Optimization of Carotenoids by Rhodotorula glutinis

Gurpreet Kaur Chandi,Sumeet Pal Singh,Balmeet Singh Gill,Dalbir Singh Sogi,Prabhjot Singh 한국식품과학회 2010 Food Science and Biotechnology Vol.19 No.4

Response surface methodology was applied to maximize the yield and productivity of carotenoids by Rhodotorula glutinis strain 1151 using supplemented tomato waste based medium. Higher concentration of tomato waste extract and yeast extract favored the production of carotenoids. In contrast to carotenogenesis higher concentration of yeast extract negatively affected the formation of biomass whereas higher amount of glucose in the medium favored biomass indicating that carotenogenesis is not correlated to biomass. The optimal concentration of medium components for maximum total carotenoids and corresponding biomass production as obtained from model were calculated to be as 660 mL/L,1.5, 4.5, 7.4, and 10 g/L for tomato extract, malt extract,yeast extract, peptone, and glucose, respectively.

Parametric study of the dry sliding wear behaviour of AA6082-T6/SiC and AA6082-T6/B4C composites using RSM

Gurpreet Singh,Sanjeev Goyal,Georgina Miranda,Neeraj Sharma 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.2

In this paper a parametric study of the wear behaviour of Aluminum matrix composites has been carried out. AA6082-T6/SiC and AA6082-T6/B 4 C composites were fabricated using stir casting technique. The percentage of reinforcement was taken as 5, 10, 15 and 20 wt.% for both SiC and B 4 C particulates. Dry sliding wear tests were conducted using pin-on-disc apparatus at room temperature and process optimization was done using Response surface methodology (RSM). Weight percentage (wt.%) of reinforcement, sliding speed, load and sliding distance were the four process parameters considered to analyse these composites wear behaviour. Analysis of variance (ANOVA) showed that sliding distance exerted the highest contribution (60.24 %) to AA6082-T6/SiC wear, followed by sliding speed (14.28 %), load (11.88 %) and reinforcement content (4.31 %). The same trend was found in AA6082-T6/B 4 C composites with slightly different contribution values, namely sliding distance (63.28 %), sliding speed (14.02 %), load (10.10 %) and reinforcement content (4.05 %). RSM analysis revealed that increases in the reinforcement content and sliding speed reduce the wear rate in both composites. On the other hand, increases in load and sliding distance led to higher AA6082-T6/SiC and AA6082-T6/B 4 C composites wear. The two predictive models were validated by conducting confirmation tests and certified that the developed wear predictive models are accurate and can be used as predictive tools for wear apllications.

Chitinolytic and Chitosanolytic Activities from Crude Cellulase Extract Produced by A. niger Grown on Apple Pomace Through Koji Fermentation

( Gurpreet Singh Dhillon ),( Satinder Kaur Brar ),( Surinder Kaur ),( Jose R. Valero ),( Mausam Verma ) 한국미생물 · 생명공학회 2011 Journal of microbiology and biotechnology Vol.21 No.12

Enzyme extracts of cellulase [filter paper cellulase (FPase) and carboxymethyl cellulase (CMCase)], chitinase, and chitosanase produced by Aspergillus niger NRRL-567 were evaluated. The interactive effects of initial moisture and different inducers for FP cellulase and CMCase production were optimized using response surface methodology. Higher enzyme activities [FPase 79.24± 4.22 IU/gram fermented substrate (gfs) and CMCase 124.04±7.78 IU/gfs] were achieved after 48 h fermentation in solid-state medium containing apple pomace supplemented with rice husk [1% (w/w)] under optimized conditions [pH 4.5, moisture 55% (v/w), and inducers veratryl alcohol (2 mM/kg), copper sulfate (1.5 mM/kg), and lactose 2% (w/w)] (p<0.05). Koji fermentation in trays was carried out and higher enzyme activities (FPase 96.67±4.18 IU/gfs and CMCase 146.50±11.92 IU/gfs) were achieved. The nonspecific chitinase and chitosanase activities of cellulase enzyme extract were analyzed using chitin and chitosan substrates with different physicochemical characteristics, such as degree of deacetylation, molecular weight, and viscosity. Higher chitinase and chitosanase activities of 70.28±3.34 IU/gfs and 60.18±3.82 to 64.20±4.12 IU/gfs, respectively, were achieved. Moreover, the enzyme was stable and retained 92-94% activity even after one month. Cellulase enzyme extract obtained from A. niger with chitinolytic and chitosanolytic activities could be potentially used for making low-molecular-weight chitin and chitosan oligomers, having promising applications in biomedicine, pharmaceuticals, food, and agricultural industries, and in biocontrol formulations.

Comparative Measurements of Physical and Mechanical Properties of AA6082 Based Composites Reinforced with B4C and SiC Particulates Produced via Stir Casting

Gurpreet Singh,Neeraj Sharma,Sanjeev Goyal,Rakesh Chandmal Sharma 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.11

AA6082/B4C and AA6082/SiC were prepared via stir casting accompanied by an inert-gas to prevent oxidation. The samplesfor both the composites were produced with varying wt% of 0, 5, 10, 15 and 20 of B4Cand SiC for their respective composites. This work gives emphasis on the comparative measurements of hardness, tensile strength, percentage elongation,Impact strength, density and porosity of the AA6082/B4C and AA6082/SiC composites. The microstructural was studiedusing X-ray diffractometer and SEM. The micro hardness in AA6082/B4C composites increases to 15.8% and the increase inAA6082/SiC composites is 11.9% only when compared with the base alloy whereas the increase in ultimate tensile strengthfor B4Cand SiC reinforced composites was reported to be 31% and 19.1% respectively. At 20 wt% of B4C,hardness andtensile strength of AA6082/B4C composite tends to decrease due to the development of clusters and increased porosity. Thetransformation in the nature of material from ductile to brittle decreases the impact strength and the resistance in the flowability presented by the hard ceramic particles lowers down the percentage elongation. Density reduces from 2.67 g/cm3 inbase alloy to 2.48 g/cm3 in AA6082/B4C and 2.56 g/cm3 in AA6082/SiC composites respectively. The formation of voids inAA6082/SiC composites makes it less porous then AA6082/B4C composites and this was because of the more agglomerationin SiC composites due to their high density.

Development of dual channel FET integrated with microheater and temperature sensor for simultaneous detection of CO2 and NO2 gases

Gurpreet Singh,Sihyeok Kim,KeekeunLee 대한전기학회 2022 대한전기학회 학술대회 논문집 Vol.2022 No.7

On the Optimization of Raman Fiber Amplifier using Genetic Algorithm in the Scenario of a 64 nm 320 Channels Dense Wavelength Division Multiplexed System

Simranjit Singh,Sonak Saini,Gurpreet Kaur,Rajinder Singh Kaler 한국광학회 2014 Current Optics and Photonics Vol.18 No.2

For multi parameter optimization of Raman Fiber Amplifier (RFA), a simple genetic algorithm is presented in the scenario of a 320 channel Dense Wavelength Division Multiplexed (DWDM) system at channel spacing of 25 GHz. The large average gain (> 22 dB) is observed from optimized RFA with the optimized parameters, such as 39.6 km of Raman length with counter-propagating pumps tuned to 205.5 THz and 211.9 THz at pump powers of 234.3 mW, 677.1 mW respectively. The gain flattening filter (GFF) has also been optimized to further reduce the gain ripple across the frequency range from 190 to 197.975 THz for broadband amplification.

Novel and effectual delivery of an antifungal agent for the treatment of persistent vulvovaginal candidiasis

Amita Sarwal,Gurpreet Singh,Shilpa Singh,Kirti Singh,V. R. Sinha 한국약제학회 2019 Journal of Pharmaceutical Investigation Vol.49 No.1

The main objective of the present work was to develop and evaluate a mucoadhesive in-situ based gel for the vaginal delivery of Fluconazole (FLZ). The formulation was developed using the cold method and evaluated for various physicodynamic and aesthetic properties. The gelling agents used were evaluated for their potential to gel FLZ without affecting its structure. The bioadhesive potential and antifungal activity of the FLZ in-situ gel was determined in comparison to the marketed antifungal topical cream, FLUCOS ®. The drug content varied from 95.3 to 98.01% and pH values were found to be slightly acidic (4.2–4.5), as normal for the vaginal milieu. The FLZ in-situ gel showed significantly higher in-vitro bioadhesion of 0.277 and antifungal activity as compared to the marketed formulation with a bioadhesion of 0.281, and did not show any signs of vaginal irritation. Thus, it can be concluded that the developed intravaginal in-situ gel formulation can be used for effective targeted treatment of vulvovaginal candidiasis (VVC) in comparison to FLUCOS ® with better mucoadhesion, drug release, permeability and drug retention characteristics with more acceptable patient compliance.

Identifying Adverse Remodeling in Hypertrophic Cardiomyopathy Phenotypes Role of Left Atrial Parameters

Dutt Shivam,Tandon Rohit,Sondh Mandeep Singh,Bansal Namita,Singh Gurbhej,Mohan Bishav,Singh Bhupinder,Wander Gurpreet Singh 아시아심장혈관영상의학회 2021 Cardiovascular Imaging Asia Vol.5 No.1

Objective: Documenting adverse remodeling in absence of left ventricular outflow tract (LVOT) obstruction and mitral regurgitation in a classical hypertrophic cardiomyopathy (HCMP) phenotype is difficult. Changes in the left atrium (LA) are a consequence of progressive left ventricular (LV) fibrosis and have been shown to progress in a linear fashion. Therefore, studying LA changes for identifying adverse remodeling in HCMP patients is important. Materials and Methods: This was a prospective study which included HCMP patients and age- and gender-matched controls. Various echocardiographic parameters of adverse cardiac remodeling were investigated. Results: A total of 160 patients with HCMP and 75 age- and sex-matched controls were analyzed over a 5-year period. HCMP patients had an enlarged LA, greater segmental thickness, and mildly increased LV filling pressure. Patients with maximum LA volume >40 mL and global LA strain <21.5% showed greater maximum segmental thickness and increased ratio of pulse wave Doppler derived mitral E wave and tissue Doppler derived annular e wave with reduced LA strain and LV strain, LA emptying fraction, and strain-derived LV ejection fraction. In both groups, significant difference was not observed in age, sex, HCMP phenotype, presence or absence of LVOT obstruction, LV volume, and mitral Doppler ratio of pulse wave Doppler derived mitral E and A waves. Conclusion: Monitoring HCMP in asymptomatic patients is challenging. Assessment of adverse cardiac remodeling in classical HCMP phenotype is feasible using global LA strain and maximum LA volume. Global LA strain identifies early changes and maximum LA volume late changes of cardiac remodeling and therefore provide an early indication of disease progression in asymptomatic HCMP patients.

Estimation of Respiration rate from ECG Using Canonical Components Analysis and Ensemble Empirical Mode Decomposition

Vineet Kumarand,Gurpreet Singh 보안공학연구지원센터 2015 International Journal of Bio-Science and Bio-Techn Vol.7 No.3

Electrocardiogram and Respiratory signal are correlated to each other. In this paper respiration rate has been estimated from ECG. We purpose a novel combination of Ensemble Empirical Mode Decomposition (EEMD) and Canonical Correlation Analysis (CCA) in order to remove the artifacts and we have estimated the respiratory rate from the denoised ECG by creating the envelope of the denoised signal. The canonical components corresponding to the artifacts were removed on the basis of correlation coefficient of denoised signal and ground truth signal. The MIT- Polysomonographic and Apnea-ECG databases of physionet bank were used to acquire the ECG signals. Real time Baseline wander noise from MIT-NSTDB was added to each record and the respiratory rate determined was compared with the corresponding respiratory signals. The average snr improvement in case of denoising using EEMD-CCA is 20.8989db. The average BPM error in respiration rate derived from ECG denoised from EEMD is ±2.7 BPM.

Modelling of the Thermophysical Properties in Ar-He-H<SUB>2</SUB> Thermal Plasmas with Electronic Excitation

Rohit Sharma,Gurpreet Singh,Kuldip Singh 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.6

The role of electronically excited states (EES) in the thermophysical properties of a ternary Ar-He-H<SUB>2</SUB> mixture has been examined in the temperature range from 6000 to 40000 K at pressures of p = 0.1, 1.0, and 5.0 atm in local thermodynamic equilibrium (LTE). The influence of electronic excitation was observed to be enhanced with increasing pressure, and for pressures from p = 0.1 to 1.0 atm, the enthalpy, frozen specific heat, total specific heat, electrical conductivity and electron thermal conductivity were enhanced by 1.22%, 30%, 5%, 1.5%, and 2%, respectively, whereas for pressures p = 1.0 to 5.0 atm, the enhancements in these properties were 2.8%, 20%, 6%, 4.5%, and 14.3%, respectively. At higher pressures (p = 5 atm), pronounced contributions to these properties of 11%, 62%, 26%, 18%, and 28%, respectively were noted. Due to the significant contribution of electronic excitation to these properties, considering its influence in modelling plasma processes is important.