Open Access Original Research Article

Investigation on the Effects of UV Radiation on Physiological Characteristics of Moringa oleifera Lam. in vitro and in situ

Asma G. Oraibi

Biotechnology Journal International, Page 1-8
DOI: 10.9734/BJI/2017/35996

Moringa oliefera seeds were treated with UV light type A, B and C for 30 minutes. Seedlings length, number of plants, number of axillary buds, number of adventitious buds and number of apical buds were recorded 34 days after sowing the treated seeds in addition to the control in vivo. Sterilized seeds were cultured in vitro on MS agar medium containing 4.0 mg/l BA for seed germination, then shoot explants were cut into small pieces and placed on the MS agar medium supplemented with 0.5 mg/l BA and 2.5 mg/l 2, 4-D. The percentage of callus induction and callus fresh weight were determined about six weeks after inoculating. Proline and carbohydrate concentrations were also determined for intact plant and callus cultures. Results showed that the physiological parameters studied in situ reduced significantly at UV-B recording 1.5, 1.8, 3.4, 2.8 and 19.3 cm No. germinated plants, No. Adventitious buds, No. axillary buds, No. apical buds and seedlings height respectively. UV-B recorded the highest mean values in relation to percentage of callus induction, callus fresh weight and proline concentration (100%, 112 mg and 9.7 µM/g respectively) compared to the control (72.3%, 93.3 mg and 7.3 µM/g respectively). A significant reduction in the mean carbohydrate concentration was observed in all UV treatments in both intact plants and callus cultures compared with control.

Open Access Original Research Article

RNA-Seq Evaluating Several Custom Microarrays Background Correction and Gene Expression Data Normalization Systems

Noel Dougba Dago, Martial Didier Yao Saraka, Nafan Diarrassouba, Antonio Mori, Hermann-Désiré Lallié, Edouard Kouamé N’Goran, Lamine Baba-Moussa, Massimo Delledonne, Giovanni Malerba

Biotechnology Journal International, Page 1-14
DOI: 10.9734/BJI/2017/36345

Microarray gene expression technologies represents a widely used tool in transcriptomics and genomics studies worldwide. Even if this technology exhibits a low dynamic range as well as a feeble sensitivity and specificity (limited performances) with respect to RNA sequencing (RNA-seq) methodology in whole transcriptomic and/or genomic studies; it is noteworthy to underline the stability of the former (microarrays) because of their well-established biostatistics and bioinformatics analysis schemes. Several studies shown that inadequate data pre-processing as regards microarray gene expression data analysis; i.e. inadequate gene expression data normalization (DN) and scarce noise background subtraction (BS), might compromise microarray aptitude in calling correctly significantly differentially expressed genes (DEGs). Here, we were interested in assessing the performance of 20 different microarrays background correction and gene expression data normalisation arrangements from R software “linear models for microarray and RNA-seq data analysis” package, by comparing the number of differentially expressed genes detected by our previous developed custom microarray designs and RNA-seq platform. The present study basing exclusively on several clustering and principal component analysis (PCA) as well as descriptive and inferential statistic surveys, developed in the R programing environment, suggested a predominance of microarray data normalisation systems with respect to noise background correction procedure. Although, all processed background subtraction and gene expression data normalization arrangement (BS+DN) claimed to improve the agreement (sensitivity) between microarrays and RNA-seq in calling DEGs; quantile normalisation procedure applied to our processed custom microarray designs has been recorded as exhibiting the best sensitivity (p-value<0.05), since discriminates the highest number of DEGs in agreement with RNA-seq as opposed to the others analysed microarray gene expression data normalisation systems. In conclusion our findings confirmed the pre-eminence of data pre-processing procedure in microarray gene expression profiling analysis according a priority to data normalisation procedure and suggested the stability of quantile normalisation system with respect to the others processed normalisation arrangements in the present executed gene expression comparative study. 

Open Access Original Research Article

Optimisation of Growth Factors for Effective Use of Phosphate Solubilizing Bacterial Strains and Its Use as Bioinoculants for the Growth of Groundnut (Arachis hypogaea) Plant

Priyanka Anbalagan, Veena Gayathri Krishnaswamy

Biotechnology Journal International, Page 1-16
DOI: 10.9734/BJI/2017/36243

Phosphorus (P) is one of the essential macronutrients for plant growth. Phosphate solubilizing bacteria (PSB) are organisms which are used as bioinoculants to enhance the plant growth. Plants take phosphate in the form of soluble orthophosphate ions but due to the presence of calcium, magnesium, potassium, sodium, aluminium and ferrous ions in soil, the soluble orthophosphate is converted in to insoluble form. Because of this process plants utilize very little amount of phosphate, even though phosphorus containing fertilizers are added to the plants. Phosphate-solubilizing bacteria (PSB) has been added as fertilizer to increase phosphorus uptake and plant growth. It is usually observed that the solubilization of phosphate by the phosphate solubilizing bacteria would drop the pH of the medium. Acidification of the medium may be due to production of organic acids by the bacterial strains. Such plant growth-promoting bacteria has the ability to produce enzymes such as Phosphatase and 1-aminocyclopropane-1-carboxylate (ACC) deaminase to lower plant ethylene levels, that often results in various stresses, which shows the efficacious functioning of these bacteria. This study aims in the optimization of growth factors of the isolated PSB strains for use as a Biofertilizers, specifically to study the effects of temperature, pH and different carbon, nitrogen sources and NaCl concentrations on phosphate solubilization ability. The results showed phosphate solubilization was expressed maximum at pH 6, temperature 25 °C, dextrose as carbon source, ammonium sulphate as Nitrogen source and (1.2%) NaCl concentration by the PSB strains. Further the PSB was applied as bioinoculants to enhance the root, shoot length and phosphorus accumulation content of ground nut (Arachis hypogaea) seedlings. Present study highlights the importance of these plants growth promoting bacterial strains and their uses for agriculture purposes as a Biofertilizer.

Open Access Original Research Article

Inhibitory Effects of 4T1 Breast Tumor Transplantation on Mouse Peripheral Blood Immune Cell Populations

Kexin Zheng, Qilong Li, Chenghao Fu, Shiliang Ma

Biotechnology Journal International, Page 1-12
DOI: 10.9734/BJI/2017/36382

Aims: One of serious threats to women's health is mammary cancer whose occurrence, development, and treatment are related to the body’s immunological circumstances. In addition, the cancer also imposes the some effects on the body’s immune system. However, the body’s response is very diverse because it varies from type to type of cancer. This paper reported that the effects of 4T1 cell transplantation on immune cells and spleen in mice.

Methods: Twenty female BALB/C mice were randomly divided into a control group and transplantation group. 4T1 cells were injected into the forth mammary fat pad to construct an animal model of breast cancer metastasis. The lymphocytes from mouse peripheral blood after transplantation and were analyzed by flow cytometry.

Results: The transplantation of 4T1 cells rapidly and continuously decreased the percentages of total T cells, total B cells, cytotoxic T cells and helper T cells in peripheral blood during experimental period (28 days). In addition, memory T cells in the transplantation group were increased at 28 days after transplantation. Only the natural killer (NK) cell percentage was significantly increased at 14 days after transplantation.

Conclusions: 4T1 cell transplantation exerted distinctive effects on the different types of immune cells in mouse peripheral blood: the transplantation of 4T1 cells decreased the levels of total T cells, total B cells, cytotoxic T cells, helper T cells and memory T cells, and the natural killer (NK) cell was increased transiently than in control group.

Open Access Original Research Article

Optimization and Lipase Production of Lysinibacillus sphaericus in Domestic Oil Rich Waste Water

Babatunde Aderiye, Adebisi Sulaimon

Biotechnology Journal International, Page 1-12
DOI: 10.9734/BJI/2017/34290

The present study investigated the growth and lipase production by Lysinibacillus sphaericus in a minimal medium. The growth conditions (i.e oil concentration, nitrogen source, carbon source, metals and non metals) were optimized for maximum production of enzyme. Influence of different culture conditions including varied environmental and nutritional conditions were tested. Lipase activity was determined by colorimetric method based on the activity in cleavage of p-nitrophenylpalmitate (p-NPP). Maximum lipase production (5.1 mM/min) was found on the fifth day of the cultured filtrate at pH 8 and temperature of 30°C. Two point five percent (2.5%) oil concentration supported highest lipase enzyme production with (6.67 mM/min). Ammonium phosphate and glucose encouraged the maximum activity/production. Optimum production of lipase (6.46 mM/mins) was exhibited by medium supplemented when cell growth is 0.286 mg/l. Also, sulphate produced lipase maximally among the non metals used. From this work, optimizing the culturing conditions and modifying the composition of the medium dramatically improved the lipase production by Lysinibacillus sphaericus. Lipase production by Lysinibacillus sphaericus is very promising and could be used for industrial purposes and biotechnology.

Open Access Original Research Article

Isolation, Identification and Characterization of Cellulase from a Bacterium Obtained at a Saw-Mill Site in Ile-Ife, Nigeria

A. E. Agbolade, E. F. Aransiola, K. O. Awojobi, M. K. Bakare

Biotechnology Journal International, Page 1-14
DOI: 10.9734/BJI/2017/37221

Cellulose continues to account for one of earth’s most abundant biomass. Cellulase degrades cellulose, thereby making it one of the most sought after enzyme in the commercial market. This research aimed to characterize cellulase with enviable physicochemical parameters from a bacterium isolated from decaying sawdust heap. Isolated bacteria species were screened for cellulolysis. The bacterium with the largest halozone was identified by its 16S rRNA sequence. Optimum growth and cellulase production condition was determined by varying selected factors. Extracted cellulase was partially purified by Ion exchange and gel filtration chromatographic methods. The kinetic parameters were determined. Effect of selected conditions on cellulase activity was studied. Isolate A8 with 58 mm halozone had 96% sequence identity with Bacillus subtilis FJ532063. Optimum activity of 46.18 U/ml at 36 hours was recorded at pH 7, 35 ± 2°C. Yields of 18.5 and 13.5% resulted from ion exchange and gel filtration chromatography respectively. Km was found to be 0.0108 ± 0.0032 mg/ml with a Vmax of 119.3 ± 7.4 µmol/min. Maximum activity for partially purified cellulase was recorded at pH 9.5 and 55°C with stability at 50°C; and pH 9, 35°C with stability at 45°C for crude cellulase. The study showed cellulase from Bacillus subtilis A8 as active and thermostable enough to be further exploited for industrial applications.