Open Access Original Research Article

Sequential Application of Plastic Media-Trickling Filter and Sand Filter for Domestic Wastewater Treatment at Low Temperature Condition

Abdul Rehman, Iffat Naz, Zia Ullah Khan, Muhammad Rafiq, Naeem Ali, Safia Ahmad

Biotechnology Journal International, Page 179-191
DOI: 10.9734/BBJ/2012/2013

Present research was aimed towards designing and construction of efficient plastic media-trickling filter (TF) for the treatment of domestic wastewater. The hydraulic flow rate through the TF was maintained at 80±2 ml/min at a temperature range of 5-15ºC by selecting treatment time of 12, 24, 36 and 48 hrs. Parameters like COD, BOD5, TSS, turbidity, NO3, NO2, SO4, PO4 and pathogenic indicator microbes were monitored after treatment of 12, 24, 36 and 48 hrs. The efficiency of the TF was improved with increase of time from 12 to 48 hrs. Maximum efficiency of TF was observed after 48 hrs treatment viz. 93.45, 93, 86.25, 57.8, 63.15, 25, 32.43, 99.95 and 86.3% reduction from the zero time value for BOD5, COD, TSS, PO4, SO4, NO3, NO2, turbidity and fecal coliforms respectively. Finally 48 hrs treated sample was passed through sand filter (SF) for further final polishing and approximately, 95.72, 95, 100, 73.5, 65.8, 58.3, 37.83, 100 and 91.5% reduction in BOD5, COD, TSS, PO4, SO4, NO3, NO2, turbidity and fecal coliforms was observed. This study showed that plastic media-trickling filter along with sand filter is a promising technology for wastewater treatment and can be scaled up for small communities in the developing countries.

Open Access Original Research Article

Neuroprotective Effect of Convolvulus pluricaulis Methanol Extract on Hydrogen Peroxide Induced Oxidative Stress in Human IMR32 Neuroblastoma Cell Line

Kshitija Dhuna, Vikram Dhuna, Gaurav Bhatia, Jatinder Singh, Sukhdev Singh Kamboj

Biotechnology Journal International, Page 192-210
DOI: 10.9734/BBJ/2012/1655

Aims: The present study aimed to evaluate and ascertain the protective role of methanolic/ethanolic/water extracts of Convolvulus pluricaulis against H2O2 induced cytotoxicity in IMR32 Neuroblastoma cell line as model system and identify the factor responsible for the protective effect.

Study Design:  Experimental study.

Place and Duration of Study: Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar & Department of Biotechnology, DAV College, Amritsar, PuCPab, between August 2010 and March 2012.

Methodology: Firstly, cytotoxic dose of H2O2 ­and non-toxic dose of methanolic, ethanolic and water extracts of C. pluricaulis (CP-MEx, CP-EEx and CP-WEx respectively) was determined by MTT assay. Protective effect of CP-MEx, CP-EEx and CP-WEx was determined using quercetin as a positive control. The expression of IMR32 cytoskeletal marker, Neurofilament (NF-200) and stress markers, Heat shock protein (HSP70) and (glucose regulated protein 75, Grp75) Mortalin studied by immunofluorescence and RT-PCR results. The level of antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase, direct scavenger of free radicals, Glutathione and lipid peroxidation were analysed by their standard procedures.

Results: The results showed that quercetin, CP-MEx, CP-EEx and CP-WEx displayed cytoprotective activity in IMR32 cells. Out of tested extracts CP-MEx significantly decreased hydrogen peroxide-induced cell death. Significant decrease in NF-200, HSP70 and Mortalin expression was observed in CP-MEx+H2O2 treated cultures as compared to H2O2 treated. Catalase, superoxide dismutase, glutathione peroxidase, Glutathione levels significantly increased in Quercetin and CP-MEx treated cultures. Lipid peroxidation was significantly decreased in both Quercetin and CP-MEx treated cultures.

Conclusions: The present work establishes the protective effect of CP-MEx on IMR 32 Human Neuroblastoma cell line which is as much as by quercetin. The cytoprotective effect of CP-MEx was due to induction of antioxidant machinery of the cell hence holds therapeutic value in the treatment and/or prevention of neurodegenerative disorders of oxidative stress.

Open Access Original Research Article

Ranking Rice (Oryza sativa L.) Genotypes Using Multi-Criteria Decision Making, Correlation and Path Coefficient Analysis

Khalid A. Mohamed, Atif Elsadig Idris, Hassan Ibrahim Mohammed, Khalid Abdalla Osman Adam

Biotechnology Journal International, Page 211-228
DOI: 10.9734/BBJ/2012/1821

The evaluation of selection criteria using correlation coefficients, multiple regression and path analysis was carried out for a period of two years on sixteen genotypes of rice (Oryza sativa L.).These genotypes were studied during 2008 and 2009 summer seasons at EDduim and Kosti locations in randomized complete block design with three replications per each location. The field experiment is directed to study character association; contribution of various yield influencing traits on rice for establishment of appropriate plant attributes to select and improve the grain yield, and accordingly select the most suitable genotype.

Combined analysis of variance revealed highly significant effects of locations, seasons, genotypes and their interactions for most of the studied traits indicating that these genotypes are highly variable. Genotypes differed significantly in grain yield, (NERICA 4, NERICA 14, NERICA 15, YUNLU 33 and WAB-1-38-19-14-P2-HB) were higher yielding genotypes giving 3.78, 4.03, 3.24, 3.55 and 3.51 t/ha respectively.  These genotypes presented a valuable source of diversity which can be used for breeding programs.

Correlation analysis in both seasons indicated that grain yield was positively and significantly correlated with plant height, number filled grains/ panicle and 1000-grain weight, while it was negatively correlated with percentage of unfilled grains/panicle. Path coefficient analysis indicated that among yield components number of filled grains/ panicle, number of panicles/m2 and 1000-grain weight showed a positive direct effect on grain yield and therefore, may be considered as selection criteria for the improvement of grain yield.

Multi-objective decision-making model was employed to rank the studied genotypes according to the measured various yield influencing traits and the degree of association of each trait on yield. For determination of criteria weight this article considers the analysis of correlation that is used frequently in to quantify the degree of association between a response variable, and some explanatory variable. Consequently, we propose new weighted information criteria to be used to guide the selection of the “best” genotype based on determining correlation coefficient. As a result, compromise programming analysis is in agreement with analysis of variance and indicated that genotypes can be ranked in a descending order as: N12, N14, Y30, WAB8, WAB19, N4, Y33, Y26, N15, N17 and Y24.

Open Access Original Research Article

Identification of Putative Vibrio Species Isolated from Processed Marine Fish Using Thiosulphate-Citrate-Bile-Sucrose (TCBS) Agar

Martha NNN Shikongo-Nambabi, Percy M. Chimwamurombe, Stephanus N. Venter

Biotechnology Journal International, Page 229-246
DOI: 10.9734/BBJ/2012/1507

Aims: To identify putative Vibrio isolates obtained from processed hake, pilchards and horse mackerel using Thiosulphate-Citrate-Bile-Sucrose (TCBS) agar.

Place and Duration of Study: Sampling during April – June 2005 in Walvis Bay Namibia. Further analyses performed at the Department of Microbiology and Plant Pathology, University of Pretoria, South Africa between 2005 and 2007.

Methodology: The 247 putative Vibrio isolates obtained from Thiosulphate-Citrate-Bile-Sucrose (TCBS) agar were initially grouped according to their Gram, oxidase and oxidation-fermentation reactions. Thereafter PCR was used to screen the isolates for genes specific to human pathogenic Vibrio species such as Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus. This was followed by sequencing the 16S rRNA gene for isolates of interest and drawing Neighbour Joining phylogenetic trees based on the data.  All atypical isolates were further characterised by a combination of selected phenotypic tests and the V. alginolyticus specific collagenase gene PCR. 

Results: Of the 247 isolates obtained from TCBS, four were Gram positive. Many of the Gram negative isolates belonged to the family Enterobacteriaceae and others were members of the Pseudomonadaceae. Of the 91 isolates identified as belonging to the Vibrionaceae and related families, Vibrio alginolyticus was the dominant Vibrio species. None of the bacteria isolated from the processed fish belonged to the human pathogenic Vibrio species.

Conclusion: This study again demonstrated that TCBS agar is not selective for the isolation of Vibrio species and that a wide range of bacteria could be isolated on this medium when analysing marine fish. The identity of putative Vibrio isolates obtained from this medium should therefore be confirmed employing a number of phenotypic and genetic techniques to accurately identify the atypical isolates.

Open Access Original Research Article

Hematological Changes of the African Catfish Clarias gariepinus (Burchell, 1822) Juveniles Induced by Diuron

F. Ajani, A. A. Awogbade

Biotechnology Journal International, Page 247-256
DOI: 10.9734/BBJ/2012/2119

Aim: To study the changes in haematological and plasma biochemical parameters of diuron at different sub-lethal levels on Clarias gariepinus juvenile.

Place and Duration of Study: Department of Animal Science and Fisheries Management laboratory, Bowen University, lwo, Osun State, between October 2010 to April 2011.

Methodology: The acute and chronic toxicity of various concentrations of Diuron on C. gariepinus juveniles was evaluated. Blood samples were taken after 14 and 28 days for the haematological and plasma biochemical analysis respectively.

Results: 96hr LC50 value of a working dilution of Diuron (0.03g/l) was obtained. The highest value of PCV and Hb was obtained in fish exposed to 1/10LC50 Diuron. At higher concentration (1/2LC50), significant decreases were observed in total protein and albumin. Fish exposed to a working dilution of 1/10LC50 (0.003g/l) in this study showed no significant difference to the control.

Conclusion: Diuron, a substituted urea, could be toxic at high concentration; therefore, further studies are required to evaluate the potential environmental risk of Diuron.

Open Access Original Research Article

Effects of Starch Fermentation on the Shelf-Life of Cassava Starch Based Adhesive

K. M. Oghenejoboh

Biotechnology Journal International, Page 257-268
DOI: 10.9734/BBJ/2012/2308

The effects of natural fermentation on the stability or shelf life of adhesives produced from starch of two cassava varieties (Manihot utilissima and Manihot palmate) were studied. It was observed that the HCN content of the Manihot utilissima reduced from 35.74±0.11 mg/kg for unfermented starch sample to 6.93±0.25 mg/kg after 5 days of fermentation (p = 0.037), while the sample’s pH increased from 4.60±0.05 to 6.89±00 respectively. However, the reduction in HCN concentration and corresponding increase in pH for manihot palmate were only marginal, as the concentration of HCN in the starch reduced from 2.49±0.12 to 0.89±0.26 while the pH increased from 6.02±0.04 to 6.35±0.05 after five days of fermentation. The viscosity test conducted at room temperature for a period of 30 days to determine the stability or shelf of the produced adhesives show that adhesives produced from unfermented Manihot utilissima starch sample as well as samples of that cassava variety fermented for only 1 day have longer shelf-life as exemplified by the relative stable low viscosity of the adhesive over the 30 days test period with a highly significant effect, (p = 0.018). The drying time of Manihot utilissima was significantly high at 7.1±0.01 minutes (p = 0.041) and remained relatively stable for the 30 days storage time. The results therefore show that the higher the cassava starch acidity the lower its viscosity, the higher its drying time and the longer its shelf-life.