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Eugenol, 4-allyl-2-methoxyphenol, a biomarker constituent of the volatile oil present in the leaves of Ocimum sanctum , and which is used topically as a dental analgesic, has been extracted from an authenticated sample of leaves from the plant and compared with a reference standard to confirm the presence of the compound. The compound from the leaves was characterized by spectroscopic analysis. The reference standard material was used for quantitative estimation of the amount of eugenol present in the volatile oil extracted from Ocimum sanctum and from a capsule formulation of Ocimum sanctum obtained commercially. A rapid, accurate, and specific HPTLC method, developed and validated in this laboratory, was used for this purpose. The method proposed can be used for routine analysis of Ocimum sanctum leaves and of herbal formulations containing the leaves.

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Abstract  

Urea-adduct process is commercially used to selectively separate n-alkanes from industrial hydrocarbon mixtures. Authors have explored application of this method for recovery of n-alkane based diluents from spent PUREX/UREX solvent. Traditionally this separation is performed by vacuum distillation, an energy-intensive process. The proposed method is simple and does not involve either exotic chemicals or complex processing steps. Application of urea-adduct process for recovery of diluent from spent solvent is reported here possibly first time in literature. Physical properties such as densities, viscosities and vapour pressure for irradiated organic solutions were also measured and reported.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors:
Kotagiri Ravikanth
,
Brijpal Singh
,
Ashish Gupta
,
Amit Singh
,
Anirudh Sharma
, and
Abhishek Kumar

With the realization of the growing popularity and demand for phytopharmaceuticals, standardization is becoming a mandatory part of the regulation of the herbal drug industry. This is applicable both to humans and veterinary formulations. Stresroak premix is a renowned polyherbal formulation for poultry. It is used as an immunomodulator, an antistress treatment, an adaptogenic, and a performance enhancer. It is a blend of Phyllanthus emblica L. (Euphorbiaceae), Withania somnifera L. (Solanacaeae), Mangifera indica L. (Anacardiaceae), Ocimum sanctum L. (Lamiaceae), and Shilajit. An HPTLC method has been established for standardization and quantification of gallic acid, mangiferin, and withanolide A in Stresroak premix. The average content of these markers in different batches of the formulation was 0.654, 0.627, and 0.325% (w/w), respectively. The method was validated for instrumental precision, repeatability, and accuracy. Average recovery of gallic acid, mangiferin, and withanolide Awas 100.41, 99.29, and 98.04% (w/w), respectively. The method is simple, precise, specific, and accurate and has potential for use in the routine quality control of the formulation and its raw materials.

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A high-performance thin-layer chromatography (HPTLC) method for the simultaneous quantitative determination of gallic acid, vanillic acid, protocatechuic acid, and quercetin in methanolic fractions of Limonia acidissima L. fruits was developed for the first time for this species. Methanol was found to be the best for the highest possible recovery of the target analytes. For achieving good separation, a mobile phase of toluene–ethyl acetate–formic acid (5:4:1 v/v) was used. The densitometric determination was carried out at 310 and 254 nm in reflection–absorption mode. The calibration curves were linear in the range of 100–600 ng per spot for gallic acid, vanillic acid, protocatechuic acid, and quercetin. The methanolic fractions of L. acidissima L. fruits showed the presence of gallic acid (0.07%), vanillic acid (0.16%), protocatechuic acid (0.06%), and quercetin (0.14%). The proposed method is simple, precise, specific, and accurate. The statistical analysis of the data obtained proves that the method is reproducible and selective and can be used for the routine analysis of the reported phenolic compounds in crude drug and extracts. The simultaneous quantification of these compounds has not been reported yet in L. acidissima L., which may be utilized for the proper standardization of the drug.

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A high-performance thin-layer chromatography (HPTLC) method for the simultaneous quantitative determination of lupeol and ursolic acid in the methanolic fraction of four different species of Bauhinia leaves was developed for the first time. For achieving good separation, a mobile phase of toluene—ethyl acetate—formic acid (8:2:0.1, v/v) was used. The densitometric determination was carried out at 550 nm and 520 nm in reflection—absorption mode for lupeol and ursolic acid, respectively, which were linear in the range of 100–600 ng per band. During the analysis, lupeol (0.15%) and ursolic acid (0.11%) were found to be the highest in the leaves of B. acuminata. The proposed method is simple, precise, specific, and accurate. The statistical analysis of the obtained data proves that the method is reproducible and selective and can be used for the routine analysis of the reported terpenoids in crude drug and extracts. The simultaneous quantification of these compounds has not yet been reported in the leaves of the studied Bauhinia species which may be utilized for the proper standardization of these species.

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A high-performance thin-layer chromatography (HPTLC) method for the simultaneous quantitative determination and validation of ursolic acid, β-sitosterol, lupeol, and quercetin in the methanolic fraction of Ichnocarpus frutescens L. was developed for the first time. For achieving good separation, a mobile phase of toluene‒ethyl acetate‒formic acid (8:2:0.1, v/v) was used. Densitometric determination was carried out at 500 nm for ursolic acid, 550 nm for β-sitosterol, 650 nm for lupeol, and 310 nm for quercetin in reflection–absorption mode, and the calibration curves were linear in the range of 100–600 ng per spot. During the analysis, the methanolic fraction of I. frutescens L. showed the presence of ursolic acid (0.34%), β-sitosterol (0.27%), lupeol (0.27%), and quercetin (0.26%). The proposed method is simple, precise, specific, and accurate. The obtained data can be used for routine analysis of reported biomarkers in crude drug and extracts. The simultaneous quantification and method validation of these biomarkers have not yet been reported in I. frutescens L., which may be utilized for the proper standardization of the plant.

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A high-performance thin-layer chromatography (HPTLC) method for the simultaneous quantitative determination of ursolic acid and β-sitosterol in the methanolic fraction of Paederia foetida L. leaves was developed for the first time. For achieving good separation, a mobile phase of toluene‒ethyl acetate‒formic acid (8:2:0.1, v/v) was used. The densitometric determination was carried out at 550 and 522 nm in reflection/absorption mode for ursolic acid and β-sitosterol. The calibration curves were linear in the range of 100-600 ng per spot for ursolic acid and β-sitosterol. During the analysis, the methanolic fraction of P. foetida L. leaves showed the presence of ursolic acid (0.12 ± 0.05%) and β-sitosterol (0.08 ± 0.12%). The proposed method is simple, precise, specific, accurate, less time-consuming, and cost-effective. The statistical analysis of the data obtained proves that the method is reproducible and selective and can be used for the routine analysis of the reported phenolic compounds in crude drug and extracts. The simultaneous quantification of these compounds has not yet been reported in P. foetida L. leaves which may be utilized for the proper standardization of the plant.

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Cereal Research Communications
Authors:
B. Kumar
,
K.S. Hooda
,
R. Gogoi
,
V. Kumar
,
S. Kumar
,
A. Abhishek
,
P. Bhati
,
J.C. Sekhar
,
K.R. Yathish
,
V. Singh
,
A. Das
,
G. Mukri
,
E. Varghese
,
H. Kaur
,
V. Malik
, and
O.P. Yadav

Maydis leaf blight (MLB), a serious foliar fungal disease of maize, may cause up to 40% losses in yield. The present studies were undertaken to identify the stable sources of MLB resistance, its inheritance study, and testing of MLB resistance linked markers from diverse background in the Indian adapted tropical maize genotypes. A set of 112 inbred lines were screened under artificially created epiphytotics conditions at three hotspot locations. Analysis across multi-locations revealed significant effects of genotypes and environments, and non-significant effects due to genotypes × environment interaction on disease incidence. A total of 25 inbred lines with stable resistance were identified across multi-locations. Inheritance of resistance was studied in six F1s and two F2s of resistant and susceptible parents. The null hypothesis of segregation of resistance and susceptible for mono and digenic ratios in two F2 populations was rejected by Chi-square test. The non-significant differences among the reciprocal crosses depicted the complete control of nuclear genome for MLB resistance. Partial dominance in F1s and normal distribution pattern in F2s of resistant and susceptible parents suggested polygenic nature of MLB resistance. Correlation studies in F2 populations exhibited significant negative correlation between disease score and days to flowering. Five simple sequence repeats (SSRs) markers, found associated to MLB resistance in different studies were unable to differentiate amongst MLB resistance and susceptible parents in our study. This emphasizes the need of fine mapping for MLB resistance in Indian germplasm. The identified stable sources of resistance and information on inheritance study can be used further in strengthening of resistance breeding against MLB.

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