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2010 - 20152
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Subject: Chemistry × Author: Savita Rani × End date: 2017 × Start date: 2010 ×
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    ThesisItemOpen Access
    Effect of dehulling and cooking on the phytochemical profile and antioxidant activity of some pulses of Haryana
    (CCSHAU, 2015) Savita Rani; Khabiruddin, M.
    Pulse crops, rich in proteins possess not only high nutritonal composition but also are highly safe in the treatment of many diseases. In this study, quantitative determination of seed coat, dehusked raw dal, cooked dal and whole seed of locally grown pulses viz. pigeonpea, lentil, desi & kabuli chickpea, mungbean and ricebean was carried out using spectroscopic methods. Folin-Ciocalteu procedure and aluminium chloride colorimetric method were used for evaluation of total phenolic content and flavonoid content respectively. Hydrophilic phenols, hydrophobic phenols and ortho dihydrophenols were also estimated. Free radical scavenging efficiencies and antioxidant activities were analysed by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and ferric thiocyanate (FTC) assay respectively. Among the four treatments o f all the pulses, highest yield in methanol was found in whole seed extract (9.21%) of ricebean while lowest extract yield was observed in cooked dal extract (2.34%) of lentil. Total phenolic content (mg GAEg -1 ) varied from 1.72-103.62 in all of the extracts. Similarly, flavonoids (mg CAEg -1) ranged from 1.13 to 33.66 which also found to be reduced in dehulled and cooked extracts. o-Dihydric phenols, hydrophobic & hydrophilic phenols followed order as: seed coat> whole seed> raw dal> cooked dal. Results obt ained by DPPH method showed that free radical scavenging capacities of various extracts from different species of legumes ranged from 53.80 to 92.00%. Their IC50 values (mg/ml) varied from 0.16- 2.78. On the other hand, as per results by FTC method, antioxidant activity in various extracts ranged from 51.00 to 78.60%. Their corresponding IC50 values (mg/ml) varied from 0.29- 3.83. Analogous to results obtained for total phenolics, antioxidant activities were highest in seed coat and whole seed extracts. The high content of total phenolics and total flavonoids indicated that these bioactive metabolites contribute to synergistic effect for the antioxidant activity. Moreover, a highly significant correlation (p<0.05) between antioxidant activities/free radical scavenging efficiencies and phenolic contents as well as favonoids was observed in most of the extracts under study. The results concluded that the pulse seed extracts may be valuable natural antioxidant sources and are potentially applicable in both medicine and healthy food industry.
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    ThesisItemOpen Access
    Effect of column chromatography studies on quality of lemongrass (Cymbopogon flexuosus stapf) essential oil and its nematicidal activity
    (CCSHAU, 2010) Savita Rani; Madan, V.K.
    Lemongrass belongs to genus Cymbopogon (Family Gramineae Syn. Poaceae). In good quality lemongrass oil, the content of aldehyde i.e. citral-a (geranial) and citral-b (neral) should be maximum and citronellal and geraniol should be minimum. Laboratory studies were conducted to study the effct of silica gel and aluminium oxide (neutral) column chromatography on the quality of essential oil of lemongrasss (Cymbopogon flexuosus). Nematicidal activity of aqueous extracts of essential oil of lemongrass (C. flexuosus) was also studied against the root-knot nematode Meloidogyne incognita. For column chromatographic studies, silica gel (3g), aluminium oxide (neutral, 3g) and mixture of silica gel and aluminium oxide (1:1, w/w) were taken as adsorbents. Three eluants viz., hexane, carbon tetrachloride and ethanol were taken for each adsorbent. Elution was done with 60 ml of eluant and six eluant fractions (each 10 ml) were collected for each Set. Essential oils were recovered from different eluant fractions of each Set. The essential oil sample thus collected were analyzed by Gas Liquid Chromatography for quantitative estimation of citral-a (geranial), citral-b (neral), total citral, citronellal and geraniol content. The oil recovered from hexane, carbon tetrachloride and ethanol fractions was in the range from 10.0 to 28.2%. Moreover, sum of oil recovered from all fractions was 100 percent which showed that oil sample passed through glass column was recovered completely. In column chromatography experiment, citral-a (geranial), citral-b (neral) and total citral content increased when hexane and carbon tetrachloride were used as eluants. The range of citral-a, citral-b and total citral content was 44.5-48.5%, 25.2-30.5% and 70.0-76.8%, respectively when carbon tetrachloride was taken as eluant which was higher in comparison to the corresponding values (41.5%, 28.6% and 70.1%, respectively) in pure oil sample. In case of hexane as eluant, the range of citral-a, citral-b and total citral content was 42.4-45.3%, 28.1-30.5% and 71.2-75.2%, respectively. However, these constituents decreased significantly when ethanol was taken as eluant and the range of these constituents was 12.1-39.6%, 11.6-26.1% and 23.7-65.7%, respectively. Aqueous extracts of oils recovered from various hexane, carbon tetrachloride and ethanol fractions were found to be effective in controlling root-knot nematodes M. incognita. However, the magnitude of mortality was different for different fractions and some fractions were 100 percent effective even at 1:5 concentration in comparison to 91.5% mortality data of aqueous extract of pure oil sample at same concentration. The variation in magnitude of mortality may be due to different amounts of chemical constituents present in the oils recovered in different fractions. Keeping in view of these studies, it can be inferred that silica gel and aluminium oxide (neutral) as adsorbents and carbon tetrachloride and hexane as eluants play a vital role in improving the quality of lemongrass essential oil.