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The Effectiveness of Repeated Shoot Tip Culture on Pathogens Load Reduction in Different Local Potato Genotypes in Malawi

Author(s):Nyaika J A --- Njoloma J P --- Zimba S --- Mwase W F --- Maliro M F --- Bokosi J M --- Kwapata M B 
Journal: The International Journal of Biotechnology
Publisher:
Abstract
| Pages: 91-103
Potato production in Malawi still remains low, estimated at 11t/ha as compared to the potential 40t/ha due to disease infection resulting from seed recycling. Shoot tip culture in vitro is one of the tissue culture techniques that can potentially eliminate pathogens from infected plantlets. A study was therefore carried out to evaluate the effectiveness of repeated shoot tip culture on pathogen load reduction of some selected local potato genotypes grown in Malawi. A factorial experiment was laid out in a Completely Randomized Design (CRD) in which five genotypes including Magalabada, Rosita, Simoki, Usiwawatha and Violet were evaluated. Results showed that the mother stock tubers for all genotypes were infected with multiple pathogens at different incidences and intensities. PVY had an incidence of 100% with a low intensity in all genotypes. PVX had an incidence of 100% in Rosita and Magalabada, 80% in Usiwawatha and Violet and 60% in Simoki and their intensity was very high. The incidence for PVM was 80% in Usiwawatha, 60% in Violet, 10% in Rosita and Magalabada and 3% in Simoki; and their intensity was high. The incidence for PVS was 60% for Rosita, Magalabada and Usiwawatha, 18% for Violet and 10% for simoki; with a very high intensity. PVA incidence was 100% for Usiwawatha, 60% for Violet, 18% for Rosita and Simoki, and 5% for Magalabada; with a very low intensity. PLRV incidence was 10% for all genotypes and had a very low intensity. Traces of Bacterial wilt in low intensities were detected. Potato plantlets obtained after repeated sub-culturing of over six times resulted in reduced pathogen load at (P≤0.05) for the different pathogens. The chance of reducing the pathogen load in the different genotypes was relatively high at (P≤0.05).  

Bio-Efficacy of Pupicidal Activity of Some Plant Essential Oils on Culex Quinquefasciatus and Anopheles Stephensi

Author(s):M.Ramar --- S. Ignacimuthu --- M. Gabriel Paulraj 
Journal: The International Journal of Biotechnology
Publisher:
Abstract
| Pages: 104-114
Bio-efficacy of pupicidal potential of some essential oils from seven plants (Pimpinella anisum, Cinnamomum veerum, Myrtus caryophyllus, Citrus sinensis, Thymus vulgaris, Ocimum sanctum and Vetiveria  zizanioides) was tested against the pupae of Culex quinquefasciatus and Anopheles stephensi. The pupal susceptibility test were carried out using WHO standard method. In the pupicidal assay at five different concentrations viz., 31.25, 62.5, 125, 250, and 500ppm concentrations were used andthe mortality was observed after 24-h exposure. All the tested essential oils showed moderate to good pupicidal activity. However, the maximum pupal mortality was registered at 500 ppm concentration as 100 ± 0.00% for Cx. quinquefasciatus and An. stephensi respectively. The Pupal mortality was resigered as of aniseed (87.5 ± 062%), tulsi (85.0 ± 0.72%) and cinnamom (82.2 ± 0.42%) at 500 ppm for Cx. quinquefasciatus respectively.  The efficacy results of pupal mortality of aniseed (85.2 ± 023%), tulsi (84.1 ± 0.23%) and cinnamom (80.1 ± 0.51%) at 500 ppm for An. stephensi respectively. The LC50 and LC90 of clove oil (106.3 and 313.3 ppm), tulsi (133.6 and 539.3 ppm) and cinnamon (141.0 and 575.5 ppm) against Cx. quinquefasciatus after 24 h  respectively, and LC50 values of 110.5, 144.2 and 150.1 ppm and LC90 values of 310.4, 502.3 and 603.0 ppm against An. stephensi after 24 h of treatment, respectively. The results suggest that the essential oils have potential to be used as a pupicidal activity an ideal eco-friendly approach for the control of filarial and malaria vectors, Cx. quinquefasciatus and An. stephensi as target species in vector borne diseases control programs. 

Study of Inhibition of Apha6 Gene in Acinetobacter Baumanii by Satureja and Thyme Essence with Rt-Pcr Technique

Author(s):Hossein Saghi --- Abbas Bahador --- Davoud Esmaeili 
Journal: The International Journal of Biotechnology
Publisher:
Abstract
| Pages: 115-122
Increasing isolation of multidrug-resistant Acinetobacter baumannii (MDR) has been reported in worldwide and it is recently one of the most difficult nosocomial acquired gram-negative pathogens to control and treatment.These bacteria are one of ESBL producing that great potential have for the rapid development of antibiotic resistance. The indecorous use of antibiotics is often associated with adverse effects on the human health.Because of Satureja and Thyme essence has antimicrobial properties so they can be used against infections caused by MDR Acinetobacter baumannii. With attention to increase in population and tendency to lesser use of synthetic drugs, many of these of medicinal herbs have been replaced. The present study was aimed to investigate the inhibitory effects of Satureja khuzestaniea and Thyme essence against the expression of antibiotic resistance genes aphA-6 and compare to Housekeeping DNA gyraseA in strains of Acinetobacter baumannii with RT-PCR Technique. The major components of Satureja khuzestaniea essence were carvacrol (90.88%), ρ-cymene (3.11%), ϒ terpinene (1.24%), linalool (0.91%) and Thyme essence were thymol (28.8%) and carvacrol (23.46%). Satureja khuzestaniea with MIC (0.3 μl / ml)  and Thyme with MIC (0.45μl / ml) has the effect of reducing the expression of antibiotic resistance genes aphA-6 but these are essence no inhibitory effect on the housekeeping DNA Gyrase-A gene. This study indicated that these are essence have inhibitory effects against gene expression of antibiotic resistance aphA-6 with high MIC. Because these are essence has a good inhibitory effect against MDR Acinetobacter baumanii and, aphA-6 gene expression so it can be used as therapeutic complementary no side effects against this bacterium.

Antibody Response to Cutaneous Leishmaniasis in Sudan

Author(s):Hind Mohamed Abushama --- Maathr Ibrahim Abdel Wahab --- Ahmed Mohamed Elhassan --- Omran Fadl Osman --- Hiba Salah-Eldin Mohamed 
Journal: The International Journal of Biotechnology
Publisher:
Abstract
| Pages: 123-137
The role of antibody levels in protective immunity against cutaneous leishmaniasis (CL) is largely unknown. The aim of this study is to investigate the role of antibody response against CL among Sudanese population. Fifty six clinically diagnosed CL subjects were enrolled in this study. Forty eight of them had healed scar and eight have active lesions. The leishmanin skin test (LST) was 54.7% positive. The frequency of human IL4RP2 alleles was investigated in this study. The results showed 83.9% (183 bp) and 16.1% (253 bp) and the heterozygosity was 39%. The mean antibody levels using direct agglutination test (DAT) has found to be higher against Leishmania major (L. major) antigen than Leishmania donovani (L. donovani) antigen and the difference was found to be significant (P = 0.01 <0.05). The anti L. major IgG was quantified in this study using enzyme linked immunosorbent assay (ELISA). The mean of antibody levels measured by ELISA and DAT was significantly higher in study participants with scars more than those with skin lesions. Overall this outcome would be supportive to indicate a possible role of antibody-mediated protection in CL and would signify the importance of identification of antigens that may elicit protective antibodies.

Investigation of the Role of Two Bacterial Species in the Removal of Sulphate from Wastewater

Author(s):Akpor OB --- Vincent TZ --- Olalekan AP 
Journal: The International Journal of Biotechnology
Publisher:
Abstract
| Pages: 138-150
The aim of this study was to investigate the optimal conditions for sulphate from wastewater by Escherichia coli and Psendomonas aeruginosa under shake flask conditions. Before inoculating with the respective isolates, the wastewater was first filtered in 200 mL quantity into 250 mL capacity and then sterilized in an autoclave. After inoculation with the test isolates, aliquot wastewater samples was aseptically removed from each flask, every 24 h, for 96 h, for the estimation of sulphate concentration, using procedures. The results revealed sulphate removal at 35 oC and 45 oC while at 25 oC, an increase in sulphate level in the wastewater was observed at the end of the 96 h incubation period. This trend was irrespective of the test bacterial species. At the different pH, sulphate decreases of 50.31 %, 26.67 % and 18.14 % at pH 6, 8 and 10 were observed in the presence of the Escherichia coli while in the presence of the Pseudomonas aeruginosa, sulphate decreases of 31.53 % and 21.52 % were observed at pH 6 and 8, respectively. With the different concentrations of sodium acetate that were used for investigation, maximum sulphate removal was observed at 10 g/L. This trend was also irrespective of the test isolates. In presence of the different external carbon sources, sulphate concentrations in the wastewater after the 96 h incubation period were observed to increases at the expiration of incubation. Yeast and meat extracts were observed to enhance sulphate removal in the presence of the Escherichia coli while in presence of the Pseudomonas aeruginosa, remarkable sulphate removal was only observed when yeast extract was used as the nitrogen source. There was no decrease in sulphate level at the different concentrations of peptone that were investigated. This trend was common in presence of both isolates. The study was able to reveal the roles of temperature, pH, carbon and nitrogen concentrations and carbon/nitrogen sources on sulphate removal from wastewater by the test is bacterial species under the experimental conditions used for investigation. 

Generation and Genetic Analysis of Transgenic Maize (Zea Mays L.) Resistant to Herbicide Glyphosate

Author(s):Liyan Yang --- Yi Sun 
Journal: The International Journal of Biotechnology
Publisher:
Abstract
| Pages: 151-159
Two new glyphosate-resistant genes from different sources were introduced into a maize hybrid, Hi-II by Agrobacterium-mediated transformation, and the transgenic T0 plants were identified by 2% glyphosate application and PCR detection. Their progeny inheriting stability was determined with Southern-blot hybridization and the transgene segregation ratios were recorded by glyphosate screening.Results showed that the glyphosate-resistant genes were integrated into maize genome which conferred the transgenic plants higher glyphosate tolerence. Transgenic gene in pAX1677 T1 plants followed Mendelian segregation model while it was not the case in pAX1676 T1 plants. Development of T1 plants showed construct pAX1677 excelled to pAX1676.

Molecular biomarkers in the clam (Corbicula fluminea) and snail (Viviparus bengalensis) induced by acute exposure to Zn and Pb

Author(s):Ayad M. J. Almamoori, Jasim M. Salman, A. Randall Hughes, Ali Hmood AL-Saadi
Journal: Global Journal of Bio-Science and Biotechnology
Publisher:Society for Science and Nature
Abstract
| Pages: 135-138
Two Molluscs species (Viviparus bengalensis and Corbicula fluminea ) induced by acute exposure of Zn and Pb for different concentrations (20, 50, 100 μg/l) to monitor Molecular biomarkers response (DNA damage) , this monitoring adapted to evaluate the heavy metals stress in these species to get the early signal warning, DNA fragmentation test showed the highest DNA lysis level (9200) have recorded for snail after Zn exposure (100μg/l) at 96hr , as supporting for these results , comet assay index revealed the highest comet index after after Zn exposure for both Snail & Clam and according to according to Tail length , DNA tail moment and Classes of damage .

Correlation of geophysical and geotechnical investigations for seismic hazard assessment in Dhaka city, Bangladesh

Author(s):Md. Shakhawat Hossain, B.M. Rabby Hossain, A.K.M Fayazul Kabir, A.S.M Woobaid Ullah, A.S.M Maksud Kamal, Chowdhury Quamruzzaman
Journal: Global Journal of Bio-Science and Biotechnology
Publisher:Society for Science and Nature
Abstract
| Pages: 139-144
In order to assess seismic hazard for Dhaka city, an approach has been conducted by correlating geophysical (PS logging, shallow seismic and micro tremor) and geotechnical (SPT) methods. In this research work seven sites have been selected where both geophysical and geotechnical surveys have been conducted. From PS logging, SPT and Shallow Seismic (without source) S-wave velocity is calculated. Micro tremor method is used to determine predominant period and amplification. S-wave velocity is converted to AVS30 ( average S-wave velocity to 30m) and then amplification because there is a relation between S-wave velocity and amplification, generally low S-wave velocity gives high amplification and high S-wave velocity gives low amplification. To accomplish the objective, the four methods have been correlated based on AVS30 and amplification. The AVS30 derived from PS logging, shallow seismic and SPT gives more or less similar values but amplification derived from micro tremor analysis deviates moderately to highly, the possible reason for this deviation may be noise or instrumental errors.

Phytochemical and antibacterial properties of spices against food borne bacteria with special reference to Parmelia perlata

Author(s):Sibi G, Apsara V, K. Dhananjaya, K.R. Ravikumar , H. Mallesha
Journal: Global Journal of Bio-Science and Biotechnology
Publisher:Society for Science and Nature
Abstract
| Pages: 145-149
Spices have effective antimicrobial potentials and in the present study, fourteen spices have been tested for their efficacy against food borne bacteria under in vitro conditions. Methanolic extracts were used to determine phytochemical and antibacterial properties of the spices. Phytochemical analysis of the spice extracts explored that glycosides, steroids and terpenoids as the major phytochemicals present. Activity of spice extracts was higher on Gram positive bacteria when compared to Gram negative ones. Well diffusion assay revealed that seven out of fourteen spices tested had effective antibacterial activity against the pathogens. Minimum inhibitory concentration (MIC) assays were performed and Staphylococcus aureus ATCC 6538 (20 mm) was found as the most sensitive organism for the spice extracts tested followed by Bacillus subtilis ATCC 6633 (18 mm). Moderate resistance was exhibited by Escherichia coli ATCC 8739 and Salmonella typhimurium MTCC 3224 (5-12 mm). In general, MIC in the range of 1-16 μg ml-1 for Gram positive bacteria and 8-16 μg ml-1 for Gram negative bacteria were observed. Cardamom, cinnamon and clove also exhibited significant antibacterial activity with the MIC values of 2-8 μg ml-1 against the Gram positive bacteria food borne bacteria. Significant antibacterial activity (MIC ≤ 2 μg ml-1) of stone flower (P. perlata) against all the Gram positive food borne bacteria was observed. None of the extracts were able to control the growth of Gram negative bacteria except that of mace which has been found potential antibacterial activity against S. flexneri (MIC ≤ 1 μg ml-1).
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