Browsing by Author "Rajesh Kumar Pandey"

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Application of response surface methodology for the determination of optimum reaction conditions (Temperature and pH) for starch hydrolysis by α-amylase
(2011) Nivedita Jaiswal; Om Prakash; Mahe Talat; S.H. Hasan; Rajesh Kumar Pandey
α-amylase from soybean seeds was purified to apparent homogeneity by affinity precipitation via entrapment in alginate with 84% recovery and about 20-fold purification. The α-amylase activity and stability was characterized at various pH and temperature. Response Surface Methodology (RSM) using two-level-two-factor full factorial Central Composite Design (CCD) model was employed to optimize process parameters like pH and temperature which affects the kinetics of α-amylase catalyzed hydrolysis of starch. The results predicted by the design were found in good agreement (R2 = 97.85%) with the experimental results indicating the applicability of proposed model. The multiple regression Analysis and ANOVA showed the individual and cumulative effect of pH and temperature on enzyme activity indicating that the activity increased with the increase of pH unto 5.5 and temperature 75°C. Thus, the RSM was successful in determining the optimum reaction conditions for starch hydrolysis by α-amylase. © 2011 Academic Journals Inc.
Characterization and evaluation of mycosterol secreted from endophytic strain of Gymnema sylvestre for inhibition of α-glucosidase activity
(Nature Research, 2019) Amit Ranjan; Rajesh Kumar Singh; Saumya Khare; Ruchita Tripathi; Rajesh Kumar Pandey; Anurag Kumar Singh; Vibhav Gautam; Jyoti Shankar Tripathi; Santosh Kumar Singh
Endophytic fungi produce various types of chemicals for establishment of niche within the host plant. Due to symbiotic association, they secrete pharmaceutically important bioactive compounds and enzyme inhibitors. In this research article, we have explored the potent α-glucosidse inhibitor (AGI) produced from Fusarium equiseti recovered from the leaf of Gymnema sylvestre through bioassay-guided fraction. This study investigated the biodiversity, phylogeny, antioxidant activity and α-glucosidse inhibition of endophytic fungi isolated from Gymnema sylvestre. A total of 32 isolates obtained were grouped into 16 genera, according to their morphology of colony and spores. A high biodiversity of endophytic fungi were observed in G. sylvestre with diversity indices. Endophytic fungal strain Fusarium equiseti was identified through DNA sequencing and the sequence was deposited in GenBank database (https://ncbi.nim.nih.gov) with acession number: MF403109. The characterization of potent compound was done by FTIR, LC-ESI-MS and NMR spectroscopic analysis with IUPAC name 17-(5-ethyl-6-methylheptan-2-yl)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a] phenanthren-3-ol. The isolated bioactive compound showed significant α-amylase and α-glucosidase inhibition activity with IC50 values, 4.22 ± 0.0005 µg/mL and 69.72 ± 0.001 µg/mL while IC50 values of acarbose was 5.75 ± 0.007 and 55.29 ± 0.0005 µg/mL respectively. This result is higher in comparison to other previous study. The enzyme kinetics study revealed that bioactive compound was competitive inhibitor for α-amylase and α-glucosidase. In-silico study showed that bioactive compound binds to the binding site of α-amylase, similar to that of acarbose but with higher affinity. The study highlights the importance of endophytic fungi as an alternative source of AGI (α-glucosidase inhibition) to control the diabetic condition in vitro. © 2019, The Author(s).
Design of novel multi-epitope vaccines against severe acute respiratory syndrome validated through multistage molecular interaction and dynamics
(Taylor and Francis Ltd., 2019) Sukrit Srivastava; Mohit Kamthania; Rajesh Kumar Pandey; Ajay Kumar Saxena; Vaishali Saxena; Santosh Kumar Singh; Rakesh Kumar Sharma; Nishi Sharma
Severe acute respiratory syndrome (SARS) is endemic in South China and is continuing to spread worldwide since the 2003 outbreak, affecting human population of 37 countries till present. SARS is caused by the severe acute respiratory syndrome Coronavirus (SARS-CoV). In the present study, we have designed two multi-epitope vaccines (MEVs) composed of cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL) and B cell epitopes overlap, bearing the potential to elicit cellular as well as humoral immune response. We have used truncated (residues 10–153) Onchocerca volvulus activation-associated secreted protein-1 as molecular adjuvants at N-terminal of both the MEVs. Selected overlapping epitopes of both the MEVs were further validated for stable molecular interactions with their respective human leukocyte antigen class I and II allele binders. Moreover, CTL epitopes were further studied for their molecular interaction with transporter associated with antigen processing. Furthermore, after tertiary structure modelling, both the MEVs were validated for their stable molecular interaction with Toll-like receptors 2 and 4. Codon-optimized cDNA of both the MEVs was analysed for their potential high level of expression in the mammalian cell line (Human) needed for their further in vivo testing. Overall, the present study proposes in silico validated design of two MEVs against SARS composed of specific epitopes with the potential to cause a high level of SARS-CoV specific cellular as well as humoral immune response. Communicated by Ramaswamy H. Sarma. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.
Effect of metal ions, EDTA and sulfhydryl reagents on soybean amylase activity
(2011) Om Prakash; Nivedita Jaiswal; Rajesh Kumar Pandey
Effect of some metal ions, EDTA and sulfhydryl reagents on the activity of partially purified amylase (Sp. Activity 1213 U mg-1 protein) of soybean seeds were studied. Cobalt (II) and Manganese (II) exhibited marked activating effects on the activity, enhancing up to 200% of the initial activity at 2 mM concentration while Mercury (II) ions severely inhibited. Inhibition by mercury and activation by cobalt and manganese were concentration-dependent. However, other metal ions (K+, Ca2+ Mg2+ Al3+ Cu2+, Zn2+ and Fe3+) moderately increased the enzyme activity to a certain extent and then suppressed. Sodium, Cadmium and Nickel had no detectable influence on the activity. EDTA (12.5 mM) was found to be ineffective even for 1 h of incubation at 27°C suggesting that no metal ion is present in the enzyme. No marked inhibition of amylase activity with the sulfhydryl reagents was found. The stability of the enzyme to metal ions as well as EDTA suggests its promising potential for use in detergent industries. © 2011 Academic Journals Inc.
Fractional-Order System: Control Theory and Applications
(MDPI, 2023) Thach Ngoc Dinh; Shyam Kamal; Rajesh Kumar Pandey
[No abstract available]
In silico and in vitro studies: Tryparedoxin Peroxidase inhibitor activity of methotrexate for antileishmanial activity
(2013) Ravi Kumar Gundampati; Shraddha Sahu; Avinash Kumar Srivastava; Sambamurthy Chandrasekaran; Parameswara Rao Vuddanda; Rajesh Kumar Pandey; Radheshyam Maurya; Sanjay Singh; Medicherla V. Jagannadham
In order to understand the mechanism of molecular interactions at the active site of Tryparedoxin Peroxidase (Try P), homology modeling and docking studies were performed. We generated a Three-Dimensional (3D) model of target protein based on the Crystal structure of Leishmania Major Try PI (PDB ID: 3TUE) using modeler software. Docking analysis was carried out to study the effects of methotrexate on Tryparedoxin Peroxidase (Try P). Inhibition of the Tryparedoxin peroxidase interaction has become a new therapeutic strategy in treating leishmaniasis. Docking analysis was carried out to study the effects of methotrexate on Tryparedoxin Peroxidase (TryP). Tryparedoxin peroxidase of Trypanosomatidae family functions as antioxidant through their peroxidase and peroxynitrite reductase activities. The theoretical docking study, conducted on a sample previously reported for anti-cancer properties of Methotrexate at the binding site of 3D models of Tryparedoxin Peroxidase of Leishmania braziliensis (L. braziliensis Try P) examine interaction energy. Our studies indicate that Methotrexate displays potent activity against Try P with lowest binding energy and RMSD values to be -14.5879 Kcal/Mol and 2.0 A. The results of the present study clearly demonstrated the Tryparedoxin Peroxidase inhibitory activity by methotrexate in in silico docking analysis and in vitro assay which contributes towards understanding the mechanism of antileishmanial activity. © 2013 Science Publication.
Non Hazardous synthesis of graphene and its application in the preparation of L-Asparginase based biosensor obtained from Bacillus cereus strain for the detection of leukemia
(TechConnect, 2016) Mahe Talat; Rajesh Kumar Pandey; Jaganadham V. Medicherla; Onkar Nath Srivastava
High quality graphene oxide was synthesized using expanded graphite following a modified Hummer's method. This method is facile, inexpensive and avoids use of strong acids. To exfoliate, the Graphene Oxide (GO) sheets were thermally exfoliated by rapid heating at 1050°C for 30 seconds under an Argon atmosphere. Further the antileukemic enzyme Asparaginase was isolated from a bacterial source, Bacillus cereus strain BHU-MBU BC1 (ACCESSION No. KJ472206). The isolated enzyme was further purified in a single step through DEAE-Sepharose column (2.0 × 10.0 cm) at 4°C. Kinetic parameters of the as purified enzyme were thoroughly studied. As purified enzyme was further attached to graphene. It was observed that graphene conjugated enzyme showed the enhanced activity and the reusability of the enzyme was found to be 12 times retaining activity upto 80%. The temperature optima of the immobilized enzyme were also found to be improved from 45° to 60° C.
α-Amylase immobilization on gelatin: Optimization of process variables
(Academy of Scientific Research and Technology, 2012) Nivedita Jaiswal; Om Prakash; Mahe Talat; S.H. Hasan; Rajesh Kumar Pandey
α-Amylase was extracted and purified from soybean seeds to apparent homogeneity by affinity precipitation. The homogeneous enzyme preparation was immobilized on gelatin matrix using glutaraldehyde as an organic hardener. Response surface methodology (RSM) and 3-level-3-factor Box-Behnken design was employed to evaluate the effects of immobilization parameters, such as gelatin concentration, glutaraldehyde concentration and hardening time on the activity of immobilized α-amylase. The results showed that 20% gelatin (w/v), 10% glutaraldehyde (v/v) and 1 h hardening time yielded an optimum immobilization of 82.5%. © 2012 Academy of Scientific Research and Technology.