compounds were putatively identified. All of these compounds belonged mainly to five families of natural compounds, including phenylpropanolamines, stilbenes, flavonoids, lignans and phenolic glycosides. The chemical study carried out from the bark of B. toxisperma allowed us to identify, for the first time, compounds such as resveratrol and derivatives, epicatechin, epigallocatechin and epigallocatechin gallate. In addition, antibacterial activity (diffusion method and microdilution) and cytotoxicity (Cell Counting Kit-8 (CCK-8 Assay)) in vitro were evaluated. The crude ethanolic extract, as well as the fractions of B. toxisperma, showed significant antibacterial activity. However, the ethanolic fractions F2 and F4 presented high antibacterial activity compared to the crude extract. Cytotoxicity studies on colon-cancer cells (Caco-2) and human keratinocyte cells (HaCaT) showed moderate cytotoxicity in both cell types. This study clearly shows the therapeutic potential of the ethanolic extract of the bark of B. toxisperma and provides information on the phytochemical composition and bioactive compounds of the plant

Chemical composition, antioxidant and antimicrobial activities of stem barks of Englerina gabonensis Engler and Sterculia tragacantha Lindl from Gabon

Aim of this work was to evaluate the phytochemical constituents, antioxidant and antimicrobial potential of water-acetone, water-ethanol and water extracts of Englerina gabonensis and Sterculia tragacantha.Presence of phenols was evaluated to estimate the effects of plants on microbial diseases. Water-acetone, water-ethanol and water extracts were examined for antioxidant activities. All plant extracts were tested against six reference strains, eleven clinical isolates and two fungal strains.Phenolic content were highest in the water-acetone and water-ethanol extracts from Englerinagabonensis in comparison with Sterculia tragacantha.The AAI (Antioxidant Activity Index)of water-acetone and water-ethanol extracts of Englerina gabunensis are superiors with 2. Plant extracts of Sterculia tragacantha show weak antioxidant activity (AAI < 0.5).The aqueous extract of Englerina gabonensis has a bactericidal effect on Salmonella Spp. Water-ethanol extract is bactericidal on Bacillus cereus LMG 13569 BHI, Salmonella Sppand Neisseria meningitides. Water-acetone extract presents a bactericidal activity on Enterococcus faecalis103907 CIP, Escherichi coli, Staphylococcus aureus, Acinetobacter baumanniiand Neisseria meningitides.Our results suggest that Englerina gabonensis extracts contain greater antioxidant and antimicrobial properties than Sterculia tragacantha extracts

Antimicrobial Plants Used by Fang Populations and Phytochemical Profiling of Erismadelphus exsul

International audienceGabon has a rich flora, many species of which are used in traditional medicine. However, little research has been carried out on this wealth. An ethnopharmacological survey in the Fang language was carried out among traditional practitioners to collect antimicrobial medicinal plants. Phytochemical profiling of ethanolic and methanolic extracts from Erismadelphus exsul Mildbr leaves was carried out using HPLC-ESI-Q/TOF and a molecular network approach. Antibacterial activity was assessed with disk diffusion and microdilution methods, antioxidant activity via DPPH and FRAP methods, and in vitro cell viability via Cell Counting Kit-8. A total of 21 medicinal plants were collected, grouped into 10 families, of which the Fabaceae is the most represented. Erismadelphus exsul was chosen for chemical and biological studies due to its citation frequency (RCF = 0.59) and the absence of previous phytochemical studies. These studies revealed 4 major families of natural compounds and annotated 19 compounds for the first time. The crude leaf extract showed significant antioxidant and antibacterial activity. Cytotoxicity studies showed that the leaves were not cytotoxic, unlike the bark. This study underlines the importance of preserving the ancestral knowledge of the Fang populations, while showing promising results for Erismadelphus exsul

Phytochemical studies, antiangiogenic, anti-inflammatory and antioxidant activities of Scyphocephalium ochocoa Warb. (Myristicaceae), medicinal plant from Gabon

Abstract Background The search for new anti-cancer molecules is one of the main concerns of oncology researchers. Scyphocephalium ochocoa is a plant of Myristicaceae family, used in traditional medicine against inflammatory diseases and several types of cancer. It is well established that free radicals, chronic inflammation and angiogenesis play an important role in initiation, tumor progression and metastasis formation. The aim of this study was to carry out a phytochemical screening, to determine the phenolic compounds content, to investigate the antiangiogenic, anti-inflammatory and antioxidant activities of water, water-ethanol and ethanol extracts of S. ochocoa. Methods Phytochemical screening and determination of phenolic compounds content were performed using standard methods. Antiangiogenic activity was assessed using chick chorioallantoic membrane (CAM) model and Drabkin test. Anti-inflammatory activity was estimated by protein denaturation and erythrocyte membrane stabilization method. Finally the antioxidant activity was appreciated by DPPH radical inhibition and phosphomolybdenum assay. Results The results of phytochemical studies show that extracts of bark of S. ochocoa are rich in polyphenols, tannins, flavonoids, proantocyanidins, saponosides, flavonols, flavanonols, sterol and triterpenes. The water extract showed good antiangiogenic activity (IC50 = 1.153 μg/mL). Strong anti-inflammatory activity was observed with all extracts, IC50 ranging from 34.775 ± 2.543 μg/mL to 74.577 ± 3.456 μg/mL for protein denaturation inhibition test and IC50 values ranging from 36.793 ± 0.529 μg/mL at 48.912 ± 0.957 μg/mL for antihemolytic activity. In addition, all extracts showed good antioxidant activity marked by a strong inhibition of the DPPH radical (IC50 ranging from 4.969 ± 0.263 μg/mL to 16.188 ± 0.336 μg/mL and AAI ranging from 3.090 ± 0.065 to 10.080 ± 0.517) and by greater total antioxidant capacity (with contents ranging from 37.654 ± 0.995 to 131.302 ± 1.102 VtCE (mg)/g dry extract). Conclusion Ultimately, these results could justify the use of S. ochocoa extracts in traditional medicine in the treatment of diseases related to angiogenesis and cancer, inflammatory diseases and diseases due to oxidative stress. A phyto-product with such a pharmacological profile could be a good candidate for the development of anticancer

Correction to: Phytochemical studies, antiangiogenic, antiinflammatory and antioxidant activities of Scyphocephalium ochocoa Warb. (Myristicaceae), medicinal plant from Gabon

Following the publication of this article [1], the authors noticed that Figs. 1, 2 and 3 were in the incorrect order and thus had incorrect captions. The images that were incorrectly published as Figs. 1, 2 and 3 should have been published as Figs. 2, 3 and 1 respectively

Structure elucidation of a new lanostane triterpene from Gabonese Ganoderma orbiforme fruiting bodies

International audienceThe structure and complete nuclear magnetic resonance (NMR) assignments of orbifomitellic acid, a novel lanostane triterpene isolated from the fruiting bodies of a Gabonese Ganoderma orbiforme (Polyporaceae), are reported. Within the vast catalogue of lanostanes documented from Ganoderma spp., orbifomitellic acid is the first disclosing a -COOH group at C-4

Combined LC-MS/MS and Molecular Networking Approach Reveals Antioxidant and Antimicrobial Compounds from Erismadelphus Exsul Bark.

International audienceErismadelphus exsul Mildbr bark is widely used in Gabonese folk medicine. However, little is known about the active compounds associated with its biological activities. In the present study, phytochemical profiling of the ethanolic extract of Erismadelphus exsul was performed using a de-replication strategy by coupling HPLC-ESI-Q/TOF with a molecular network approach. Eight families of natural compounds were putatively identified, including cyclopeptide alkaloids, esterified amino acids, isoflavonoid- and flavonoid-type polyphenols, glycerophospholipids, steroids and their derivatives, and quinoline alkaloids. All these compounds were identified for the first time in this plant. The use of molecular networking obtained a detailed phytochemical overview of this species. Furthermore, antioxidant (2,2-diphenyl-1-picryl-hydrazylhydrate (DPPH) and ferric reducing capacity (FRAP)) and in vitro antimicrobial activities were assessed. The crude extract, as well as fractions obtained from Erismadelphus exsul, showed a better reactivity to FRAP than DPPH. The fractions were two to four times more antioxidant than ascorbic acid while reacting to FRAP, and there was two to nine times less antioxidant than this reference while reacting to DPPH. In addition, several fractions and the crude extract exhibited a significant anti-oomycete activity towards the Solanaceae phytopathogen Phytophthora infestans in vitro, and, at a lower extent, the antifungal activity against the wheat pathogen Zymoseptoria tritici had growth inhibition rates ranging from 0 to 100%, depending on the tested concentration. This study provides new insights into the phytochemical characterization and the bioactivities of ethanolic extract from Erismadelphus exsul bark