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Bixa orellana L. seeds possess a resinous lipid (6.3 %), which has a pungent and spicy odour. The seed is known for its medicinal properties such as anti‐inflammatory, antipyretic activity and as a cure for tonsilitis. Trachyspermum copticum L. seed is a well known digestive aid and relief from colic pain. T. copticum possesses essential oil rich in thymol (>50 %) and lipid (15.6 %). The present study was aimed to quantify lipid classes of these two species by silicic acid chromatography and analyze their fatty acid composition by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). It was observed that the seed lipids are rich in neutral lipids with 98.1 and 95.2 % and lower quantities of glycolipids of 1.5 and 3.8 % and phospholipids of 0.36 and 1.0 % in B. orellana and T. copticum, respectively. The fatty acid composition of B. orellana seed lipid showed major quantities of palmitic (26.9 %), linoleic (26.1 %), oleic (17.5 %), linolenic (15.1 %), stearic acid (10.8 %) and small quantities of eicosanoic acid (3.6 %). In T. copticum seed lipids, petroselinic acid (68.3 %) and linoleic acid (25.3 %) together constituted 93 % of the total lipid. The results revealed that the lipids after recovery of the essential components namely, bixin and volatile oil from B. orellana and T. copticum, respectively can be further explored for industrial applications.  相似文献   
3.
A simple chemoenzymatic method was developed for the preparation of epoxy lecithin that contains epoxy oils and phospholipids. The parameters such as lipase concentration, hydrogen peroxide concentration, and time of the reaction were studied. The product was evaluated as a plasticizer in polyester laminates and compared with virgin polyester laminates. The laminates were prepared using various amounts of epoxy lecithin and evaluated for different properties. The epoxy lecithin modified laminates showed good impact strength, tensile, and chemical resistance properties. These laminates were also evaluated for vicat softening point and water absorption. The epoxy lecithin can be used as a plasticizer in polyester laminates. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
4.
The present study involved the synthesis and antimicrobial evaluation of alkyloxy propanol amine-based cationic lipids N,N-dimethyl-1-octadecylamino-3-alkyloxy-2-propanol (series A, 7a–e) and N-methyl-N,N-di-(2-hydroxy-3-alkyloxy-2 propyl) octadecylamine (series B, 9a–e) and their acetylated derivatives (8a–e and 10a–e). A simple three-step chemo-enzymatic approach was employed for the synthesis of 7a–e and 9a–e in 71–80 and 67–88 % yields, respectively. The first step involved the synthesis of a series of glycidyl ethers from a series of alcohols (C4, C8, C10, C12, C14) which were opened in the second step with octadecylamine to obtain 1-octadecylamino-3-alkyloxy-2 propanol (5a–e) and N,N-di-(2-hydroxy-3-alkyloxypropyl) octadecylamine (6a–e). In the third step, alkyloxy propanolamines (5a–e, 6a–e) were quaternized using methyl iodide to yield quaternized ammonium salts. The quaternized ammonium salts were enzymatically acetylated using Candida antarctica lipase-B based immobilized enzyme Novozym 435 to obtain their acetylated derivatives. The quaternized salts as well as their acetylated derivatives were evaluated for antibacterial and antifungal properties. The title compounds were found to possess moderate to good antibacterial activities against all the studied bacterial strains namely, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella aerogenes compared to streptomycin and cetyl trimethyl ammonium bromide (CTAB). The title compounds exhibited relatively good antifungal activities against Candida albicans and no significant activities against other fungal strains namely, Saccharomyces cerevisiae, Rhizopus oryzae and Aspergillus niger when compared to amphotericin B and CTAB.  相似文献   
5.
An efficient and simple lipase-mediated synthesis of alkyl ricinoleates and 12-hydroxy stearates was performed by transesterification of methyl ricinoleate/12-hydroxy stearate and various alcohols in a solvent-free system without estolide formation. The reaction conditions were optimized by varying the temperature, pressure, and dosage of lipase. Sulfates of alkyl ricinoleates/12-hydroxy stearates were evaluated for surfactant properties such as surface tension, critical micelle concentration, emulsifying properties, foaming power, and calcium tolerance. The surfactant properties of sulfated alkyl ricinoleates were found to be superior to the sulfated alkyl 12-hydroxy series. The surfactant properties of the above two series of compounds were then compared with sodium dodecyl sulfate, and the properties of sulfated dodecyl ricinoleate and sulfated dodecyl 12-hydroxy stearate were found to be comparable with sodium dodecyl sulfate.  相似文献   
6.
An extensive study has been made on the mineral element compositions of spinach leaves and stems. Twenty two locally grown different spinach samples have been analysed for 16 elements using ICP and atomic absorption spectrophotometric techniques. Both spinach leaves and stems were analysed separately. A detailed elucidation of the inorganic matrix in spinach leaves and stems has been provided. © 1998 SCI.  相似文献   
7.
Hydrogel-based alumina (Al2O3) inks were prepared using Pluronic F-127 with 65 wt% of solid loading (Al2O3). The Al2O3 inks were deposited, and the freestanding samples were studied using TGA/DTA. Significant weight loss was observed between 180 and 360°C. A two-stage hydrogel debinding process of Al2O3 samples was carried out at 180 and 360°C with holding times of 30, 60, 90, 120, and 150 min. The Al2O3 samples were then sintered at 1600°C. X-ray diffraction was used for the phase analysis of the alumina inks, and a scanning electron microscope was used microstructural analysis. Based on the TGA/DTA analysis, a two-stage debinding process was adopted. Significant effect of hydrogel debinding temperature was observed on the sintering and densification behavior of alumina. It was observed that the porosities in the alumina samples were increasing when the debinding time was increased from 30 to 150 min, with the debinding temperature at 180 and 360°C. Moreover, the nature of the porosities was changing from closed porosities to interconnected porosities.  相似文献   
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Grain formation is one of the critical attributes affecting consumer acceptability of ghee. It was observed that both control ghee and low‐cholesterol ghee had grains of 0.236 ± 0.006 and 0.250 ± 0.002 mm size after incubation at 29 °C for 24 h, respectively. The maximum grain yield was 63 ± 2.60% and 68 ± 1.15% at 26 °C in control and low‐cholesterol ghee, respectively. Ghee grains in both the cases were stable over a temperature range of 25° to 36 °C. Time taken by both the samples for onset of nucleation was 50 min. The study revealed that cholesterol removal did not affect the crystallisation behaviour.  相似文献   
10.
Acetylation of lecithin improves the fluid properties, water dispersibility and emulsifying properties of a variety of food formulations. Acetylation of lecithin is usually carried out chemically using acetic anhydride in the presence of tertiary amine. In the present study acetylation of soybean lecithin and egg yolk lecithin was carried out using lipozyme IM 20 having 1,3-specificity from Mucor miehei and vinyl acetate at 70–75 °C. Vinyl acetate played a dual role as acetylating agent and also as the solvent medium. This method selectively acetylated phosphatidylethanolamine without effecting phosphatidylinositol since the enzyme employed was 1,3-specific.  相似文献   
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