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RISS 인기검색어
- 검색키워드
- 저자 : Rahul Joshi (검색결과 28 건)
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Rahul Joshi,Sushma Kholiya,Himanshu Pandey,Ritu Joshi,Omia Emmanuel,Ameeta Tewari,김태현,조병관 충남대학교 농업과학연구소 2023 Korean Journal of Agricultural Science Vol.50 No.4
Terpenoids, also referred to as terpenes, are a large family of naturally occurring chemical compounds present in the essential oils extracted from medicinal plants. In this study, a nondestructive methodology was created by combining ATR-FT-IR (attenuated total reflectance- Fourier transform infrared), and Raman spectroscopy for the terpenoids assessment in medicinal plants essential oils from ten different geographical locations. Partial least squares regression (PLSR) and support vector regression (SVR) were used as machine learning methodologies. However, a deep learning based model called as one-dimensional convolutional neural network (1D CNN) were also developed for models comparison. With a correlation coefficient (R2) of 0.999 and a lowest RMSEP (root mean squared error of prediction) of 0.006% for the prediction datasets, the SVR model created for FT-IR spectral data outperformed both the PLSR and 1 D CNN models. On the other hand, for the classification of essential oils derived from plants collected from various geographical regions, the created SVM (support vector machine) classification model for Raman spectroscopic data obtained an overall classification accuracy of 0.997% which was superior than the FT-IR (0.986%) data. Based on the results we propose that FT-IR spectroscopy, when coupled with the SVR model, has a significant potential for the non-destructive identification of terpenoids in essential oils compared with destructive chemical analysis methods.
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( Rahul Joshi ),( Ritu Joshi ),( Santosh Lohumi ),( Byoung-kwan Cho ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1
The Grignard reagent is an organometallic reagent with a general formula RMgX where X is a halogen and R is an alkyl or aryl group (on the basis of benzene ring) obtained by the reaction of halogenoalkane in presence of magnesium and diethyl ether. It is a key reagent which is required in the formation of new C-C bond in the chemical compounds. Further, the Grignard reagent is the active pharmaceutical ingredient in API and thus played a very important role in drug formation in the pharmaceutical industries. Since during the preparation of the reagent, some impurities were developed which is generally undesirable and due to this, the quality of the reagent is readily affected. Analytical techniques like HPLC and Gas chromatography were generally used for determining the quality attributes of the reagent. Thus, there is a need to develop a technique which will overcome all these limitations for the quality determination of the Grignard reagent. Raman spectroscopy is considered to be the most promising analytical technique in the sector of the food industry and additionally used in the chemical analysis of the substances. So, the objective of this study is to demonstrate Raman spectroscopy as a rapid, noninvasive, and high-throughput system for measuring the following parameters within the spectral range from 1800-900cm-1. A net analyte signal (NAS)- based methodology, named HLA/GO (hybrid linear analysis) and has been used as a data analysis method for the acquired spectral data. For making the standard, samples were diluted in toluene within the concentration range from (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25 and 30%) and 10 replicates has been selected for each group during the acquisition of the spectral data. For the reference analysis, titration method will be used for the impurity identification. The whole process for the experiment i.e the standard sample preparation and the titration is going to be done inside the chemical fume hood in order to avoid the risk during the experiment causes due to the toxicity of the used reagents. Thus, the study suggests that Raman spectroscopy coupled with HLA/GO method can be used to rapidly determine the active content in the Grignard reagent and identity confirmation non-destructively and could be used as an alternative technique and the developed method eliminates any safety concern due to direct exposure to the Grignard reagent.
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Raman spectroscopic analysis to detect olive oil mixtures in argan oil
Rahul Joshi,조병관,Ritu Joshi,Santosh Lohumi,Mohammad Akbar Faqeerzada,Hanim Z Amanah,이재영,모창연,이훈수 충남대학교 농업과학연구소 2019 Korean Journal of Agricultural Science Vol.46 No.1
Adulteration of argan oil with some other cheaper oils with similar chemical compositions has resulted in increasing demands for authenticity assurance and quality control. Fast and simple analytical techniques are thus needed for authenticity analysis of high-priced argan oil. Raman spectroscopy is a potent technique and has been extensively used for quality control and safety determination for food products In this study, Raman spectroscopy in combination with a net analyte signal (NAS)-based methodology, i.e., hybrid linear analysis method developed by Goicoechea and Olivieri in 1999 (HLA/GO), was used to predict the different concentrations of olive oil (0 - 20%) added to argan oil. Raman spectra of 90 samples were collected in a spectral range of 400 - 1400 cm-1, and calibration and validation sets were designed to evaluate the performance of the multivariate method. The results revealed a high coefficient of determination (R2) value of 0.98 and a low root-mean-square error (RMSE) value of 0.41% for the calibration set, and an R2 of 0.97 and RMSE of 0.36% for the validation set. Additionally, the figures of merit such as sensitivity, selectivity, limit of detection, and limit of quantification were used for further validation. The high R2 and low RMSE values validate the detection ability and accuracy of the developed method and demonstrate its potential for quantitative determination of oil adulteration.
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Two new records of Casminola from India (Lepidoptera: Nolidae:, Nolinae)
Rahul Joshi,Navneet Singh,Nikhil Kuni 국립중앙과학관 2022 Journal of Asia-Pacific Biodiversity Vol.15 No.2
Two species, Casminola arminbecheri László, Ronkay & Witt, 2010 and Casminola johannstumpfi László, Ronkay & Witt, 2010, are reported for the first time from India. Images of the adults and genitalia are provided. A checklist of all the known species of the genus is also provided.
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( Rahul Joshi ),( Byoung-kwan Cho ) 한국농업기계학회 2021 한국농업기계학회 학술발표논문집 Vol.26 No.1
Moringa, a plant belonging to a family of Moringaceae, is commonly cultivated crop in India, and Africa and is now widely grown crop in other parts of the world. It is enriched with various nutrients, antioxidants and phytochemicals (phenolic compounds) which provide several health benefits. However, the phenolic compounds mesurement are still performed using destructive methods like HPLC and mass spectrometry which are time consuming and expensive. Thus, there is an urgent need of an alternative approach which can cope over the expensive destructive methods. Hence, the main aim of this study is to investigate the feasibility of Fourier Transform Infrared spectroscopy (FT-IR) for the non-destructive measurement of phenolic compounds in moringa leaf powder samples using chemometric methods. 250 leaf powder samples will be prepared by mixing five different varieties of moringa powder with different phenolic concentrations. The chemometric analysis is going to be performed by the application of partial least squares regression (PLSR) and support vector machine (SVM) regression methods. Based on the spectral data analysis, we believe that FT-IR spectroscopy when combined with certain chemometric approaches will be an effective alternative tool for the quantitative measurement of phenolic compounds in moringa leaf powder in a fast and non-destructive manner and therefore serve as a powerful quality control tool.
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( Rahul Joshi ),( Byoung-kwan Cho ) 한국농업기계학회 2021 한국농업기계학회 학술발표논문집 Vol.26 No.2
This study was designed for the non-destructive measurements of phenolics compounds in moringa powder using Fourier Transform Infrared (FT-IR) spectroscopy within 3500-800 cm-1 wavenumber range. The total phenolics content of three major phenolics compounds in moringa powder, namely, kaempferol, benzoic acid, and rutin were measured in five different varieties of moringa powder which was validated against reference high-performance liquid chromatography (HPLC) method. The spectral data analysis were performed using partial least squares regression, and net analyte signal (NAS)-based methodology, called hybrid linear analysis (HLA/GO). The obtained results for the PLS regression method based on mean normalized data resulted in better performance compared to different pretreatment methods, with correlation coefficients (R2p) of 0.850 and root mean square error of prediction (RMSEP) of 0.287 mg/g respectively. The results acquired through HLA/GO method performed much better than PLS regression with higher correlation coefficients (R2p) value of 0.902 and lowest error of prediction (RMSEP) of 0.212 mg/g using Savitzky-Golay 1st derivative preprocessing. Based on the results, we concluded that FT-IR spectroscopy when combined with suitable multivariate regression analysis method could be an alternative and fast analytical tool for the quantitative evaluation of phenolics compounds in moringa powder in a non-destructive manner.
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Effects of the storage environment on the quality attributes of eggs with a washing treatment
Ritu Joshi,Rahul Joshi,Mohammad Akbar Faqeerzada,박은수,배형진,이재용,이재영,김현태,조병관 충남대학교 농업과학연구소 2019 Korean Journal of Agricultural Science Vol.46 No.3
The term quality or freshness of eggs in industrial production still poses concerns regarding whether washing is necessary. Therefore, the aims of this study were to examine the effects of different storage times and temperatures and to perform a comparison between washed and unwashed eggs. A total of 1000 washed and 1000 unwashed egg samples were stored at three different temperatures (5, 10, and 25℃) for 0 - 8 weeks and were used for the data collection. On the designated day, the eggs were processed to evaluate their internal and external quality traits, such as the Haugh unit, airspace volume, eggshell strength, pH, and microbiological profile. Significant differences (p < 0.05) were observed between the washed and unwashed eggs for each quality trait. The results indicate that storage between 5 and 10℃ better preserved the quality of eggs compared with the storage at 25℃ throughout the days of the storage. Overall, this study suggests that the storage time and temperature have a vital role in maintaining the quality of eggs which were significantly affected during storage. In addition, all the quality parameters differed between the washed and unwashed samples which is further responsible for deteriorating the quality of the eggs.
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Evaluation of benzene residue in edible oils using Fourier transform infrared (FTIR) spectroscopy
Ritu Joshi,조병관,Santosh Lohumi,Rahul Joshi,이재영,이훈수,모창연 충남대학교 농업과학연구소 2019 Korean Journal of Agricultural Science Vol.46 No.2
The use of food grade hexane (FGH) for edible oil extraction is responsible for the presence of benzene in the crude oil. Benzene is a Group 1 carcinogen and could pose a serious threat to the health of consumer. However, its detection still depends on classical methods using chromatography which requires a rapid non-destructive detection method. Hence, the aim of this study was to investigate the feasibility of using Fourier transform infrared (FTIR) spectroscopy combined with multivariate analysis to detect and quantify the benzene residue in edible oil (sesame and cottonseed oil). Oil samples were adulterated with varying quantities of benzene, and their FTIR spectra were acquired with an attenuated total reflectance (ATR) method. Optimal variables for a partial least-squares regression (PLSR) model were selected using the variable importance in projection (VIP) and the selectivity ratio (SR) methods. The developed PLS models with whole variables and the VIP- and SR-selected variables were validated against an independent data set which resulted in R2 values of 0.95, 0.96, and 0.95 and standard error of prediction (SEP) values of 38.5, 33.7, and 41.7 mg/L, respectively. The proposed technique of FTIR combined with multivariate analysis and variable selection methods can detect benzene residuals in edible oils with the advantages of being fast and simple and thus, can replace the conventional methods used for the same purpose.
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Rapid Evaluation of Lead Oxide Contamination in Paprika Powder using Raman Spectroscopy
( Ritu Joshi ),( Rahul Joshi ),( Byoung-kwan Cho ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1
Color is an important quality parameter in spices as it indicates the freshness and purity of spices which losses due to over time that makes it as a major target of adulteration. Paprika powder is used as an ingredient in numerous dishes around the world. Lead oxide, used as a contaminant in paprika powder for influencing the color. When consume it can easily dissolve in the hydrochloric acid present in our stomach, making it toxic upon ingestion. In this work, the feasibility of using Raman spectroscopy for rapid determination of lead oxide in paprika powder was investigated. Raman spectra in the 350-1600 cm<sup>-1</sup> region were collected for 120 paprika samples spiked with lead oxide have the concentrations: 0 (pure paprika powder), 0.02, 0.04, 0.06, 0.08 and 0.1 %, respectively. The calibration and validation data sets were designed using data from 72 and 48 samples, respectively. Developed partial least square regression (PLSR) model was applied to all collected spectral data of pure and adulterated paprika powder samples. Model-based variable selection methods combined with variable importance in projection (VIP) values and significance multivariate correlation (sMC) used to explore the optimal variables important for the predictability of adulteration. The PLSR predictive value for the sMC-based model presented a correlation coefficient value with a standard error of prediction (SEP) of 0.008%, improved than the models developed with all variables (and SEP = 0.01%) or VIP-selected variables ( and SEP = 0.009%).Thus, the obtained experimental results indicates that the proposed technique can be regarded as an effective tool compare to conventional methods for the quantitative determination of lead oxide in paprika powder.
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