Kinetic characterization of laccase from Bacillus atrophaeus, and its potential in juice clarification in free and immobilized forms

Lokesh Kumar Narnoliya,Neera Agarwal,Satya N. Patel,Sudhir P. Singh 한국미생물학회 2019 The journal of microbiology Vol.57 No.10

In the present study, a laccase gene (BaLc) from a lignin degrading bacterium, Bacillus atrophaeus, has been cloned and expressed in Escherichia coli. The optimal catalytic activity of the protein was achieved at 5.5 pH and 35°C temperature, measured by oxidation of ABTS. The Km and Vmax values were determined as 1.42 mM and 4.16 μmole/min, respectively. To achieve the enzyme recovery, the biocatalyst (BaLc) was covalently attached onto the functionalized iron magnetic-nanoparticles. The nanoparticles were characterized by zeta-potential and FTIR analyses. The immobilized BaLc enzyme was physico-kinetically characterized, exhibiting retention of 60% of the residual activity after ten reaction cycles of ABTS oxidation. The immobilized biocatalyst system was tested for its biotechnological exploitability in plant juice processing, achieving 41–58% of phenol reduction, 41–58% decolorization, 50–59% turbidity reduction in the extracts of banana pseudo-stem and sweet sorghum stalk, and apple fruit juice. This is the first study to demonstrate the use of nanoparticle- laccase conjugate in juice clarification. The findings suggest that B. atrophaus laccase is a potential catalytic tool for plant juice bioprocessing activities.

Impact of nasogastric tube exclusion after minimally invasive esophagectomy for esophageal cancer: a single-center retrospective study in India

Vignesh N,Vaibhav Kumar Varshney,Selvakumar B,Subhash Soni,Peeyush Varshney,Lokesh Agarwal 대한내시경로봇외과학회 2024 Journal of Minimally Invasive Surgery Vol.27 No.1

Purpose: This study examines the impacts of omitting nasogastric tube (NGT) placement following cervical esophagogastric anastomosis (CEGA) in Enhanced Recovery After Surgery (ERAS) protocols, comparing outcomes to those from early NGT removal. Methods: In a retrospective cohort of esophagectomy patients treated for esophageal cancer, participants were divided into two groups: group 1 had the NGT inserted post-CEGA and removed by postoperative day 3, while group 2 underwent the procedure without NGT placement. We primarily investigated anastomotic leak rates, also analyzing hospital stay duration, pulmonary complications, and NGT reinsertion. Results: Among 50 esophageal squamous cell carcinoma patients, 30 in group I were compared with 20 in group II. The baseline demographic and tumor characteristics were similar between both groups. The overall incidence of anastomotic leak was 14.0%, comparable in both groups (16.7% vs. 10.0%, p = 0.63). The postoperative hospital stay was significantly shorter in the no NGT group (median of 7 days vs. 6 days, p = 0.03) with similar major morbidity (Clavien-Dindo grade ≥IIIa; 13.3% vs. 5.0%, p = 0.63). There was no 30-day mortality, and one patient in each group had reinsertion of NGT for conduit dilatation. Conclusion: The exclusion of an NGT across CEGA after esophagectomy did not influence the anastomotic leak rate with comparable complications and a shorter hospital stay.

Comparative Experimental and Analytical Modeling of Impact Energy Dissipation of Ultra-High Performance Fibre Reinforced Concrete

Murali G,Venkatesh J.,Lokesh N.,Nava Teja Reddy,Karthikeyan K. 대한토목학회 2018 KSCE Journal of Civil Engineering Vol.22 No.8

This study examines the impact energy dissipation capacity of Ultra High Performance Fibre Reinforced Concrete (UHPFRC). Forthis purpose, nine different mixes were fabricated with hooked end and crimped steel fibres at a dosage of 0.5, 1.0, 1.5 and 2.0percentage and tested under pendulum impact test. The impact energy dissipation capacity is assessed based on test (Charpy U-notch)procedure suggested by ASTM E23. Also, an analytical model was adopted to predict the impact energy dissipation value ofUHPFRC and its performance is verified against experimental results. Based on the test results, the impact energy dissipationcapacity of the mixtures containing crimped and hooked end steel fibres were significantly higher than that of Plain Concrete (PC). The hooked end steel fibres had an increased impact energy dissipation capacity compared to crimped steel fibres, which implies thathooked end steel fibre is more appropriate for enhancing the impact energy dissipation of UHPFRC. Also, the modelling datacompared well with experimental data for the fibre volume fraction beyond 0.5%.

Duplicated extrahepatic bile duct (type Vb): An important rare anomaly

Vaibhav Kumar Varshney,Sabir Hussain,N. Vignesh,B. Selvakumar,Lokesh Agarwal,Taruna Yadav 한국간담췌외과학회 2023 Annals of hepato-biliary-pancreatic surgery Vol.27 No.2

Performance Comparison of a Vapor-Adsorption Cycle-Based Gas Turbine Inlet Air Cooling System for Different Refrigerants

Varuneswara Reddy Panyam,Veda Sai Kolla,Lokesh Palawat,Ayush Sahu,N. D. Banker 대한설비공학회 2018 International Journal Of Air-Conditioning and Refr Vol.26 No.1

Presently, to enhance the thermal efficiency of a gas turbine power plant, turbine inlet air cooling (TIAC) is the widely used technique. The conventional refrigeration methods like vapor compression refrigeration and evaporative cooling need electric power, hence absorption and adsorption refrigeration systems are attractive options as they can be powered using the waste heat energy of the exhaust gases. Adsorption system has advantages over absorption system like scalability, requirement of lower heat source temperature, absence of corrosion and crystallization. This paper focuses on the thermodynamic analysis of waste heat powered adsorption chiller used for the cooling of intake air to enhance the net power output of the gas turbine power plant. This paper also presents a comparative analysis of the vapor-adsorption cycle-based TIAC system for four different refrigerants viz. HFC-134a, carbon dioxide, ethanol and ammonia with the motive of finding a substitute refrigerant for HFC-134a which has a high global warming potential (GWP). The adsorption chiller is mathematically modeled in MATLAB with activated carbon as the adsorbent and each one of carbon dioxide, ethanol and ammonia as the adsorbate. The variation of the coefficient of performance (COP) and specific cooling effect (SCE) with varying adsorption temperatures is presented for each pair. The net power output and primary energy rate (PER) improvement of the gas turbine power plant at different ambient temperatures are also discussed. It is observed that ammonia can improve the power plant performance significantly better compared to the other three refrigerants at ambient temperatures less than 40 ∘ ∘C.

HIV/AIDS-related lymphoma: perspective from a regional cancer center in India

A.H. Rudresha,Pravin Ashok Khandare,D. Lokanatha,Abraham Jacob Linu,M.C. Suresh Babu,K.N. Lokesh,L.K. Rajeev,Carol Saldanha Smitha,Vaibhav Baburao Amale,C.S. Premalata,Mulchandani Nikita 대한혈액학회 2019 Blood Research Vol.54 No.3

BackgroundIndia has the third largest population of people living with HIV/AIDS (PLHA). Lymphoma is the second most common malignancy among PLHA. However, data are lacking regard-ing HIV/AIDS-related lymphoma (ARL) in India. This study evaluated the epidemiology and clinical outcomes of ARL from a regional cancer center in India.MethodsThis retrospective analysis included cases of ARL between March 2011 and September 2017. Data were obtained from patient record files for the assessment of epidemiology and clinical outcomes. Statistical analysis was performed using GraphPad Prism 6. Comparisons of subtype-specific survivals were performed using log-rank tests.ResultsOf 1,226 lymphoma cases, 80 (6.5%) were ARL. Details were available for 70 patients. The median age at diagnosis was 40.5 (9‒74) years with a male:female ratio of 2:1. AIDS-defining lymphomas (ADL) constituted 78.6% of cases, while 21.4% had non-AIDS defining lymphoma (NADL). The mean CD4 counts were 193.15±92.85 and 301.93±107.95 cells/L, respectively (t-test; P=0.0002). Extranodal involvement was present in 55.7%, B symptoms were reported in 60%, and lactate dehydrogenase (LDH) was elevated in 64.3% of patients. The median overall survival times were 6 months for plasmablastic lymphoma (PBL), 23 months for diffuse large B-cell lymphoma (DLBCL), and was not reached for Hodgkin’s lymphoma (log-rank test; P=0.0011). Other histo-logical subtype cases were too few to draw meaningful survival outcomes.ConclusionARL is a heterogeneous disease. Histologic subtype is a major determinant of the clinical outcome. ADL has significantly lower CD4 counts than those of NADL. There is an urgent and unmet need for uniform management guidelines for improving outcomes in this un-der-represented patient population.

Identification of Predominant Lactic Acid Bacteria Associated with Kunun-Zaki and Kindirmo a Traditional Fermented Food of Nigeria

Bamgbose Timothy,Sinha Swati,Abdullahi Isa O.,Inabo Helen I.,Bello Mohammed,Kori Lokesh D.,Ametefe Elmer N.,Anvikar Anupkumar R. 한국유산균프로바이오틱스학회 2022 Current Topic in Lactic Acid Bacteria and Probioti Vol.8 No.1

Human intestinal flora is very diverse; with lactic acid bacteria (LAB) existing as part of the most vital gut microbes that improve host health. The application of LAB as a whole organism or its metabolite in the case of probiotic and bacteriocin respectively is extensive. Thus, the need to always bio-prospect for newer strains of LAB is essential. This study focused on isolating LAB from kunun-zaki and kindirmo, a fermented non-alcoholic beverage of non-dairy and dairy sources respectively, explored their physiological and biochemical properties, antibiotics sensitivity pattern and identified based on their 16S rRNA sequencing. A total of eighty isolates were selected sixty-six from kunun-zaki and fourteen from kindirmo in which 93.7% were bacilli and 6.3% were spherical in shape having 68.75% and 30% homofermentative and heterofermentative pathway respectively. All isolates have the ability to utilize glucose to produce lactic acid while their tolerance to pH 3 and salt concentration at 2%, 4% and 6.5% varied widely. Thirty-four isolates based on their physiological and biochemical properties were selected for molecular identification to ascertain their genera and species. Limosilactobacillus fermentum (68%); Lactiplantibacillus plantarum (6%) and Weissella confusa (3%) were confirmed species isolated. Thus, it was concluded that traditional fermented foods such as kunun-zaki and kindirmo are a good source to bio-prospect for LAB for product development, starter culture and probiotic study.