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Omemu, A. M., Edema, M. O.*, Atayese, A. O. and Obadina, A. O.
Abstract: The dried calyx of Hibiscus sabdariffa (Roselle) is locally processed into a non-alcoholic drink known as ‘Zobo’ in Nigeria. This popular drink is quite cheap compared to other bottled soft drinks but its acceptability is still limited because of its very short shelf life (24 h at room temperature). The composition and numbers of the microflora of the dried calyx of the Roselle plant and its resulting juice (Zobo) were examined using standard microbiological methods. The dried calyx obtained from a retail market was processed into juice that was compared with commercially sold (retail) juice. The microorganisms isolated from the dried calyx and the juices included the fungi, Aspergillus niger, Aspergillus flavus, Rhizopus oligosporus, Penicillium citrinum, Mucor spp., Saccharomyces cerevisiae, and Candida krusei, while Bacillus subtilis, Pseudomonas spp., Staphylococcus aureus, Streptococcus faecalis, Escherichia coli, Proteus mirabilis, Serratia spp., Lactobacillus brevis and Lactobacillus fermentum represented the bacterial isolates. Viable counts ranged from 0.4 x 104 to 3.2 x 104 cfu/ml. Aerobic and anaerobic bacterial counts were higher in the retail juice (1.1 to 2.2 x104 cfu/ml) than in the laboratory-prepared juice (0.8 to 1.4 x104 cfu/ml) while the dried calyx had the highest fungal counts of 3.2 x 104 cfu/ml. pH of the juices ranged between 2.67 and 2.77 while total titratable acidity values were between 0.02 and 0.08.[...] Read More.
Keywords: Dried calyx, microflora, viable counts, Zobo juice.
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文章
Y. Yahaya*, C.A. Echekwu and S.G. Mohammed
Abstract: Genotype x environment interaction in pearl millet [Pennisetum glaucum (L.) R.Br.] was studied for grain yield by growing 90 genotypes consisting of 81 hybrids and 9 inbred parents at 5 locations for 2 years. Genotype x environment interaction was observed, a large component of which was accounted for by non-linear regression on the environment means. Although the linear portion was significant, its magnitude was smaller than that of the non-linear component indicating the significance of environmental effects on the genotypes. Six hybrids were found to be stable across the environments. They yielded above the average mean yield of all the genotypes under test, with a slope of unity and the mean square due to deviation from regression equal to zero.[...] Read More.
Keywords: Genotype x environment interaction, yield, stability, pearl millet.
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文章
Ayman A. Diab
Abstract: In the past, it has been difficult to accurately determine the location of many types of barley molecular markers due to the lack of commonality between international barley linkage maps. In this study, a consensus map of barley was constructed from five different maps (OWB, VxHs, KxM, barley consensus 2 and barley consensus 2003) to produce the consensus AD-2005 map with 1536 markers. The QTL that have been identified in previous barley studies were then incorporated into the integrated consensus map to provide a quick method of aligning and comparing barley linkage maps and to identify markers closely linked to barley traits. The markers placed on this map are consistent with respect to order on the chromosomes with the individual maps and other barley maps with a few minor differences. The consensus AD-2005 was compared with rice Cornell RFLP map to examine the reliability of the constructed map in comparative genomic studies. Unlike previous consensus maps, the purpose of this consensus map (containing QTL) is to provide a tool for scientists to accurately locate molecular markers to chromosome regions responsible for economically important traits. It is estimated that markers placed on the consensus map are located very close to their true positions as determined by the five maps used in this study. It is envisaged that the consensus map will benefit small-grain researchers by providing an efficient means of choosing markers of interest and identifying QTL regions for future genetic or plant breeding studies on a worldwide basis.[...] Read More.
Keywords: Barley, QTL, genetic linkage mapping, consensus map, comparative genome mapping.
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Padmalatha K, Prasad M.N.V*
Abstract: Genetic analysis of plants relies on high yields of pure DNA samples. Here we present the optimization of DNA isolation and PCR conditions for RAPD analysis of selected medicinal and aromatic plants of conservation concern from Peninsular India containing high levels of polysaccharides, polyphenols and secondary metabolites. The method involves a modified CTAB extraction employing polyvinyl pyrrolidone while grinding, successive long-term Chloroform : lsoamyalcohol extractions, an overnight RNase treatment with all steps carried out at room temperature. The yield of DNA ranged from 1-2 µg/µl per gram of the leaf tissue and the purity (ratio) was between 1.6-1.7 indicating minimal levels of contaminating metabolites. The technique is ideal for isolation of DNA from different plant species and the DNA isolated was used for randomly amplified polymorphic DNA (RAPD) analysis. RAPD protocol was optimized based on the use of higher concentration of MgCl2 (3 mM), lower concentrations of primer (0.5 µM) and TAQ polymerase (0.2 units), 50 ng of template DNA and an annealing temperature of 37°C, resulted optimal amplification. Reproducible amplifiable products were observed in all PCR reactions. Thus the results indicate that the optimized protocol for DNA isolation and PCR was amenable to plant species belonging to different genera which is suitable for further work on diversity analysis.[...] Read More.
Keywords: Vitex pubescens, Nervilia aragoana, Gymnema sylvestre, Withania somnifera, Origanum majorana, Boswellia serrata, Saraca asoca, Gloriosa superba, polysaccharides, PCR amplification.
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A. A. Bakare *, M. A. Azeez and J. O. Agbolade
Abstract: The distribution and gene frequencies of ABO and rhesus (Rh) blood groups and haemoglobin variants for samples of the Nigerian population at Ogbomoso was determined. Data consisting of records of blood groups and haemoglobin types of different ages ranging from infants to adults for a period of 4 to 6 years (1995 – 2000) was collected from Baptist Medical Centre (BMC), Ladoke Akintola University of Technology Health Centre (LAUTHC) and Oyo State General Hospital (OSGH), all in Ogbomoso, Oyo State, Nigeria. Overall, a total number of 7653, 7053 and 14,845 individuals were typed for ABO and Rh blood groups, and haemoglobin genotypes, respectively. 3824 (50%) were blood group O, 1750 (22.9%) were blood group A, 1629 (21.3%) were blood group B and 450 (5.9%) were blood group AB. This distribution differs significantly (P AS (21.0%) > AC (5.7%) >SS (3.0%) >SC (2.0%) >CC (0.3%). The gene frequencies were 0.81, 0.14 and 0.04 for A, S and C alleles, respectively. Our results are representative of the distribution of these genetic variants in Nigeria.[...] Read More.
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G. N. Ude,*, C.O. Dimkpa, P. O. Anegbeh, A. A. Shaibu, A. Tenkouano, M. Pillay and Z. Tchoundjeu
Abstract: Amplified fragment length polymorphism (AFLP) was used to assess genetic diversity and relationships among 15 accessions of Irvingia gabonensis collected from Cameroun, Gabon, and Nigeria. Twelve AFLP+3 primers produced 384 polymorphic fragments. Average genetic distance (AGD) between the 15 accessions was 58.7% (32-88%). AGD and range of genetic distance among accessions from Cameroun, Nigeria and Gabon were 62% (53-76%), 52% (32.3 – 84.8%) and 50% (45-53%), respectively, indicating more genetic diversity in Cameroun than Nigeria and Gabon. The unweighted pair-group method of the arithmetic average (UPGMA) and principal coordinate analysis (PCO) showed a clear distinction between the Gabon and Nigeria accessions into two separate clusters, with accessions from Cameroun overlapping them. Principal coordinate analysis (PCO) indicated a closer relationship between accessions from Cameroun and Gabon. In general the Cameroun germplasm appears to be a bridge between the genetically isolated Nigeria and Gabon accessions. This overlap of Gabon and Nigerian accessions by the accessions from Cameroun may be an indication that Cameroun is the center of diversity of I. gabonensis and also the primary source of original materials grown in the other countries. More collection in Cameroun is necessary to ensure the optimum collection and preservation of the existing genetic diversity in I. gabonensis.[...] Read More.
Keywords: Irvingia gabonensis, Accession, amplified fragment length polymorphism, genetic diversity.
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Chunxia Wang and Yongquan Li*
Abstract: Theaflavins is a group of very important material from black tea with functions as antioxidant, cancer suppressor and inhibitor of pathogenic microorgnisms. A discription is given on the property, chemical structure and application of theaflavin in this paper. The present research situation of theaflavins both in China and abroad is also reviewed.[...] Read More.
Keywords: Theaflavins, property, application.
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文章
Mtebe Kaswija, Mamiro Peter*, Fweja Leonard
Abstract: The need to develop the best off vine mango ripening technique for both consumption and processing was investigated. Sensory quality and microbial contamination was studied on mature green Dodo mangoes before and during a 3- and 6-day ripening period by Smoked Pit Ripening (SPR), Ethylene (fruit generated) Pit Ripening (EPR), Untreated Pit Ripening (UPR) and Room Temperature Ripening (RTR) as a control method. The post harvest ripening changes in the quality characteristic of ripe mangoes were correlated among treatments and compared with similar changes in other mango varieties. The results showed insignificant differences in sensory attributes among the employed techniques. Microbial quality was significantly different within the treatments, while with aroma profiles there were considerable differences of detected aromatic compounds between raw and ripe mango fruits. Increased number of aromatic compounds reflected the most significant sensory scores at ripening stage.[...] Read More.
Keywords: Mango, microbial quality, flavour, ripening, aroma.
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文章
Ashraf A. Khalil
Abstract: Germination and/or fermentation processes for Egyptian breeds of mung seeds were carried out with three Lactobacillus strains namely, L. reuteri, L. case, and L. heleviticus. Results revealed increase in protein content, nitrogen solubility and in vitro digestibility for all treated mung meals. Treated mung proteins contained most of the essential amino acids in concentrations comparable to those recommended by the FAO/WHO, with the exception of the sulphur-containing amino acids. Trypsin inhibitor units (TIU) and phytate content of untreated MB were 6.98 TIU/mg dry sample and 5.61 mg phytate/g dry sample, respectively. Fermentation treatments were effective in decreasing the phytate content as well as reducing trypsin inhibitor activity, while L. casei was the most efficient probiotic culture in reducing those antinutritional factors. The combined treatment of germination and lactic fermentation utilizing Lactobacillus species is recommended process for enhancing the nutritional quality of legume protein.[...] Read More.
Keywords: Mung bean, protein extract, Lactobacillus, fermentation, germination, nutritive value.
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文章
Sk Masud Hossain* and N. Anantharaman
Abstract: Suspended cultures of white-rot fungus, Trametes versicolor, supplemented with bagasse powder showed a concentration dependent enhancement in the ligninolytic enzymes activity in liquid shake cultures. 2% (w/v) bagasse powder improved greater stability to the enzymes. The optimum pH is 3.5 and the optimum temperature is 40°C for maximum lignonolytic enzymatic activity. The optimum shaking speed is 60 rpm for maximum enzymatic activity. The maximum enzymatic activity showed by T. versicolor is 495, 440 and 410 mmol/ml.min for LiP, MnP and laccase with bagasse powder at optimum conditions, respectively. Without bagasse powder at optimum conditions, the maximum enzymatic activity for LiP, MnP and laccase is 195, 150 and 170 mmol/ml.min, respectively.[...] Read More.
Keywords: Bagasse, enhancement, enzymes, optimum, white-rot fungus.
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