Research Journal of Biotechnology

Indexed in SCOPUS, Chemical Abstracts Services, UGC, NAAS and Indian Citation Index etc.

Wish you all Happy 2024. Our journals are open access journals and no fees is charged for acceptance and publication.

All Issues

Vol. 15(8) August 2020

Bacterial biocontrol induced suppression of Alternaria leaf blight incidence and plant growth promotion in Cassia angustifolia. L

Gurudevan Thiribhuvanamala, Balaraman Meena, Lakshmanan Nalina and Kandasamy Rajamani

Page No: 1-5

Abstract: The medicinal crop Cassia angustifolia L. (Senna) known for its laxative properties is greatly affected by leaf blight disease caused by Alternaria alternata (Fries) Keissler. Farmers indiscriminately use lot of pesticides for the management of this leaf blight disease. Being a medicinal crop, it was thought foremost important to devise suitable management measures by using bacterial biocontrol agents for ensuring ecofriendly approach of disease management. A field trial was conducted for the period 2015-16, 2016-17 and 2017-18 at Pannikundu village of Thirumanaglam, Madurai district of Tamil Nadu, India. In this regard, talc based formulation of bacterial biocontrol agents, Bacillus subtilis and Pseudomonas fluorescens were applied after seed treatment and foliar application at 30 and 60 days after sowing.

Results showed that seed treatment with talc based formulation of Bacillus subtilis or Pseudomonas fluorescens @ 10g/kg followed by spraying with B. subtilis or P.fluorescens @ 2 g/l on 30 and 60 DAS was effective in managing the Alternaria leaf blight with lowest disease intensity of 11.1 and 11.6 PDI with increased leaf yield (18.4 and 16.5 % increase in yield respectively) compared to control . Both these treatments recorded higher B:C of 2.9 and 2.9 compared to control ( 2.5) . The results emanated from this study depicted that the biocontrol agents act in many ways like secretion of antibiotics and induced systemic acquired resistance against Alternaria leaf blight apart from increasing the yield and B: C ratio.

Genetic variability of different potassium solubilizing fungal strains of Aspergillus from Maharashtra, India

Gore Nileema S., Navale Annasaheb M. and Ghutukade Kiran S.

Page No: 6-12

Abstract:Potassium solubilizing fungi were isolated from the rhizosphere soils of different crops from Maharashtra, India. Thirty fungal isolates are able to solubilize rock K mineral powder such as micas through the production and excretion of organic acids. On the basis of screening of potassium solubilizers, 12 fungal isolates were found to be efficient to solubilize potassium. The potassium solubilizing fungal isolates were designated KSF (Potassium Solubilizing Fungi). Based on the colonial morphology, spore characteristics and microscopic appearance, the selected efficient fungi were identified as Aspergillus sp. All the selected 12 isolates were subjected to molecular diversity within the group.

Polymerase chain reaction (PCR) based technique, involving the random amplified polymorphic DNA (RAPD) has been used for assessing the genomic variability among the selected KSF isolates. The genomic DNA of 12 Aspergillus sp. was subjected to PCR amplification using 20 random oligonucleotide primers (RUF1 to RUF 20 respectively) that showed 194 polymorphic bands. RAPD fingerprinting of Aspergillus sp. revealed polymorphism in 95.66% respectively.

Comparative evaluation of Meyerozyma guilliermondii RLV-04, Emericella sp. Xlt-11 and Pseudomonas gessardii VXlt-16 for xylitol production by Taguchi Orthogonal Array approach

Ahuja Vishal, Bhatt Arvind Kumar, Rathour Ranju Kumari, Sharma Vaishali and Rana Nidhi

Page No: 13-21

Abstract:Xylitol, a linear penta-hydroxy sugar alcohol has high industrial significance especially in the formulation of low-calorie products for diabetics. Bioproduction involving microbes seems superior over conventional metal catalysis and extraction from plants. It can also address the issue of cost-intensive process as microbes can utilize low-cost waste biomass for xylitol production. In order to select a suitable candidate for microbial/enzymatic conversion of biomass, the focus of current work was to compare the efficiency of various microbes i.e. a novel bacterial isolate ‘Pseudomonas gessardii VXlt-16’, fungus ‘Emericella sp. Xlt-11’ and yeast ‘Meyerozyme guilliermondii Xlt-04’ for xylitol production by Taguchi Orthogonal Approach. The comparison was made in terms of xylose reductase and xylitol dehydrogenase activity as well as xylitol yield.
Statistical modeling resulted in significant rise in XR activity as well as xylitol production from each isolate. The Highest xylose reductase (XR) activity (75.62±0.33 U/mg protein) was reported from Emericella sp. Xlt-11 (48.29% xylose conversion) followed by Meyerozyma guilliermondii RLV-04 with enzyme activity of 49.15±11 U/mg (51.18 % xylose conversion). Although Pseudomonas gessardii VXlt-16 did not exhibit the highest xylose reductase activity (36.41±0.33 U/mg protein) but it did show the highest XR/XDH ratio and xylose conversion (1.81 and 54.11%). The results suggested that the XR/XDH ratio is more significant than XR activity alone in determining xylitol yield. On the other hand, efficient xylose metabolism in Pseudomonas can be used for xylitol production from ligno-cellulosic biomass at higher scale after further R&D efforts.

Morphological and molecular data of Panax population found in Phu Xai Lai Leng mountainous range of Nghe an province

Phan Ke Long, Pham Van The, Tran Thi Viet Thanh, Dang Phan Hien, Phan Ke Loc, Nguyen Minh Tam and Vu Dinh Duy

Page No: 22-28

Abstract: Panax stipuleanatus is one of the susceptible species due to habitat loss and over-exploitation in Vietnam. However, little is known this species in the Phu Xai Lai Leng mountainous range in Nghe An. We identified a species from Panax specimens based on morphological and molecular data, and assessed the degree of the threatened status, and then provided guidance on conservation, management and restoration of this species in the Phu Xai Lai Leng mountainous range in Nghe An.

Morphological characters showed the identification of Panax specimens in Phu Xai Lai Leng as Panax aff. stipuleanatus C.T. Tsai and K.M. Feng. Polymorphic sequence positions among Panax clumps in Phu Xai Lai Leng and GenBank references were revealed and indicated highly identical ITS sequences among Panax specimens and P. stipuleanatus. The phylogenetic analysis of the ITS sequences showed the close relationship among studied specimens and P. stipuleanatus and formed one clade. We assessed that this species in Phu Xai Lai Leng is threatened mainly by over-exploitation for commerce even though lacking of scientific vouchers and is assessed as Critically Endangered (CR)- A1a ver 3.1 with level of population reduction > 90 % in the last 10 years based on direct observation. We identified Panax specimens at Phu Xai Lai Leng mountains as Panax stipuleanatus. These results proposed a platform for the conservation and restoration of this species in the Phu Xai Lai Leng mountainous range in Nghe An.

A study of the biopotentials of Chromolaena odorata with important evidences for using its potential in drugs

Nair Sreecha Chandran and Prabha Kumari C.

Page No: 29-34

Abstract:Chromolaena odorata also known as Eupatorium odoratum is a traditional medicinal plant that is widely used for its wound healing property. In particular, =several parts of this herb have been used to treat wounds, burns and skin infections and also in the present study the leaves of Chromolaena odorata were revealed as potent anti-oxidant with anti-bacterial and anti-fungal activity and also exhibited dose dependent DPPH and hydrogen peroxide scavenging activity.

The results evaluated that distilled water extract of the plant itself has marked anti-bacterial activity with 13mm zone against Pseudomonas aerugonisa, anti-fungal activity with 9mm zone against Aspergillus flavus and antioxidant activity with 85% scavenging activity at 200 ug concentration.

Studies on Cholesterol reduction and formulation of Cholesterol reducing probiotic microorganism

Gore Suneeti, Kalekar Saylee, Zagde Dhanashree, Talekar Nisha, Mehendale Sneha and Patwardhan Rajashree

Page No: 35-43

Abstract:Elevated blood cholesterol is a well-known major risk factor for coronary heart diseases (CHD) which is the leading cause of death all over the world. Increasing levels of blood cholesterol may lead to conditions such as heart attack, blockage of arteries, atherosclerosis, obesity, diabetes etc. The use of probiotics is a modern strategy in nutraceuticals for the prevention and treatment of hypercholesterolemia. Numerous mechanisms for hypocholesterolemia effect of probiotics have been hypothesized, based mostly on in vitro evidence.

This study evaluates the use of four Lactobacilli strains as probiotics with potential hypocholesterolemic properties. These strains were also checked for their probiotic properties like pH, bile and temperature tolerance, antibiotic susceptibility and antibacterial activity. The modified Zlatkis method was used since it uses single stable reagent and is less laborious and gave results in a very short period. Results of the modified Zlatkis method showed a significant decrease in cholesterol by Lactobacillus Casei and Lactobacillus Plantarum 84.37 % and 80.62% respectively. Lactobacillus casei was lyophilized and used in the formulation of chewing gum.

Genetic divergence among germplasms of coriander (Coriandrum sativum L.)

Ram H., Khan M.M. and Pandey V.P.

Page No: 44-50

Abstract:The objective of this study was to verify the existence of genetic diversity among germplasms of Coriandum sativum L. based on 11 characters, identifying those which contribute least for distinction of those germplasms. The present investigation was conducted during November 2010- March 2011 and 2011 November- 2012 March at Main Experimental Station of Vegetable Science, Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.). The field experiment was laid out in Augmented Block Design with 110 genotypes along with three checks in 11 blocks accommodating ten genotypes and three checks in each block. The genetic diversity in 113 coriander germplasms was estimated using two multivariate analyses.

A vastly genetic variability for the studied traits between accessions was found. Traits such as fruit weight per umbel, 1000-fruits weight and fruit weight per plant have major contributions to the induced genetic diversity. Promising germplasms were identified for future utilization in hybridization to develop high yielding genotype.

Study of Micropropagation and Gamma Irradiation Effect on Bacopa monnieri

Salfarina Ramli, Hasseri Halim, Anis Nadhira Aziram, Noor Fahimah Saari, Muhammad Nazzim Muaz Abdul Halim and Salahbiah Abdul Majid

Page No: 51-57

Abstract: Micropropagation allows rapid cultivation of plant of interest with superior quality in a controlled environment to meet the market demand compared to conventional cultivation method. In this study, 0.1 mg/ml naphthaleneacetic acid (NAA) combined with 0.5 mg/ml 6-benzylamino purine (BAP) was found as the best hormonal combination for shoot regeneration of B. monnieri leaf explants. The micropropagated B. monnieri samples from the 0.5 mg/ml BAP treatment were dried and extracted for antioxidant activity and LCMS analysis.

The extract showed antioxidant activity in both DPPH and nitric oxide scavenging assay, however the activity was low compared to synthetic antioxidant BHT and BHA. A total of 8 saponins known to B. monnieri were detected including Bacopaside I that is frequently used as marker for quality control of commercial B. monnieri preparations. Treatment with acute 25 gy gamma irradiation significantly (p<0.05) stimulated the proliferation of B. monnieri as seen from the number of leaves count which supported a propagation of B. monnieri plant from irradiated explants. Results from this study serve as a preliminary work to an extensive study that induce mutagenesis to B. monnieri using gamma irradiation and investigate the phytochemical content and pharmacological activity.

Cellular properties and multilineage potential of bone marrow mesenchymal stem cells for cartilage regeneration

Nitilapura Narendra, Rao Shama, Shetty Siddharth M., Shetty Veena A., Shetty Shantharam M. and Kumar Mohana B.

Page No: 58-65

Abstract: Bone marrow-derived mesenchymal stem cells (BMSCs) have high self-renewal and trilineage differentiation capacity which makes them a potential source for the regeneration of cartilage tissue. Hence, the present study was aimed to evaluate human BMSCs on their cellular and biological properties such as morphology, viability, proliferation and population doubling time (PDT), colony-forming-unit assay, senescence activity, cytogenetic stability, alkaline phosphatase (ALP) activity, surface marker expression, and multilineage potential towards osteocytes, adipocytes and chondrocytes. Established BMSCs (n=3) exhibited spindle-shaped morphology during primary culture and early passages but acquired characteristic fibroblast-like features later. Viability was >95% at all passages; however, BMSC1 showed decreased viability during later passages (P3-P5). PDT values were slightly higher in BMSC2 and BMSC3 when compared to BMSC1. BMSCs showed colony formation ability and positive staining pattern for ALP activity.

Further, BMSCs had a positive expression for CD29, CD90 and CD73 and negative expression for CD34 and CD45. All BMSCs were successfully differentiated towards osteocytes, adipocytes and chondrocytes upon specific induction. BMSCs were shown to be proliferative with expression of MSC-specific phenotypic markers and ability for multilineage differentiation potential. These BMSCs could possibly be used in prospective therapeutic applications in cartilage regeneration.

UV Radiation and Micelles as Enhancers of Amylase Production by Trichoderma viride

Lalitha P. and Suryakala D.

Page No: 66-69

Abstract:Amylases are enzymes of industrial and economic importance. There are several studies performed on enhancement of amylase production by various organisms, some of which include mutations by physical and chemical agents. In this study, we have investigated the effect of ultraviolet (UV) radiation on production of amylase by T. viride. We have further studied the individual and combinatorial effect of UV radiation and micelles on the enzyme activity.

There was 40.8 % enhancement in enzyme activity when micelles were added exclusively and 37 % enhancement when the culture was subjected to UV radiation alone. Interestingly, we have observed that a 20 minute exposure of the culture to UV radiation combined with addition of micelles increased the enzyme activity by 78.1%.

In vitro callus culture studies of Gymnema sylvestre R. Br. leaves for production and identification of Gymnemic acid (as Gymnemagenin) using HPTLC

Koshti Leena, Patil Darshana and Patil Avinash

Page No: 70-79

Abstract:Gymnema sylvestre R. Br. (Family: Asclepiadaceae) commonly called as Gudmar or Madhunashini is an endangered medicinal woody climber. Due to immense pharmaceutical potential of Gymnemic acid found in its leaves, the plant is widely used against various harmful ailments. Owing to its increased demand and continued over exploitation, the species is declining rapidly and is on the verge of extinction.

Hence, in the present study, an attempt has been made to explore in vitro callus culture study for production of Gymnemic acid which may lead to conservation of Gymnema sylvestre R. Br., an important medicinal plant. Callus studies were carried out on MS and WPM media fortified with plant growth regulators (PGRs) including Auxins – 2, 4-dichlorophenoxyacetic acid (2,4-D) and Cytokinins – benzylaminopurine(BAP) from four different segments of leaf lamina (apical, middle, basal and petiole) for production of Gymnemic acid. Amongst all the tested combinations, apical segment of leaf on MS medium fortified with 2mg l-1 2,4-D + 1mg l-1 BAP combination produced maximum amount of green friable callus within 25 days of incubation. It was observed that MS medium fortified with 2,4-D or BAP alone was less effective while 2,4-D in combination with BAP was very effective in inducing and proliferating the callus. Further, Gymnemic acid was identified in these callus extracts and leaf extracts by developing a comparative fingerprint profile along with the standard Gymnemic acid (Gymnemagenin) using HPTLC.

Imipenem Resistance Mechanisms in Multidrug Resistant Pseudomonas aeruginosa clinical isolates from south India

Nagaveni S., Kelmani Chandrakanth R. and Patil S.A.

Page No: 80-85

Abstract:This study reports the resistance profiles of 45 P. aeruginosa isolates from 85 burn patients (52.94%). Among them, 27(60%) of the isolates showed multidrug resistance to more than eight antibiotics and 14 (30%) isolates were found to be imipenem resistant (IMRPA). All the 45 P. aeruginosa strains screened showed resistance to ciprofloxacin, ceftazidime, cefepime and piperacillin, 96% gentamycin, 44% to tobramycin, 25% amikacin and 40% aztreonam.

However, low range of resistance was observed to imipenem 30%, ticarcillin (20%) colistin (12%) and polymyxin B 14%. Genotype examination revealed that the multidrug isolates produced the integron located integrase gene-specific (intI3) and acc(6’)-Ib gene-specific primers found to be well conserved among blaIMP-positive strains. The P. aeruginosa isolates were separated into two genotypes: genotype A had high prevalence (12 strains) than genotype B (3 strains). Routine detection of metallo beta lactamase in vitro testing along with antibiotic use may help in prevention and treatment of burn patients infected with metallo beta lactamase producing P. aeruginosa.

Nanoparticle Synthesis and Characterization of Alternanthera Sessilis (purple) and its microbial activities

Sindhu Priya K. and Amutha K.

Page No: 86-90

Abstract:Plant- mediated green synthesis of nanomaterials has progressively gained popularity due to its eco-friendly nature and co-effectiveness. In the present study, we synthesized silver nanoparticles (AgNp’s) by using an aqueous solution of Alternanthera Sessilis plant extract as bioreducing agent. The synthesized AgNp’s were characterized using various microscopic and spectroscopic analysis. The results indicated the formation of AgNp’s. Additionally FT-IR study confirmed that the A.Sessilis not only functioned as a bioreductant but also acted as a capping agent to stabilize the surface of AgNp’s.

Moreover, the effect of the amount of the plant extract on the size and the antimicrobial activity of Np’s was also assessed. It was found that by increasing amount of plant extract, the size of the Np’s was decreased. The AgNp’s were tested to examine their anti – microbial activities. The activities were tested against Pseudomonas aeruginosa and Staphylococcus aureus. These result evidently show that the inclusion of A.Sessilis extract improves the solubility of AgNp’s which leads to a significant enhancement in the toxicity of Np’s against the assessed microorganisms.

Changes in behavior, cardiac rate and acetylcholinesterase activity in tadpoles of Fejervarya limnocharis (Anura, Dicroglossidae) in response to sub-lethal exposure to fluoranthene

Bhuyan Krishna and Giri Anirudha

Page No: 91-98

Abstract:Fluoranthene, a tetracyclic compound often detected in aquatic habitats, belongs to a cluster of complex organic contaminants known as polycyclic aromatic hydrocarbons. The property of high lipid solubility makes fluoranthene more resilient and aids its easy accumulation in fatty tissues of the aquatic fauna. The toxicity repositories of fluoranthene lack data on the behavioral aspects particularly in amphibians. Therefore, the present study was aimed to assess the effects of fluoranthene in the tadpoles of Fejervarya limnocharis emphasizing behavioral response. Behavioral response is often linked with neurochemical alterations and cardiac toxicities. Hence, along with behavior analysis, cardiac rate as well as acetylcholinesterase (AChE) activity was also studied. Fluoranthene in the present study is found to be acutely toxic with 96 h LC50 concentrations as 0.11 mg/L. Sub-lethal concentrations (5 and 10 % of 96 h LC50) of fluoranthene altered the behavioral response and significantly decreased the cardiac rate as well as acetylcholinesterase activities in the tadpoles. These findings indicate that fluoranthene is a potential threat to the anuran amphibian that can also be extrapolated to other aquatic organisms. Moreover, behavioral indices are useful biomarkers of environmental contamination and can be used as reliable and cost-effective ecotoxicological tools.

Determination of gamma rays radiation dose and their effect on fennel (Foeniculum vulgare Mill.) seed germination and seedling growth

Verma A.K., Reddy K.S., Dhansekar P., Solanki R.K., Chauhan V.B.S. and Singh B.

Page No: 99-105

Abstract:An experiment was conducted to estimate the lethal dose of the physical mutagen gamma rays in fennel. This is an important seed spice of India which has low genetic variability. The recombination breeding programme is a dream for the crop due to its small flower size which hampers manual emasculation and pollination. There is immense need of high yielding dwarf varieties which are not possible without generating variability. Mutation can be an effective approach in fennel to generate genetic variability. Therefore, an experiment was carried out under controlled conditions to determine the LD50 dose in fennel for identifying most effective mutation treatment to go with. In the preliminary experiment, among the different doses of gamma rays, the maximum seed germination was noticed at 100Gy (83.78%) whereas the minimum seed germination was recorded at 500Gy (13.51%). At the dose of 200Gy the seed germination and seedling survivability were 75.68% and 48.64% respectively.

The gamma rays doses i.e. 400Gy and 500Gy were highly lethal at which none of the seedling survived. Maximum number of leaves (8.67), number of roots per plant (14.00), root length (16.10 cm), shoots length (5.63 cm) and fresh weight per plant (0.022 g) were observed at minimum dose of 100Gy followed by dose of 200Gy and 300Gy. The LD50 were seemed to be around 200Gy. Therefore, based on this preliminary experiment, 5 doses were selected between 100 to 200Gy for the determination of LD50 in fennel more accurately. Among the different doses of gamma rays, the maximum seed germination was noticed at 100Gy (82.14%) followed by 125, 150, 175 and 200Gy. The LD50 was close to 200Gy at which 69.03% seed germination and 53.57% seedlings survival were recorded. 200Gy of gamma rays was found to cause near about 50% reduction in growth parameters like number of leaves, number of root, root length, shoot length and fresh weight per plant. Therefore, it is expected that 175Gy of gamma rays would be the optimal dose for inducing useful mutation in fennel.

Statistical Optimization of Physical Parameters by Response Surface Methodology for Enhanced Production of β-Galactosidase by Lactobacillus fermentum MT468249 isolated from Kefir

Mahadevaiah Shilpa and Batra Harshvardhan

Page No: 106-112

Abstract:Response Surface Methodology (RSM) with ‘one variable at a time’ approach is used for optimization of β-galactosidase production. The statistical model was obtained by central composite design (CCD) using four variables including incubation time (10-30 minutes), temperature (30-50oC), pH (5-7) and substrate concentration (5-25 mM). It was observed that the incubation time (A), and substrate concentration (D), temperature versus pH (BC) and temperature versus substrate concentration (BD) were significant (p<0.05) for enzyme production and maximum β-galactosidase activity was achieved at 20 minutes of incubation time, 40oC temperature, pH 6.0 and 15 mM of substrate concentration.

The optimized conditions permitted the production of β-galactosidase to be enhanced from 6232.13 to 7518.51 u/ml. This model explains the interaction between different parameters and Lactobacillus fermentum MKM12, a promising organism for β-galactosidase production, which is in turn used in the production of prebiotic, galactooligosaccharides.

Evaluation of the evolutionary variations in some Actinopterygii fishes via Sox2 compared with Sox14 and COI sequence variations

Shaikh-Omar A.M., Saad Y.M. and Al-Hasawi Z.M.

Page No: 113-123

Abstract:The present study was designed for evaluating the efficiency of the Sox2 gene sequences in exploring the evolutionary variations among some Actinopterygii fishes (Cichlidae, Mugilidae, Poeciliidae and Pomacentridae) compared with Sox14 and COI sequences. DNA polymorphisms among and within the evaluated fishes were calculated. Both mitochondrial (COI) and nuclear (Sox2 and Sox14) DNA markers reliably separated the estimated fish species. The lowest distance values were calculated between Mugilidae and Cichlidae fishes.

The genetic distance values between Pomacentridae and Mugilidae were lower than the distance values between Pomcentridae and both Poeciliidae and Cichlidae. Also, the results showed that Poeciliidae is distantly related to the other evaluated fish families. The revealed results have considerable value for future Actinopterygii conservation applications and scenarios. The analysis of the three gene fragments (Sox2, Sox14 and COI) sequences could be informative for reconstructing the true evolutionary variations in these widely distributed fishes. More informative DNA markers should be developed to improve knowledge on Actinopterygii evolutionary variations and diversification. We recommend increasing more efforts focused on Actinopterygii molecular identification as a main step that could improve fish conservation.

A review on liposomal drug delivery system

Muralikrishnan R., Selvamuthukumar R., Mohankumar A., Praveen K., Swamivelmanickam M. and Sivakrishnan S.

Page No: 124-135

Abstract:Liposomes are microparticulate created from lipoidal vesicles. It absolutely was used as drug carriers in enhancing the delivery of therapeutic agents. Liposomes, that are perishable and necessary non-toxic vesicles, will encapsulate each deliquescent and lipotropic medicine and yet maintain them from the external condition that end up in degradation. Several liposomes based mostly drug strategies are within the trial, and that they are approved for clinical use. Liposome may be target on the tissues, cells and animate thing compartments with or blankly of target recognition on liposome membrane.

The grouping of liposome provides an opportunity to reinforce the therapeutic index of assorted dynamic medicine by ever changing their pharmacokinetic and pharmacodynamics parameters. The success of liposome as drug carriers is seen within the range of liposome formulation which are commercially there in the market. During this review, we tend to discuss the mechanism of liposome formation, methods of preparation, classification of the liposome, evaluation of liposome, their applications and marketed products.

A review on Endophytic bacteria and their potential pharmacological applications

Ranjitha Dhevi V. Sundar and Sathiavelu Arunachalam

Page No: 136-144

Abstract:Endophytic bacteria are the endosymbionts that live inside the host plant at least for a part of its life cycle without causing apparent disease. In most of the plant species, endophytic bacteria are actively colonizing plant tissues locally as well as systemically. It may include both gram-positive and gram-negative bacteria with diverse morphology. Bacterial endophytes can be found in various sites of the plants like root, leave, stem and seed. In a single plant, more than one type of bacterial endophytes can be seen.

Usually, the endosymbiont gives some beneficial effects to the host plants. Most of the endosymbiont help the host in resisting the environmental stress and also help to resist the pathogens. When compared to rhizospheric bacteria, endophytic bacteria have more advantage as they can stay in direct contact with the plant tissues. Some endophytes produce various extracellular enzymes, antimicrobial substances and some plant-growth-promoting hormones. This review mainly focuses on the endophytic bacteria that are associated with various host plants and their biological activities.

Genome Editing Tools in Livestock

Pathak Shalu Kumari

Page No: 145-151

Abstract:Genome editing tools enable efficient and accurate genome manipulation. An enhanced ability to modify the genomes of livestock species could be utilized to improve disease resistance, productivity or breeding capability as well as the generation of new biomedical models. Various biological molecules naturally existing in diversified species including fungi, bacteria and bacteriophage have functionalities for DNA binding and processing.

The biological molecules have been recently actively engineered for use in customized genome editing of mammalian cells. Excitingly, multiple novel methods based on the newly constructed artificial molecular tools have enabled modifications of specific endogenous genetic elements in the genome at efficiencies that are much higher than that of the conventional homologous recombination based methods.