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综述了烟草成分中的葡萄糖对烟气的影响,葡萄糖酯、苷衍生物的合成及其与烟气品质的关系,对葡萄糖的化学修饰在烟草工业中的应用前景进行了展望。 相似文献
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为开发特色烟用香原料,针对葡萄糖/脯氨酸Maillard反应模型体系,通过正交试验考察了反应时间、反应温度、体系pH和溶刹中乙醇体积分数对产物的紫外可见吸收、挥发性成分及烟草加香效果的影响,确定了适宜的反应条件。结果表明:各因素对产物紫外可见l吸收的影响大小依次为pH〉反应时间〉反应温度〉乙醇体积分数;GC—MS鉴定出33种挥发性成分,多种成分对香气有重要贡献;感官评价表明反应温度105℃、反应时间4h、pH10、乙醇体积分数40%的条件下生成的产物具有良好的烟草加香效果,香气量、香气质较好,杂气、刺激性小。研究表明,葡萄糖/脯氨酸Maillard反应产物具有良好的烟草加香应用价值。 相似文献
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苯氧乙酸类四乙酰葡萄糖酯的合成及其生理活性的探索 总被引:7,自引:2,他引:5
以苯氧乙酸类化合物为母体,合成了17个取代苯氧乙酸四乙酰葡萄糖酯的化合物。采用相转移催化合成方法,反应产和的较单一,易纯化。通过元素分析、IR及^1HNMR,MS确证了化合物的结构,对其中某些化合物做了水稻种子育苗试验。结果表明,化合物有一定的生物活性。 相似文献
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利用酶促方法合成阿魏酸葡糖酯,对酶和有机溶剂进行了比较和筛选,并对影响阿魏酸葡糖酯产率的因素(酶量、反应时间、反应温度、底物比)进行了研究。结果表明,葡萄糖和阿魏酸乙烯酯(摩尔比4∶1)分别加入到体积比2∶1的无水吡啶和叔丁醇中,20 g/L Novozym 435脂肪酶,在220 r/min的空气振荡器中50℃反应72 h,产率能达到80.9%。 相似文献
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本文概述了脂肪酶催化制备甘油单酸醌的优点及三条合成路线,介绍了酶促法所用的脂肪酶,并着重讨论了温度及甘油中水分一对产率的影响。 相似文献
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以二环己基碳二亚胺(DCC)为缩水剂,在4-二甲氨基吡啶(4-DMAP)催化下合成了化合物1,2-O-异丙叉基-3-O-异戊酰基-5-O-肉桂酰基-α-D-呋喃木糖,其结构经IR、1HNMR、13CNMR和HRMS验证。采用热裂解-GC-MS对该化合物的热裂解产物进行分离鉴定,并初步进行了卷烟加香实验。结果表明,温度对合成产物的热裂解产物种类和含量有较大影响,主要有呋喃衍生物、月桂烯、异戊酸等;合成产物的质量分数为0.02%~0.03%时与烟香谐调,可以改善卷烟香气质,增加香气量,降低刺激性,改善余味。 相似文献
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在相转移催化剂四丁基碘化铵的作用下.溴代乙酰基葡萄糖与取代苯甲酸反应合成了6个取代苯甲酸葡萄糖酯.所合成的糖酯的结构经IR、^1HNMR、元素分析确证。通过对糖酯化合物的^1HNMR图谱中糖环C1位质子的化学位移及偶合常数.并结合红外图谱中糖环C1H的弯曲振动吸收,确证糖酯化合物均为β型异构体。 相似文献
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Linqiu Cao Uwe T. Bornscheuer Rolf D. Schmid 《European Journal of Lipid Science and Technology》1996,98(10):332-335
Lipase-catalyzed synthesis of sugar fatty acid esters was performed in a heterogeneous reaction system in the presence of an organic solvent serving as adjuvant. Although the sugar is almost insoluble in such a system, high conversions to the corresponding sugar esters were achieved, due to crystallization of the product. Acylation occurred regioselectively at the primary hydroxyl group and subsequent diacylation was observed only in the case of caprylic acid (2–5%). Best conditions were found for solvents having low log P values and low product solubility such as acetone, using immobilized lipase from Candida antarctica (CAL-B, Novo SP435) and fatty acids with chain lengths from C12 to C8 as acyl donors. The esterification of β-D(+)-glucose with stearic acid resulted in up to 100% conversion after 48 hours equal to a productivity of 0.4 mmol sugar ester per gram lipase and hour. 相似文献
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非水相中脂肪酶转化失水山梨醇单油酸酯反应的研究 总被引:2,自引:0,他引:2
失水山梨醇单油酸酯可通过脂肪酶CAL在无溶剂体系中转化合成。对反应体系进行条件优化后,进行了10批酶法合成失水山梨醇单油酸酯。结果表明该酶具有较高的催化活性和稳定性,每批转化率均达92%以上,10批反应结束,酶活性仍有约70%,半衰期为921.4h。但单酯含量逐批略有下降,从最初85.3%降至约56.6%,与化学合成的产品比较,各项指标基本接近,但酶法合成的产品前5批单酯含量较高,均可达70%以上。 相似文献
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以顺6-壬烯醇和2, 3-吡嗪-二甲酸为原料,以环己基碳二亚胺(DCC)为缩水剂,在4-二甲氨基吡啶(DMAP)催化作用下,合成了2, 3-吡嗪-二甲酸二顺6-壬烯酯。其结构经IR, 1H NMR, 13C NMR, HRMS图谱对比得到验证,并对其进行了热裂解和卷烟加香实验。结果表明:(1)合成产物为目标产物;(2)裂解温度对合成产物的热裂解产物的种类和含量有较大影响,随着裂解温度的升高,裂解程度愈来愈剧烈;(3)目标产物在卷烟中的适宜用量为0.01%,目标产物加入到卷烟中后能够明显改善卷烟的吸食品质,协调烟香,减少刺激性和杂气,改善余味。 相似文献
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以顺-6-壬烯醇和2,3-吡嗪-二甲酸为原料,以环己基碳二亚胺(DCC)为缩水剂,在4-二甲氨基吡啶(DMAP)催化作用下,合成了2,3-吡嗪-二甲酸二顺-6-壬烯酯。其结构经IR,1HNMR,13CNMR,HRMS图谱对比得到验证,并对其进行了热裂解和卷烟加香实验。结果表明:(1)合成产物为目标产物;(2)裂解温度对合成产物的热裂解产物的种类和含量有较大影响,随着裂解温度的升高,裂解程度愈来愈剧烈;(3)目标产物在卷烟中的适宜添加量为0.01%,目标产物加入到卷烟中后能够明显改善卷烟的吸食品质,协调烟香,减少刺激性和杂气,改善余味。 相似文献
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Ghanwa Afach Yasuhiro Kawanami Nopparat Cheetangdee Kazuhiro Fukada Ken Izumori 《Journal of the American Oil Chemists' Society》2008,85(8):755-760
The diesterification of d-psicose (the C-3 epimer of d-fructose) with fatty acid vinyl esters of selected acyl chain lengths (C8, C10, and C12) was successfully carried out using Candida antarctica lipase (Novozym 435) at 45 °C for 24 h to give the 1,6-diacyl-d-psicofuranoses with a high regioselectivity in good yields (83–90%). These diesters of d-psicose have hydrophilic-lipophilic balance (HLB) values (6.5–8.2) similar to HLB values of monoglyceride compounds which
constitute the largest single type of emulsifiers employed by the food industry. Ability of the d-psicose diesters to stabilize oil-in-water emulsions and the weight-averaged oil-droplet diameter in the emulsions was evaluated
in this study. Emulsion stability of oil droplets stabilized by d-psicose dicaprylate (0.3%, w/v in oil phase) was comparable to d-fructose dicaprylate (0.2%, w/v). It was further confirmed that the d-psicose diesters exhibited an emulsification activity depending on the chain length of fatty acid; d-psicose dicaprate showed better emulsion stability than the other diesters. 相似文献
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Ran Ye Sang-Hyun Pyo Douglas G. Hayes 《Journal of the American Oil Chemists' Society》2010,87(3):281-293
Saccharide–fatty acid esters, important biobased and biodegradable emulsifiers in foods, cosmetics, and pharmaceuticals, were
produced with high yields and productivity via immobilized Rhizomucor miehei lipase-catalyzed esterification in solvent-free systems at 65 °C. Preliminary experiments demonstrated high rates of reaction
occurred in the presence of acetone near or above its boiling point, due to the formation of 10–200 μm suspensions of saccharide
particles. Subsequently, a two-step process was developed to produce a solvent-free supersaturated solution of 1.5–2.0 wt%
saccharide that remained stable for ≥10–12 h. The solvent-free suspensions were used in a bioreactor system at 65 °C, consisting
of a reservoir open to the atmosphere that contained molecular sieves, a peristaltic pump, and a packed bed bioreactor, operated
under continuous recirculation. At 10 h intervals, suspensions were re-formed by treating the substrate/product mixture with
additional acyl acceptor and applying strong agitation. Using this system and approach, a product mixture containing 88% fructose
oleate was formed, of which 92% was monoester, within 6 days. This equates to a productivity of 0.2 mmol h−1 g−1, which is similar to values reported for synthesis in the presence of solvent. 相似文献
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