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Studies on Low-cost Substrates and Other Cultural Conditions for Optimal Amylase Yield from Aspergillus oryzae-SR2
U.O. George-Okafor,F.O. Tasie,N.C. Anyamene
American Journal of Food Technology , 2013,
Abstract: The need for starch-converting enzymes in various industries has led to enormous interest in their production at a cheap rate. The present study was focused on the examination of various inexpensive substrates and other production parameters for amylase production by the most potential selected strain. It was observed that A. oryzae-SR2 was the best amylase producer (36.31±0.24 mm) among other Aspergillus isolates when screened by starch hydrolysis test. Preliminary submerged fermentation using soluble starch medium confirmed the potentials of A. oryzae-SR2 for amylase production. The maximum enzyme production under submerged fermentation was achieved with 0.5% sugar-cane juice supplemented with 0.5% dry-flakes fermented tapioca, 1% yeast extract, 7% inoculums concentration, pH 7.0, temperature of 55°C and incubation period of 48 h. The enzyme demonstrated strong hydrolytic activities (56.4%) on the tested starchy foods with cassava starch being the most hydrolyzed (101.5%) with 86.90±1.10% conversion efficiency at 70°C. The ability to produce high amount of amylase within a relatively short time (48 h) using cheap substrates and the ability of its enzyme to effectively hydrolyze starchy foods suggests its suitability for biotechnological application especially in starch-converting industries.
Purification and Some Properties of Thermo-stable Alkaline Serine Protease from Thermophilic Bacillus sp. Gs-3
U.O. George-Okafor,F.J.C. Odibo
Journal of Biological Sciences , 2011,
Abstract: There are limited reliable information on the commercial production and utilization of proteases for detergent and other industrial uses in Nigeria. Hence, the purification and characterization of Bacillus sp. Gs-3 protease for its potential industrial uses were investigated. The dialyzed crude enzyme was purified 17-fold in a two-step procedure involving carboxymethyl sepharose ionic-exchange chromatography and phenyl sepharose 6-fast flow hydrophobic interaction chromatography. The purified enzyme had its optimal activity at pH 9.0 and 90C and was stable over a pH range 8.0-11.0. It readily hydrolyzed all the tested protein substrates but exhibited highest affinity for gelatin (Km 0.15 mg mL-1). It retained at least 66.20.02% of its original activity in the presence of the tested local commercial detergents and removed bloodstains completely. Its activity was significantly (p>0.05) enhanced by Cu2+ ion but strongly inhibited (75.60.07%) by Phenyl-methyl Sulfonyl Fluoride (PMSF). Thus, the enzyme demonstrated desirable properties suitable for its biotechnological applications especially in detergent industry.
The Potentials of Lime (Citrus aurantifolia) for Improving Traditional Corn Fermentation for Probiotic Lactic Acid Bacterial Proliferation
Uzoamaka Ogechi George-Okafor,Enuma Ekpereka Anosike
Pakistan Journal of Nutrition , 2010,
Abstract: Lactic Acid Bacteria (LAB) as probiotic organisms can be sourced from fermented diary and vegetable products. The problem in Nigeria is their affordability to the greater populace, as the common sources are relatively expensive. The study was aimed at sourcing for a low cost meal rich in probiotic LAB by utilizing raw lime juice for the fermentation of corn. Washed yellow corn variety (6%) was fermented using prepared lime solution (pH 5.1-5.5). The lime-fermented corn was wet-milled, sieved and the resulting substrate was enumerated for LAB and coliform on DeMan Rogosa Sharpe’ agar and MacConkey agar plates respectively. The predominant LAB were characterized as Lactobacillus fermentum, Lactobacillus plantarum and Lactobacillus acidophilus. At their predetermined optima growth periods (18 h, 22 h and 24 h), they were evaluated for antimicrobial potentials against Salmonella typhi, Shigella dysenteriae and Candida albicans. Their resistance to acid, bile and antibiotics was determined. The LAB (>3.80 x 108±012 cfu/ml) recovered from lime-treated samples were significantly (p<0.05) higher than that from untreated samples (<5.70 x 106±003 cfu/ml). The pH (<5.3) and coliform counts (<0.50 x 101±013) were also reduced in the treated sample. Although their antibiotic resistance was very low, the test LAB especially L. acidophilus demonstrated efficient probiotic properties by inhibiting the test pathogens, maintaining >78% acid stability at pH 3 and withstanding up to 20% bile concentration at 51.4% survival rate. These results reveal that low cost lime-fermented corn is a rich source for probiotic LAB and thus can be recommended as a food supplement.
COCOA PRODUCTION - AGRICULTURAL CREDIT GUARANTEE SCHEME FUND NEXUS IN NIGERIA: A COINTEGRATION APPROACH
O. Oyakhilomen,U.O. Omadachi,R.G. Zibah
Russian Journal of Agricultural and Socio-Economic Sciences , 2012,
Abstract: This study was carried out to examine the relationship between cocoa production in Nigeria and agricultural credit guarantee scheme fund using time series data on cocoa production in Nigeria, value of loans guaranteed and number of loans guaranteed spanning over the period of 1981 to 2011. The Johansen cointegration test was employed in this study and the result indicated that there was no cointegrating relationship between cocoa production in Nigeria and Agricultural credit guarantee scheme fund over the period under study. This could be attributed to the guaranteeing of few number as well as limited value of credit to the farmers by agricultural credit guarantee scheme fund and the high incidence of loan diversion by the cocoa farmers who had access to the loans guaranteed by agricultural credit guarantee scheme fund. It is recommended that the number as well as the value of credit guaranteed to cocoa farmers should be significantly increased so as to enable the farmers expand their production and thereby, reposition the cocoa to assume a critical role as a major non-oil foreign exchange earner in the Agricultural transformation plan of Nigeria.
Satura？？o de manga (Mangifera indica L.) var. rosa com a？úcares
RIBEIRO, Margarida Sabino;SABAA-SRUR, Armando U.O.;
Ciência e Tecnologia de Alimentos , 1999, DOI: 10.1590/S0101-20611999000100021
Abstract: mango (mangifera indica l) cv. rosa was in a stage of initial physiological maturation, it was washed in solution that showed 8-10 ppm of free residue chlorine 0,1% of the neutral detergents and the ph adjusted and maintained at 6. the mango was peeled and cutted in cubes (2cmx2cm), treated in hot water in 85oc for about 10 minutes. after cooling off in freezer water, the cubes were immersed in syrup to 30 brix (90% saccharose + 10% glucose) and the ph was adjusted to 4. after 48 hours, it was reached the osmotic equilibrium, the syrup was drained and termic treatmented, and it was corrected with saccharose to the concentration of sugars in 10 brix. the each osmotic equilibrium of the syrup was increased in 10o brix and in the end of the process, the cubos had 71,6 and the syrup 76,5o brix. in beginning of the process, the ph was reduced but the acidez increased, likely of fermentation occured. at the end of the fermentation, the ph was between 3,8 to 3,9 and the reducing sugar concentration in cubos was 2,15% with increse constant. the final product demonstrated satisfatories qualities, keeping its characteristic taste, good consistency, uniform color, pleasant odor to use of the industrial products, like: cakes, candies, sweets, icecreams, etc.
Influence of Level and Duration of Quantitative Feed Restriction on Post-Restriction Egg-Laying Characteristics and Egg Quality of Pullets
S.N. Ukachukwu,U.O. Akpan
International Journal of Poultry Science , 2007,
Abstract: The effects of levels and duration of quantitative feed restriction on post-restriction egg-laying characteristics and egg quality as well as economics of egg production of pullets were investigated in a 2x7 factorial for completely randomized design experiment using 126 point-of-lay (POL) Olympia Brown commercial pullets, which had been subjected to various levels and durations of feed restrictions. The experiment lasted from 20th to 37th week of age but the actual period of data collection was from 30th to 37th week of age (that is, 8 weeks). The feeding regimens (treatments) were AFAF (ad libitum feeding from 20th week to 34th week - 14 weeks); AFRF1 (ad libitum feeding from 20th to 24th week (POL) – 5 weeks followed by 10% restriction feeding from POL to 34th week - 9 weeks); AFRF2 (ad libitum feeding from 20th to POL – 5 weeks followed by 20% restriction feeding from POL to 34th week - 9 weeks); RF1RF1 (10% restriction feeding from 20th to 34th week - 14 weeks); RF1AF (10% restriction feeding from 20th week to POL – 5 weeks followed by ad libitum feeding from POL to 34th week - 9 weeks); RF2RF2 (20% restriction feeding from 20th to 34th week - 14 weeks); and RF2AF (20% restriction feeding from 20th week to POL – 5 weeks followed by ad libitum feeding from POL to 34th week - 9 weeks). From 34th to 37th week of age, all the groups were reverted, on treatment basis, to ad libitum feeding (post-restriction period). Each treatment was replicated into three with six pullets per replicate. During the data collection period (30th – 37th week of age) one egg per replicate was collected three times per week for egg quality indices. Birds that were under feed restriction laid heavier first eggs but had lower (P<0.05) hen day production (HDP) than their ad libitum counterparts. Ad libitum fed birds transferred to 20% restricted feeding had the best economic indices. Birds subjected to restriction feeding had higher feed intake, poorer kg feed/dozen eggs, higher cost for dozen eggs (N) and lower gross margin (N) during post-restriction time (P<0.05) than when they were under restriction. On egg quality, birds had higher (P<0.05) haugh unit and albumen height but lower yolk index during restriction time than during post-restriction time. There were no significant differences in all the other quality indices
Satura o de manga (Mangifera indica L.) var. rosa com a úcares
RIBEIRO Margarida Sabino,SABAA-SRUR Armando U.O.
Ciência e Tecnologia de Alimentos , 1999,
Abstract: Mangas (Mangifera indica L.) var. Rosa, no estádio "de vez", selecionadas e lavadas em água contendo 8-10ppm cloro residual livre, 0,1% de detergente neutro e o pH ajustado e mantindo em 6, foram descascadas, cortadas em forma de cubos (2cmx2cm) e estes tratados em água a 85° C por 10 minutos. Após resfriados em água gelada, ficaram imersos em xarope a 30° Brix (90% de sacarose e 10% de glicose), sendo o pH ajustado para 4. Após 48 horas, o equilíbrio osmótico foi atingido, o xarope drenado, tratado termicamente, e a concentra o de a úcar aumentada em 10° Brix. A cada equilíbrio, o teor de a úcar era acrescido em 10° Brix e no final do processo, os cubos atingiram 71,6 e o xarope 76,5° Brix. No início do processo, o pH decresceu, enquanto a acidez aumentou em fun o da autofermenta o ocorrida no sistema. Cessado o processo fermentativo, o pH caminhou para o equílibrio, oscilando entre 3,8 a 3,9. O teor de a úcares redutores (AR) na fruta, que era de 2,15% no início do processo, esteve em contínuo aumento, em fun o dos tratamentos térmicos e do processo fermentativo, que contribuíram para que ocorresse a invers o da sacarose. No final do processso, esse teor era de 8,28%, que n o foi acompanhado pelo xarope, que apresentou 5,14% de AR, devido à redu o na velocidade de invers o da sacarose, ocasionada pela alta concentra o de sólidos solúveis, pelo grau de absor o de AR da fruta e pelo pH do sistema. Testes de aceitabilidade revelaram que 73% dos adultos e 76% das crian as consumiriam a manga critalizada.
Evaluación socioecónomica de la producción de goma de brea en el Chaco árido
von Müller,Axel R.; Coirini,R. O.; Karlin,U.O.;
Multequina , 2007,
Abstract: in argentina there is no productive development of the non wood forestry products (nwfp), so it is difficult to include them in the regional economies. as an example, brea gum from parkinsonia praecox produces an exudate gum as a food additive and safety to use in human consumption. however, it is not known, which is the economical feasibility for the farmers. the aim of this study is to evaluate the socioeconomical aspects of the brea gum production in the arid chaco from córdoba, argentina. the methodological approach for this study includes socio-economical surveys, gum production and finally, labour costs. data were analyzed using benefit/cost analyses for the different woodland degradation states. the economical feasibility of brea gum production includes chaco woodland in good state or "monte" and "breal". additionally, it is possible to include brea gum production within the producer of the social agrarian types with coger incomes, which economies depends mostly on external work. the production of brea gum makes a substantial contribution into farmers' incomes, giving more sustainability to the system.
THE PROSPECTS OF E-EXAMINATION IMPLEMENTATION IN NIGERIA
Ayo C. K.,Akinyemi I.O.,Adebiyi A.A.,Ekong U.O.
The Turkish Online Journal of Distance Education , 2007,
Abstract: ABSTRACTThe massive examination leakages, demand for gratification by teachers, bribe-taking by supervisors and invigilators of examinations have become a global phenomenon. This menace has resulted to general fallen standards of education and Nigeria is no exception, particularly among developing nations. Consequent upon this, all Nigerian universities have resorted to conducting post-entrance “Post-JAMB” examination/screening because of lack of confidence in the conduct of the entrance examinations. This paper proposes a model for e-Examination in Nigeria where all applicants are subjected to online entrance examination as a way of curbing the irregularities as proposed by the Joint Admissions Matriculation Board (JAMB), the body saddled with the responsibility of conducting entrance examinations into all the Nigerian universities. This model was designed and tested in Covenant University, one of the private universities in Nigeria. There were 120 questions drawn from English (30), Mathematics (30), General Science (20), Commercial Courses (20), and Religion Knowledge (20), all for one hour duration. Questionnaires were administered to the applicants at the end of the examination to assess their level of ICT literacy, ease of use of the system and the difficulties encountered.Findings revealed that the system has the potentials to eliminate some of the problems that are associated with the traditional methods of examination such as impersonation and other forms of examination malpractices. The system is easy to use and candidates can get use to it with time. The timing of examination can be spaced without compromising the quality and integrity of the examination. However, much is still desired if the system were to be adopted on a national scale, particularly in terms of infrastructural and manpower development. Similarly, the quest for e-Examination can fast track the development of e-Learning facilities in the country with improved access to education. Akinyemi I.O.Department of Computer and Information Sciences, Covenant University, Ota, Nigeria Adebiyi A.A.Department of Computer and Information Sciences, Covenant University, Ota, NIGERIA Ekong U.O.Department of Computer and Information Sciences, Covenant University, Ota, NIGERIAABSTRACTThe massive examination leakages, demand for gratification by teachers, bribe-taking by supervisors and invigilators of examinations have become a global phenomenon. This menace has resulted to general fallen standards of education and Nigeria is no exception, particularly among developing nations. Consequent upon th
Exclusive breastfeeding - the relationship between maternal perception and practice
U.O Uchendu, A.N Ikefuna, I.J Emodi
Nigerian Journal of Clinical Practice , 2009,
Abstract: The behaviour adopted by individuals is moulded by their perception of various issues. In spite of well established benefits of exclusive breastfeeding (EBF) to babies, mothers and society, the EBF practice rate (EBFPr) in our environment has remained low. To evaluatemother's perception of exclusive breastfeeding and determine the relationship between such viewand their practices. Two hundred mothers were interviewed to elicit their perception of the merit and demerits of exclusive breastfeeding.The pattern of perceptionwas related to actual practice in order to seek for possible associations. Of the 184 respondents, 39 (21.2%) practiced EBF for all their babies, while 95 (51.6%) never did so for any of their babies. Knowledge of EBF was excellent (94.0% and 90.8%) of the study group gave accurate definition and duration respectively. Most mothers felt that EBF babies look healthier (85.1%), have less disease (84.5%), are more intelligent (59.1%) but their mothers eat a lot (79.3%). Those who agree to the positive benefits of EBF generally had higher overall complete EBFPr than those who disagreed, as they looked healthier (p = 0.0001), had less disease (p = 0.041) andmore intelligent (p= 0.0001). In addition to this, mothers who did EBF for all babies ( ie those with an EBFPr of 100%) had more positive perception on the benefits ofEBF. There is a fairly good relationship between pattern of maternal perception of the benefits of EBF and actual practice. Efforts need to be intensified to educate and encourage mothers to see the merits of EBF both for themselves and their babies.
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