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Tomato is a vegetable/fruit highly consumed all other the world. This study was to assess the effect of some postharvest processing such as thermal treatment, microwave, ultrasound and ultrasound combined with heat treatment on some physicochemical characteristics as well as nutrients content of tomato pulp during storage at room temperature. Results showed that the pulp samples submitted to ultrasonic and microwave treatments gave an increase in water content (95.65 to 96.75%) and total acidity (0.70 to 1.16% citric acid equivalent) and a decrease in pH (4.02 to 3.59) and brix degree (4.93 to 4.02% Brix) during the first 15 days of storage. Ultrasound treatment associated with heat treatment did not affect the physicochemical characteristics of tomato pulp and the β-carotene, but slightly reduced the total phenolic content during the first 15 days of storage (723.98 to 659.66 mg GAE/100 g DM). A significant increase in the total phenolic content (647.33 to 832.78 mg GAE/100 g DM) and β-carotene (10.77 to 12.90 mg GAE/100 g DM) was observed during storage of pulp samples treated with ultrasound and microwaves. This study showed that the ultrasound treatment associated with heat treatment can be recommended to processors for nutrients preservation during storage. Key words: Tomato pulp, s-carotene, total phenolic, physicochemical characteristics, ultrasound, heat.

Biomethane potential production from cashew nut hulls, an agricultural waste, was carried out using old and fresh hulls as substrates. Samples were taken from old hulls (around 8 years old) and fresh hulls produced in cashew scale transformation units at Bobo Dioulasso/Burkina Faso. Physicochemical parameters showed that cashew hulls can be a good candidate for anaerobic digestion. But high acidity, total phenols and lignin tenor could be a constraint for anaerobic bacteria. Theoretical biochemical methane potential showed high value of 666.937 CH4 L. (Kg VS)-1 and 526.206 CH4 L. (Kg VS)-1 for crushed fresh and powdered old hulls, respectively. Experimental biochemical methane potential showed significantly low potential of 1.982 CH4 L. (Kg VM)-1 and 46.840 CH4 L. (Kg VM)-1 for fresh and hold hulls, respectively. Pretreatment for optimization, chemical composition and co-digestion system must be expected for a better anaerobic digestion performance.

Essential oils are natural substances which can be used as natural conservators for foods. The present work aimed to evaluate biological properties of essential oil of Hyptis suaveolens and its effect on shelf-life of beef. The extraction was carried out by hydro-distillation. Antioxidant activity was determined by method of DPPH and FRAP. Antimicrobial activity was determined by the microdilution and agar diffusion methods. The sensitivity of eleven pathogen microbial strains was tested. The conservation test of ground meat using essential oil was carried out by monitoring the evolution of the microbial groups. Result showed that extraction yield of essential oil was 0.21% (m/v). The DPPH assay gave IC50 of 16.367 ± 0.0739 µL and was confirmed by the FRAP assay. The essential oil from H. suaveolens showed inhibitory activity on microbial strains. Biopreservation assay revealed a significant decrease of microbial charge during conservation time. Thus essential oil was successful in vitro and its activity on prolonging shelf-life of beef was found to be 7 days. The results of the present study demonstrated the possibility of essential oil from H. suaveolens to be used as natural conservator for food industry. Key words: Hyptis suaveolens, essential oil, biopreservation, biological properties, meat.

Acetic acid bacteria are known for their ability to oxidize ethanol to acetic acid. This study investigated to identify dominant strain acetic acid bacteria involving in fermented juice of mango and capable to produce Vinegar, total of 4 bacteria (CRSBAN-BVA1, CRSBAN-BVK1, CRSBAN-BVK2, CRSBAN-BVI1) bacteria strains were preselected ¶for the analyses. The strains were examined with biochemical, physiological and phenotypical methods such as Gram die, catalase and oxidase test, ethanol oxidation to acetic acid, and over to CO2 and H2O and also metabolism of carbohydrate was tested, for their affiliation to the genera of acetic acid bacteria. Subsequently, genotypic identification was conducted by sequencing the gene coding for 16S rRNA of one targeted strain and phylogenetic analysis was realized throughout 16S rRNA sequences. The results showed that one of the isolated strain (CRSBAN-BVA1) present 99. 90% of similarity in the sequence 16S rRNA region with Acetobacter tropicalis. It demonstrated that bacterial diversity in the mango vinegar is dominated by A. tropicalis. Therefore this strain is potentially useful for its utilization as a starter in vinegar production. Key words: Fermented juice, acetic acid bacteria, 16S rRNA gene sequence, Acetobacter tropicalis.

In Burkina Faso, deficiency of amino acids in protein is becoming a major healthy public problem. This study was purposed to optimize essentials amino acids in single cell protein (SCP) by supplementing different nitrogen sources during fermentation of mango waste with Candida utilis FJM12. Analytical methods were used to determine biomass yield, chemical composition and amino acids profile of SCP. The principal component analysis (PCA) method was performed to identify the nitrogen source which exhibited best rate of SCP. The maximum biomass yield (6.48±0.03 g/L) exhibited 9.65±0.36% (w/w) of ash, while using yeast extract. The proximate composition of SCP revealed 56.40±1.30, 13.25±0.11, 3.80±0.10, and 6.60±0.25% (w/w), respectively for crude protein, lipids, carbohydrates, and nucleic acid content. PCA showed a strong correlation between yeast extract and Ammonium sulphate and demonstrated their positive influence to increase the rate of SCP and essentials amino acids as compared to Food and Agriculture Organization (FAO) recommendation. These results demonstrated that C. utilis FJM12 could be suitable for essentials amino acids. Key words: Mango waste, nitrogen source, Candida utilis, single cell protein (SCP), amino acids.

Tomato (Lycopersicon esculentum Mill) is quantitatively the highest vegetable consumed in Burkina Faso. The objective of this study was to evaluate the physico-chemical, nutritional characteristics, and sanitary quality of the tomato variety Mongal F1 from different production sites. Twenty-eight (28) samples of Mongal F1 fresh tomatoes were collected from 28 producers at three different localities of Ouahigouya, Loumbila and Ouagadougou. The physico-chemical and nutritional characteristics were determined by standardized methods and the traces metallic elements by atomic absorption spectrophotometry. The results revealed a degree brix varying from 4.07° to 5.50° and a pH ranging from 3.71 to 4.08 corresponding to a total acidity of 0.39% to 0.55% citric acid equivalents. The moisture content, the ash content, the total carbohydrates content, the reducing carbohydrates content, the lipids content and the protein content were ranged from 95.09% to 96.17%, 9.25% to 10.60%, 47.00% to 53.43%, 30.03% to 41.21%, 3.04% to 7.71% and 17.09% to 25.03% respectively. The results of the trace metals showed a high accumulation of total cadmium from 0.11 to 0.22 ppm, of total lead of 1.15 to 1.27 ppm and arsenic total of 0.19 to 0.20 ppm. The results proved that environmental conditions influence the quality of the tomato Mongal F1. Detection of trace elements in the tomato fruits suggests that a better production practices are needed.

This study is a contribution to the optimization of organic fraction of municipal waste bioconversion into biomethane, by activated sludge production as inoculum for digesters. The wastewater (WW) and cow dung (CD) samples were taken from the slaughterhouse of Ouagadougou town, Burkina Faso. Different mixtures were made, enriched with mineral solution and cellulose at 5% (w/v) as: 10% CD + 90% WW (C7), 30% CD + 70% WW (C6), 50% CD + 50% WW (C5), 70% CD + 30% WW (C4), 90% CD + 10% WW (C3), 100% CD (C2) and 100% WW (C1). The pH evolution and biogas (CH4 and CO2) production were followed for 25 days. Cultures tend to acidify with increase in cow dung proportion. Biogas production was significantly higher (p < 0.05) in C5 (880.0 mL), C6 (862.0 10 mL) and C7 (772.0 mL). Mixture C5 had a highest level of CO2 production (40%). Also C7 and C6 retained in the experiment contained respectively organic matter, volatile fatty acids (VFA) and total alkalinity (TAC) as 41.06%, 47.02%, 1320 mg acetic acid/L, 3036 mg Acetic acid/L and 520 mg CaCO3/L, 1310 mg CaCO3/L. Mixture C6 was the best medium for microorganism proliferation stability with 3.5 × 105 UFC/ml of methanogens bacteria. It also possessed buffering capacity, which prevents acidification of medium during VFAs production.

The concentration of secondary metabolites can be influenced qualitatively and quantitatively by ecological factors and farming practices. The purpose of this study was to determine the impact of organic and mineral fertilization on physical characteristics and the content of chemical and biochemical compounds of the fruits of the tomato var. Mongal F1. Physical, chemical and biochemical characterizations of tomato samples were carried out from samples collected from control, organic and mineral fertilized plants, to assess the nutritional potential according to fertilization. Samples collected from the organic fertilizer had pH values of 4.21 ± 0.01 corresponding to measurable acidity of 8.47 ± 0.06g malic acid /100g Fresh Tomato (FT), dry matter of 4.18±0.02/100g FT and total ash content of 0.38±0.01/100g FT. The contents of fats, proteins are respectively 2.28 ± 0.01 and 0.70± 0.02 mg/100g FT, totals sugar value of 2.83± 0.02 mg/100g FT. For mineral fertilization, the samples had pH values of 4.16 ± 0.01 corresponding to a measurable acidity of 8.10 ± 0.12g malic acid /100g FT, values of dry matter 3.82 ± 0.02/100g FT and totals ash content of 0.37 ± 0.01. The contents of fats and proteins are respectively 0.27 ± 0.01 and 0.64 ± 0.01 mg/100g FT with totals sugar value of 2.56 ± 0.01 mg/100g FT. Result of study revealed that organic fertilization can increase the concentration of secondary metabolites production in tomato var. Mongal F1 than mineral fertilization. This increase may be probably due to the availability of various major and minor elements in organic fertilizer contrary to mineral fertilizer which has only three major elements, Nitrogen (N), Phosphorus (P) and Potassium (K). Globally fruit ripping has shown a positive effect on the accumulation of fats, proteins and total sugar.

Rice is one of the staple crops in Burkina Faso. However, the local production covers only 47% of the population demands. One of the main reasons of the poor productivity in Burkina Faso is iron toxicity which is related mainly to the activity of Iron Reducing Bacteria in the rice field’s ecosystems. In order to control the harmful effects of Iron Reducing Bacterial populations and to improve rice productivity, a pots experiment was conducted at the experimental site of the University Ouaga I Pr. Joseph KI-ZERBO. An iron toxic soil from Kou Valley (West of Burkina Faso) and two rice varieties, BOUAKE-189 and ROK-5, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were drained for 14 days (D2) and amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complexes). Control pots without drainage and fertilization (D0/NF) were prepared similarly. The kinetics of Iron Reducing Bacterial populations and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using a spectrometric method. Data obtained were analyzed in relation to drainage and fertilization mode, rice growth stage and rice yield using the Student’s t-test and XLSTAT 2014 statistical software. The experiment showed that the combined application of subsurface drainage and NPK + Urea + Ca + Mg + Zn fertilization, reduced significantly the number of IRB in the soil near rice roots for both rice varieties (p = 0.050 and p = 0.020) increased the leaf tissue tolerance to excess amounts of Fe, and rice yield.

Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at the site of the University of Ouagadougou, in pots containing an iron toxic soil from the Kou Valley (West of Burkina Faso). The experiment objective was to study the effect of mineral fertilizer on Iron Reducing Bacteria (IRB) dynamics and activity during rice cultivation, iron accumulation in rice plant and rice biomass yield under iron toxicity conditions. BOUAKE-189 and ROK-5 rice varieties, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complex). Control pots without fertilization were prepared similarly. The kinetics of IRB and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using spectrometric method. Data obtained were analyzed in relation to fertilization mode, rice growth stage and rice yield using the student’s t-test and XLSTAT 2014 statistical software. The experiment revealed that NPK + Urea and NPK + Urea + Ca + Mg + Zn fertilization, decreased significantly (p

Spirulina is called the ideal food for mankind and the World Health Organization considered it "super food" and the best food for the future because of its high nutritional value. The present study aimed to assess the storage influence on the levels of β-carotene and α-tocopherol in solar-dried spirulina. It was an analytical study to determine the levels of β-carotene and α-tocopherol in solar-dried spirulina using high performance liquid chromatography (HPLC). The mean contents of β-carotene and α-tocopherol of spirulina were 57.38 ± 9.98 and 1.72 ± 0.51 mg/100 g, respectively. After six months of storage, losses in β-carotene and in α-tocopherol were 24 and 28.49%, respectively. Drying and conditioning of spirulina remain the only means for broad commercial distribution. The nutritional losses that occurred during the storage of the spirulina suggest early consumption after harvesting and some special measures for conditioning and storage. Key words: Spirulina, α-tocopherol, β-carotene, farming, nutritional value.

This study is part of the search for solutions to the problems encountered in the manufacture and export of fish fillets. The production of fish fillets is mainly marked by a little mechanization. Thus, it is subjected to strong manipulation by the personnel, source of contamination. As a result, the search for thermotolerant coliforms, most of which are of fecal origin, makes it possible to assess the level of contamination of products and to judge the effectiveness of the hygiene measures taken by the fishnet production units. 190 preventive samples from 4 companies were studied. A survey was conducted to categorize the companies. Subsequently, the thermotolerant coliforms were counted on the violet crystal and neutral red (VRBL) bile lactose agar, inoculated in mass according to the French standard ISO 4832. It appears that of the 190 samples; 97.4% (185) of the results are satisfactory while 2.6% (5) of the results are unsatisfactory. The evaluation of the manufacturers of these nets indicated that there was a positive correlation between the number of serious defects and the unsatisfactory results. The result is that the best organized firms have the best laboratory results.

Sulfide toxicity is a common disease generally associated with iron toxicity which occurs in rice fields when the Sulfate-Reducing Bacteria (SRB) produce sulfides ions in anaerobic conditions. The high quantity of sulfides ions in the soil solution upsets the mineral element balance in the rice, affects its growth and causes crop yield losses. In Burkina Faso, many rice field soils are abandoned due to sulfides toxicity. The present study was developed to evaluate the impact of subsurface drainage on SRB dynamics and activity during rice cultivation and the incidence on rice production. Twelve concrete microplots with a clay-loam soil and a rice variety susceptible to sulfides toxicity (FKR 19) were used for the experiment. Soil in microplots was drained for 7 days (P1), 14 days (P2), and 21 days (P3), respectively. Control (T) microplots without drainage were prepared similarly. The evolution of SRB populations and the content of sulfides ions in the paddy soil and in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. Data obtained were analyzed in relation to drainage frequency, rice growth stage, and rice yield using the Student’s t-test and XLSTAT 7.5.2 statistical software. From the results obtained, the subsurface drainage did not affect significantly SRB populations (P = 0.187). However, the drainage affected significantly sulfides concentration in the soil near rice roots (P = 0.032). The concentration of sulfides (P < 0.0001) in soil near rice roots and the number of SRB (P < 0.0001) were significantly higher during the rice tillering and maturity stages. Although no significant difference was observed for rice yield among treatments (P = 0.209), the P2 subsurface drainage showed the highest yield and a low concentration of sulfides in soil near rice roots.

Severe acute malnutrition (SAM) has been associated with low polyunsaturated fatty acid (PUFA) status. However, investigations regarding PUFA status and correlates in children with moderate acute malnutrition (MAM) from low-income countries are scarce. The aim of this study was to describe whole-blood PUFA levels in children with moderate acute malnutrition (MAM) and to identify correlates of PUFAs. We conducted a cross-sectional study using baseline data from a prospective nutritional intervention trial among 1609 children with MAM aged 6–23 months in Burkina Faso,West Africa. Whole-blood PUFAs were measured by gas chromatography and expressed as percent of total whole-blood fatty acids (FA%). Potential correlates of PUFAs including infection, inflammation, hemoglobin, anthropometry (difference between children diagnosed as having MAM based on low mid-upper-arm-circumference (MUAC) only, low MUAC and weight-for-height z-score (WHZ), or low WHZ only) and diet were assessed by linear regression adjusted for age and sex. Children with MAM had low concentrations of whole-blood PUFAs, particularly n-3 PUFAs. Moreover, children diagnosed with MAM based only on low MUAC had 0.32 (95% confidence interval (CI), 0.14; 0.50) and 0.40 (95% CI, 0.16; 0.63) FA% lower arachidonic acid (AA) than those recruited based on both low WHZ as well as low MUAC and those recruited with low WHZ only, respectively. Infection and inflammation were associated with low levels of all long-chain (LC)-PUFAs, while hemoglobin was positively associated with whole-blood LC-PUFAs. While PUFA deficiency was not a general problem, overall whole-blood PUFA concentrations, especially of n-3 PUFAs, were low. Infection, inflammation, hemoglobin, anthropometry and diet were correlates of PUFAs concentrations in children with MAM. The trial is registered at http://www.isrctn.com ( ISRCTN42569496 ).

To promote the use of eco-toilets is an alternative to the lack of sanitation and high cost of artificial fertilisers in developing countries. Human urine is the fraction of excreta containing most nitrogen, phosphorus and potassium which are essential nutrients for plant growth. The major concern related to the use of the urine as fertiliser is the possible presence of enteric pathogens. The reduction in the numbers of Escherichia coli, Enterococcus faecalis, Salmonella sp., Staphylococcus aureus, Clostridium perfringens spores during urine storage was studied in diluted and undiluted urine samples. These experimental samples were stored in ambient air and at temperatures of 25, 35 and 42°C. The initial concentration of ammoniacal nitrogen reduced from 8260 to 1070 mg/L in quarter-diluted urine (1:3), while the pH values remained stable at 8.6 (± 0.2). E. faecalis survived for 35 days in the quarter-diluted urine at 25°C. Survival times of the tested bacteria were more shortened in ammonia concentrated samples, on storage at 35, 42°C. Except C. perfringens spores, E. faecalis was the least sensitive to storage conditions as compared to S. aureus and the two Gram-negative bacteria tested. Therefore, temperature and ammonia acted synergistically to remove bacteria in the stored urine. Likewise, C. perfringens spores were the most persistent bacteria, with only 1-log10 reduction within 100 days storage at ambient temperature. This study shows that a period of at least 30 days of undiluted urine storage at temperatures ≥ 25°C is sufficient to sanitize urine, considering only vegetative bacteria. Since urine from eco-toilets may contain other enteric organisms (viruses, protozoa, etc) appearing more persistent in external media, storage time must be lengthened for a satisfactory sanitation. Key words: Human urine, storage, enteric bacteria, ammonia, temperature, sanitation, fertilizer

Malaria remains a major public health problem due to the emergence and spread of Plasmodium falciparum drug resistance. There is an urgent need to investigate new sources of antimalarial drugs which are more effective against Plasmodium falciparum. One of the potential sources of antimalarial drugs is traditional medicinal plants. In this work, we studied the in vitro antiplasmodial activity of chloromethylenic, methanolic, and MeOH/H2O (1/1) crude extracts and decoction obtained from eight medicinal plants collected in Burkina Faso and of total alkaloids for five plants. Extracts were evaluated in vitro for efficacy against Plasmodium falciparum strain K1, which is resistant to chloroquine, pyrimethamine and proguanil using the fluorescence-based SYBR Green I assay. The antiproliferative activity on human-derived hepatoma cell line HepG2 and Chinese hamster ovary (CHO) cells was evaluated using the 3-[4,5-dimethylthyazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test in order to determine the selectivity index. Among the plant extracts tested for in vitro antiplasmodial activity, 16 were considered to be inactive (with IC50 > 10 μg/ml), six showed a moderate activity (5 < IC50 ≤ 10 μg/ml), and six were found to have a good in vitro activity with IC50 value ≤ 5 μg/ml. The highest antiplasmodial activity was found for extracts from: the alkaloid leaf extract and the chloromethylenic extracts of Combretum fragrans (IC50 = 3 μg/ml, IC50 = 5 μg/ml), the total alkaloids and the chloromethylenic leaf extracts of Combretum collinum (IC50 = 4 μg/ml), the MeOH/H2O leaf extract of Terminalia avicennioides (IC50 = 3.5 μg/ml), and the alkaloid leaf extract of Pavetta crassipes (IC50 = 5 μg/ml). Three other extracts showed moderate antiplasmodial activity (5 < IC50 ≤ 10 μg/ml): Terminalia avicennioides and Combretum fragrans methanolic extracts and Acacia kirkii alkaloid leaf extract (IC50 = 6.5, 9 and 10 μg/ml respectively). The Terminalia avicennioides crude MeOH/H2O (80:20 v/v) extract of the leaves was submitted to a successive liquid/liquid extraction with ethylacetate and n-butanol respectively. The extracts were investigated for in vitro antiplasmodial activity and antioxidant properties using DPPH(·), ABTS(+) and FRAP methods. The ethylacetate extract showed the best antiplasmodial activity (7 μg/ml) and the active constituent was isolated as ellagic acid by bioguided fractionation with an IC50 = 0.2 μM on Plasmodium falciparum and SI = 152. Besides, Terminalia avicennioides leaf extract and ellagic acid showed a good antioxidant activity. Our finding confirms the importance of investigating the antimalarial activity of plant species used in traditional medicine. Overall, two plants belonging to the Combretaceae family, Combretum fragrans and Combretum collinum appeared to be the best candidates and will be further investigated for their antiplasmodial properties, in order to isolate the molecules responsible for the antiplasmodial activity.

Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development, particularly in rural and periurban areas of Burkina Faso. The study aims to investigate the purifying capacity of Moringa oleifera defatted cake as compared to Moringa oleifera seed in the treatment of surface and well waters used for populations alimentation. A total of 90 water samples were collected in sterile glass bottles from 3 dams’ water reservoirs, a river, and a large diameter well, respectively. The water samples were treated in triplicate with Moringa oleifera seed and defatted cake coagulants. At different settling time and coagulant concentration, turbidity and pH were measured to determine the optimal conditions and factors influencing treatment with regard to sampling source. Nine physicochemical parameters (turbidity, pH, nitrates, nitrites, calcium, magnesium, total hardness, organic matter and sulfates), three bacterial fecal pollution indicators (Escherichia coli, fecal Coliforms and fecal Streptococcus) and parasite cysts were monitored based on laboratory standard methods. Data were analyzed using the Student’s t test and XLSTAT 7.5.2 statistical software. From the results obtained, for the same concentration of coagulant, settling time providing the lowest turbidity was significantly shorter (p Moringa oleifera cake than seed. Optimum settling time with Moringa oleifera cake was between 15 - 60 min versus 60 - 120 min, with Moringa oleifera seed. Both treatments significantly reduced minerals concentration in water excepted sulfates for which the concentration reversely increased. However, only Moringa oleifera cake treatment reduced organic matter content in all the water samples, while it increased with Moringa oleifera seed one (p % - 100% with M. oleifera cake treatment and 84% - 100% with M. oleifera seed one. Overall, for all water samples, Moringa oleifera cake treatment appeared more efficient in improving drinking water quality than the M. oleifera seed treatment.

This study aims to develop infant flours fortified with iron and vitamin A, taken from local products such as powder from dried Moringa oleifera leaves and pulps of Parkia biglobosa to improve the nutritional status of children aged 6 to 24 months. Chemical analyses show that, for 100 g of local flours destined for children, there are adequate protein levels (between 7.00 ± 0.44 and 12.69 ± 0.44 g) and fat content (between 7.52 ± 0.35 and 16.26 ± 0.84 g), but that there are low levels of -carotene and certain micronutrients Zn (0.67 ± 0.01 to 2.51 ± 0.19 mg), Fe (7.11 ± 0.90 to 12.70 ± 0.56 mg), Ca (0.67 ± 0.01 to 2.51 ± 0.19 mg), Mg (6.79 ± 0.19 to 24.99 ± 1.75 mg). Analyses of minerals and vitamins showed that Moringa oleifera leaf-powder (per 100 g) is rich in calcium (1443.90 ± 11.03 mg), magnesium (176.72 ± 0.73 mg), iron (53.75 ± 5.07 mg), zinc (17.58 ± 0.89 mg) and -carotene (624.40 ± 0.41 µg ER). 100 g of Parkia biglobosa’s pulps is rich in magnesium (73.00 ± 1.14 mg), iron (14.82 ± 2.49 mg), zinc (7.79 ± 0.44 mg) and vitamin C (75.29 ± 0.00 mg). In conclusion, we believe that these two ingredients can be effectively used to fortify local infant flours in vitamin A and iron and contribute to eradicating malnutrition due to micronutrients deficiencies.

UNLABELLED Palm wine produced traditionally and consumed by many people in the South-West of Burkina Faso is subject to alteration. In this study, we carried out a follow-up of two palm wines' fermentation during the 10 days in which palm wines are classically produced and consumed. We monitored biochemical characteristics of fermenting wines as well as followed the microflora kinetics using culture-dependent and culture-independent methods. The analysis of the acid content and the bacterial population revealed the correlation between the development of Lactic acid bacteria, acetic acid, and total acidity. Ribosomal intergenic spacer analysis and sequencing results revealed different yeast and bacterial populations for the two palm wines. Although Saccharomyces cerevisiae remained the sole yeast species in one fermentation, it was quickly replaced by Clavispora lusitaniae in the second fermentation, which had never been described until now in palm wine. When considering bacteria, the species Corynebacterium sp., Lactobacillus casei, Lactobacillus paracasei and Leuconostoc sp. were detected in both palm wines. But we also detected Acetobacter pasteurianus, Bacillus cereus and Bacillus thuringiensis in the second fermentation. SIGNIFICANCE AND IMPACT OF THE STUDY Our results highlight the evolution of palm wine during the 10 days separating palm tapping and consumption of the fermented wine. The fermentation step is performed within few hours and completed after 24 h. The next days, its acidity increases progressively with the production of lactic and acetic acids by bacteria. The high production of acetic acid is very likely one of the main cause of palm wine degradation during this period. This indicates that the solution to palm wine preservation might be protection against oxygen, as well as the limit of bacterial growth through the use of preservatives.

In this study, 67 strains were isolated from two fermented condiments from Burkina Faso: Soumbala and Bikalga. Phenotypical methods, biochemical tests and molecular approaches were used to determinate their genus or species. Twenty-two of them belong to the Bacillus genus. Six strains were selected for their antibacterial or antifungal properties. Their ability to produce lipopeptides synthesized by Non Ribosomal Peptide Synthetases was investigated using two different approaches: PCR with specific degenerated primers and Matrix-assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-ToF MS) performed on whole cells cultivated on a solid medium. PCR revealed that the six strains contain genes involved in the biosynthesis of surfactins whereas surfactins C14 and C15 were only detected by MALDI-ToF MS in two of the six strains. For the first time, the presence of surfactins C14 and C15 was also identified by MALDI-ToF MS analyses directly performed on Soumbala methanolic crude extracts. The structure of these compounds was confirmed by + MS2 and + MS3 of sample and reference surfactins.

Objectif: La presente etude a pour objectif la caracterisation physiologique de trois souches de moisissures S 1 , S 2 et S 3 isolees respectivement du mais, de l’arachide et du riz au biais de leur capacite a produire des enzymes extracellulaires. Methodologie et resultats: Au total, soixante-seize (76) echantillons d’aliments locaux ont ete collectes dans des marches centraux de trois villes du Burkina Faso. Deux cent soixante-douze (272) souches de moisissures ont ete isolees et soumises au criblage indirect de production d’enzymes extracellulaires. Il consiste a estimer la production par mesure de la vitesse de croissance apicale des souches fongiques sur des milieux solides supplementes par differents substrats carbones. Le criblage a revele l’activite proteolitique, amylolitiques, tannasiques, lipolitique et cellulosique de trois souches de moisissures. Selon les cles d’identification de Raper & Fennell (1965) et Pitt (1985), ces trois souches S 1 , S 2 et S 3 sont respectivement Aspergillus fumigatus , Aspergillus flavus et Penicillium citrinum . Conclusion et application: Les micro-organismes en general et les champignons en particulier constituent des sources d'enzymes plus facilement exploitables que celles des vegetaux ou les animaux a cause de la simplicite de purification. Les enzymes fongiques restent toujours les outils cles de la biotechnologie et refletent de plus en plus l’importance et le role infini des moisissures dans les differentes applications alimentaires. Parmi ces enzymes, les lipases, les phytases et les tannases sont percues comme etant des enzymes importantes en industrie. Cependant, le principal obstacle qui freine les applications potentielles de ces enzymes est leur cout. Des souches locales productrices d’interessantes enzymes pourraient contribuer a l’amoindrir. Mots cles: enzymes extracellulaires, aliments locaux, moisissures, milieu solide, croissance apicale English Title: The ability of three strains of fungi to produce extracellular enzymes on solid state in Burkina Faso English Abstract Objective: The aim of this study is the physiological characterization of three fungi strains S 1 , S 2 and S 3 respectively isolated from maize, groundnuts and rice through their ability to produce extracellular enzymes. Methods and Results: A total of seventy-six (76) samples of local foods were collected in centrals markets of three cities in Burkina Faso. Two hundred and seventy-two (272) fungi strains were isolated and submitted to extracellular enzymes indirect screening production. It was consisted by measuring the apical growth rate of the fungi strains on solid media supplemented with various carbon substrates. The screening revealed the proteolytic, amylolitic, tannasic, lipolytic and cellulosic activities of three fungi strains. According to the Raper & Fennell (1965) and Pitt (1985) identification key, these three strains S 1 , S 2 and S 3 are respectively Aspergillus fumigatus , Aspergillus flavus and Penicillium citrinum . Conclusion and Application: Micro-organisms in general and filamentous fungi in particular are rich sources of enzymes more easily exploitable than those of plants or animals due to the simplicity in purification. Fungal enzymes remain biotechnology key tools and reflect increasingly important and the infinity role of mold in various food applications. Among these enzymes, lipases, phytases and tannases are perceived as important enzymes in industry. However, the main obstacle hindering the potential applications of these enzymes is their cost. Local fungi strains with interesting enzymes property could help cost decreasing. Keywords: extracellular enzymes, local foods, fungi, solid state, apical growth

Degue was a traditional fermented food (pearl millet dough) which consumed in Burkina Faso. In this work, the traditional processing of pearl millet into degue was investigated in 18 traditional production units. This study was followed in Ouagadougou and Bobo-Dioulasso. The main steps of diagram of production were dehulling, winnowing, washing, drying, milling, sieving, kneading, cooking, pounding, shaping and fermentation. Before fermentation, crude protein, crude fat, ash, starch and carbohydrates content were respectively 5.43; 3.00; 1.13; 33.37 and 41.81 %. After 72 hours of fermentation only protein content (6.12 %) was increased; starch content was(23.6 %) decreased. pH and titratable acidity were respectively 6.75 and 0.12 before the fermentation and after 72 hours pH (4.49) was decreased and titratable acidity (0.57 g of 100 grams of lactic acid) was increased. Microbiology analyses indicated that the number of lactic acid bacteria, yeasts and moulds increased during the course of fermentation. The number of coliforms was decreased slightly after 72 hours of fermentation.

Aim: To quantify and identify the predominant lactic acid bacteria (LAB) in dolo and pito wort processing, and to examine their biodiversity at strain level. Materials and Results: The processing of dolo and pito wort was studied at four production sites in Burkina Faso and Ghana. The succession of dominant micro-organisms, pH and titratable acidity were determined from sorghum malt through mashing and acidification to final wort. In the sorghum malt and during mashing, the LAB counts were 5·7–7·5 log CFU g−1. Similar levels of yeasts and gram-negative, catalase-positive bacteria were observed. These levels decreased to 3·7–4·5 log CFU g−1 and ≤2–3 log CFU g−1, respectively, at the end of mashing, including a mild heat treatment. During acidification at ambient temperature (30–33°C) lasting for 12–16 h, LAB counts increased to 8·8–9·9 log CFU g−1, pH decreased from 5·55 ± 0·12 to 3·72 ± 0·24, and the titratable acidity calculated as lactic acid, increased from 0·13% to 0·61%. The gram-negative, catalase-positive bacteria and yeasts observed in the malt and during mashing were no longer detected. A total of 556 strains of LAB were isolated and purified. The LAB isolates were characterized and identified by a polyphasic approach based on phenotypic and genotypic methods, such as carbohydrate fermentation patterns using API 50 CHL, intergenic transcribed spacers–polymerase chain reaction/restriction fragment length polymorphism (ITS-PCR/RFLP), pulsed-field gel electrophoresis (PFGE) and 16S rRNA gene sequencing. Lactobacillus fermentum was identified as the dominant LAB species in the malt during mashing and during acidification. The other species observed during acidification were Lactobacillus delbrueckii ssp. delbrueckii, Lact. delbrueckii ssp. bulgaricus and Pediococcus acidilactici. These bacteria comprised a minor fraction of the bacterial population and no distinct microbial succession was observed for the LAB. At species level, the LAB profiles were similar for the four production sites; however, a pronounced diversity was observed at strain level. For one site, which had implemented a cleaning procedure between batches only, Lact. fermentum was found. Conclusion: Lact. fermentum was found to be the dominant LAB species throughout the entire process to final dolo and pito wort, including the acidification. Lact. delbrueckii ssp. delbrueckii, Lact. delbrueckii ssp. bulgaricus and P. acidilactici occurred in low numbers. At strain level, a high diversity based on PFGE–RFLP was observed for Lact. fermentum within and between sites. Significance and Impact of the Study: This study for the first time gives details of the involvement of LAB in the production of dolo and pito wort, for West African traditional sorghum beer production. One species, Lact. fermentum was predominant throughout the process, and seems to harbour potential starter cultures to be selected according to technological characteristics determined at strain level.

Three different processes combining cooking (C), addition of malt (M) and/or backslop inoculation (I) were investigated to increase the energy density (ED) of ben-saalga , a millet-based fermented gruel and their effects on fermentation kinetics and microbiological characteristics were assessed. In the process combining cooking and inoculation (CI) and in the control (traditional processing methods), glucose and fructose were the main sugars and their concentrations decreased during the settling step (fermentation). In the process combinations that included the addition of malt (CM and CMI), maltose was the main sugar that accumulated during settling. In the CM process combination, the start of fermentation was considerably delayed due to the marked reduction in natural microflora during cooking. In contrast, in the CI and CMI process combinations, inoculation by back slopping accelerated acidification, resulting in a pH value of below 4.0 after 7 h of fermentation. Although malt was added at a very low rate (0.125%), gruels made using CM and CMI process combinations, and prepared at a suitable consistency, had an ED close to or above 84 kcal/100 g of sweetened gruel, the minimum value required for complementary food.

The process of red sorghum malt production was monitored three times in five production units (PU) selected upon their ability to produce malt flours having a high capacity to fluidify high-energy-density gruels. Raw, germinated and degermed seeds were analysed for macronutrient, soluble sugars, phytate and cyanide contents and alpha-amylase activity. Know-how differences between producers lay mainly in the duration and type of equipment used for steeping and germination. Moreover, three PUs applied a maturation step before sun-drying and one PU added ashes to steeped seeds before germination. No significant difference was detected in the proximate composition of malts from the five PUs. For all PUs, traditional malting increased the protein content and decreased the lipid and ash contents, while the fibre content was not affected. Significant increases in sugar contents and in alpha-amylase activity were observed but in variable proportions from one PU to another. The phytate content decreased significantly in all PUs. The cyanide content increased in all PUs but more drastically or less drastically according to the PU. Finally, degerming lowered the cyanide content to an acceptable level for human consumption. The between-PU variability may be due either to the nature and origin of the raw seeds or to technological know-how differences between producers. Further investigations are needed to optimize and standardize the malting process with a view to maximizing alpha-amylase and phytase activities and minimizing the variability of their biochemical characteristics.

Fifty sorghum varieties were screened to determine the effects of germination on levels of starch, α-amylase, β-amylase, phenylalanine ammonia lyase (PAL), peroxidase (POX) and polyphenol oxidase (PPO). Germination decreased starch content, with amylose being more degraded than amylopectin. In germinated grain, α-amylase activity increased several-fold in all varieties, whereas β-amylase activity did not increase uniformly and even decreased in some varieties. Activity of the key enzyme in phenolic biosynthesis, PAL, was detected in only half of the varieties before germination but in all of them after germination. PPO was not activated in germinated sorghum grains, whereas POX activity increased up to tenfold in some varieties. Zymography revealed that germination induced de novo synthesis of several POX isoenzymes, among which an anionic POX isoenzyme (pI 3.1) was ubiquitously present. Amylase and phenolic enzyme activities could be correlated with grain and plant agronomic characteristics. The use of sorghum varieties for local dishes such as 'to', 'dolo', couscous and thin porridge could be correlated with amylase and phenolic enzyme activities and the contents of their substrates. The biochemical constituents determined are useful markers for selection of varieties for food utilisation with special emphasis on infant porridges.

Contents of phenolic compounds and related enzymes before and after sorghum grain germination were compared between varieties either resistant or susceptible to biotic (sooty stripe, sorghum midge, leaf anthracnose, striga, and grain molds) and abiotic (lodging, drought resistance, and photoperiod sensitivity) stresses. Independent of grain germination, sorghum varieties resistant to biotic and abiotic stresses had on average higher contents of proanthocyanidins (PAs), 3-deoxyanthocyanidins (3-DAs), and flavan-4-ols than susceptible varieties. Results show that content of 3-DAs is a good marker for sorghum resistance to both biotic and abiotic stresses because it correlates with resistance to all stresses except for photoperiod sensitivity. The second good marker for stress resistance is content of PAs. Total phenolic compounds and the activities of related enzymes are not good markers for stress resistance in sorghum grains.

Aims: To investigate predominant isolates of Bacillus subtilis and B. pumilus in soumbala, a fermented African locust bean condiment, for their ability to degrade African locust bean oil (ALBO). Methods and Results: Agar diffusion test in tributyrin and ALBO agar was used for screening of the isolates for esterase and lipase activity, respectively. The quantity and the profile of free fatty acids (FFA) during 72 h of degradation of ALBO by the Bacillus isolates were studied by titration and gas chromatography. The degradation of tributyrin and ALBO was variable among the isolates. Two strains of B. subtilis and two strains of B. pumilus showed significantly higher esterase and lipolytic activities than the others. The degradation ALBO was most pronounced in enriched nutrient agar except for one isolate of B. pumilus degrading ALBO to the same extent regardless of the enrichment. The quantity of FFA released from ALBO by the most lipolytic strains of Bacillus increased mainly between 0 and 24 h and differed among the isolates. The profile of FFA was similar for the Bacillus isolates with oleic acid (C18:2) occurring as the major FFA in all the samples except in samples incubated with B. subtilis B9 where stearic acid (C18) was dominant. Conclusion:Bacillus isolates from soumbala showed high strain dependent lipolytic activity against ALBO. Significance and Impact of the Study: This study contributes to the selection of Bacillus strains to be used as starter cultures for controlled production of soumbala.

Spacer region between 16S and 23 S rRNA genes of thirteen lactic acid bacteria strains from Burkina Faso fermented milk samples were amplified by the polymerase chain reaction (PCR). Lactobacillus delbrueckii, Lactobacillus acidophilus, Lactobacillus fermentum, Streptococcus thermophilus, Pediococcus spp, Leuconostoc mesenteroides subsp mesenteroides were identified. The Lactobacillus group was the predominant bacteria. Plasmids identified ranged between 2000 and 4000 bp. Exopolysaccharides (EPS) production varied from 181 mg/l and 814 mg/l, monomer analysis showed that glucose and galactose were predominant. Key Words: Lactic acid bacteria, fermented milk, PCR, exopolysaccharides. African Journal of Biotechnology Vol.3(3) 2004: 189-194

Analysis of fifty sorghum [Sorghum bicolor (L.) Moench] varieties used in Burkina Faso showed that they have different contents of phenolic compounds, peroxidase (POX), and polyphenol oxidase (PPO). Most of the varieties (82%) had a tannin content less than 0.25% (w/w). POX specific activity was higher than the monophenolase and o-diphenolase specific activities of PPO. For POX, there was a diversity of isoforms among varieties. No clear correlation could be made between the quantitative composition of the grain in phenolics, PPO, and POX, and resistance of plant to pathogens. In general, varieties good for a thick porridge preparation (“to”) had low phenolic compounds content and a medium POX activity. From the red varieties, those used for local beer (“dolo”) had a high content in phenolic compounds and PPO, and a low POX activity. The variety considered good for couscous had a low POX content. The characteristics might be useful as selection markers for breeding for specific applications. Keywords: Phe...

The leaves of Boscia senegalensis are traditionally used in West Africa in cereal protection against pathogens, pharmacologic applications, and food processing. Activities of alpha-amylase, beta-amylase, exo-(1--3, 1--4)-beta-D-glucanase, and endo-(1--3)-beta-D-glucanase were detected in these leaves. The endo-(1--3)-beta-D-glucanase (EC 3.2.1.39) was purified 203-fold with 57% yield. The purified enzyme is a nonglycosylated monomeric protein with a molecular mass of 36 kDa and pIor = 10.3. Its optimal activity occurred at pH 4.5 and 50 degrees C. Kinetic analysis gave Vmax, kcat, and Km values of 659 U/mg, 395 s(-1), and 0.42 mg/mL, respectively, for laminarin as substrate. The use of matrix-assisted laser desorption ionization time-of-flight mass spectrometry and high-performance liquid chromatography revealed that the enzyme hydrolyzes not only soluble but also insoluble (1--3)-beta-glucan chains in an endo fashion. This property is unusual for endo-acting (1--3)-beta-D-glucanase from plants. The involvement of the enzyme in plant defense against pathogenic microorganisms such as fungi is discussed.

Curculigo pilosa is traditionally used in the manufacture of sorghum beer in West Africa. β-Amylase was purified 100-fold with 38% yield from a crude extract, giving final specific activities of 4850 U/mg and 5650 U/mg using soluble starch and p-nitrophenyl maltopentaoside, respectively, as substrates. The molecular mass of the monomeric enzyme was 64 kDa and its pI 4.2. Both activity and thermostability are higher than reported for other plant β-amylases. The catalytic efficiency was lower for amylose than for starches and amylopectin. In contrast to other plant amylases, the β-amylase from C. pilosa is able to degrade raw starches from wheat, corn, potato and rice. In this respect, it resembles β-amylases from microbial origin. This property, and its high activity and stability, explain its traditional use in the manufacture of infant food and sorghum beer in Burkina Faso and could make it applicable for other biotechnological purposes.

In a wetland ecosystem such as lowland ricefields, the anaerobic mineralization of organic matter is a key mechanism for nutrient recycling (Jorgensen 1982; Freney et al. 1982). In the process which involves several bacterial groups, sulfate reducers (Watanabe and Furusaka 1980; Widdel 1988; Ouattara and Jacq 1992; Nozoe 1997), methanogens (Asakawa and Hayano 1995; Dianou et al. 1997), sulfur and ferric ion reducers (Jacq et al. 1991) become active when the soil becomes anoxic (Amstrong 1969). Sulfate reducers are common in flooded soils (Watanabe and Furusaka 1980; Widdel 1988; Furusaka et al. 1991). Reported densities in rice soils ranged from 103 to 105 g-1 dry soils in Asia (Watanabe and Furusaka 1980) and from 102 to 109 g-1 dry soil in Senegal (Ouattara and Jacq 1992). Among the sulfate reducers, the “classical” Desulfovibrio species are known to oxidize typical fermentation products such as hydrogen, lactate, pyruvate, and dicarboxylic acids (Widdel 1988). So far, data on the isolation and...

In wetland ecosystems, such as rice fields, methanogenic bacteria (MB) play important roles in global carbon cycling as terminal organic decomposers and in hydrogen cycling as hydrogen consumers, leading to methane production (Jorgensen 1982). In the global atmosphere, concentration of methane has been increasing by about 1% per year (Blake and Rowland 1986; Bouwman 1989; Dlugokensky et al. 1994) and it is considered that 80% is of biological origin (Seiler 1984). The environmental impact of methane on global warming has also been confirmed (Chappellaz et al. 1990). Rice paddy fields contribute to an estimated 10% of the global methane emission (Bouwman 1989; IPCC 1992) and the intensification of paddy cultivation may contribute considerably to the gradual increase of atmospheric methane (Rasmussen and Khalil 1981). From 1970 to 1990, rice production increased by 110% in West Africa (FAO 1970, 1990), as a direct result of encroachment on new lands throughout most of West Africa (Windmeijer and An...

The cytotoxic and anti-Mycobacterium tuberculosis H37Rv activities of hydro-alcoholic extract of Lannea acida A. Rich (Anacardiaceae) were assessed. The cytoxicity evaluation was carried out on THP1 monocytoid cell line (after 24 h at 1; 5 and 10 microg mL(-1)) and showed only a slight modification of lactate dehydrogenase (LDH) release. The rate of monocytes in different stages of mitosis had been amended in absence and presence of extract as follows: Go/G1 58.83-59.83%; synthesis 21.95-18.64%; mitosis 16.67-15.77%; necrosis 2.65-5.64%. The percentage of inhibition of Mycobacterium tuberculosis proliferation was respectively 77.6 and 36.8% at 1.2 and 0.6 mg mL(-1) of extract. This is an interesting experimental study on antimicrobial and immune-stimulating properties of Lannea acida ethanol-water (70% v/v) extract which may contain potential antibacterial and immune-stimulating agents for clinical use.

The antioxidant activity of the essential oil was investigated using 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging assay and the -carotene bleaching test. Butylated hydroxytoluene (BHT) was employed as a positive control. The essential oil showed antioxidant and DPPH radical scavenging activities, and it displayed the inhibition of lipid peroxidation. The antibacterial and antifungal activities of the essential oil of Canarium schweinfurthii from Centrafrican Republic were also evaluated against twelve strains of bacteria and three strains of fungi using agar diffusion and broth microdilution methods. The essential oil showed antimicrobial activity against almost the strains studied. The results suggest that C. schweinfurthii essential oil could be a natural antimicrobial and antioxidant agent.

An anaerobic digester fed with shea cake rich in tannins and phenolic compounds rich-shea cake and previously inoculated with anaerobic sludge from the pit of a slaughterhouse, enabled six months acclimatization of the bacteria to aromatic compounds. Afterwards, digester waste water samples were subject to successive culture on media with 1 g L(-1) tannic acid allowing the isolation of a bacterial strain coded AB. Strain AB was facultatively anaerobic, mesophilic, non-motile, non-sporulating, catalase and oxidase negative bacterium, namely strain AB, was isolated from an anaerobic digester fed with shea cake rich in tannins and phenolic compounds, after inoculation with anaerobic sludge from the pit of a slaughterhouse and enrichment on tannic acid. The coccoid cells occurred in pair, short or long chains and stained Gram-positive. Strain AB fermented a wide range of carbohydrates including glucose, fructose, galactose, raffinose, arabinose, sucrose, maltose, lactose, starch and cellulose. Optimum growth occurred with glucose and tannic acid at 37 degrees C and pH 8. The pH, temperature and salt concentration for growth ranged from 5 to 9, 20 to 45 degrees C and 0 to 15 g L(-1), respectively. Strain AB converted tannic acid to gallic acid. These features were similar to those of the Streptococcus genus. The determination of tannic acid hydrolysis end products, ability to utilize various organic acids, alcohols and peptides, GC% of the DNA, the sequencing of 16S rRNA gene and DNA-DNA hybridization will permit to confirm this affiliation and to determine the species.

A sulfate-reducing bacterium, strain HDv, was isolated from the anoxic soil of a ricefield using lactate as electron donor. Cells were gram-negative, motile, nonsporulating curved rods, with single polar flagella. Substrates were incompletely oxidized to acetate and included glycerol, 1,2- and 1,3-propanediol. Sulfate, sulfite, thiosulfate, elemental sulfur, fumarate, maleate, and malate were utilized as electron acceptors. Pyruvate, fumarate, maleate, malate and dihydroxyacetone were fermented. Desulfoviridin and c-type cytochromes were present. The DNA base composition was 66.6 +/- 0.3 mol% G+C. The isolate was identified as a Desulfovibrio sp.; its metabolic properties were somewhat different from those of previously described Desulfovibrio species. Comparative biochemical study of 1,2-propanediol dissimilation by the new isolate and Desulfovibrio alcoholovorans showed that NAD-dependent dehydrogenases play a key role in the catabolism of this substrate. The hypothetical pathways of 1,2-propanediol degradation by Desulfovibrio spp. are presented.

A strictly anaerobic, gram-negative bacterium was isolated from rice field soils by using lactate as a sole carbon and energy source. The cells were non-spore-forming, motile, curved rods. Optimal growth occurred at 35°C and pH 6.8. No NaCl requirement was observed. Vitamins were required for growth. Our isolate, strain B4B0 T (T = type strain), fermented pyruvate, fumarate, malate, citrate, dihydroxyacetone, fructose, 1,2-propanediol, glutamate, and aspartate to acetate, propionate, succinate, and traces of hydrogen. Strain B4B0 T did not use ribose or glycerol as an energy source, although glycerol degradation produced mainly 1,3-propanediol. Ferric iron was facultatively reduced. Nitrate and sulfate were not reduced. Cytochrome b was present. The guanine-plus-cytosine content of the DNA was 44.1 ± 0.1 mol%. We propose that strain B4B0 (= DSM 6283) should be the type strain of a new species in the genus Anaerovibrio, Anaerovibrio burkinabensis.

Calotropis procera is a bush latex plant, 1–3 m high; its leaves are 10–13 cm wide by 17–19 cm long. This plant is very drought-resistant and grows throughout the Sahelian countries, notably in Burkina Faso. Batch fermentation experiments show that it is a good substrate for biogas production. The highest productivities obtained varied from 2·9 to 3·6 litres biogas day −1 litre −1 when the digester loading was a 4% (w/v) suspension of dry leaves at initial pH 7·5. The acidogenic step of the fermentation was very fast, about 66% of dry material loaded being degraded during the first 2 days of incubation at 30°C. The resulting biogas contained 56–59% (v/v) methane.

The screening of 50 sorghum varieties showed that, on average, germination did not affect the content in total phenolic compounds but decreased the content of proanthocyanidins, 3-deoxyanthocyanidins, and flavan-4-ols. Independent of germination, there are intervarietal differences in antioxidant activities among sorghum varieties. Phenolic compounds and antioxidant activities were more positively correlated in ungerminated varieties than in germinated ones. Sorghum grains with pigmented testa layer, chestnut color glumes, and red plants had higher contents, larger diversity of phenolic compounds, and higher antioxidant activities than other sorghums. Some red sorghum varieties had higher antioxidant activities (30-80 Imol of Trolox equiv/g) than several sources of natural antioxidants from plant foods. Among varieties used for “to ˆ”, “dolo”, couscous, and porridge preparation, the “dolo” (local beer) varieties had the highest average content and diversity in phenolic compounds as well as the highest antioxidant activities. The biochemical markers determined are useful indicators for the selection of sorghum varieties for food and agronomic properties.

Traditional cereal-based fermented foods are frequently used as complementary foods for infants and young children in Africa. This is the case for ben-saalga, a popular fermented gruel produced from pearl millet (Pennisetum glaucunt) in Burkina Faso. Detailed knowledge of traditional processing is a prerequisite for investigating ways to improve both the nutritional and sanitary qualities of the corresponding foodstuff. In this work, the traditional processing of pearl millet into ben-saalga was investigated in 24 production units, and fermentation kinetics were studied in pilot scale experiments. Processing steps include: washing (optional), soaking of the grains (first fermentation step), grinding and sieving of the wet flour, settling (second fermentation step), and cooking. The soaking step was mainly characterized by alcoholic fermentation whereas lactic acid fermentation occurred during the settling step. Fermentation kinetics during settling indicates a temporal variation of metabolic activity. Initially, both homofermentative and heterofermentative pathways were simultaneously active, and later only a homofermentative pathway was active. The paste produced at the end of settling had a low pH (4.0 +/- 0.4) and its microflora was dominated by lactic acid bacteria (LAB) with an amylolytic LAB/LAB ratio of 12%. Sucrose disappeared in the grains during soaking but was not detected in the soaking water, whereas glucose, fructose and maltose appeared transiently. Glucose and fructose were the main substrates observed for lactic acid fermentation during the settling step; however unbalanced fermentation led to the hypothesis that starch hydrolysis products may also serve as substrates for lactic acid formation. At the end of the processing, a 75% and 83% decrease was observed in phytate (IP6) and raffinose, respectively. The sour gruel ben-saalga resulting from cooking the sour paste had inadequate nutritional characteristics with respect to infants' and young children's requirements; it was characterized by fluid consistency (Bostwick flow: 137 mm/30 s) and low energy density (about 30 kcal/100 g of gruel). (c) 2005 Elsevier B.V. All rights reserved.

A syntrophic consortium was enriched in a basal medium containing cinnamate as the carbon and energy source. It was found to consist of three morphologically distinct microbes, viz., a short, rod-shaped, non-motile bacterium with distinctly pointed ends, Papillibacter cinnamivorans; a rod-shaped, motile bacterium with rounded ends, Syntrophus sp.; and a methanoarchaeon, Methanobacterium sp. This methanogen was then replaced by a collection strain of Methanobacterium formicicum. A syntrophic interdependency of the three partners of the consortium was observed during growth on cinnamate. In the presence of bromoethanesulfonic acid (BESA), cinnamate was transformed to benzoate, whereas under methanogenic conditions without BESA, cinnamate was first transformed to benzoate via beta-oxidation and subsequently completely degraded into acetate, CH(4), and CO(2). Papillibacter cinnamivorans was responsible for benzoate production from cinnamate, whereas a syntrophic association between Syntrophus sp. and the methanogen degraded benzoate to acetate, CH(4), and CO(2). A new anaerobic degradation pathway of cinnamate into benzoate via beta-oxidation by a pure culture of P. cinnamivorans is proposed.

This article is free to read on the publishers website A sulfate-reducing bacterium, strain HDvT(T = type strain), was isolated from an anoxic ricefield soil. Cells were Gram-negative, non-sporulating curved rods motile by means of a single polar flagellum. Cytochrome c3 and desulfoviridin were present. In the presence of sulfate, glycerol, 1,2- and 1,3-propanediol, dihydroxyacetone, pyruvate, lactate, fumarate, maleate, malate and succinate were incompletely oxidized mainly to acetate. Sulfite, thiosulfate, elemental sulfur, fumarate, maleate and malate were utilized as alternative electron acceptors. In the absence of added electron acceptors, pyruvate, fumarate, maleate, malate and dihydroxyacetone were fermented. The DNA base composition was 67 mol% G+C. The phylogenetic, phenotypic and physiological characteristics of strain HDvTindicate that it is a new species of the genus Desulfovibrio, for which the name Desulfovibrio burkinensis sp. nov is proposed; the type strain is HDvT (= DSM 6830T). Phylogenetic analysis confirmed that Desulfovibrio alcoholivorans was a distinct species supporting the previously published phenotypic data.