稻子、小麦麸皮中可溶性非淀粉多糖的气相色谱法测定

讨论稻子、小麦麸皮中可溶性非淀粉多糖的气相色谱法测定。将稻子、小麦麸皮磨细后,用８０％乙醇萃取游离糖,剩余物在醋酸缓冲液（ｐＨ５．０）条件下分别用α－淀粉酶和α－葡萄糖苷酶酶解,除掉淀粉。非淀粉多糖用酸水解为各单糖,采用糖醇衍生化成乙酸酯的制备方法,用ＯＶ－１７０１石英毛细管色谱柱,可分离得到非淀粉多糖（ＮＳＰ）各组成单糖的色谱峰。并以自然界中不存在的阿洛糖作内标物,提高了定性定量分析的准确性,计算出了稻子、小麦麸皮中可溶性非淀粉多糖的含量。     

Production of ethanol from starch by co-immobilizedZymomonas mobilis-glucoamylase in a fluidized-bed reactor

The production of ethanol from starch was studied in a fluidized-bed reactor (FBR) using co-immobilizedZymomonas mobilis and glucoamylase. The FBR was a glass column of 2.54 cm in diameter and 120 cm in length. TheZ. mobilis and glucoamylase were co-immobilized within small uniform beads (1.2-2.5 mm diameter) of κ-carrageenan. The substrate for ethanol production was a soluble starch. Light steep water was used as the complex nutrient source. The experiments were performed at 35κC and pH range of 4.0-5.5. The substrate concentrations ranged from 40 to 185 g/L, and the feed rates from 10 to 37 mL/min. Under relaxed sterility conditions, the FBR was successfully operated for a period of 22 d, during which no contamination or structural failure of the biocatalyst beads was observed. Volumetric productivity as high as 38 g ethanol/(Lh), which was 74% of the maximum expected value, was obtained. Typical ethanol volumetric productivity was in the range of 15-20 g/(Lh). The average yield was 0.49 g ethanol/g substrate consumed, which was 90% of the theoretical yield. Very low levels of glucose were observed in the reactor, indicating that starch hydrolysis was the rate-limiting step.     

淀粉／聚乙烯共混物的降解

淀粉和聚乙烯二者极性差别很大，如何提高淀粉／聚乙烯共混物降解塑料中两相的相容性是此项研究的技术关键．采用添加增容剂［１］，或进行淀粉疏水改性［２］，或对聚乙烯进行亲水改性［３］的办法均取得了一定的进展．本文在提高相容性研究的基础上，又添加油酸和有机铁...     

Starch derivatives of high degree of functionalization 9: carboxymethyl starches

This paper describes the synthesis of carboxymethyl starch (CMS) ID various alcohols (methanol, ethanol, isopropyl alcohol) as slurry media and with different starch types. The products were investigated regarding their degree of substitution (DS), their reaction efficiency (RE), and their pattern of functionalization. The highest DS obtained ID a one-step procedure was 1.40 with a RE of 82%, applying isopropyl alcohol as slurry medium. Moreover, by using the synthesis concept via a reactive microstructure, CMS samples with high DS values can be achieved ID a one-step synthesis as well. A multi-step carboxymethylation ID methanol, on the other hand, leads to maximal DS values of 2.3 after 10 conversions, dependent on the amylose content of the starch. ¹H NMR spectroscopic investigations show a reactivity ID the order O-2 > O-6 O-3 for the samples prepared ID alcoholic slurry media. ID contrast, the CMS synthesized via reactive microstructure reveals a preferred substitution ID position 6 and a non-statistic distribution of the carboxymethyl groups along the chain. A significant amount of 2,3,4,6-tetra--functionalization, caused by the branched structure of starch, was found.     

Heterogeneity of starch granules and the effect of granule channelization on starch modification*

This paper reviews the discovery of channels ID starch granules and progress of research on their effects on granule modification and digestibility, their nature, hypotheses on how they are formed and why they are present, and genetic control of their occurrence. Emphasized ID the relationship of channels to starch derivatization. Channelization ID presented as additional evidence of the heterogenous nature of starch granules from source to source and within a single source. A new method of determining the location of anionic entities within starch granules that utilizes reflectance confocal laser scanning microscopy ID described.     

三甲基硅基淀粉醚的合成

本文以淀粉和三甲基氯硅烷(TMS-Cl)为原料,在吡啶中合成了三甲基硅基淀粉醚(TMSS).详细研究了反应温度、时间、吡啶以及三甲基氯硅烷(TMS-Cl)用量等对TMSS产率的影响.红外及核磁图谱表明,三甲基硅基被成功地引入淀粉的分子骨架.     

淀粉作用下沸石晶体的链状组装

采用淀粉辅助水热合成方法,得到了特殊的一维链状纯硅沸石分子筛。结果表明在淀粉作用下,多个分子筛晶粒在晶轴b方向的表面之间存在强的相互作用使得分子筛晶粒沿此方向自组织成一维链状结构,所得材料非常均匀,乙醇的加入会使得这些一维聚集体的侧向团聚增加。     

高填充可降解淀粉基聚烯烃材料的制备及其堆肥降解

制备了高填充的聚乙烯（PE）-淀粉-碳酸钙（CaCO3）三元复合材料,根据ASTM D6400标准对该材料进行了堆肥降解。采用熔体流动速率（MFI）、差示扫描量热分析（DSC）、扫描电镜分析（SEM）等方法研究了该复合材料的堆肥降解行为。结果表明：堆肥降解过程中,熔体流动速率（MFI）在堆肥1个月左右出现极小值;降解过...     

Synergistic effect of graphene oxide nanoplatelets and cellulose nanofibers on mechanical,thermal, and barrier properties of thermoplastic starch

In recent years, because of the limited availability of oil resources and the increasing concerns regarding environment protection, much attention has been drawn to produce packaging films based on degradable biopolymers instead of synthetic polymers. On the other hand, because of the high costs of oil extraction, raw materials and film production, and disposing of the waste products of synthetic films, the need to replace these films with less pollutant and more cost‐effective films is growing globally. In this study, to answer the need for replacing synthetic polymer films, nanocomposite films based on thermoplastic starch reinforced with cellulose nanofibers and graphene oxide nanoplatelets were produced and characterized. The results implied that the synergistic effect of cellulose nanofibers and graphene oxide nanoplatelets has played an important role in improving the mechanical properties of the films. The results showed that with the addition of cellulose nanofibers and graphene oxide nanoplatelets, the tensile strength and elastic modulus of starch film were increased from 3 and 32 MPa to 13 and 436 MPa, which corresponds to 438% and 1435% improvement, respectively. In addition, the oxygen permeability resistance and the water vapor transmission for samples containing 3 wt% of graphene oxide nanoplatelets was decreased by 78% and 30% compared with the thermoplastic starch film, respectively. The permeability coefficient of the samples containing 3 wt% graphene oxide nanoplatelets for oxygen, nitrogen, and carbon dioxide have proved to be 0.051, 0.054, and 0.047 barrer, which shows that these films can perform well as packaging films.