In Vivo Diuretic Activity and Anti-Hypertensive Potential of Hibiscus sabdariffa Extract by Inhibition of Angiotensin-Converting Enzyme and Hypertension Precursor Enzymes.

Aqueous extracts of calyx from Hibiscus sabdariffa (HS) (roselle) are highly appreciated for their nutritional and therapeutic effects, especially as anti-hypertensive substances. This study aimed to evaluate their anti-hypertensive potential through an in vitro inhibition assay of angiotensin-converting enzyme (ACE) and hypertension precursor enzymes and to assess the in vivo diuretic activity of HS. Results showed that HS extract inhibited enzymes belonging to several classes, such as α-amylase, trypsin, chymotrypsin, xanthine oxidase, lipoxygenase, and angiotensin-converting enzyme. In particular, enzymatic kinetics of ACE indicated a competitive inhibition fashion of HS extract. Furthermore, the extracts showed remarkable diuretic and natriuretic effects at doses of 50 mg/kg/bw, 100 mg/kg/b.w, and 200 mg/kg.b.w. These activities can be explained by the high content of phenolic compounds and essential amino acids. Roselle could be a potential source of nutraceuticals and anti-hypertensive bioactive compounds.

Correction: Hibiscus sabdariffa: Genetic variability, seasonality and their impact on nutritional and antioxidant properties.

[This corrects the article DOI: 10.1371/journal.pone.0261924.].

Modelling and optimisation of ultrasound-assisted extraction of roselle phenolic compounds using the surface response method.

Extracts from Hibiscus sabdariffa L. (roselle) have been used traditionally as a food, in herbal medicine, in hot and cold beverages, as flavouring or coloring agent in the food industry. In vitro and in vivo studies and trials provide evidence, but roselle is poorly characterised phytochemically due to the extraction processes. The optimization of the extraction of phenolic compounds and their antioxidant activities is still a hot topic. In this study, the effect of solute/solvent ratio (33, 40 and 50 mg/mL), extraction temperature (40, 50 and 60 °C) and extraction time (30, 60 and 90 min) was evaluated through the content of phenolic compounds and antioxidant activity. A response surface methodology through a Box-Behnken design was applied and model fit, regression equations, analysis of variance and 3D response curve were developed. The results showed that TPC, TFC, DPPH and FRAP were significantly influenced by temperature, extraction time and solvent/solute ratio. Thus, TPC, TFC, DPPH and FRAP varied from 5.25 to 10.58 g GAE/100 g DW; 0.28 to 0.81 g QE/100 g DW; 0.24 to 0.70 mg/mL; 2.4 to 6.55 g AAE/100 g DW respectively. The optimal experimental condition (41.81 mg/mL; 52.35 °C and 57.77 min) showed a significant positive effect compared to conventional methods. The experimental values at this extraction condition show that this optimization model is technologically, financially and energetically viable as it requires a reasonable concentration, time and temperature.

Correlating the morphology of Anacardium occidentale L. fruits from 30 orchards with their physicochemical and nutritional properties.

Cashew (Anacardium occidentale L.) is a cross-pollinating plant whose fruit consists of two parts, the nut, and the apple. This study aimed to carry out agro-morphological characteristics of cashew fruits to establish relationships with their physicochemical and nutritional properties. Thirty (30) cashew accessions fruits were sampled in different regions of Burkina Faso. The length, width, thickness, weight, yield, kernel output ratio (KOR), proximate composition, specific minerals, phenolic compounds, and anti-nutritional factors were assessed. Evaluations were made using standard methods. The results showed significant variations in agro-morphological, physicochemical and nutritional traits depending on the accessions and the organ. Also, the ratio of apple mass versus nut one was about 12.24 ± 1.24. Kernels are an important source of proteins, fat, total phenolic compounds, and flavonoids, with average contents of 22.84 ± 1.25 g/100 g, 51.65 ± 2.54 g/100 g, 9.78 ± 2.15 mg GAE/g, and 6.24 ± 12.15 mg QE/g, respectively. As for the apples, they contained substantial quantities of Potassium, Phosphorus, Chlorine, and Magnesium with contents of 611.24 ± 14.5 mg/100 g, 418.24 ± 16.47 mg/100 g, 332.24 ± 10.54 mg/100 g, and 224.95 ± 13.15 mg/100 g, respectively. Statistical analyses showed that mineral and phytate contents were positively correlated to cashew apples while phenolic compounds and tannins were strongly correlated with walnuts. Principal component analyses showed three groups of accessions based on apples and kernels characteristics. These data showed a direct relationship between cashew physicochemical, nutritional potentials, kernels, and apples' agro-morphological characteristics. These data constitute an important basis for the identification of cashew accessions with high nutritional and economic potential.

Comparison of Proximate and Phytonutrient Compositions of Cashew Nuts and Apples from Different Geographical Areas of Burkina Faso.

The cashew plant is an allogamous plant that produces two types of fruits: the nut and the cashew apple. The present study was conducted to perform a comparison of proximate and phytonutrient compositions of cashew (Anacardium occidentale L.) nuts and apples from different geographical areas of Burkina Faso. For this purpose, 60 samples of apples and kernels were collected from the three main cashew cultivation areas. The nutritional potential of cashew nuts and apples produced was evaluated to enhance their food processing. Protein, carbohydrates, lipids, dietary fibers, ascorbic acid, tannins, anthocyanins, chlorophyll, lycopene, and ß-carotene contents were assessed. The results revealed high contents of lipids (50.42 ± 2.3 g/100 gDW), proteins (22.32 + -1.8 g/100 gDW), and starch (12.05 ± 1.27 g/100 g DW) in almonds. Apples, on the other hand, are rich in lipids, ascorbic acid (387.45 ± 17.4 mg/100 g), soluble sugars (387.45 ± 17.4 mg/100 g,), and pigments (lycopene, anthocyanin, ß-carotene, and chlorophyll). In summary, almonds may be suitable as a source of lipids and related products. Apples can be used as natural antioxidants and produce juices. All of these data are important clues for cashew by-product processing. These results obtained provide a scientific basis for their food and economical valorization of cashew fruits.

Assessing the Quality of Burkina Faso Soybeans Based on Fatty Acid Composition and Pesticide Residue Contamination.

Soybean is widely used in the food industry because of its high fatty acid and protein content. However, the increased use of pesticides to control pests during cultivation, in addition to being a public health concern, may influence the nutritional quality of soybeans. This study aimed to assess the nutritional quality of soybeans with respect to fatty acid profile and pesticide residue contamination. The levels of fatty acids and pesticides in soybean varieties G196 and G197 were determined by gas chromatography and by the QuEChERS method, respectively. The results showed a significant variation in the quantitative and qualitative fatty acid composition of the two varieties, with 18.03 g/100 g and 4 fatty acids detected for the G196 variety and 21.35 g/100 g and 7 fatty acids for the G197 variety, respectively. In addition, 12 active pesticide compounds were found, and among them, imazalil, quintozene, cyfluthrin and lindane exceeded their maximum limits. The G197 variety had a better nutritional profile compared to G196. The profile of fatty acids and the content of pesticide residues were used as important determinants for soybean utilization in human nutrition.

Toxicological profile, phytochemical analysis and anti-inflammatory properties of leaves of Vitex doniana Sweet. (Verbenaceae).

Background: Natural herbal compounds are a source and alternative for new compounds with anti-inflammatory properties. Therefore, in-depth studies should be carried out to assess their safety and efficacy in order to avoid or prevent toxicological risks of these natural plant-based substances. V. doniana is a species of food plant used for the treatment of inflammatory diseases in Burkina Faso. This study aimed to estimate the anti-inflammatory properties in vitro and in vivo of the ethyl acetate fraction of the leaves of V. doniana. Methods: To do this, acute toxicity was first evaluated on the animal model. Biological activities (carrageenan test, formalin and xylene induced oedemas) were used to assess the anti-inflammatory power. Results: Regarding the dietary toxicology of the extracts, visual and clinical signs showed that the extracts are not at the end of the 15-day (acute toxicity) and 45-day (subacute toxicity) tests. In terms of anti-inflammatory activity in vivo, it was observed that the bioactive fraction (50, 100 and 200 mg/kg.b.w) had effective neurogenic anti-inflammatory properties. All of these effects observed were all dose-dependent. Conclusion: The results of this present research have proven that V. donania extracts can be used as anti-inflammatories.

Tomato By-Products, a Source of Nutrients for the Prevention and Reduction of Malnutrition.

Malnutrition is a global phenomenon that mainly affects children under five years old, the elderly and food insecure people. It can be linked to undernourishment or overnutrition. To prevent it, a healthy and balanced diet, rich in energy and micronutrients, is necessary. The objective of this study was to evaluate the nutritional composition and contribution of tomato by-products to prevent and reduce malnutrition. Thus, standard methods were used for proximate composition and bioactive compounds. Results showed that tomato by-products are rich in macronutrients and micronutrients capable of preventing undernutrition and reducing the incidence of the effects of overnutrition. The average carbohydrate, protein and lipid contents were 15.43%, 11.71% and 5.4% (DM) in peels and for seeds the contents were 58.75%, 15.4% and 22.2%, respectively. The average energy values were 280.47 kcal/100 g and 472.8 kcal/100 g DM for peels and seeds, respectively. The main minerals found were, in decreasing order, potassium, magnesium, sodium, iron and zinc. High contents of phenolic compounds, lycopene, ß-carotene and vitamin C were also found in these by-products. They also presented important antioxidant activities. Due to their nutritional and bioactive compounds, tomato by-products may be included in functional food formulation programs to reduce the incidence of nutritional diseases.

Evaluation of the physicochemical parameters of edible oils sold in the three cities of Burkina Faso.

The edible oil needs of African countries are met by imported or locally produced ones. Therefore, consumers are generally confronted with a choice of edible oils of poorly controlled quality. However, quality control of edible oils for local consumption is of high necessity. This study aimed to assess the quality of edible oils sold and consumed in some cities in Burkina Faso. Oil samples collected in the cities of Dédougou, Koudougou, and Nouna were used for several analyses. Oil samples from palm, refined and unrefined cottonseed, and groundnut were collected. Standard methods were used to assess the physicochemical quality parameters of the oils, including the peroxide value, water and volatile matter content, acid value, traces of soap, and mineral oil contents. The parameters varied significantly depending on the oil type, but not by the locality of origin. The peroxide indices had varied from 3.24 to 39.99 mEq O2/kg oil. The acid indices varied from 0.22 mg KOH/g to 1.24 mg KOH/g. The water and volatile matter contents ranged from 0.04% to 0.88%. The test for traces of soap gave values ranging from 0 to 76 ppm. For the mineral oil test, four samples of cottonseed oil collected in Dedougou gave positive results. Compared to international reference standards, in particular the Codex Alimentarius standard, it may constitute a health risk for consumers. The poor storage, distribution, and marketing conditions of the oils could explain their poor quality. In order to provide consumers with quality oils, regular controls must be undertaken in the places where the oils are stored and/or marketed.

Hibiscus sabdariffa: Genetic variability, seasonality and their impact on nutritional and antioxidant properties.

This study consisted of the physicochemical, phytochemical and antioxidant characterisation of two varieties of Hibiscus sabdariffa, to evaluate the influence of genetic and environmental factors on these parameters leading to an objective and rigorous classification of our extracts. To this end, calyxes and seeds of the red and white phenotypes were collected in Bobo-Dioulasso, Dano and Nouna respectively in December 2019 and 2020. Principal component analysis showed that physico-chemical and biochemical parameters could potentially be used to discriminate varieties. The calyxes of the sabdariffa variety showed the best physicochemical profile (total phenolics, flavonoids, ascorbic acid), pigments (anthocyanins, chlorophyll) and antioxidant activity (free radical scavenging and SOD activity) while the seeds showed the best carbohydrate, lipid and peroxidation inhibition content. In view of these results, the red phenotype has an interesting nutritional and therapeutic potential. It could therefore be interesting candidate in the pharmaceutical and food industries.

Safety Profile, In Vitro Anti-Inflammatory Activity, and In Vivo Antiulcerogenic Potential of Root Barks from Annona senegalensis Pers. (Annonaceae).

Annona senegalensis (Annonaceae) is a tropical shrub widely distributed in Burkina Faso. This plant is traditionally used as a medicine against many pathologies including typhoid fever, gastrointestinal disorders, ulcers, and inflammatory and infectious diseases. The present study was conducted to evaluate the anti-inflammatory and antiulcer properties of Annona senegalensis root bark extracts. Therefore, toxicity tests were first performed, followed by other biological tests. For this purpose, we first undertook to evaluate the toxicity tests before considering the other biological tests in a second step. The results showed that the extracted fractions had a significant effect for the different methods used (protein denaturation inhibition activity, hyaluronidase inhibition activity, and xanthine oxidase inhibition activity). However, of the extracted fractions used, the ethyl acetate fraction was the most anti-inflammatory fraction. The antiulcer activity was evaluated using the best bioactive fraction. The antiulcer effect of the ethyl acetate fraction may be due to both the reduction of gastric acid secretion and gastric cytoprotection. The results of this study also showed that the bioactive fraction reduced ethanol-induced ulceration and pyloric ligation in a dose-dependent manner, and at the highest dose (200 mg/kg), the effect was similar to that of the reference drug. In summary, the ethyl acetate fraction was found to have the best anti-inflammatory and antiulcerogenic activities. The ethyl acetate fraction at a dose of 200 mg/kg also showed a rather interesting level of cytoprotection. The anti-inflammatory and antiulcer activities could be due to the different secondary metabolites contained in the fractions extracted from Annona senegalensis, notably flavonoids, triterpenoids, steroids, saponins, and tannins. As the mechanisms of action are still little or not understood, we will consider in the future identifying the phytoconstituents and the mechanisms of action involved in the results.