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BACKGROUND: Two Ocimum basilicum cultivars, ‘Vikarsudha’ and ‘CIM‐Saumya’, grown in the Kumaon region of western Himalaya were evaluated for their essential oil yield and composition at different stages of plant growth during two distinct cropping seasons (spring–summer and rain–autumn). RESULTS: The highest yield of essential oil was obtained at full bloom stage in both cultivars in both cropping seasons. The essential oils obtained from different stages in two cropping seasons were analysed by capillary gas chromatography with flame ionisation detection, and gas chromatography–mass spectrometry. The major component of cultivar ‘Vikarsudha’ was methyl chavicol (84.3–94.3%), while for cultivar ‘CIM‐Saumya’ the main components were methyl chavicol (62.5–77.6%) and linalool (14.4–34.1%). CONCLUSION: This study clearly indicated that cultivar, cropping season, plant ontogeny and plant part had significant effects on the yield and quality of the essential oil of O. basilicum. Further, the amount of methyl chavicol in the cultivars grown in this region was higher than in cultivars from other parts of India. Copyright © 2011 Society of Chemical Industry  相似文献   
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Ultrafiltration (UF) of coconut oil was carried out using a Millipore membrane cell at different pressures (0.1–0.4 MPa) and with different molecular weight cutoff membranes, that is,YM-1 (1 kDa), YM-3 (3 kDa), YM-10 (10 kDa), YM-30 (30 kDa), and PLTK-30 (30 kDa). Reduction of free fatty acids (FFAs) was 93.6%, 92.7%, 83.5%, 82.6%, and 81.6% with ethanol, methanol, acetone, n-propanol, and isopropyl alcohol, respectively, in three-stage filtration. The effects of temperature and applied pressure on the permeate flux and oil rejection were also studied with membranes using multistage filtration. As pressure increased from 0.1 to 0.4 MPa, the permeate flux and oil rejection increased linearly. A significant reduction of FFA was observed, which is in proportional with the amount of solvent in the feed used. The oil loss was less at lower temperature (25 °C) and pressure (0.2 MPa). Using PLTK 30 membrane with three-stage filtration, reduction of FFA was achieved up to 93% and 94% with methanol and ethanol solvents, respectively.  相似文献   
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Choroidal neovascular membrane in Best's vitelliform macular dystrophy   总被引:2,自引:0,他引:2  
The right eye of a 9-year-old white boy with Best's vitelliform macular dystrophy had an intact egg-yolk lesion and a retinal pigment epithelial defect superiorly, suggesting an early pseudohypopyon stage. The disruptive phase of the left eye showed subretinal hemorrhages, a "signet ring," and a subretinal neovascular membrane.  相似文献   
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This study investigated the effect of sequential extraction techniques and pretreatment methods in enhancing the recovery of high-value products from spent coffee ground. Supercritical carbon dioxide (SC-CO2) deoiling was performed to recover non-polar lipids, and subcritical water (SCW) hydrolysis of deoiled spent coffee ground (SCG) was conducted involving pretreatment with ultrasound (US-SCG), and sample particle size reduction (PS-SCG). SCW temperature, solid/liquid mixing ratio, constant pressure and residence time were studied for their effect on extracting reducing sugars (RS), total phenolic content (TPC), total flavonoid content (TFC), 5-HMF, and furfural. Temperature increase enhanced hydrolysis efficiency and promoted RS dehydration into 5-HMF and furfural. At 180 °C and 40 mg/600 mL, TPC, TFC and RS values increased significantly with ultrasound pretreatment correlating with improved antioxidant activities by DPPH and ABTS assays. Highest amount of 5-HMF and furfural was obtained at 210°C (highest temperature studied) with 44.71 and 2.36 mg/100 g. Chlorogenic acid recovery was the highest in the non-deoiled SCG (15.07 mg/100 g), with no significant difference observed in PS-SCG, suggesting an increase due to its reduced particle size. The results of this study provide comprehensive knowledge on the combined effects of integrated engineering systems to boost the valorisation of SCGs into high-value products.  相似文献   
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The antioxidant capacity of commonly consumed cucurbits vegetable was determined by the DPPH, FRAP, Fe3+ reducing power, and hydrogen peroxide scavenging assay. The aqueous extract of Luffa cylindrica showed the highest value of phenolic content and antioxidant capacity based on FRAP, Fe3+ reducing power, and hydrogen peroxide scavenging assay. However, Laginaria siceraria extract showed the highest flavonoid and DPPH scavenging activities among all three cucurbits used in this study. Phenolic content in aqueous extracts of Luffa cylindrica and Laginaria siceraria was almost equal. Cucurbita maxima exhibited the lowest phenolic, flavonoid content, and exhibited the lowest power of antioxidant scavenging. The antioxidant capacity of cucurbits was significantly correlated (P < 0.05) with the phenolic content of their extracts. The antioxidant capacity of Luffa cylindrica and Laginaria siceraria have also shown a significant correlation (P < 0.05).  相似文献   
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In the present study, application of different levels (0, 1 and 2%) of citric acid treated sweet potato starch as a fat replacer (FR) in a high (11% fat), medium (6% fat) and low-fat (1%) ice creams were investigated. Results indicated that hardness value tends to improve with the addition of 1% FR in all reduced fat ice creams. During 60 days of storage, a decreasing trend was noticed in overrun, acidity and hardness values of ice cream samples. Overall score of sensory conveyed that the reduced fat ice creams with 1% FR (medium fat ice cream and low fat ice cream) were found to be very acceptable by sensory panels with a similar physicochemical characteristics and acceptance as high-fat ice cream (control) at the end of storage period. Citric acid treated sweet potato starch proved to be a promising alternative as a fat replacer in the ice cream production.  相似文献   
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