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Ester Content (ester + content)
Selected AbstractsVariation in essential oil composition of rose-scented geranium (Pelargonium sp.) distilled by different distillation techniques,FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005Kiran G. D. Babu Abstract The rose-scented geranium (Pelargonium sp.) cultivar ,Kelkar', grown in the agroclimatic conditions of the western Himalayas, was processed by various hydrodistillation methods, which revealed that water distillation of the herb gave a higher oil yield (0.16,0.22%) than the water,steam distillation (0.09,0.12%) and steam distillation methods (0.06,0.18%). The samples were analysed by GC and GC,MS to study and compare the essential oil compositions which revealed that the oil distilled by the water,steam distillation method contained a higher content of monoterpene hydrocarbons (1.7%), followed by steam distillation without cohobation and without recycling (1.5%). A higher content of sesquiterpene hydrocarbons (4.4%) was found in cumulative oil followed by ,direct oil' (4.2%) obtained by steam distillation with cohobation and without recycling of hydrosol, followed by the water,steam distillation method (3.4%). ,Decanted oil', recovered from redistilling the hydrosol obtained by steam distillation with cohobation and without recycling, contained maximum monoterpene cyclic ethers (1.1%) and carbonyl content (9.9%), closely followed by water,steam distillation method (1.1% and 7.2%, respectively). Steam distillation without cohobation and without recycling of hydrosol yielded essential oil with a higher percentage of esters (21.1%), followed by ,direct oil' (16.6%). Lower ester content (5.3%) was noticed in ,decanted oil', followed by oil distilled by steam distillation with cohobation and with recycling (11.8%) and oil distilled in a Clevenger apparatus by the water distillation method (12.2%), whereas maximum total alcohols were found in the ,decanted oil' (75.1%), followed by oil from the Clevenger apparatus (72.8%) and steam distillation with cohobation and with recycling (69.1%). A lower alcohol content was found in the ,direct oil' (55.2%) closely followed by ,cumulative oil' (55.8%). The variation in total alcohol and ester contents in geranium oil samples, distilled by using different processing techniques on pilot scale distillation, is mainly due to hydrolysis of some volatile constituents. This was further supported by acid values of the oils, along with other physicochemical properties, such as speci,c gravity, optical rotation, refractive index, solubility in alcohol, ester value with cold and hot methods, estimation of ester content as geranyl formate and geranyl tiglate, ester number after acetylation, and ester number after formylation with aceto-formic acid and formic acid. Methods have been standardized and proposed for distillations of speci,c quality, e.g. ester-rich and alcohol-rich geranium oils, to meet different requirements of the industry. Copyright © 2004 John Wiley & Sons, Ltd. [source] Skin surface lipids and skin and hair coat condition in dogs fed increased total fat diets containing polyunsaturated fatty acidsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 4 2009N. A. Kirby Summary It is generally believed that diets containing increased amounts of polyunsaturated fatty acids (PUFA) result in improved canine skin and hair coat (SHC). However, the extent to which dietary fat amount and type play a role remains to be systematically investigated. The objective of this study was to investigate the role of both increased dietary fat amount and type on SHC assessments of dogs. Improvements of SHC conditions were investigated after feeding three diets containing increased total dietary fat (i.e. 13% total fat) for 12 weeks in relation to a lower fat acclimation diet (i.e. 9% total fat). The higher fat diets varied in polyunsaturated and saturated fat types and amounts but total fat was kept constant. Skin and hair coat assessments were performed at selected intervals by a trained group of veterinarians and graduate students. In addition, hair lipids were fractionated by thin layer chromatography after extraction of plucked hair samples. Significant improvements were found in hair coat glossiness and softness in all dogs fed the higher fat diets in relation to the acclimation diet. Improvements as a result of fat type were also seen but only at 12 weeks. A parallel finding was a marked increase in hair cholesteryl ester content determined at the end of the study at which time SHC scores were significantly improved. Skin and hair coat condition improvements may thus be related to increased cholesteryl ester deposited on the hair shaft surface when high fat diets are fed. Whereas this finding is preliminary, hair lipid analysis may be a useful, non-invasive technique with which to help assess dietary effects on canine SHC. [source] Exendin-4 regulates pancreatic ABCA1 transcription via CaMKK/CaMKIV pathwayJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 5 2010Junhua Li Abstract ATP-binding cassette transporter A1 (ABCA1) in pancreatic , cells influences insulin secretion and glucose homeostasis. This study investigates whether the long-acting agonist of the glucagon-like peptide 1, namely exendin-4, which mediates stimulatory effects on ABCA1 gene expression, could interfere with the Ca2+/calmodulin (CaM)-dependent protein kinase (CaMK) cascade. ABCA1 promoter activity was examined by reporter gene assay in rat insulin-secreting INS-1 cells incubated with exendin-4. CaMKIV activity was assessed by detection of activation-loop phosphorylation (Thr196) of CaMKIV. We investigated the influence of the constitutively active form (CaMKIVc) or CaMKIV knockdown on ABCA1 expression. Increased abundance of ABCA1 protein was noted in response to rising concentrations of exendin-4 with maximum induction at 10 nM. Exendin-4 also stimulated ABCA1 promoter activity, but failed to do so in the presence of STO-609, a CaMKK inhibitor. Up-regulation of CaMKIV phosphorylation (at Thr196) peaked after 10 min. of exposure to exendin-4. CaMKIVc enhanced or up-regulated ABCA1 promoter activity in INS-1 cells. Furthermore, exendin-4 induction of ABCA1 protein expression was significantly suppressed in cells treated with CaMKIV-siRNA. Activation of the CaMKK/CaMKIV cascade by exendin-4 stimulated ABCA1 gene transcription, indicating that exendin-4 plays an important role in insulin secretion and cholesterol ester content in pancreatic , cells. [source] Sensory, Flavor, and Microbial Analyses of Raw, Pasteurized, and Irradiated Apple CidersJOURNAL OF FOOD SCIENCE, Issue 2 2005Fransiska Yulianti ABSTRACT: Ten trained descriptive panelists evaluated the sensory characteristics of raw, pasteurized, and irradiated apple cider, with and without sorbate. For the main effect of processing treatments, raw, pasteurized, and irradiated ciders were not different from each other in sweetness, sourness, astringency, and caramelized flavor. Irradiated cider had less apple flavor and lower ester content than raw cider. For the main effect of sorbate, the addition of sorbate (0.05%) increased sweetness. Irradiated cider had higher musty flavor than both raw and pasteurized ciders, and the addition of sorbate to irradiated cider further increased musty flavor. The addition of potassium sorbate to apple cider effectively reduced yeast and aerobic bacteria counts and minimized the degradation of several esters during irradiation. [source] Synthesis and liquid crystalline properties of new amide-modified poly(1,4-cyclohexanedimethylene terephthalate),JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 1 2006P. Deepa Abstract New series of cycloaliphatic poly(ester-amide)s, poly(1,4-cyclohexanedimethyleneterephthalate- co -1,3-cyclohexanedimethylene terephthalamide), were synthesized through solution polymerization route. The compositions of ester/amide units in the copolymers were varied from 0 to 100% by varying the amount of 1,4-cyclohexanedimethanol and 1,3-cyclohexanebis(methylamine) in the feed. The structures of the polymers were confirmed by NMR and FTIR, and the molecular weights were determined by inherent viscosity. The composition analysis by NMR reveals that the reactivity of the diamine toward the acid chlorides is lowered than that of diol, which results in the formation of more ester content in the poly (ester-amides). The thermal analysis indicate that the new poly(ester-amide)s having less than 10 mol % of amide linkages are thermotropic liquid crystalline from 200 to 250 °C and a thread like nematic phases are observed under the polarizing microscope. WXRD studies suggest that the liquid crystalline domains promote the nucleation process in the polyester chains and increases the percent crystallinity of the poly(ester-amide)s. The glass transition temperature of the copolymers initially increases with increase in amide units because of the presence of nematic phases and subsequently follows the Flory,Fox behavior. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 42,52, 2006 [source] Variation in essential oil composition of rose-scented geranium (Pelargonium sp.) distilled by different distillation techniques,FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005Kiran G. D. Babu Abstract The rose-scented geranium (Pelargonium sp.) cultivar ,Kelkar', grown in the agroclimatic conditions of the western Himalayas, was processed by various hydrodistillation methods, which revealed that water distillation of the herb gave a higher oil yield (0.16,0.22%) than the water,steam distillation (0.09,0.12%) and steam distillation methods (0.06,0.18%). The samples were analysed by GC and GC,MS to study and compare the essential oil compositions which revealed that the oil distilled by the water,steam distillation method contained a higher content of monoterpene hydrocarbons (1.7%), followed by steam distillation without cohobation and without recycling (1.5%). A higher content of sesquiterpene hydrocarbons (4.4%) was found in cumulative oil followed by ,direct oil' (4.2%) obtained by steam distillation with cohobation and without recycling of hydrosol, followed by the water,steam distillation method (3.4%). ,Decanted oil', recovered from redistilling the hydrosol obtained by steam distillation with cohobation and without recycling, contained maximum monoterpene cyclic ethers (1.1%) and carbonyl content (9.9%), closely followed by water,steam distillation method (1.1% and 7.2%, respectively). Steam distillation without cohobation and without recycling of hydrosol yielded essential oil with a higher percentage of esters (21.1%), followed by ,direct oil' (16.6%). Lower ester content (5.3%) was noticed in ,decanted oil', followed by oil distilled by steam distillation with cohobation and with recycling (11.8%) and oil distilled in a Clevenger apparatus by the water distillation method (12.2%), whereas maximum total alcohols were found in the ,decanted oil' (75.1%), followed by oil from the Clevenger apparatus (72.8%) and steam distillation with cohobation and with recycling (69.1%). A lower alcohol content was found in the ,direct oil' (55.2%) closely followed by ,cumulative oil' (55.8%). The variation in total alcohol and ester contents in geranium oil samples, distilled by using different processing techniques on pilot scale distillation, is mainly due to hydrolysis of some volatile constituents. This was further supported by acid values of the oils, along with other physicochemical properties, such as speci,c gravity, optical rotation, refractive index, solubility in alcohol, ester value with cold and hot methods, estimation of ester content as geranyl formate and geranyl tiglate, ester number after acetylation, and ester number after formylation with aceto-formic acid and formic acid. Methods have been standardized and proposed for distillations of speci,c quality, e.g. ester-rich and alcohol-rich geranium oils, to meet different requirements of the industry. Copyright © 2004 John Wiley & Sons, Ltd. [source] | ||||||||||