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1.
以可可果皮为原料,采用酸水解法提取水溶性膳食纤维和水不溶性膳食纤维。结果表明,可可水溶性膳食纤维的最佳提取工艺为:料液比为1∶30,水浴温度90℃,pH 2.0,提取时间30 min,得率为25.19%。可可膳食纤维总得率达57.99%,不溶性膳食纤维的持水力为5.23 g/g,溶胀性为11.42 mL/g。  相似文献   

2.
以提取卡拉胶后的麒麟藻废渣为原料,利用木瓜蛋白酶和α-淀粉酶对粗纤维进行酶解,制备膳食纤维。正交试验优化提取工艺,得出最佳工艺条件为:料液比为1∶30,时间1.5 h,温度为65℃,蛋白酶用量为0.35%、α-淀粉酶用量为1.5%,膳食纤维得率为35.58%。按照最佳工艺条件提取的麒麟藻渣膳食纤维,膨胀力10.93 mL/g,持水力721.72%。  相似文献   

3.
以菠萝皮渣为原料制备膳食纤维,考察超微粉碎、蒸汽爆破和挤压膨化3种物理改性方式对菠萝皮渣膳食纤维的基本成分、理化性质、形貌结构及生物活性物质溶出量的影响。结果表明:3种物理改性方式均能提高样品阳离子交换能力,增加多酚、黄酮物质的溶出量。其中蒸汽爆破处理能显著提高可溶性膳食纤维含量,在持水持油性方面表现良好。形貌结构分析结果显示,改性后的膳食纤维结构均发生不同程度的变化,但其主要成分及化学结构未受影响。综上所述,蒸汽爆破处理有助于改善菠萝皮渣膳食纤维的品质。  相似文献   

4.
本研究以大豆饼粕为原料,通过L(934)正交实验设计方法,就影响制备膳食纤维含量的碱浓度、温度、时间和酶用量4项因素进行了实验,确立了制备大豆膳食纤维的最佳工艺条件。利用本工艺,湿豆粕经浸泡、碱处理、酶解、干燥和超微粉碎等程序,即可得到大豆膳食纤维,工艺产率为85%,产品纤维素含量为80%,还以豆粕膳食纤维为原料研制出大豆纤维系列食品。产品的各项理化指标均达到了国家食品添加剂的有关标准。  相似文献   

5.
以夏枯草残渣为原料,研究碱液浸提法制备不溶性膳食纤维和可溶性膳食纤维的工艺流程,并对膳食纤维的性能进行测定。考察料液比、碱液质量浓度、提取温度及时间对提取率的影响。正交试验优化出的最优工艺条件为:料液比1∶20、碱液质量浓度15 mg/mL、水解时间2.5 h、提取温度40℃。在此条件下,不溶性膳食纤维的提取率为60%,可溶性膳食纤维的提取率为13.55%。性能测定结果显示:不溶性膳食纤维的持水力为7.27 g/g,膨胀力为17.33 mL/g;在胃环境(pH 2)和肠道环境(pH 7)中,可溶性膳食纤维  相似文献   

6.
为了研究超微粉碎对毛竹笋微观结构及营养成分的影响,利用激光粒度仪和扫描电镜对超微粉碎不同时间的毛竹笋微观结构进行表征,并用国标检测等方法对膳食纤维、蛋白质、脂肪、糖类及金属元素等营养成分含量变化进行分析。结果表明:随着超微粉碎时间的延长,粉体粒径显著变小,颗粒表面纤维结构被明显破坏;可溶性膳食纤维(SDF)含量增多,不可溶性膳食纤维(IDF)含量减少;糖类含量上升,蛋白质、脂肪和金属元素含量变化不显著;根据红外光谱图可知,超微粉碎后其中的氢键作用和糖类吸收峰均有所增强。  相似文献   

7.
研究旨在应用酶法提取咖啡果皮中膳食纤维,为高品质膳食纤维提取及产业化开发应用提供参考。单因素及响应面优化纤维素酶法提取咖啡果皮中可溶性膳食纤维的工艺条件,并对其功能特性进行分析。结果表明:纤维素酶法提取的最优提取工艺为:超纯水(V)∶咖啡果皮粉(m)=100 mL∶6 g,纤维素酶活添加量为22 FPU/mL,酶解温度40℃,酶解时间2 h,在此工艺条件制备可溶性膳食纤维得率为9.72%;其持水力为(35.72±0.33)g/g,溶胀力为(94.85±0.23)mL/g,结合水力为(26.97±0.54)  相似文献   

8.
为高效提取豆渣中的膳食纤维并加工豆基高纤饼干,本研究采用碱浸提法,通过单因素和正交试验探讨碱浓度、碱浸温度、碱浸时间和胰蛋白酶活力对豆渣中膳食纤维提取率的影响。进一步在鸡蛋、黄油、膳食纤维添加量单因素试验基础上进行酥脆值和感官评价响应面分析,优化豆基高纤饼干配方。结果表明:制备膳食纤维的最佳工艺条件为,碱浸温度90℃、碱浓度1%、碱浸时间35 min、添加0.25%的500 UI胰蛋白酶,提取率达到83.14%。豆基高纤饼干的最佳配方为:膳食纤维添加量4%、黄油添加量40.30%、鸡蛋添加量25.50%。品评试验证明,该工艺和配方可制得色泽金黄、口感酥松、具有特异豆香的高膳食纤维酥性饼干。最佳配比方案制作出的豆基高纤饼干各指标均满足国家标准,总体符合大众口感,市场潜力较好。豆基高纤饼干水分含量1.85±0.02 g·(100 g)-1,灰分含量1.49±0.03 g·(100 g)-1,粗蛋白含量5.83±0.42 g·(100 g)-1,可溶性膳食纤维含量0.13±0.03 g·(100 g)-1...  相似文献   

9.
通过单因素及正交试验优化纤维素酶法提取菠萝渣中可溶性膳食纤维的工艺条件,并对产品的功能特性进行分析。结果表明:纤维素酶法提取的较佳提取工艺为:蒸馏水(V)∶菠萝渣粉(m)=20(mL)∶1(g),纤维素酶添加量为30 U/g,pH4.8,温度40℃酶解2.0 h,在此工艺条件制备可溶性膳食纤维得率为(7.12±0.02)%,其持水力与溶胀力分别为(35.81±0.04)g/g和(73.50±0.12)mL/g。  相似文献   

10.
以豆渣为原料,并在碱液处理后直接挤压膨化制备豆渣水溶性膳食纤维.以水溶性膳食纤维得率为指标,对物料水分、挤压温度、螺杆转速及氢氧化钠浓度进行了单因素试验.采用响应面分析方法,对挤压膨化提高碱处理豆渣水溶性膳食纤维的工艺条件进行了优化,并建立了物料水分、挤压温度、螺杆转速三因素的回归模型.确定了挤压膨化碱处理豆渣制备水溶...  相似文献   

11.
12.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

13.
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.  相似文献   

14.
15.
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.  相似文献   

16.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

17.
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact).  相似文献   

18.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

19.
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.  相似文献   

20.
Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).  相似文献   

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