The objective of this study was to fractionate lotus seed resistant starch (LRS3) and investigate their structural properties and prebiotic activities. Two main fractions of resistant starch precipitated gradually by ethanol at concentrations of 20% and 30% were named as LRS3-20% and LRS3-30%, respectively. The swelling power and solubility of LRS3-20% were smaller compared to LRS3-30%, and their moisture and resistant starch contents were not significantly different. LRS3-20% and LRS3-30% had molecular weights mainly of 2.0x10(4)-4.0x10(4) and 1.0x10(4)-2.0x10(4) g/mol. Layered strips and gully shapes were evident on the rough surfaces of LRS320%, while LRS3-30% displayed a relatively smooth surface. Both LRS3-20% and LRS3-30% had a B-type crystalline structure with LRS3-20% containing more ordered structures and double-helices. Furthermore, LRS3-20% displayed higher prebiotic activities against Bifidobacterium adolescentis and Lactobacillus acidophilus compared to LRS3-30% and high amylose maize starch. This effect was related to its rough surface and double helix structure.

The aim of this study was to investigate the proliferation effect of fractionated lotus seed resistant starch (LRS3-20%, LRS3-30%) and the structural changes following fermentation. Fractionated lotus seed resistant starch, especially LRS3-20%, promoted the proliferation of these probiotics, and Bifidobacterium longum produced large quantities of acetic acid, while Lactobacillus delbrueckii subsp. bulgaricus produced lactic acid. Additionally, the probiotics with lotus seed resistant starch (LRS3) and LRS3-20% survived more successfully in simulated gastrointestinal solutions compared to glucose, LRS3-30% and high amylose maize starch, but LRS3 and LRS3-20% differed in their abilities to enhance the tolerance to acidic buffer, bile acid and simulated gastric juice. Furthermore, after fermentation, fractionated lotus seed resistant starch displayed a loose, rough surface. The crystalline and double helical structure increased as the amount of amorphous and sub-crystalline structure reduced following fermentation. Interestingly, structural changes were correlated with the original structures and utilisation by the probiotics.

Lotus seed resistant starch, known as resistant starch type 3 (LRS3), was orally administered to mice to investigate its effects on the gut microbiota, short-chain fatty acids (SCFAs) production, and mineral absorption. The results showed that mice fed LRS3 displayed a lower level of gut bacterial diversity than other groups. The numbers of starch-utilizing and butyrate-producing bacteria, such as Lactobacillus and Bifidobacterium and Lachnospiraceae, Ruminococcaceae, and Clostridium, respectively, in mice increased after the administration of medium and high doses of LRS3, while those of Rikenellaceae and Porphyromonadaceae decreased. Furthermore, SCFAs and lactic acid in mice feces were affected by LRS3, and lactate was fermented to butyrate by gut microbiota. LRS3 enhanced the intestinal absorption of calcium, magnesium, and iron, and this was dependent on the type and concentration of SCFAs, especially butyrate. Thus, LRS3 promoted the production of SCFAs and mineral absorption by regulating gut microbiota in mice.

为提高青春双歧杆菌培养基的菌体数量,添加莲子低聚糖作为培养基的单一碳源,采用部分因子设计法确定培养基中对菌体干质量影响较大的因子,快速登高法逼近最大响应区域.在此基础上,利用中心旋转组合设计法进行响应面优化,通过SAS软件回归分析确定培养基各营养成分的最佳质量浓度.研究结果表明:影响青春双歧杆菌生长的培养基主要因子依次为莲子低聚糖、胰蛋白胨和pH值.添加莲子低聚糖后,青春双歧杆菌增菌培养基的最佳发酵条件为:大豆蛋白胨5 g/L,莲子低聚糖7.91 g/L,胰蛋白胨3.66 g/L,酵母粉10 g/L,吐温-80 1 mL,L-半胱氨酸盐酸盐0.5 g/L,无机盐溶液40 mL,pH 7.04.优化后,培养基中短链脂肪酸含量显著提高,菌体干质量达到4.722 g/L,活菌数为(2.92±0.13)×109 CFU/mL.

UNLABELLED:The objective of this study was to investigate the multiple relations between the preliminary molecular structural characteristics and antioxidant activities of polysaccharides from Canarium album (Lour.) Raeusch (CPS). Three polysaccharide fractions, CPS1, CPS2, and CPS3, were isolated from CPS by column chromatography. CPS1 and CPS3 were mainly composed of neutral polysaccharides linked by α- and β-glycosidic linkages while CPS2 was pectin polysaccharides mainly linked by β-glycosidic linkages. According to the SEC-MALLS-RI system, the molecular weight of CPS1 was greater compared to CPS2 and CPS3, and the molecular weight and radius of CPS did not display positive correlation. The chain conformation analysis indicated CPS1 and CPS2 were typical highly branched polysaccharides while CPS3 existed as a globular shape in aqueous. Furthermore, the antioxidant activity of CPS2 was better than that of CPS3, while that of CPS1 was the weakest. The antioxidant activities of polysaccharide fractions were affected by their monosaccharide composition, glycosidic linkage, molecular weight, and chain conformation. This functional property was a result of a combination of multiple molecular structural factors. CPS2 was the major antioxidant component of CPS and it could be exploited as a valued antioxidant product.PRACTICAL APPLICATION:The molecular structural characteristics, antioxidant activities, and structure-function relationships of polysaccharide fractions from Canarium album were first investigated in this study. The results provided background and practical knowledge for the deep-processed products of C. album with high added value. CPS2 was the major antioxidant component of CPS, which could be exploited as a valued antioxidant ingredient in food and pharmaceutical industries.

The objective of this study was to use ultrasonic-microwave synergistic extraction (UMSE) to maximize the yield of polysaccharides from Fortunella margarita (FMPS) and investigate their molecular weight distribution. The results showed the optimum conditions were as follows: ultrasonic power of 131 W, microwave power of 105 W, ratio of water volume to raw material weight of 62 mL/g and extraction time of 120 s. Under these conditions, the yield of polysaccharides could be up to 9.15 +/- 0.13%, which was increased by 405.52%, 128.18% and 76.64% compared to hot water extraction (HWE), ultrasonic-assisted extraction (UAE) and microwave-assisted extraction (MAE), respectively. Furthermore, according to the size-exclusion chromatography connected with multi-angle laser light-scattering and refractive index (SEC-MALLS-RI) system, the molecular weight of FMPS was distributed mainly in the range 1.828 x 10(5)-9.563 x 10(5) g/mol and it accounted for 62.60% of total polysaccharides. The molecular weight and radius of FMPS did not display positive correlation. FMPS were composed of four polysaccharide fractions with different molecular weight. The polysaccharide fractions could be separated according to their molecular structural characteristics. (c) 2015 Elsevier B.V. All rights reserved.

Lotus seed resistant starch (LRS) is commonly known as resistant starch type 3 (LRS3). The objective of this study was to investigate the effect of different preparation methods on the structural characteristics and physicochemical properties of LRS3. The molar mass of LRS3 prepared by autoclaving method (GP-LRS3) and ultrasonic-autoclaving method (UP-LRS3) was mainly distributed in the range 1.0 × 104–2 × 104 g/mol while a decrease of LRS3 prepared by microwave-moisture method (MP-LRS3) was observed. The particle of MP-LRS3 was smaller and relatively smoother while UP-LRS3 was bigger and rougher compared to GP-LRS3. Among these samples, GP-LRS3 exhibited the highest degree of ordered structure and crystallinity, the amorphous region of MP-LRS3 was the biggest and UP-LRS3 displayed the highest degree of double helical structure. Additionally, MP-LRS3 displayed the strongest solubility and swelling power while UP-LRS3 exhibited the strongest iodine absorption ability and thermostability, which were affected by their structural characteristics.

In order to understand the multiple relationships between the structural characteristics and hypolipidemic effect of polysaccharides from Fortunella margarita (Lour.) Swingle (FMPS), four polysaccharide fractions, FMPS1, FMPS2, FMPS3 and FMPS4, were isolated from FMPS by the column chromatography using DEAE Sepharose CL-6B and Sephadex G-100. The results showed that FMPS1 and FMPS3 were mainly pectic polysaccharides while FMPS2 and FMPS4 were mainly composed of neutral polysaccharides. FMPS1, FMPS2 and FMPS3 linked by α- and β-glycosidic linkages while FMPS4 only linked by β-glycosidic linkages. According to the size-exclusion chromatography coupled with multi-angle laser light-scattering and refractive index (SEC-MALLS-RI) system, the molecular weight of FMPS1 and FMPS2 was greater compared to FMPS3 and FMPS4. The chain conformation analysis indicated FMPS3 and FMPS4 were highly branched polymers whereas FMPS1 and FMPS2 existed as globular shape and random coil conformation in aqueous, respectively. In addition, among the four polysaccharide fractions, FMPS1 and FMPS3 displayed the stronger inhibitory effect on the pancreatic lipase, FMPS1 and FMPS2 displayed the stronger ability to bind bile acids, and FMPS3 and FMPS4 displayed the greater antioxidant activity. The hypolipidemic activity of polysaccharide fractions was affected by the monosaccharide composition, glycosidic linkage, molecular weight and chain conformation in aqueous. This functional property was a result of a combination of multiple structural factors.

Lotus seed native starch was applied to prepare lotus seed retrograded starch and used as raw material by microwave method. The process parameters of lotus seed resistant starch were optimized by using single factor and orthogonal optimization analysis. The results indicated that starch concentration had the greatest impact on the yield of lotus seed resistant starch, microwave treatment time and microwave power was followed.The best conditions for microwave preparation were starch concentration 15%, microwave treatment time 120 s, microwave power 640 W, the yield of resistant starch was 39.56%under these conditions, less than autoclaving and ultrasonic-autoclaving process. However,with microwaving process, lotus seed resistant starch was easy to acquire and needed shortest time,it can be used wildly in industrial applications or large quantities of preparation in the laboratory.

In order to study the structure of lotus（Nelumbo nucifera Gaertn） seed oligosaccharides and their effect on the proliferation of Bifidobacterium adolescentis, we extracted the oligosaccharides from seeds collected from Jianning County, China. We preliminarily characterized the groups, molecular weights, molecular formulae, component monosaccharides and glycosidic bonds using mass spectrometry（MS） and nuclear magnetic resonance（NMR） after isolation and purification. The lotus seed oligosaccharides contained glycosidic bonds Manp-（1→）, Galp-（1→）, α（1→6）-Glup and α（1→6）-Manp; and mannose was the chief component monosaccharide. NMR analyses showed that α-glycosidic bonds and pyranoid rings were predominant in the oligosaccharides. The MS analyses showed that lotus seed oligosaccharides consisted of three oligosaccharides of different polymerization degree, with relative molecular weights of 342, 504 and 666 Da, and corresponding molecular formulae C12H22O11, C18H32O16 and C24H42O21. Research on the effect of lotus seed oligosaccharides on the proliferation of B. adolescentis showed that they effectively promoted the production of acetic, propionic and butyric acids by B. adolescentis through fermentation, and their effect was stronger than that of fructo-, xylo- and isomalto-oligosaccharides. Lotus seed oligosaccharides have potential as a new functional probiotic and lotus seeds should be further explored and utilized as a source of oligosaccharides.

主要探讨利用废旧工业用地构建城市公共绿地景观.从城市景观构成的角度入手,通过对城市中用于绿地改造的废旧工业用地的历史背景、原有地构性质的分析,并借鉴国内外经典案例,探讨废旧工业用地的现代绿地景观改造的原则、理论与方法.

In independent college,based on the students' poor cultural foundation and weak study consciousness,the College Chinese is not only charged with improving the students' skills of expression and writing,but also improveing the reality of teaching content,the interest and interaction of teaching means,thereby to improve the students' humanity quality.

李广是西汉时期著名的边将,唐代边塞诗中出现了大量与他有关的诗句。在这些诗中,"李广"或是英勇善战,抚爱士卒,让人赞赏;或是才高难封,命运不偶,让人感叹。诗人或借"李广"表达他们对边战立功的强烈渴望,或借"李广"抒发怀才不遇的愤慨。总体来说,唐代边塞诗中的"李广"是完美的。然而唐代不同时期的这些诗作反映的格调是不一的,唐代边塞诗中"李广"形象的变化也从一个侧面反映了唐王朝由盛而衰的历史。