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101.
柴向华  唐忠盛  王胜利  吴克刚  潘显宗 《安徽农业科学》2012,40(24):12244-12246,12266
[目的]研究各种蛋白酶水解提取香菇可溶性含氮化合物,优化筛选胰蛋白酶酶解条件。[方法]采用各种食品级蛋白酶对香菇进行酶解,选取较优蛋白酶酶解条件,并结合螺杆挤压预处理提取香菇可溶性氮。[结果]胰蛋白酶提取香菇可溶性含氮化合物的最佳酶解条件为料液比1∶11 g/ml,酶解时间1.5 h,酶解温度50℃,酶量0.5%。在最优酶解条件结合螺杆挤压物理方法,可使香菇可溶性氮释放率及氨基态氮含量提高94.94%、82.94%。[结论]研究可为食用菌鲜味物质的提取利用提供参考。  相似文献   
102.
不同品种和年限人参中糖类含量比较研究   总被引:1,自引:0,他引:1  
[目的]检测不同品种和年限人参糖类成分的含量,并分析其分布规律。[方法]采用紫外分光光度法对高丽参、西洋参、林下参和园参的总糖、还原糖和可溶性多糖含量分别进行检测。[结果]不同品种人参总糖含量以林下参最低;还原糖含量以林下参最低,高丽参和园参含量最高;可溶性多糖含量以林下参和高丽参最高。不同年限园参的检测发现,7年生园参的总糖含量明显降低,还原糖含量明显升高。[结论]不同品种人参糖类含量存在差异,且差异与生长环境和加工程序有一定关系;不同年限园参中糖类的含量与其生长年限有关。  相似文献   
103.
大白菜发育过程中可溶性蛋白质的变化   总被引:4,自引:2,他引:4  
通过对3个不同抽薹期类型大白菜品种在不同发育时期体内可溶性蛋白质种类和水平变化的研究,得到:P8(Rf=0.482)和P11(Rf=0.620)出现在植株的花芽分化过程中,而P15(Rf=0.448)和P16(Rf=0.416)出现在花茎分化时期;整个发育时期体内的共同蛋白P5(Rf=0.645)和P6(Rf=0.575)水平在花芽分化开始时达到最大,随后逐渐降低,直至抽薹后又有回升;不同大白菜品种间在发育过程中,其体内可溶性蛋白质无质的区别,在同一发育时期,所有可溶性蛋白水平均表现出大白菜品种夏丰>日清>黄点心的结果  相似文献   
104.
ABSTRACT

The sugar-accumulating potential of global and local sweet and grain sorghum varieties were tested under the local conditions. The basis for this study was the dependency of sugar accumulation on temperature and photoperiod. Thus, the efficacy of cultivars as a bioenergy source would need to be determined based on their performance under the local environmental conditions. A strong correlation of sucrose content with brix was observed, enabling large-scale screening of varieties for high sucrose content. The morphological characteristics inherent in sweet sorghum, such as tall stems, greater number of leaves and a longer vegetative period, were found to correlate with the total stem sugar content. Assessment of sugars along the stem revealed maximum sugar accumulation in the upper intermediate to upper internodes in most of the varieties tested. The maximum theoretical ethanol yield (MTEY), a function of brix and juice yield, was determined as a better indicator of testing the performance of a variety as a potential source of bioethanol, mainly due to a negative correlation of stem juiciness and sucrose content in the varieties tested. Further, the relative expression of vacuolar invertase genes, SbINV1 and SbINV2, was studied, and a strong negative correlation of SbINV2 to stem sucrose content was observed. This reveals a possibility of involvement of vacuolar invertase gene, SbINV2, in sugar accumulation in sweet sorghum stems, and as a key candidate for molecular breeding studies for higher stem sugar content.  相似文献   
105.
Abstract

Digltaria eriantha and Chloris gayana were grown under controlled conditions for three months and were treated with a nutrient solution containing 150 mMol NaCl and the following nitrogen sources: 25 or 200 mg/l NH4 +‐N or NO3 ?‐N or no nitrogen. The application of nitrogen was found to stimulate growth, i.e. leaf area and dry mass in both grasses, with a greatest growth response to both NH4 +—N treatments in D. eriantha, and NH4 +‐N and NO3 ?—N treatments in C. gayana. Proline accumulated in both grasses, but this accumulation followed different trends in the two grasses. Soluble sugars (non‐structural) accumulated in the above ground component in D. eriantha, while in C. gayana soluble sugars accumulated predominantly in the roots, possibly as osmotica, or for storage and may thus have been available for regrowth.  相似文献   
106.
目的 探讨分别以红参、生晒参(相同产地和参龄)为原料的独参汤中主要化学成分含量的差异、为解释传统中药方剂独参汤的选材和功效提供理论基础.方法:分别以红参、生晒参为原料,按照传统的独参汤的煎煮方法,制备红参独参汤和生晒参独参汤;对两种独参汤进行主要有效组分的萃取分离,得到总脂溶性成分、总皂苷和总水溶性多糖;分别通过GC-MS、HPLC和UV测定其测定其总脂类成分、总皂苷及总水溶性多糖的含量.结果红参独参汤中测得了5种脂类成分,生晒参独参汤中测得了8种脂类成分;红参独参汤中的总皂苷含量为1.3%±0.2%,生晒参独参汤中的总皂苷含量为1.1%±0.2%;总皂苷中含量最多的五种单体皂苷的含量分别为:红参独参汤中Rg1:0.1079%、Rc:0.0801%、Re:0.0614%、Rd:0.0397%、Rb 1:0.0988%,生晒参独参汤中Rg1:0.0752%、Rc:0.0518%、Re:0.0352%、Rd:0.0300%、Rb 1:0.0778%;生晒参独参汤中的水溶性多糖含量约为8.76%,红参独参汤中的水溶性多糖含量约为11.75%.结论红参独参汤中的人参皂苷和人参水溶性多糖的含量均多于生晒参独参汤中的含量,两种独参汤中均含有脂类成分.  相似文献   
107.
The objective of this study was to investigate the effects of total dietary fiber level on nutrient digestibility and the relationship between apparent total tract digestibility of total dietary fiber, and soluble dietary fiber, insoluble dietary fiber and available energy. Sugar beet pulp was as the only fiber source. The experiment was designed as a 6 x 6 Latin square with an adaptation period of 7 d followed by a 5-d total collection of feces and urine. Feed intake tended to decrease (P =0.] O) as total dietary fiber level increased. The apparent total tract digestibility of dry matter, crude protein and gross energy decreased (P 〈0.0]) when total dietary fiber increased but the digestibility of soluble dietary fiber and insoluble dietary fiber increased (P 〈0.01). The digestible energy and metabolizable energy content of diets decreased (P 〈0.01) as the total dietary fiber increased.  相似文献   
108.
[目的]研究高温α-淀粉酶和糖化酶对怀山药的分解效果。[方法]利用高温α-淀粉酶和糖化酶对怀山药分步进行水解糖化以减小分散颗粒直径和沉淀率,在控制一定温度和时间的条件下,采用正交设计和因素分析来确定最适酶解条件,从而提高山药汁的可溶性固形物百分含量,降低其沉淀率和色泽。[结果]试验表明,双酶法分解怀山药的最适酶解条件为:高温α-淀粉酶添加量0.4%(20 000U),山药浓度10%,酶解温度85℃,时间2 h条件下酶解效果最佳;糖化酶添加量0.4%(10 000 U),糖化温度55℃,时间3 h,pH 5.0。[结论]研究可为怀山药的深度开发提供一定的理论依据。  相似文献   
109.
Amino sugars, as a kind of microbial residue, are strongly associated with cycling of microbial-derived soil organic matter. However, responses of amino sugars to agricultural practices on the Loess Plateau in North-western China are poorly known. The objective was to evaluate effects of film mulching (no film mulching + NPK fertilizers, CK; film mulching + NPK fertilizers, PF; film mulching + NPK fertilizers + cow manure, FM) on accumulations of amino sugars in this region. FM significantly increased total amino sugar by 190.46 mg kg?1 in 0–10 cm layer and 214.66 mg kg?1 in 10–20 cm layer relative to CK, but PF significantly decreased it by 139.28 mg kg?1 in 0–10 cm layer. Ratios of glucosamine to muramic acid were markedly decreased by 2.50 in 0–10 cm layer and 2.28 in 10–20 cm layer in FM than CK, suggesting a tendency of microbial residues pool shift towards bacterial residues in this agroecosystem. These results indicated film mulching alone was not benefitial to accumulation of amino sugar while organic manure contributed to the build-up of amino sugar partly due to manure contained microbial residues. The different patterns of amino sugars suggested significant changes in the quality of microbial-derived organic matter.  相似文献   
110.
In spite of their low concentrations in soil solutions, low–molecular weight organic substances (LMWOS) such as amino acids, sugars, and uronic acids play a major role in the cycles of C and N in soil. With respect to their low concentrations and to possible matrix interferences, their analysis in soil leachates is a challenging task. We established two HPLC (high‐performance liquid chromatography) methods for the parallel determination of amino acids and carbohydrates in soil leachates. The pre‐column derivatization of amino acids with an o‐phthaldialdehyde (OPA) mercaptoethanol solution yields quantitation limits between 0.03 and 0.44 µmol L–1 and SD values of <8.3% (n = 9). High‐performance anion‐exchange chromatography (HPAEC) on a Dionex CarboPac PA 20 column with a NaOH acetate gradient combined with pulsed amperometric detection (PAD) was used for the determination of carbohydrates. The calibration curves obtained for 11 carbohydrates showed excellent linearity over the concentration range from 0.02 to 50.0 mg L–1. Recovery studies revealed good results for all analytes (89%–108%). Interferences from Hg(II) salts and chloroform used for stabilization of the leachates did not occur with both chromatographic methods. The optimized method was successfully used for quantitative determinations of amino acids and carbohydrates in soil leachates.  相似文献   
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