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The objective of this study was to evaluate the anti-nutrient and organic acid content of the seeds of three legumes of the genus Canavalia according to their maturity stage. The biological material used for the laboratory operations consisted of seeds and pods at different stages of maturity harvested from a field in the Gbèkê region, central Côte d'Ivoire. Seeds of the three cultivars were harvested at different stages of maturity: 30 days (S1), 40 days (S2), 50 days (S3), 60 days (S4) and 80 days (S5) after fertilisation. The seeds are dried and ground to obtain the raw meal. The content of anti-nutrient compounds was studied using standard colorimetric methods, while the distribution of organic acids was carried out using HPLC analytical methods. The composition of anti-nutrients showed that their content decreased during ripening from stage S1 to stage S5 with the lowest contents, respectively for Canavalia gladiata, Canavalia rosea and Canavalia ensiformis being : 33.49 ± 0.06, 32.06 ± 0.06, 21.23 ± 0.06 mg/100g DM for phytates; 257.15 ± 0.06, 141.48 ± 0.07, 177.42 ± 0.06 mg/100g DM for oxalates; 1.39 ± 0.05, 1.67 ± 0.01, 1.09 ± 0. 01 mg/100g DM for saponin; 449.17 ± 5.54, 442.50 ± 5.38, 546.67 ± 2.98 mg/100g DM for L-dopamine and 98967.42 ± 3.27, 866.71 ± 3.19, 437.67 ± 1.99 trypsin units inhibited by trypsin inhibitors. With regard to the content of organic acids at all stages of maturity, it is noted that the predominant for the extracts of C. gladiata and C. rosea is lactic acid (0. 05 to 3.68 mg/kg DM and 0.03 to 4.02 mg/kg DM) followed by acetic acid (0.03 to 3.06 mg/kg DM and 0.01 to 2.11 mg/kg DM) and oxalic acid (0.01 to 2.76 mg/kg DM and 0.01 to 1.54 mg/kg DM).

In Côte d'Ivoire, cashew apples represent waste in plantations due to lack of processing. This study deals with their transformation into jam for a better valorization. Cashew apple jam were analyzed for physicochemical and sensory properties. Proximate physiochemical were determined using standard analytical procedures and the sensory acceptance test was performed by 50 panelists on the following attributes. Proximate result showed that moisture content of cashew apple jam was 26.5±1.77% ; carbohydrate 67.7±02.45%, protein 0.7±0.01%; fat and ash contents were 0.16±0.0 and 2.4±0.01% for respectively. pH and titratable acidity were 3.9±0.01 0.06% respectively. Soluble solids (°Brix) was 25±0.98%. Vitamin C and total sugar contents were 276±4.67 (mg/100g) and 51.87±2.18% respectively. Major minerals in the jam were potassium (2762±43.2 mg/Kg), phosphorus (298±4.1 mg/Kg), magnesium (146±1.1 mg/Kg) and calcium (143±2.21mg/Kg). phytochemical analysis revealed presence of tannins (0.8±0.01%), phenol (0.35±0.02%), oxalate (1.87±0.02%) carotenoids (0.70±0.01%), flavonoid (0.20±0.01%), phytate (1.16±0.03%) Results from sensory analysis showed color (7.88±0.55), consistency (8.22±0.83), sweet (8.44±1.09) odour (5.4±0.36) and general acceptability 5.22. Parameters (acidity, astringency and afteraste) scores are less than 3.

Polygalacturonases are extensively used in food industries for pectic substances degradation. In this paper, we investigate on thermal stability parameters of two Polygalacturonases previously isolated from digestive juice of the snail Limicolaria flammea for several industrial applications such as fruit juice clarification. Thermal inactivation was carried out in the temperature range of 55°C to 80°C from 15 to 120 min. All results were statistically analysed. The results shown that thermal inactivation of studied acid phosphatases follows first order kinetics. At their optimum temperatures, these enzymes showed high half-lives ranging from 462.06 to 630.10 min and D values from 1535.00 to 2093.64 min suggesting that these two enzymes had a large thermal stability. The high values of ΔG# (93.96 to 94.97 kJ/mol) reveal a better resistance to denaturation. The relatively high activation energies (from 120.35 to 129.13 kJ/mol) and average enthalpy values (from 117.67 to 126.44 kJ.mol−1) could corroborate the good stability of these biocatalyst. All these results suggest that Polygalacturonases from digestive juice of the snail Limicolaria flammea may be profitably exploited in future food industrial applications.

Objective: The present study aims to constitute a database necessary for the efficient valorisation of the local cultivated edible mushrooms in the Ivorian diet. This work consisted in evaluating the biochemical characteristics and microbiology analysis of cultivated Pleurotus ostreatus species sold and used in rural and urban people food. Methodology: Standard methods proposed by AOAC made this study possible to determine the biochemical parameters such as dry matter, ash, pH, moisture, protein and lipid content. The microbiological analyses enabled the enumerations of yeasts and molds, fecal coliforms, aerobic mesophilic germs, detection and enumeration of Escherichia coli and Salmonella were performed. Results: The results showed that the cultivated Pleurotus ostreatus is a food, rich in protein (16.37 ± 0.6 % dw), crude fibre (24.85 ± 0.08 dw) and in ash (11.00 ± 1.33 % dw). On the other hand, this mushroom is relatively low in lipids (4.16 ± 0.13% dw) and reducing sugars (1.04 ± 0.07 % dw) with a low moisture content (6.40 ± 1.13 % dw). These results also revelated the absence of Salmonella and Escherichia coli in the flour. Conclusion: Local cultivated Pleurotus ostreatus mushroom is an undeniable source of protein and crude fibre. Thus it would be used as a substitute for meat diet, allow a good functioning of the immune system and the good development of bones. It also show satisfactory microbiological criteria. Thus Pleurotus ostreatus mushroom is a safety food for ivorian.

Aims: During the industrial processing of mango, considerable quantities of peel and seeds are rejected, which results in a significant economic loss for the manufacturer, as well as an impact on the environment. However, mango almond and peel flours present enormous nutritional and especially therapeutic potentialities. Thus, the objective of this work is to contribute to the valorization of the waste of 4 varieties of mango (Amelie, Kent, Keitt, Brooks) from north in Ivory Coast by the determination of their bioactive compounds in, order to be used in the pharmaceutical industry. Place and Duration of Study: Laboratory of Biochemistry and Food Technology, Nangui Abrogoua University, Abidjan 02, Ivory Coast. Between March 2019 to July 2021. Methodology: Phenolic compounds of the Mango almond and peel flours were extracted with ethanol. UV-VIS spectrophotometry was employed to further quantify the total phenolic, tannin and total flavonoid content. DPPH radical scavenging assay, 2.2-azino-bis (3-ethylbenzthiazoline-6- sulphonic acid (ABTS) scavenging test and ferric reducing antioxidant power (FRAP) were used to determine antioxidant activity. As for phenolic acids, they were analysed by HPLC. Well diffusion method was used to determine antibacterial activity. Results: The analysis of the bioactive compounds of these mango discards revealed that they are characterised by high contents of total polyphenols 39.67 ± 0.04 to 85.18 ± 0.01 mg/g in the peel and 22.86 ± 0.03 to 58.43 ± 0.00 mg/g in the almond, flavonoids 4.36 ± 0.03 to 20.43 ± 0.02 mg/g in peel and from 6.59 ± 0.01 to 26.72 ± 0.02 mg/g in almonds, tannins 5.04 ± 1.13 to 8.64 ± 0.76 mg/g in peel and from 6.58 ± 0.06 to 12.46 ± 0.11 in almonds. Antioxidant activity varies in peel and almond from 64.49 ± 2.56 to 96.40 ± 0.32 % and 89.16 ± 1.45 to 97.96 ± 0.25 % respectively for ABTS, from 59.51 ± 0.26 to 86, 27 ± 0.56% and 80.39 ± 0.56 to 87.21 ± 0.39% for DPPH inhibition and from 0.59 ± 0.0 to 0.72 ± 0.01 mg/g and from 0.81% to 0.92% mg/g for iron reduction by the FRAP method. As for the antimicrobial activity, very marked inhibition diameters were observed both with the peel extracts and in the almonds for different bacteria (B. ceurus, E. coli, ST. aureus, S. typhi, P. aeruginosa). Conclusion: These results demonstrate that the antimicrobial and antioxidant activities of the by-products of the four mango varieties are potential sources of bioactive compounds. These by-products could therefore be used in the pharmaceutical industry and diet.

The present study was aimed at investigating some biochemical properties, mineral contents and amino acid composition in seeds ofMucuna pruriensas a function of ripening stage. These seeds were harvested at different stages of maturation in a field carried out in the center of Côte d'Ivoire (Gbèkê Region). Seeds and pod were separated, and they were oven dried and ground to obtain the crude flour and analyzed according to standard procedures. Results showed that levels of dry matter (85.229-94.025 g.100g-1 dw), lipids (1.503-2.973 g.100g-1 dw), proteins (17.810-28.617 ± 0.296 g.100g-1 dw), fiber (6.483-7.477 g.100g-1 dw), ash (3.922 -9.231 g.100g-1 dw) and total sugars (10.338 -26.210 g.100g-1 dw) , increase significantly with the stage of maturity, while those of carbohydrates (70.282-51.703 g.100g-1 dw) and the energy value (365.893-348.037 Kcal.100g-1) decreases. Mineral analysis revealed that seeds are rich in essential minerals. Potassium (915.54- 20065.73 ug.100g-1) were the most abundant mineral, followed by magnesium (1335.33-16546.66 ug.100g-1), calcium (808.66-7739.39 ug.100g-1) and phosphorus (732.33-7440.00 ug.100g-1). The least abundant minerals were sodium (0.00-60.22 ug.100g-1), zinc (20.25-56.33 ug.100g-1), iron (41.63-475.52 ug.100g-1), copper (9.76-37.99 ug.100g-1) and manganese (0.00-5.94 ug.100g-1). For all assayed minerals, highest levels were founded in the seeds harvested 45 days after fertilization. Amino-acids profile has showed nutritionally useful amounts of essential amino acids such as histidine (18.32-40.81 mg.g-1 protein), isoleucine (30.76-66.35 mg.g-1 protein), leucine (72.47-103.51 mg.g-1 protein), lysine (27.22-57.28 mg.g-1 protein), methionine (25.51-51.74 mg.g-1 protein), threonine (10.91-37.40 mg.g-1 protein), tryptophan (29.22 -61.62 mg.g-1 protein) and valine (35.71-72.74 mg.g-1 protein). The study revealed M. pruriens seeds are rich in energetic and nutritional compounds. However, to optimize their nutritional qualities they may be harvest 35 days after the fertilization of the flowers.&nbsp

Mango almond and peel flours are a potential source of nutriment. In this study, the proximate composition and mineral element profile of four varieties of mango flour that are grown and processing in north of Cote d’Ivoire investigated. The data can be used as a reference when these flours are used for further processing in a variety of products. The peels and almonds were harvested fresh, dried in an oven at 50°C for 72 hours, ground and analysed according to standard procedures. Results showed carbohydrate, crude protein, total lipid, crude fibre, ash contents and vitamin C of the couple “peel – almond” flours were found to be 83.83-76.16%, 2.48-6.54%, 2.79-13.45%, 9.97-7.67%, 4.25-3.10% and a considerable amount of vitamin C of 307.67–304.85 mg/100g, respectively. They also contained important minerals such as calcium at 1204.45-1064.82 mg/100g, magnesium at 257.46-243.81 mg/100g, and potassium was the major at 1883.65-1617.66 mg/100g, regarding peels and almonds flours, respectively. Mangoes varieties such as Amelie, Kent, Keitt and Brooks have the potential to be a good source of nutrition for humans and animals. Mangoes varieties, peels, almonds, biochemical parameters, minerals.

Polygalacturonases constitute the major part of pectinase preparations for many bioprocess purposes. Investigation on the digestive juice of snail Limicolaria flammea led to purification of two polygalacturonases named PG1 and PG2. Properties of these enzymes were examined to explore their potential in biotechnology applications. A three steps procedure including size exclusion, anion and cation exchange and hydrophobic interaction chromatography were used for purification. The enzymes PG1 and PG2 had native molecular weights of approximately 46 and 86 kDa, respectively and functioned both as monomeric structures. The purified polygalacturonases PG1 and PG2 showed optimum hydrolysis activities at 50°C in sodium acetate buffer pH 5.6. The common inhibitor of the two purified polygalacturonases activity were Mn2+, Ca2+, Zn2+, EDTA, SDS and L-cystein. NH3+ stimulate the polygalacturonase PG1 while Ba2+ was an activator for polygalacturonase PG2. Substrate specificity indicated that these enzymes hydrolyse a broad range of pectin from different sources. The highest activity of PG1 was observed with apple pectin and lemon pectin while PG2 showed its highest activity with orange pectin. The catalytic efficiency of PG1 was highest for lemon pectin (0.125 µmol/min/mL) and orange pectin (0.124 µmol/min/mL). PG2 displayed highest catalytic efficiency (0.325 µmol/min/mL) towards orange pectin. These results suggest that orange and lemon pectin would be the potential physiological substrates of the two purified enzymes.

The aim of this study was to evaluate the chemical composition and mineral bioavailability of T. tetraptera fruit pulp, an aromatic wild edible plant, using standard methods. The pulp were extracted from mature dried fruits obtained from plants at Awabo (5°30‘14.2”N and 4°01‘30.6”W) and Loviguié villages (5°48‘24.5‘‘N and 4°20‘15.8”W), all in south-eastern Côte d‘Ivoire. The results of chemical analysis revealed that T. tetraptera fruit pulp contains carbohydrates (63.73±0.51%), crude protein (7.01±0.66%), crude fat (1.18±0.01%), ash (5.38±0.18%), fibre (11.78±0.02%), moisture (40.52±0.18%) and an energy value of 254.74±0.15 kcal/100g. Besides, the results showed a relative high amount of vitamin A (2.11±0.02%) and vitamin B9 (261.78±0.01 µg/100g) while vitamin E, B1 and B2 in trace concentration. Otherwise, the phytochemical analysis (mg/100g) based on dry weight revealed an appreciable amount of total phenol (2407.10±8.36), flavonoids (14.29±0.56), tannins (55.11±0.44), catechin (392.93±1.01) and also carotenoids (108.19±7.42 µg/100g). Organic acids profile (mg/100mL) showed citric acid (175.06±0.02) and salicylic acid (109.85±0.01) as major organic acids. Mineral composition (mg/100g) on dry weight basis revealed that potassium (1303.67±0.58) is the most abundant followed by phosphorus (303.33±5.77), calcium (187.33±0.58) and magnesium (141.33±0.57). Furthermore, the Phytates:Zn, Phytates:Ca, Oxalates:Ca and Phytates*Ca:Zn molar ratios recorded were all below than recommended threshold values, implying a bioavailability of zinc and calcium. These data indicate that the pulp of this fruit could be a good source of ingredient for both medicine and food industries in production.

Aims: Investigation on the phosphotransferase activity of two non-specific acid phosphatases (EC 3.1.3.2) designated as AP1 and AP2, previously isolated from breadfruit (Artocarpus communis) seeds for further biotechnological and industrial applications. Methodology: Transphosphorylation reactions were tested with sodium pyrophosphate as the phosphoryl donor and phenol as its acceptor. Transfer products were quantified by using high performance liquid chromatography. Results: The two acid phosphatases were able to catalyse phosphoconjugates synthesis using pyrophosphate as the phosphoryl donor and phenol as acceptor. The optimal conditions of transphosphorylation reactions indicated that this synthesis was highly dependent on pH, temperature, time course, donor and acceptor concentrations and enzyme amount. A very short period (1.25 h) was observed for these synthesis reactions catalysed by acid phosphatases isolated from breadfruit (Artocarpus communis) seeds. This suggested energy saving during biotransformation processes. The high average yields of 84.20 and 66.78% obtained for AP1 and AP2, respectively, made them useful to phosphorylate a wide range of nucleophile compounds such as nucleotides often used as food additives and pharmaceutical intermediates. Conclusion: The acid phosphatase AP1 would be the most promising on the basis the better synthesis product yield (84.20%). The two biocatalysts could be considered as new valuable tools for bioprocesses.

Impacts of cooking times (steaming and cooking on embers) on some physico-functional parameters of yam (D. bulbifera) flours cv Dougou-won were determined during 10, 20 and 30 min. Results showed that steaming and cooking on embers increased significantly (P

Palm weevil, Rhynchophorus palmarum L., is an important pest of palm trees (Elaeis guineensis) around the tropical regions. Characterization of their digestive enzymes could be an important stage to develop appropriate pest control strategies. Study of these enzymes could also be of interest in different biotechnological applications. Among digestive enzymes, there is β-glucosidase which hydrolytically catalyzes the β-glycosidic linkage of glycosides. In the present work, the catalytic activity of β-glucosidase in the digestive juice of last larval instar of R. palmarum L. (Rpbgl) has been investigated using p-nitrophenyl-β-D-glucopyranoside (pNPG) as substrate. The “classical” physico-chemical properties for purified Rpbgl have been determined by the help of enzymatic activity modeling. Thus, the values of (325.4 ± 0.2) K, 5.28 ± 0.07 and (37.9 ± 0.6) kJ mol−1 were obtained for optimum temperature, optimum pH and activation energy, respectively. The pK values for enzyme-substrate complex are 4.25 ± 0.07 and 6.20 ± 0.07 for nucleophile and the proton donor, respectively. Enzyme kinetics study was also performed and the values of (127 ± 6) U mg−1 and (0.78 ± 0.08) mM were obtained for Vmax and Km, respectively. Using the Equilibrium model (EM), the thermal inactivation data were analyzed. ΔHeq, Teq, ΔGinact∗ and ΔGcat∗ were found to be (222 ± 4) kJ mol−1, (323.0 ± 0.1) K, (101.9 ± 0.2) kJ mol−1 and (53.37 ± 0.02) kJ mol−1, respectively. These results show that Rpbgl is less stable with a narrow temperature tolerance compared to other β-glucosidases.

In this work, comparative study of physicochemical properties and fatty acids of dried arils (DA) oil and those roasted (RA), of Blighia sapida from Côte d’Ivoire have been done using usual methods. The results showed that the crude fat obtained were 59.08± 0.02 g/100 g for dried arils (DA) and 60.51 ± 0.12 g/100 g for roasted arils (RA) respectively. Physicochemical properties of these oils were equal approximately, except level of saponification (241.19 mg KOH/g (DA) against 216.8 mg KOH/g (RA)); acid value (7 mg KOH/g (DA) and 6.28 mg KOH/g (RA)) and ester acid 234.19 mg KOH/g (DA) against 210.65 mg KOH/g (RA) where variances analysis showed that there was significant difference (p

Objective Investigation on the phosphotransferase activity of two non-specific acid phosphatases (EC 3.1.3.2) designated as AP1 and AP2, previously isolated from breadfruit (Artocarpus communis) seeds for further biotechnological and industrial applications. Methods Transphosphorylation reactions were tested with sodium pyrophosphate as the phosphoryl donor and phenol as its acceptor. Transfer products were quantified by using high performance liquid chromatography. Results The two acid phosphatases were able to catalyze phosphoconjugates synthesis using pyrophosphate as the phosphoryl donor and phenol as acceptor. The optimal conditions of transphosphorylation reactions indicated that this synthesis was highly dependent on pH, temperature, time course, donor and acceptor concentrations and enzyme amount. A very short period (1.25 h) was observed for these synthesis reactions catalyzed by acid phosphatases isolated from breadfruit (Artocarpus communis) seeds. This suggested energy saving during biotransformation processes. The high average yields of 84.20 and 66.78% obtained for AP1 and AP2, respectively, made them useful to phosphorylate a wide range of nucleophile compounds such as nucleotides often used as food additives and pharmaceutical intermediates. Conclusion The acid phosphatase AP1 would be the most promising on the basis the better synthesis product yield (84.20%). The two biocatalysts could be considered as new valuable tools for bioprocesses.

In Cote d’Ivoire, malnutrition is still a public health problem. To remedy this, international institutions involved in this fight recommend the promotion of local resources rich in proteins such as insects and caterpillars. Thus, this study aims to enhance the enrichment of sorghum toh with shea caterpillar flour (Cirina butyrospermie) in order to solve the problems of malnutrition. To do so, 25 young rats of Wistar strain, aged to 50±05 days with an average weight between 45 and 55±5 g were divided into 5 batches were fed respectively with toh formulated with 5%, 10% and 15% of shea caterpillar flour during 15 days. At the end of this period, the nutritional parameters were calculated and biometric study was conducted to evaluate the impact of enriched food on well-being of young rats. The results obtained reveal interesting nutritional potentialities in most parameters. For example, the weight gains obtained varied from 4.86±0.45 g/d to 6.05±0.39 g/d in to rats fed with different formulations of toh enriched with shea caterpillar flour and the diet STScF2 did not show any significant difference with control diet. In terms of biological value, values obtained vary from 84.12% to 90.64% while those of protein retention vary from 11.66±1.85 g to 12.99±0.89 g respectively for young rat fed with diets STScF3 and STScF1. Concerning biometric study, no abnormality was noted following the consumption of these foods. In view of the nutritional potential developed by young rats, the toh enriched with 10% shea caterpillar four, could be retained to solve malnutrition problems.

The aim of this study was to investigate the phenolic compounds content, HPLC-profiles of phenolic compounds and organic acids, and also antioxidant activities via the ability to scavenge DPPH radical of three wild edible mushrooms belonging to Russula genus and being collected in center of Cote d’Ivoire. Total phenolic compounds, flavonoids and tannins contents of methanolic extracts were assessed by colorimetric assays. So, the obtained values of these chemical parameters ranged from 394.05 to 513.50 mg/100 g DW, 94.50 to 139.95 mg/100 g DW and from 124.20 to 165 ± 0.54 mg/100 g DW, respectively. Otherwise, HPLC-profiles of the methanolic extracts revealed that quercetin, salicylic acid and tannin ol were the main phenolic compounds in R. delica whereas R. lepida contained gallic acid, catechin and protocatechuic acid as main phenolic compounds. Besides, it showed that the phenolic compounds such as salicylic acid, tannin ol and catechin were observed in R. mustelina. As for HPLC-profiles of organic acid, the fumaric and malic acid were recorded as the main organic acids in the three species of wild edible mushrooms. However, citric acid content was found to be highest in R. lepida. The methanolic extracts of the three mushrooms exhibited high DPPH radical scavenging activities ranging from 74.92% to 58.92%. These wild edible mushrooms could be considered a potential supply source of adequate natural antioxidant for local population.

Lubricated squeezing flow experiments on wheat flour dough have been performed in constant plate speed and constant extension rate modes. The objective of this work was to assess the effects of the target values on the attained results obtained during wheat dough rheological properties measurement. Different rheometers were used to allow these operations. In both cases, each constant target speed used increases with the increasing time before reaching its stability. These increasing effects versus time are higher with greater speeds. It was obtained 20.1–41.5% of increasing time ratio between the two modes from the lower to higher speeds and for each given speed (0.005–1.5 [mm·s−1 or s−1]). The target speed increasing in order to reach the attained value caused sample dough deformation. These strain effects of dough are more important for high initial thickness of dough. Whatever the types of dough strain needed and target speed level used, the limit force measurable in many cases was 40 N (newton). It was a constrain factor for measured values. The data processing to obtain dough rheological properties remains too long and difficult with both measurement methods. Practical Applications In search of viable ways to study dough rheological properties, the uses of empirical and fundamental methods are of appropriate possibility. Several methods are further able to be used to measure and record dough rheological properties under conditions of unsteady flow. They are used to assess flour ability and provide dough with good breadmaking performance, to mimic dough stretching and to measure its resistance to rupture. Consequently, efficient and versatile methods have opened new possibilities for studying viscoelasticity behaviors related to cereals science and processing. These benefit effects make basic new methods used in breadmaking process, a powerful tool for monitoring the consistency and structural changes in dough and final bread. Because of their major importance in breadmaking process, it is essential in this study to assess the effects of the target values on the attained results in dough rheological properties measurement methods. They can help understand their implications on the data processing of these tests for reliable research on dough rheology.

The objective of this work was to study the effects of wheat flour dough’s viscoelastic level by adding glucose oxidase (Gox) on its rheological properties at dynamic shear strain mode to predict the final product quality. Dough does display a linear viscoelastic domain. Glucose oxidase (Gox) was added to dough in order to enhance its viscoelasticity and to take into account the possible effects of this viscoelasticity on the results. Whatever the types of dough strain used G’ increased, tan δ decreased and led to less sticky dough. Wheat flour dough, an increase in G’ with extension may be associated to a strain-hardening phenomenon but the role of dough viscoelasticity is discussed.

The effects of fruit maturity on oxidative stability of LSO were investigated using an accelerated test at 60C for 6 days. Fatty acid composition, Cox, PV, p-AV, specific extinction at 232 and 268 nm, and TOTOX were used to assess LSO stability. LSO samples from berry seeds at 50-DAFS, at CPW and at CPW + S60 were analyzed. LSO at CPW was significantly more stable to oxidation than LSO at 50-DAFS and CPW + S60.This oil had lower p-AV than control (peanut oil) and other sources of LSO. PV, specific extinction, TOTOX and Cox of LSO at CPW were also lower than thoseof 50-DAFSandCPW + S60,buttwotimeshigherthancontrolvalues.Collectively,these data suggest that LSO cannot be used after 3 days of storage at 60C.

Taro (Colocasia esculenta cv fouê) corm was subjected to different boiling times and the changes in chemical composition and physico-functional properties were investigated using standard method. The change in boiling time led to a significant (P

The activity of a crude enzyme preparation extracted from hepatopancreas in the digestive tract of the giant cricket Brachytrupes membranaceus (Drury) was assayed for amylase and α-glucosidase. Amylase- and α-glucosidase-specific activities were estimated to be 3.31 and 13.02 UI/mg, respectively. The zymogram analysis of the crude enzymatic extract showed the existence of two isoforms of amylase. For α-glucosidase, the zymogram analysis showed one form only. Both the amylolytic activities exhibited optimum pH at 6.6 and 7.0, respectively, for amylase and α-glucosidase. As for optimum temperature, values were estimated at 55 and 40 °C for amylase and α-glucosidase activities, respectively. Amylase activity was found to be stable at pH 6.6–7.6 and temperatures up to 55 °C. The corresponding values for α-glucosidase were pH 6–7 and up to 40 °C. Amylolytic enzymes of B. membranaceus were activated by Ca2+ and Ba2+ and inhibited by chemical agents such as ethylenediaminetetraacetic acid, 4-chloromercuribenzoic acid and dithionitrobenzoic acid. The analysis of hydrolytic products after soluble starch hydrolysis by the enzyme preparation from the digestive tract of B. membranaceus by thin layer chromatography revealed that glucose and maltose were the major products. The present study showed that these amylolytic enzymes play a fundamental role in energy production for this insect.

Polyphenol oxidase (PPO Y ) of edible yam (Dioscorea cayenensis-rotundata cv. Longbo) cultivated in Cote d'Ivoire was purified to homogeneity by a procedure that included ion exchange chromatography, ammonium sulphate fractionation, gel filtration and hydrophobic chromatography using dopamine as a substrate. The relative molecular weight of the PPO Y was estimated to be 94.75 ± 0.63 and 151.56 ± 2.75 kDa by SDS-PAGE and gel filtration on Sephacryl S100 HR, respectively, indicating this PPO Y as a multimer. Maximal PPO Y activity occurred at 30 °C and pH 6.6. The enzyme was stable at 25 °C and its pH stability was in the range of 6.0-7.0. The values V max /K m showed that the enzyme had the greatest reactivity towards dopamine among the substrates used. PPO Y showed no activity toward the monophenols and was completely inhibited by beta-mercaptoethanol, sodium thiosulphate, L -ascorbic acid, sodium bisulphite and L -cysteine. Data generated by this study might help to better prevent edible yam browning.

A beta-glucosidase was purified from the digestive fluid of the palm weevil Rhynchophorus palmarum L. (Coleoptera: Curculionidae) by chromatography on anion-exchange, gel filtration, and hydrophobic interaction columns. The preparation was shown to be homogeneous on polyacrylamide gels, beta-glucosidase is a monomeric protein with a molecular weight of 58 kDa based on its mobility in SDS-PAGE and 60 kDa based on gel filtration. Maximal beta-glucosidase activity occurred at 55 degrees C and pH 5.0. The purified beta-glucosidase was stable at 37 degrees C and its pH stability was in the range of 5.0-6.0. The enzyme readily hydrolyzed p-nitrophenyl-beta-D-glucoside, cellobiose, cellodextrins and required strictly beta-gluco configuration for activity. It cleaved glucose-glucose beta-(1-4) linkages better than beta-(1-2), beta-(1-3) and beta-(1-6) linkages. The catalytic efficiency (K(cat)/K(M)) values for p-nitrophenyl-beta-D-glucoside and cellobiose were respectively 240.48 mM(-1)s(-1) and 134.80 mM(-1)s(-1). Beta-glucosidase was capable of catalysing transglucosylation reactions. The yield of glucosylation of 2-phenylethanol (20 %), catalysed by the beta-glucosidase in the presence of cellobiose as glucosyl donor, is lower than those reported previously with conventional sources of beta-glucosidases. In addition, the optimum pH is different for the hydrolysis (pH 5.0) and transglucosylation reactions (pH 6.6).

A beta-galactosidase from the digestive juice of the palm weevil Rhynchophorus palmarum L. larvae was purified by chromatography on ion exchange, gel filtration, and hydrophobic interaction columns. The preparation was shown to be homogeneous on polyacrylamide gel. Beta-galactosidase was a monomeric protein with a molecular weight of 62 kDa based on its mobility in sodium dodecyl sulfate–polyacrylamide gel electrophoresis and 60 kDa based on gel filtration. Maximal enzyme activity occurred at 55°C and pH 5.0. The purified beta-galactosidase was stable at 37°C and its pH stability was in the range of 4.6–6.0. Beta-galactosidase was highly specific for the beta-d-galactosyl residue and beta-(1-4) linkage. The catalytic efficiency (Vmax/Km) values for p-nitrophenyl-beta-d-galactopyranoside, beta-d-galactosyl(1-4)-d-glucose (lactose), beta-d-galactosyl(1-4)-d-galactose and beta-d-galactosyl(1-4)-beta-d-galactosyl(1-4)-d-glucose were, respectively, 72.95, 10.97, 20.74 and 12.73. 5,5-Dithio-bis(2-nitrobenzoate) and sodium dodecyl sulfate inhibited completely the beta-galactosidase activity. The enzyme was capable of catalyzing transgalactosylation reactions. The yield of galactosylation of 2-phenylethanol (43%), catalyzed by the beta-galactosidase in the presence of lactose as galactosyl donor, is higher than those reported previously with conventional sources of beta-galactosidases. In addition, the optimum pH is different for the hydrolysis (pH 5.0) and transgalactosylation reactions (pH 6.0).

Cockroach Periplaneta Americana α-amylase hydrolysed starch to maltose and maltodextrin. However, this enzyme was not active against maltose and maltotriose (2 h of reaction). α-Glucosidase of the same organism exhibited activities toward maltose and maltodextrin to glucose. Synergism was observed especially between both enzymes to produce glucose for cockroach P. Americana nutrition. Key Words: α-Amylase, α-glucosidase, cockroach, Periplaneta Americana , synergism. African Journal of Biotechnology Vo l.3(10) 2004: 529-533

The aim of the study was to monitor variations of starch granules in two varieties of yam tuber parts during post-harvest storage. The morphological properties of yam part starches isolated from two cultivars ("Kangba" and "Krengle") belonging to Dioscorea cayenensis-rotundata complex species were evaluated. The shapes of starch granules from yam tuber parts of each cultivar were similar and these shapes were the same from one cultivar to another. They appeared polyhedral, ovo-triangular, oval and some oblong. As for the granulesf size, it appeared significant (P.0.05) and ranging from 5.8 ƒEm to 61.8 ƒEm in the proximal tuber parts and 5.4 ƒEm to 53.8 ƒEm in distal tuber parts during the post-harvest storage. The proximal tuber parts had the highest size of granules (O = 26.8-36.6 ƒEm). Moreover, the different tuber parts of "Kangba" cultivar presented the highest size of starch granules (O = 27.5-36.3 ƒEm).

The use of nitrophenyl derivatives in the determination of the influence of manganese ion on catalytic activities of glycosidases and phosphatases remains a problem. In fact, in this study, adding manganese chloride or manganese sulfate to sodium hydroxyde or sodium carbonate in aqueous solution yielded secondary reactions. These secondary reactions affected the absorbance for wavelengths varying between 400-420 nm. This chemical behavior did not allow reliable results in determining the influence of manganese ion on glycosidase and phosphatase activities, when nitrophenyl derivatives were used as substrates. This study showed that this problem could be avoided when natural substrates such as disaccharides (glycosidases) and phosphorylglycosides (phosphatases) were used in enzymatic tests.

Two biological fluids, namely hemolymph and digestive fluid from the larval stage of Rhynchophorus palmarum Linneaus, a serious pest in agroecosystem exploiting oil palm, were screened for hydrolytic activities, by the use of synthetic and natural glycoside substrates. Several exo and endoglycosidase activities were observed but, the interesting alpha-mannosidase activity (0.41 +/- 0.04 UI) had attracted our attention. So, we have previously demonstrated that this activity harbours four distinctive alpha-mannosidase isoforms named RpltM, RplM1, RplM2 and RplM3. We have extended this work to determine the ability of these enzymes to catalyze synthesis reactions. Finally, we have revealed that, alpha-mannosidases from the digestive fluid of R. palmarum larvae catalyze transmannosylation reactions. The stability of the enzymes and the optimization of the transfer product yield were studied as functions of pH, enzyme unit, starting concentration of donor or acceptor and time. It was shown that, in experimental optimum conditions, average yields of 12.34 +/- 0.75, 12.15 +/- 0.79, 5.59 +/- 0.35 and 8.43 +/- 0.50% were obtained for the alpha-mannosidases RpltM, RplM1, RplM2 and RplM3, respectively. On the basis of this work, alpha-mannosidases from the digestive fluid of Rhynchophorus palmarum larvae appear to be a valuable tool for the preparation of neoglycoconjugates.

L\'objectif de ce travail etait d\'utiliser la blatte Periplaneta americana comme source de glycosidases a activites originales pouvant intervenir dans la valorisation des molecules alimentaires et non alimentaires des ressources agricoles et comprendre la degradation des macromolecules alimentaires chez cette espece de blatte. Cette etude a ete realisee a l\'aide de l\'extrait brut enzymatique total et des differentes portions du tube digestif de la blatte Periplaneta americana. Il ressort de ce travail que l\'extrait brut enzymatique total de la blatte Periplaneta americana possede un equipement glycosidasique dont l\'action s\'exerce aussi bien sur les polyholosides, les heterosides que sur les oligosides. De facon generale, ces activites osidasiques obtenues a des pH optimums acides sont mesophiles avec des temperatures optimales comprises entre 45 et 60 °C dans le tampon acetate. Cependant, les activites &#945-galactosidasique, &#945-mannosidasique, &#945-glucosaminidasique et &#945- xylosidasique sont thermophiles. L\'etude de l\'inactivation thermique montre que certaines de ces activites sont stables (activites xylanasique, lichnanasique, amylasique, &#945-glucosidasique et invertasique). La comparaison des activites enzymatiques obtenues dans les differentes parties du tube digestif de la blatte Periplaneta americana montre que la majorite des enzymes etudiees sont surtout distribuees au niveau des intestins moyen (mesenteron) et anterieur et dans une moindre mesure au niveau de la panse. Ce qui nous fait penser que la degradation des macromolecules en sucres simples chez cette blatte a lieu principalement dans ces portions. Ces resultats montrent que la blatte Periplaneta americana possede une richesse en diverses glycosidases qui pourraient constituer apres purification des outils enzymatiques indispensables dans les industries agroalimentaire, pharmaceutique et du textile. Keywords : Blatte, Periplaneta americana, activites osidasiques, distribution, tube digestif. International Journal of Biological and Chemical Sciences Vol. 2 (2) 2008: pp. 128-138

Acid phosphatase activity was detected in peanut (Arachis hypogaea) cotyledons during germination. Four (4) to six (6) days of germination was the meantime corresponding to maximum hydrolytic activity of this enzyme. The understanding of the role of acid phosphatase activity during germination led to purify this enzyme by successive chromatography separations on DEAE-Sepharose CL-6B, Sephacryl S-100 HR and Phenyl-Sepharose HP to apparent homogeneity from germinated peanut cotyledon five days old. This enzyme designated peanut cotyledon acid phosphatase (AP) had native molecular weight of 24 kDa by gel permeation. SDS-PAGE of the purified acid phosphatase resolved a single protein band that migrated to approximately 21.5 kDa. Thus, this acid phosphatase likely functions as a monomer. The enzyme had optimum pH (5.0) and temperature (55 degrees C), and appeared to be stable in the presence of anionic, cationic and non-ionic detergents. Substrate specificity indicated that the purified acid phosphatase hydrolyzed a broad range of phosphorylated substrates. However, natural substrates such as ADP and ATP were the compounds with highest rate of hydrolysis for the enzyme. Moreover, the purified acid phosphatase exhibited phytase activity. These results showed that this enzyme played a peculiar role during germination, notably in reducing the rate of phytic acid, an antinutritional substance contained in peanut seed.

Termite workers, Macrotermes subhyalinus (Rambur), produced two cellulase-free xylanases, namely Xyl A and Xyl B. DEAE-Sepharose CL-6B, Sephacryl S-200 HR, CM-Sepharose CL-6B and Phenyl-Sepharose CL-4B chromatographies purified these enzymes. They exhibited molecular masses of 63–66.1 (Xyl A) and 60.7–62.4 (Xyl B) kDa. Both enzymes appeared to be endo-xylanases, which produced oligomers of xylose from xylan and did not hydrolyse them to xylose. They had different optimum pH (pH 4.6–5.0 for Xyl A and pH 5.0 for Xyl B) and different optimum temperatures (60 °C for Xyl A and 55 °C for Xyl B). However, they had the same pH stability (4.0–5.6). Both enzymes were stable at 50 °C for more than 4 h. At a pH ranging from 4.6–5.0 and 60 °C, Xyl A and Xyl B possessed the half-life of 115 and 60 min, respectively. The xylanase activities were stimulated by Na+, Mn2+ and dithiol-reducing agents and were sensitive to Cu2+ and detergent agents. Their enzymatic activity was slightly reduced by the presence of urea at 1% (w/v) concentration. The two enzymes could be used in the presence of organic solvents such as acetone (up to 10% v/v) without loss of activity.

Two s-glycosidases were purified from the termite Macrotermes subhyalinus (Rambur) workers by chromatography on gel filtration, ion exchange and hydrophobic interaction columns. The preparations were shown to be homogeneous on Polyacrylamide gel. Both enzymes have a similar molecular mass (68 KDa) and optimum pH (5.4) but differ in optimal temperature and thermal stability. The s-glycosidases preferred s-fucosides to s-glucosides, s-galactosides and s-xylosides, and hydrolysed glucose-glucose-s-(l-4) linkages better than s-(l-3), s-(l-2) and s-(l-6) linkages. They did not hydrolyse saccharides such as melibiose, sucrose, lactose, xylobiose, melizitose, stachyose, lactose, raffinose, laminarin, arabinogalactan, carboxymethylcellulose, inulin, lichenan and starch. s-Glycosidase A and s-glycosidase B of M. subhyalinus workers are capable of catalysing transglucosylation reactions. The yields of glucosylation of hydroxyamino acid derivatives and phenylethanol, catalysed by the two enzymes in the presence of cellobiose as glucosyl donor, were lower than those reported previously with conventional sources of s-glycosidases. In addition, the optimum pH is different for the hydrolysis and trans glucosylation reactions.On the basis of this work, it is proposed that the physiological role of s-glycosidase A and s-glycosidase B of M. subhyalinus workers is the digestion of di- and oligosaccharides derived from hemicelluloses and celluloses.