Nidhi Srivastava

Host-mediated gene silencing of a single effector gene from the potato pathogen Phytophthora infestans imparts partial resistance to late blight disease.

RNA interference (RNAi) has proved a powerful genetic tool for silencing genes in plants. Host-induced gene silencing of pathogen genes has provided a gene knockout strategy for a wide range of biotechnological applications. The RXLR effector Avr3a gene is largely responsible for virulence of oomycete plant pathogen Phytophthora infestans. In this study, we attempted to silence the Avr3a gene of P. infestans through RNAi technology. The P. infestans inoculation resulted in lower disease progression and a reduction in pathogen load, as demonstrated by disease scoring and quantification of pathogen biomass in terms of Pi08 repetitive elements, respectively. Transgenic plants induced moderate silencing of Avr3a, and the presence and/or expression of small interfering RNAs, as determined through Northern hybridization, indicated siRNA targeted against Avr3a conferred moderate resistance to P. infestans. The single effector gene did not provide complete resistance against P. infestans. Although the Avr3a effector gene could confer moderate resistance, for complete resistance, the cumulative effect of effector genes in addition to Avr3a needs to be considered. In this study, we demonstrated that host-induced RNAi is an effective strategy for functional genomics in oomycetes.

Complete Genome Sequence of Classical Swine Fever Virus Subgenogroup 2.1 from Assam, India

ABSTRACT We report the complete genome sequence of a classical swine fever virus (genogroup 2.1), isolated from an outbreak in Assam, India. This particular isolate showed a high degree of genetic variation within the subgenogroup 2.1 and may serve as a potential reference strain of the 2.1 genogroup of classical swine fever virus (CSFV) in the Indian subcontinent.

Comparative analysis of total phenolic content and antioxidant activity of in vivo and in vitro grown plant parts of Carica papaya L.

Abstract Papaya (Carica papaya L.) is known to contain significant amount of phenolic compounds, alkaloids, glycosides and vitamins, which are responsible for its antioxidant activity. The objective of this study was to compare the variations in antioxidative and radical scavenging potential of aqueous leaf extracts of regenerated plant (in vitro) and green house grown plant (in vivo) of Carica papaya L. (var. Pusa Dwarf). In order to quantify the antioxidant activity, extracts were evaluated for 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant potential and superoxide dismutase activity. The total phenol content was determined by using Folin–Ciocalteu method. In all assays in vitro leaf extract showed highest radical scavenging activity. In vitro leaf samples were also found rich in phenolic content in comparison to callus and in vivo leaf samples.

Plant-Derived Enzymes: A Treasure for Food Biotechnology

Abstract Enzymes are highly specific biological catalysts involved in food biotechnology. Enzyme production and application in the food manufacturing industry are based on a profound understanding of the enzymes in traditional foods. Plant-derived enzymes include amylase, invertase, papain, bromelain, ficin, lipoxygenase, etc. These enzymes have played an important part in food production, for example, syrups, bakery products, alcoholic beverages, dairy products, etc. Besides the use of plants as a factory for enzyme production in the food industry, they can also serve as raw material (enhancer) for the enhancement of microbial enzyme activity employed in the food industry. New approaches such as direct genetic modification are now in progress that might significantly contribute to the improvement of the nutritional value of plant-derived foods or the quality of food using enzymes derived from plant sources. Earlier enzymes were isolated from living cells (plants and animals), which led to their large-scale commercial production and wider application in the food industry. Today, microorganisms are the most important source of commercial enzymes. However, the safety of the source organism is the primary consideration in assessing an enzyme product. Food animals and edible plants have a history of safe use as sources of enzymes for the food industry.

Effect of Decortication and Heat pretreatment on Oil content extracted from Safflower Seeds variety PBNS-12

Sustainable development has improved the quality of life associate with requirement, production and processing of agricultural belongings among other things. Processing aim is to improve quality and concentration of products with their nutritional value influencing its cost also. Safflower oil is a value added product of safflower seeds which have biotechnological importance in the field of food and pharmaceutical industry. The presence of antinutritional factors (ANFs) like tannin, phytate and phenolic glucosides reduce the qualitative value of safflower seed oil. Different processing methodologies like boiling (temperature based pretreatment), decortications have been employed to reduce level of ANFs in safflower seeds. In our study, combinatorial effects of boiling and decortications have been employed to improve oil content in safflower seeds by reducing level of tannin. The boiling pretreatment was done with two sets of seed samples i.e. corticated and decorticated seeds. Each set was divided into four portions i.e. B10, B20, B30 and C. Samples B10, B20 and B30 were heated for 10 min, 20 min and 30 min respectively at 800C, while sample C served as the control for the experiment. The results showed an enhancement in percentage oil content by 1.16 fold and reduction in tannin content by 0.78 fold from B10 to B30 in corticated and decorticated set of seeds after boiling treatment. The combinatorial pretreatment methods using decortication with boiling treatment increase two fold oil content and 1.12 fold reduction in tannin content than control corticated

Association of AGTR1 (A1166C) and ACE (I/D) Polymorphisms with Breast Cancer Risk in North Indian Population

Renin angiotensin system (RAS) comprising Angiotensin converting enzyme (ACE), Angiotensin II (Ang II) and its receptor Angiotensin II receptor type I (AGTR1), plays a critical role in several diseases including cancer. A single nucleotide polymorphism (SNP) A1166C located in 3′ untranslated region (UTR) of AGTR1 and an insertion/deletion (I/D) polymorphism present in intron 16 of ACE gene have been associated with many diseases, but their association with Breast cancer (BCa) is still debatable. Here, we for the first time investigated the association of these polymorphisms in a North Indian BCa cohort including 161 patients and 152 healthy women. The polymorphisms were evaluated by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) respectively. The association between these polymorphisms and BCa risk was estimated by calculating Odds Ratio (OR) and chi-square (χ2) test. The DD genotype/D allele of ACE (I/D) polymorphism and “AC and CC” genotype/C allele of AGTR1 (A1166C) polymorphism were associated with higher risk of BCa when evaluated independently. Furthermore, interaction analysis of “AC and CC” and DD genotype and combination of “C and D” alleles of both polymorphisms revealed significantly greater BCa risk than that observed independently. Conclusively, women harboring “AC or CC” genotype/C allele for AGTR1 (A1166C) polymorphism and DD genotype/D allele for ACE (I/D) polymorphisms have a predisposition to develop more aggressive disease with advanced staging and larger tumor size. Our study indicates importance of genetic screening based on these polymorphisms for women, who may have higher risk of BCa.

Vicilin—A major storage protein of mungbean exhibits antioxidative potential, antiproliferative effects and ACE inhibitory activity

Enzymatic hydrolysates of different food proteins demonstrate health benefits. Search for diet related food protein hydrolysates is therefore of interest within the scope of functional foods. Mungbean is one of the popular foods in India because of rich protein source. In this study, mungbean vicilin protein (MBVP) was enzymatically hydrolysed by alcalase and trypsin under optimal conditions. We have studied the antioxidant, antiproliferative and angiotensin-converting enzyme (ACE) inhibitory activities of mungbean vicilin protein hydrolysate (MBVPH) vis-a-vis alcalase-generated mungbean vicilin protein hydrolysate (AMBVPH) and trypsin-generated mungbean vicilin protein hydrolysate (TMBVPH). The results showed that MBVPH exhibited higher antioxidant potential, ACE inhibitory and antiproliferative activities than MBVP. The alcalase treated hydrolysate displayed highest ACE inhibitory activity with IC50 value of 0.32 mg protein/ml. The MBVP showed significant antiproliferative activity against both MCF-7 and MDA-MB-231 breast cancer cells at the doses between 0.2–1.0 mg/ml. The data suggested that MBVPH can be utilized as physiologically active functional foods with sufficient antihypertensive activity. The results indicate that mungbean can be utilized as a rich resource of functional foods.

Characterization of Pyrrolidine Alkaloids of Epipremnum aureum for Their Antitermite Activity Against Subterranean Termites with SEM Studies

Epipremnum aureum (Linden and Andre) G.S. Bunting (E. aureum) is an ornamental foliage rich in phytoconstituents and serves as a potential source of bioactive compounds possessing beneficial biological activities. The present study was carried out to isolate the pyrrolidine alkaloids of leaves with in vitro antitermite and antirepellant efficacy on paper and soil by direct-choice and no-choice assay. Spectrometric analysis of alkaloid fractions via Ultraviolet–visible spectroscopy (UV–VIS), Fourier transform infrared spectroscopy (FTIR) and gas chromatography mass spectrometry (GC–MS) helped in the characterization of pyrrolidine alkaloids. Superior antitermite activities were observed, associated with high levels of 5-Oxoproline as compare to Methyl 5-oxo-2-pyrrolidinecarboxylate. Presence of higher contents of 4-Morpholineethanol showed effective antitermite activity and even low levels of 3-Amino-4-Hydroxybutanoic acid and 1H-1,2,4-Triazol-3-amine, N-methyl- also exposed significant activities for repellence and mortality of termites. Repellence and percentage mortality of termites by these alkaloid fractions were similar in results when compared with the standard alkaloid Nicotine and chemical termiticide Monocrotophos. These findings were also supported by SEM studies. Pyrrolidine alkaloids present in E. aureum have exposed strong in vitro antitermite and antirepellant activities against subterranean termites Odontotermes obesus. These findings strongly support the use of E. aureum to bear potential termiticidal properties, however further details need to be carried out.

In vitro biochemical study of safflower (Carthamus tinctorius L. var. SSF-708) under hyperaccumulation of copper

Todays anthropogenic activities have introduced increased concentration of heavy metals in the environment. Copper being as an essential micronutrient for the growth can also show an adverse effect on morphology and biochemical activities of plants in its higher concentration. Current study was to find out the copper induced changes and their effect on morphological and biochemical constituents in safflower. Safflower seeds were grown in Hoaglands medium containing various concentrations of copper sulfate (25, 50 and 100μM) along with control. The seedlings were harvested after every 10th and 20th days. The morphological study revealed the effect of copper by declining the growth of seedlings in its higher concentration. The growth of the roots was found to be severely retarded with curling and negative geotropic effect and yellow color leaves after 20th day of harvesting in its higher concentration. In response to excess copper, the safflower leaves exhibited a significant increase in total polyphenol, flavonoid, proline. The level of lipid peroxidation was found to be less at 10th day while it was significantly elevated at 20th days seedlings.