Proximate composition of traditional local sorghum beer “dolo” manufactured in Ouagadougou

Dolo is a local beer manufactured from malted sorghum grains. It is the most commonly consumed alcoholic beverage in Burkina Faso (60% of population). Thirty (30) samples of dolo were collected from local markets in Ouagadougou and analyzed with respect to their proximate compositions and pH values using biochemical standard method. The average values of pH, dry matter and insoluble matter among samples were respectively 3.50±0.07, 5.90±1.24% (w/v) and 0.85±0.32% (w/v). Alcohol content in dolo samples was on average 2.30±0.25% (v/v). The total proteins, total carbohydrates and reducing sugars were 26±14.8, 38±20.4 and 10±3.8 μg/ml, respectively. The lipids were detected as traces in all dolo samples. The energetic value of dolo was on average 21.8±1.6 Kcal/100 ml of which these parameters characterize the quality of dolo.Keywords: Sorghum bicolor, local beer, dolo, alcohol content, composition, Burkina FasoAfrican Journal of Biotechnology Vol. 12(13), pp. 1517-152

Optimization of Aqueous Extraction of Anthocyanins from Hibiscus sabdariffa L. Calyces for Food Application

Aqueous extracts of Hibiscus sabdariffa calyces are worldwide used for the production of several products such as polyphenolic-antioxidant containing beverages. However, optima conditions for extraction of polyphenolics such as anthocyanins from this plant species were unknown. For this, the influence of particle size and calyx/water ratio on the anthocyanins extraction and biochemical composition during extraction were investigated using bright red and dark red Hibiscus sabdariffa calyces.Results showed that the pH of the bright red calyces was 2.24 ± 0.01 corresponding to 12.66 ± 0.15 g/100g dry weight (DW) titratable acidity equivalent of malic acid. The pH of the dark red calyces was 2.15 ± 0.01 corresponding to 15.44 ± 0.15 g/100g DW titratable acidity equivalent malic acid. Total sugars content was 3.24±0.04 and 3.13±0.06 g/100g DW for bright red and dark red, respectively. Proteins content ranged from 4.56 ± 0.04 to 6.96 ± 0.17 g/100g DW. The level of the total phenols ranged from 3.82 ± 0.33 to 5.22 ± 0.08 g/100g DW. Average anthocyanins content was 2.61 ± 0.11 and 2.98 ± 0.02 g/100g DW for dark red and bright red calyces, respectively. Calyces were found to show an antioxidant capacity of up to 300 µmolTrolox equivalent/100g. For all calyx/water ratios, the anthocyanins content increased with extraction time till 60 min and remained almost stable thereafter.The optimization of the aqueous extraction was obtained at the ratio 1/10 (calyx/water) for the production of roselle concentrated extract, using calyces size less than 250 µm,at 30°C, for one hour percolation. Keywords: Hibiscus sabdariffa L, anthocyanins water, calyx/water ratio, particle size, optimization, extraction

Caractéristiques physicochimiques de quelques matières premières utilisées dans la formulation des aliments pour volaille au Burkina Faso

Objectifs : Connaitre la composition physicochimique des matières premières les plus utilisées dans la formulation des aliments pour volaille.Méthodologie et Résultats : Une étude prospective a permis de répertorier les matières alimentaires les plus utilisées pour l’alimentation de volaille au Burkina Faso. Les principaux constituants ont été déterminés par les méthodes AOAC. Les acides aminés et les minéraux ont été déterminés respectivement par la chromatographie et la spectrométrie à flamme. Les résultats ont montré des proportions massiques (g/100g MS) comprises entre 9,17±0,13 et 59,9±0,27 pour les protéines, 2,24±0,10 et 15,56±0,03 pour les lipides,4,16±0,04 et 73,8±0,07 pour les carbohydrates totaux, entre 6,04±0,13 et 14,53±0,07 pour la cellulose, 0,01±0,00 et 34,03±0,07 pour le calcium, 0,02±0,07 et 18,01±0,00 pour le phosphore. Les teneurs enméthionine, lysine, thréonine étaient respectivement comprises entre 0,19±0,02 et 1,49±0,03 ; 0,25±0,06 et 2,38±0,03, et 0,30±0,03 et 2,32±0,03.Conclusion et application des résultats: Il ressort de cette étude que la farine de poisson présente les teneurs les plus élevées en protéine (59,9± 0,27 g/100g), calcium (6,42± 0,04 g/100g) et phosphore (3,88± 0,06 g/100g). Le soja est le plus riche en matière grasse (17,98± 0,10 g/100g) et le maïs jaune est le plus riche en glucide (73,8± 0,07 g/100g). Ces données produites peuvent servir à l’établissement de tables de composition des matières premières locales utilisables dans l’alimentation de volaille et leur vulgarisationauprès des aviculteurs leur permettra de mieux s’orienter dans le choix des ingrédients de hautes valeurs nutritionnelles et de réduire le coût de la formulation. Objectives: To know the physicochemical composition of the raw materials mostly used in the formulation of poultry feed.Methodology and Results: A prospective study was carried out to identify the most commonly used feed materials for poultry feed in Burkina Faso. The main constituents were determined by AOAC methods. Amino acids and minerals were determined respectively by chromatography and flame spectrometry. Results showed mass proportions (g / 100g DM) between 9.17 ± 0.13 and 59.9 ± 0.27 for proteins, 2.24 ± 0.10 and 15.56 ± 0.03 for lipids, 4.16 ± 0.04 and 73.8 ± 0.07 for total carbohydrates, 6.04 ± 0.13 and 14.53 ± 0.07 for cellulose, 0.01 ± 0.00 and 34.03 ± 0.07 for calcium, 0.02 ± 0.07 and 18.01 ± 0.00 for phosphorus. Content in essential amino acids such as methionine, lysine, and threonine ranged between 0.19 ± 0.02 and 1.49 ± 0.03, 0.25 ± 0.06 and 2.38 ± 0.03, and 0.30 ± 0.03 and 2.32 ± 0.03, respectively.Conclusion and application of results: It emerges from this study that fishmeal has the highest contents of protein (59.9 ± 0.27 g/100g), calcium (6.42 ± 0.04 g/100g) and phosphorus (3.88 ± 0.06 g/100g). Soy is the richest in fat (17.98 ± 0.10 g/100g) and yellow corn is the richest in carbohydrate (73.8 ± 0.07 g/100g). These data produced can be used to establish composition tables for local raw materials that can be used in poultry feed and their popularization with poultry farmers will allow them to better orient themselves in the choice of ingredients with high nutritional values and reduce the cost of formulation

Sorghum grain as human food in Africa: relevance of content of starch and amylase activities

Sorghum is a staple food grain in many semi-arid and tropic areas of the world, notably in Sub-Saharan Africa because of its good adaptation to hard environments and its good yield of production. Among important biochemical components for sorghum processing are levels of starch (amylose and amylopectin) and starch depolymerizing enzymes. Current research focus on identifying varieties meeting specific agricultural and food requirements from the great biodiversity of sorghums to insure food security. Results show that some sorghums are rich sources of micronutrients (minerals and vitamins) and macronutrients (carbohydrates, proteins and fat). Sorghum has a resistant starch, which makes it interesting for obese and diabetic people. In addition, sorghum may be an alternative food for people who are allergic to gluten. Malts of some sorghum varieties display a-amylase and ß-amylase activities comparable to those of barley, making them useful for various agro-industrial foods. The feature of sorghum as a food in developing as well as in developed countries is discussed. A particular emphasis is made on the impact of starch and starch degrading enzymes in the use of sorghum for some African foods, e.g. “tô”, thin porridges for infants, granulated foods “couscous”, local beer “dolo”, as well agro-industrial foods such as lager beer and bread.Keywords: sorghum, a-amylase, b-amylase, starch, infant porridge, beer, couscous, dolo, tô, brea

Comparison of phenolic compounds and antioxidant capacities of traditional sorghum beers with other alcoholic beverages

Thirty samples of sorghum beers “dolo” were selected from traditionally fermented household manufacturers from Burkina Faso. Dolo samples were screened for their total phenolic content, proanthocyanidins and putative antioxidant capacities, and were compared with industrial beers and wines. Total phenols were measured using the Folin-Ciocalteu method. Proanthocyanidins content were determined by the method of HCl-butanol hydrolysis. Antioxidant activities were evaluated both with 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and by the trolox equivalent antioxidant capacity (TEAC) using 2,2’-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid radical) (ABTS•+). The average contents of total phenols and proanthocyanidins were 506 μg GAE/ml of dolo and 45 μg APE/ml of dolo, respectively. An average antioxidant capacity was found in 148 μmol of TEAC per litre of dolo or 2.2 μmol of TEAC per gram of dolo. Proanthocyanidins in dolo represent on average, 10% of total phenolic content. Results also showed that the red wines from different brands had higher levels of phenolic content and antioxidant capacities than dolo. Nevertheless, dolo displays higher levels of total phenolic content than lager beers and white wines. Sorghum grains as well as their derived food-products such as local beers are good sources of bioactive compounds comparable to other industrial alcoholic beverages.Keywords: Sorghum bicolor, dolo, beer, total phenols, proanthocyanidins, antioxidant capacit

Phytochemistry and Agro-Industrial Potential of Native Oilseeds from West Africa: African Grape (Lannea microcarpa), Marula (Sclerocarya birrea), and Butter Tree (Pentadesma butyracea)

Ethnobotanical investigations on local oilseed species in Burkina Faso revealed that oils from tree oilseeds are frequently used for food, cosmetics and traditional medicine by local people. To test the bio-preservative capacity, the effect of the oilseed extracts on the stabilization of Shea butter was evaluated. Levels of bioactive phyto-components were evaluated through several methods. Some aspects of the quality of oilcakes were evaluated based on their inhibitory capacity on the endogenous digestive enzymes of cattle. For fat stabilizing quality, the extract from Lannea microcarpa Engl. & K. Krause has showed the largest increase (91.47%) in the Rancimat induction time (TIR) of Shea butter. Using DPPH and FRAP methods for prevention or scavenging of free radicals, the results evidenced the highest activity with extracts of L. microcarpa. With respect to the feed quality of the oilcakes, the IC50 obtained with α-amylase and trypsin have showed that the ethanolic extracts of Pentadesma butyracea Sabine (1824) is less toxic for cattle. These results suggest that phenolic compounds extracted from these native oilseeds, especially those of Lannea microcarpa, can be used as biological antioxidants for bio-preservation of edible fats. In addition, the by-products of the oil-extraction can be valorized as nontoxic and protein-rich oilcakes for livestock feed

Biochemical characterization of Burkina red radish (Raphanus sativus) peroxidase

Objectives: Peroxidases (POX), isoenzymes were purified to homogeneity from bulbs of Raphanus sativus (Radish) grown in Burkina Faso and characterized for use as an alternative source of POX for biotechnological applications.Methodology and Results: The enzymes were purified using cation exchange, anion-exchange and hydrophobic interaction chromatography. Two isoperoxidases, cationic POX1 and anionic POX2, were isolated and purified 18.5 and 27.2 fold, respectively. Purified enzymes were found to be monomeric proteins with molecular masses of 70 kDa and 47 kDa for POX1 and POX2, respectively, as determined by SDS-PAGE. The effect of pH and temperature was done using guaicol as a substrate. The optimal pH of the both purified POX was 5.6 and 80 % of its activity was retained at pH values between 4.0–8.0 after incubation for 2 h, but POX2 appeared to be highly stable than POX1. POX1 and POX2 had optimum temperatures of activity at 35° and 40°C, respectively. Activities of these isoenzymes were determined using different phenolic substrates in the presence and absence of ionic effectors. The results show that both POX activities were activated by bivalent cations such as Mg2+ and Ca2+ but were inhibited by K+, Na+, Zn2+, EDTA and reducing compounds. While Ba2+ is an activator for POX2, it had no effect on POX1. They oxidize all the phenolic compounds used. The greatest rate was obtained with ABTS and guaiacol, for POX1 and POX2, respectively.Conclusions and application of findings: POXs oxidize a wide range of phenolic substrates and have high stability at a wide range of pH. These properties make these enzymes potential biotechnological tools. They could be use in industrial applications to produce food dyes, phenolic resins from natural phenolic compounds or in the construction of biosensors and kits for analyses and diagnostics. They could play also an important role in the oxidation of phenolic compounds in polluted water. This is interesting because it could be useful in finding solutions to the thorny problem of recalcitrant phenolic compounds that resist to conventional methods for bioremediation.Keywords: peroxidase, purification, characterization, Raphanus sativus, phenolic compoun

PHYTOCONSTITUENTS ANALYSIS, ANTIOXIDANT CAPACITY AND ANTIMICROBIAL PROPERTIES OF EXTRACTS FROM LAGGERA AURITA L. (ASTERACEAE)

Objective: This research was designed to evaluate the polyphenolic content, antibacterial potency and antioxidant activity of extract and fractions from Laggera aurita L. (Asteraceae), a medicinal herbaceous from Burkina Faso. Methods: Folin ciocalteu and AlCl3 methods respectively were used for polyphenol contents. The antioxidant activities of the samples were evaluated by various in vitro assays like ferrous reducing antioxidant assay (FRAP), Total reducing power, 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) scavenging and ABTS radical cation decolorization assays. In vitro antibacterial capacity of bioactive fractions were investigated by agar disc diffusion, micro-well dilution (MIC), Minimum Bactericidal Concentration (MBC) assay and at least the effect of the best bioactive fraction (EAF) from Laggera aurita L. (Asteraceae) and in combination with gentamycin against food bacterial strains multi-resistants was evaluated. Results: Estimation of Total phenolic and flavonoids contents revealed that EAF and DCMF have the highest phenolic and flavonoid contents 62.12±0.68mgGAE and 10.56±0.29mgQE respectively. These results indicated that most of the bioactive fractions from Laggera aurita L. were able to inhibit Gram-positive bacteria as compared to Gram-negative bacteria. Among the samples tested for antioxidant activities, EAE and DCMF have the highest activities compared to other fractions. Conclusion: These findings suggested that Laggera aurita L. is not only an important source for antibacterial component, but also a potential source of antioxidants. So, these results may be useful in explaining the medicinal applications of Laggera aurita L