Bacteria as a source of biopigments and their potential applications.

From the prehistoric period, the utilization of pigments as colouring agents was an integral part of human life. Early people may have utilized paint for aesthetic motives, according to archaeologists. The pigments are either naturally derived or synthesized in the laboratory. Different studies reported that certain synthetic colouring compounds were toxic and had adverse health and environmental effects. Therefore, knowing the drawbacks of these synthetic colouring agents now scientists are attracted towards the harmless natural pigments. The main sources of natural pigments are plants, animals or microorganisms. Out of these natural pigments, microorganisms are the most important source for the production and application of bioactive secondary metabolites. Among all kinds of microorganisms, bacteria have specific benefits due to their short life cycle, low sensitivity to seasonal and climatic variations, ease of scaling, and ability to create pigments of various colours. Based on these physical characteristics, bacterial pigments appear to be a promising sector for novel biotechnological applications, ranging from functional food production to the development of new pharmaceuticals and biomedical therapies. This review summarizes the need for bacterial pigments, biosynthetic pathways of carotenoids and different applications of bacterial pigments.

RIG-I expression pattern and cytokine profile in indigenous ducks infected with duck plague virus.

The present study was undertaken to elucidate mRNA expression pattern of RIG-I and serum cytokines profile alterations in indigenous ducks of Assam, India viz. Pati, Nageswari and Cinahanh in response to natural infections of duck plague virus. Field outbreaks of duck plague virus were attended during the study period for collection of tissue and blood samples. The ducks under study were divided into three distinct groups as per health status i.e. healthy, duck plague infected and recovered. Results from the study revealed that RIG-I gene expression was significantly upregulated in liver, intestine, spleen, brain and PBMC of both infected and recovered ducks. However, fold changes in RIG- I gene expression was lower in recovered ducks as compared to infected ones which indicated continued stimulation of RIG-I gene by the latent viruses. Both serum pro and anti-inflammatory cytokines were elevated in infected ducks as compared to healthy and recovered ducks, indicating activation of inflammatory reactions in the ducks due to virus invasion. The results from the study indicated that innate immune components of the infected ducks were stimulated in order to make an attempt to resist the virus from the infected ducks.

Clostridioides difficile in food and food products of animal origin in Assam, India.

OBJECTIVE: Considering the paucity of information about food-associated Clostridioides difficile from India, a study was undertaken to establish the prevalence of C. difficile in a variety of foods of animal origin, together with molecular strain characterization and antimicrobial resistance. METHODS: A total of 235 samples comprising raw meat and meat products, fish products, and milk and milk products were screened for C. difficile. Toxin genes and other parts of PaLoc were amplified in isolated strains. The resistance pattern towards commonly used antimicrobial agents was studied by the Epsilometric test. RESULTS: C. difficile was isolated from 17(7.23%) different food samples of animal origin, including toxigenic (6) and non-toxigenic (11) isolates. In four toxigenic strains, the tcdA gene could not be detected under used conditions (tcdA-tcdB+). However, all strains had binary toxin-associated genes (cdtA and cdtB). The antimicrobial resistance was highest in non-toxigenic C. difficile isolates in food of animal origin. CONCLUSION: Meat, meat products and dry fish, but not milk and milk products were contaminated with C. difficile. Contamination rates were low with diverse toxin profiles and antibiotic resistance patterns among the C. difficile strains.

Polymorphism and phylogenetic analysis of FecB and FecG genes in native sheep of Meghalaya, India.

The present study was conducted to identify the polymorphism of two major fecundity genes, viz. FecB and FecG, in indigenous sheep of Meghalaya and to assess phylogenetic relationship with 15 breeds of sheep and to estimate the sequence distances between them. Blood samples were collected from 50 adult ewes and PCR-RFLP was performed to detect the polymorphism of these genes. Further digestion of FecB and FecG was done with restriction enzymes AvaII and DdeI, respectively. In the case of FecB gene, two genotypes, viz. AA and AB, were identified where AA genotype yielded one fragment (190 bp) and AB genotype yielded two fragments (160 and 30 bp). The frequencies of A and B alleles were calculated as 0.64 and 0.36 and those of AA and AB genotypes as 0.280 and 0.720 respectively, whereas FecG gene was found to be monomorphic, with only a single genotype designated as AB genotype. Measure of relatedness among Indian and exotic sheep in terms of both the fecundity genes threw light on the evolutionary origin of different sheep breeds.

Draft Genome Sequence Analysis of the Genotype II African Swine Fever Virus from India.

African swine fever virus (ASFV) entered the northeastern (NE) part of India early in 2020, causing huge economic loss to the piggery sector. Here, we are presenting a brief report on the draft genome sequence of an ASFV strain ABTCVSCK_ASF007 from Assam state of NE India belonging to genotype II.

Characterization of ß-Cryptoxanthin and Other Carotenoid Derivatives from Rhodotorula taiwanensis, A Novel Yeast Isolated from Traditional Starter Culture of Assam.

The present investigation was intended to characterize pigments for the first time from Rhodotorula taiwanensis (LC011412) yeast isolated from the ethic fermentation starter culture source meant to evaluate its carotenoid contents for beneficial applications. The pigments were extracted by an optimized solvent system, purified by flash chromatography and were identified by TLC and UV/VIS spectroscopy. The absorbance spectra confirmed the presence of ß-carotene, ß-cryptoxanthin, torulene and torularhodin that showed maximum absorbance (λmax ) within the ranges. The fractions were further characterized by LC/MS and analyzed through FT-IR and NMR for structure elucidation. Spectral analyses also confirmed the presence of the compounds mentioned above. These compounds promise great commercial value and could be useful for large scale production anticipated for potential applications in food, nutraceutical, pharmaceutical and cosmetic sectors. It is pertinent that the characterized carotenoid pigments from the isolate have incredible prospects in industrial applications which require profound attention.

Recombinant Newcastle Disease Virus (NDV) Expressing Sigma C Protein of Avian Reovirus (ARV) Protects against Both ARV and NDV in Chickens.

Newcastle disease (ND) and avian reovirus (ARV) infections are a serious threat to the poultry industry, which causes heavy economic losses. The mesogenic NDV strain R2B is commonly used as a booster vaccine in many Asian countries to control the disease. In this seminal work, a recombinant NDV strain R2B expressing the sigma C (σC) gene of ARV (rNDV-R2B-σC) was generated by reverse genetics, characterized in vitro and tested as a bivalent vaccine candidate in chickens. The recombinant rNDV-R2B-σC virus was attenuated as compared to the parent rNDV-R2B virus as revealed by standard pathogenicity assays. The generated vaccine candidate, rNDV-R2B-σC, could induce both humoral and cell mediated immune responses in birds and gave complete protection against virulent NDV and ARV challenges. Post-challenge virus shedding analysis revealed a drastic reduction in NDV shed, as compared to unvaccinated birds.

Generation and evaluation of a recombinant Newcastle disease virus strain R2B with an altered fusion protein cleavage site as a vaccine candidate.

Newcastle disease (ND) is a highly contagious and fatal disease of chickens. Newcastle disease virus (NDV) strain R2B is an Indian mesogenic strain used for secondary vaccination in chickens. Mesogenic strains have increased virulence and immunogenicity but may cause disease in vaccinated birds, thus rendering them ineffective for use. In this study, we generated a recombinant NDV by changing the fusion protein cleavage site of mesogenic rNDV-R2B from a polybasic amino acid motif RRQKRF to a dibasic amino acid motif GRQGRL leading to generation of an attenuated virus, rNDV-R2B-FPCS. The modified recombinant virus had similar growth characteristics as rNDV-R2B, but was less virulent in susceptible chickens. Immunization of the recombinant attenuated virus to one week of age SPF chickens generated a protective immune response with a substantial reduction in virus shed after challenge with virulent NDV. The results of the study indicate that the modified rNDV-R2B-FPCS virus can be used for primary immunization in birds without any adverse reactions.

Phytochemical characterization and evaluation of anticataract potential of seabuckthorn leaf extract.

OBJECTIVE: This study was undertaken to carry out phytochemical characterization of aqueous extract of Seabuckthorn (SBT, Hippophae rhamnoides L.) leaves and evaluation of its therapeutic role in oxidative stress-induced cataract in isolated goat lenses using Vit. E as reference compound. ANIMAL STUDIED: A total of 42 goat eye lenses were used in the present study. PROCEDURE: Seabuckthorn leaf extract was characterized by total phenol content estimation and HPLC analysis of quercetin and catechin. Further, cataract was induced in goat lenses using hydrogen peroxide (H2O2) and anticataract activity was evaluated using the extract in the dose range of 100, 200, 500, and 1000 µg/mL concentrations through estimation of biochemical markers such as superoxide dismutase (SOD), reduced glutathione (GSH), and malonaldehyde (MDA). RESULTS: The results of the phytochemical characterization showed the total phenol content of the extract to be 365 mg/g in terms of gallic acid equivalents. Quercetin and catechin were estimated to be 0.01 and 0.12% w/w, respectively. In biochemical analysis, H2O2 introduction resulted in a decrease in SOD (approximately 85%) and GSH (approximately 63%) contents and an increase in MDA content (approximately 300%). The decreased levels of SOD and GSH were significantly restored in experimental groups receiving 500 and 1000 1g/mL of SBT extract. All the experimental groups showed significantly reduced MDA level in all the doses. CONCLUSION: Aqueous extract of SBT leaves showed the potential to delay onset and/or progression of cataract, at least during in vitro conditions. Results indicate the possibilities of evaluating this extract for its use as anticataract agent during in vivo conditions.

Polymorphism and nucleotide sequencing of BMPR1B gene in prolific Assam hill goat.

Assam hill goat (Capra hircus) is a prolific local goat in India. bone morphogenetic protein receptor (BMPR1B) gene was studied as a candidate gene for the prolificacy of goats. The objective of the present study was to detect the incidence of mutation in the exonic region of BMPR1B gene of Assam hill goat. Total 90 blood samples were collected randomly from different parts of Assam and genomic DNA were extracted using phenol-chloroform method. The quantity and quality of extracted DNA was examined by spectrophotometry and gel electrophoresis, respectively. PCR amplicon showed a product of 140 bp fragment of BMPR1B gene. The purified product upon digestion with AvaII showed monomorphic banding pattern and revealed wild type alleles with AA genotype. Nucleotide sequencing showed one new mutation 773 (G→C) which is found to be unique in Assam hill goat. Construction of tree at nucleotide level generates from the present experiment lies in common cluster which differs from the other breeds of goat. The analysis of polymorphism for BMPR1B in Assam hill goat indicates that the genetic factor responsible for prolificacy or multiple kidding rates is not related to the reported mutated alleles of BMPR1B gene. Therefore, attempts to be made to detect other SNPs for BMPR1B gene or otherwise effort should be made towards other fecundity gene which might be responsible for the prolificacy of Assam hill goat.