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61.
长三角地区农作物秸秆资源量的时空分布特点   总被引:1,自引:0,他引:1  
为提高长三角地区秸秆资源的综合利用率,采用草谷比法,评估长三角地区秸秆的资源量和秸秆资源的分布特点。结果表明:2000-2014年长三角地区农作物秸秆资源总量呈稳中上升趋势;秸秆分布地区格局差异显著;作物秸秆产量主要分布在粮食主产区的江苏省和安徽省,浙江省和上海市则比较低,2000-2014年作物秸秆资源量为江苏安徽浙江上海;农作物秸秆主要类型为稻谷、小麦和油菜籽,以稻谷为长三角地区最主要的粮食作物秸秆。  相似文献   
62.
This study illustrates the optimisation of the experimental conditions of three sequential steps for chondroitin sulphate (CS) recovery from three cartilaginous materials of Scyliorhinus canicula by-products. Optimum conditions of temperature and pH were first obtained for alcalase proteolysis of head cartilage (58 °C/pH 8.5/0.1% (v/w)/10 h of hydrolysis). Then, similar optimal conditions were observed for skeletons and fin materials. Enzymatic hydrolysates were subsequently treated with a combination of alkaline hydroalcoholic saline solutions in order to improve the protein hydrolysis and the selective precipitation of CS. Ranges of 0.53–0.64 M (NaOH) and 1.14–1.20 volumes (EtOH) were the levels for optimal chemical treatment depending on the cartilage origin. Finally, selective purification and concentration of CS and protein elimination of samples obtained from chemical treatment, was assessed by a combination of ultrafiltration and diafiltration (UF-DF) techniques at 30 kDa.  相似文献   
63.
The effect of organic amendments on the interactions between Striga hermonthica and a sorghum host was studied in a field experiment during three cropping seasons, following a three-factorial design with (i) bare fallow versus continuous cropping, (ii) two Strigahermonthica infection levels and (iii) five organic matter levels, a single inorganic fertiliser treatment of 120 kg N ha−1 and a control. The effects of two different cotton by-products and their mixtures on sorghum yield were well described by their N-mineralisation pattern. The impact of organic amendments in the sorghum production system was directly related to N-mineralisation in the three cropping seasons. There was an increasing negative effect of organic matter on S. hermonthica as the quality of the applied material increased. The emerged numbers of S. hermonthica were well described by N-release after one month, while S. hermonthica biomass and sorghum biomass were well described by N-release after three months. As a stand-alone measure, addition of low-quality organic matter is disadvantageous in cropping systems with high S. hermonthica seed densities, as it does not improve sorghum performance compared to no addition of organic matter, while S. hermonthica numbers increase. Implications for integrated soil fertility and S. hermonthica management under different infection levels of S. hermonthica are discussed.  相似文献   
64.
酶解日本对虾副产物主要成分及其可溶性肽组成分析   总被引:1,自引:0,他引:1  
为确定酶解日本对虾(Penaeus japonicus)加工副产物的主要成分及其可溶性肽相对分子质量组成,采用多酶分步水解技术制备日本对虾加工副产物的酶解产物(EHP)。用高效液相色谱法、紫外可见分光光度法、索氏法、化学分析法等方法,分析EHP主要营养组成及其肽的相对分子质量。结果表明,EHP含蛋白质67%、粗脂肪1.0%、类胡萝卜素0.12%、钙6.7%、磷0.4%。EHP中的最长肽链相对分子质量为13 800,仅占0.32%;相对分子质量在5 400~1 550的肽占35.72%、相对分子质量小于1 000的小肽占52%。每100 g EHP干基中的总氨基酸含量50.185 g、人体必需氨基酸17 g,鱼虾10种必需氨基酸22 g,鲜味氨基酸24.7 g。  相似文献   
65.
The hydrolysis process for Silver carp by-products was studied. Protein hydrolysate was prepared with proteolytic enzyme, Alcalase. Hydrolysis conditions were optimized by the regression model of three factors five levels quadratic rotation perpendicular regressive design. The optimum hydrolysis conditions of hydrolyzing the protein of Silver carp by-products were determined to be concentration of enzyme (E/S) 3.33%, pH 8.54, hydrolyzing temperature 58℃, reaction time 90 min, concentration of substrate 8%. Nitrogen recovery was more than 75%.  相似文献   
66.
After a brief overview of the general production, market value, and uses of citrus by-products, this literature review will focus on the most highly refined “pharmaceutical grade” citrus oils and antioxidants that have been derived from peels or other fruit parts. Citrus oils have been used as a part of the perfume industry and in the practice of alternative medicine for a long time, but now there is a great deal of mainstream food processing and drug industry interest in them owing to the rediscovery or confirmation of some of their beneficial properties, as well their development for entirely new applications. Their roles as antimicrobial, immunomodulatory, and cancer chemopreventive or chemotherapeutic agents appear promising.  相似文献   
67.
The digestible energy (DE) content and the apparent digestibility coefficients (ADCs) of nutrients in common feed ingredients available in Atlantic Canada for haddock, Melanogrammus aeglefinus, feed formulations were determined. Juvenile haddock (mean weight, 93.9±2.1 g) were held in tanks equipped with fecal collection columns and fed practical fish meal‐based diets for 5 weeks. The experimental diets consisted of a reference diet and six test diets, each containing 30% test ingredient, with all diets being supplemented with chromic oxide (Cr2O3, 5 g kg?1) as the inert digestion indicator. Three marine fish by‐products, herring meal (HM), shrimp meal (SM) and crab meal (CRM) and three plant protein supplements, dehulled soybean meal (SBM), canola meal (CAM) and corn gluten meal (CGM) were the test ingredients. The DE content of HM, SBM, CGM, CRM, CAM and SM were 18.3, 18.0, 17.8, 12.4, 10.9 and 8.8 MJ kg?1 respectively. Protein ADCs were 95.9%, 92.2%, 92.3%, 82.0%, 83.0% and 73.5% respectively. Organic matter ADCs were 95.9%, 89.0%, 72.6%, 68.9%, 58.9% and 54.9% respectively. Lipid ADCs were 97.9%, 83.0%, 57.4%, 62.0%, 87.2% and 55.8% respectively. Based upon its high crude protein content and nutrient ADC and DE content, properly processed dehulled SBM was found to be a good plant protein supplement to partially replace HM in haddock feeds.  相似文献   
68.
Three trials, with classical experimental designs for in vivo digestibility studies, were conducted to determine the apparent digestibility coefficient (ADC) of protein (ADCp), lipid (ADCl), energy (ADCe) and amino acids (AA) in selected animal by-products fed to European sea bass, Dicentrarchus labrax (Trial 1), gilthead sea bream, Sparus aurata (Trial 2), and turbot, Psetta maxima (Trial 3). In each trial, five experimental diets [including a reference diet (RD)] where fish meal (FM) was used as the sole protein source were fed ad libitum to the fish for a period of 4 weeks. Test diets were based on the FM RD and obtained by replacing 30% of the RD with a category III designated European animal by-products (fit for human consumption), namely: steam hydrolysed feather meal (HFM), enzyme-treated feather meal (EFM), poultry meat meal (PMM) and spray-dried haemoglobin meal (SDHM). Faecal material was collected using the 'Guelph system', and nutrient and energy digestibility coefficients were related to the measurement of chromic oxide (Cr2O3) incorporated into the diet at a rate of 0.5%. Without any exception, FM diets yielded the best digestibility values for all macro-nutrients and by all fish. Among the test ingredients, ADCp was consistently higher for PMM and SDHM in the three species (85.5%, 91.1% in sea bass; 79.2%, 82.8% in sea bream; and 78.4%, 74.8% in turbot). Conversely, ADCp of HFM and EFM were less efficiently digested (67.2%, 68.2% in sea bass; 21.5%, 21.7% in sea bream; and 46.6%, 36.0% in turbot). However, the novel processing method applied to feather meal did not considerably influence the digestibility of most of the nutrients in this feedstuff. The current investigation yielded valuable numerical ADC for EAA considered to be of prime importance in generating balanced diet formulations.  相似文献   
69.
鱼类加工副产物中胶原提取技术与性质分析   总被引:1,自引:0,他引:1  
鱼类加工产业发展的同时,不可避免地产生大量鱼皮、鱼鳞、鱼骨、鱼鳍、鱼鳔等不同鱼类加工副产物,如何对这些副产物进行高值加工利用引起广泛关注。目前,鱼类加工副产物的利用途径主要包括制作休闲食品、饲料鱼粉、胶原等。其中,因胶原产品的附加值空间大,以鱼类加工副产物为原料提取胶原成为当前研究的热点之一。在介绍不同鱼类加工副产物组成特点的基础上,阐述了近年来国内外以不同鱼类加工副产物为原料提取胶原的研究现状,总结分析了从不同鱼类加工副产物中提取胶原的提取率、产物纯度及性质,展望了以鱼类加工副产物为原料提取胶原的发展前景和方向,分析认为酸-酶结合法更适用于鱼胶原的提取,并具有广阔前景。  相似文献   
70.
本试验旨在研究家禽副产物酶解肽部分替代鱼粉对大菱鲆生长性能、消化指标和特异性免疫指标的影响。选取初始体重(10.32±0.26) g、大小均匀、体质健壮的大菱鲆450尾,随机分为5组,每组3个重复,每个重复30尾。首先配制含50%鱼粉的基础饲料,然后用家禽副产物酶解肽分别替代基础饲料中0(对照)、8%、16%、24%和32%的鱼粉,配制5种等氮等能的试验饲料,分别记为D0、D8、D16、D24、D32组。试验期为56 d。结果显示:家禽副产物酶解肽替代8%和16%的鱼粉对大菱鲆的增重率、存活率、特定生长率、饲料系数、肝体比、肥满度、脏体比等生长性能指标均无显著影响(P>0.05)。家禽副产物酶解肽替代鱼粉比例超过8%时,全鱼粗脂肪含量显著低于对照组(P<0.05)。D0、D8、D16组干物质表观消化率、粗蛋白质表观消化率和粗脂肪表观消化率显著高于D24、D32组(P<0.05)。D0、D8组肝脏中胃蛋白酶、胰蛋白酶活性显著高于D16、D24、D32组(P<0.05)。D0、D8组的血浆和肝脏中谷丙转氨酶、谷草转氨酶活性显著低于D24、D32组(P<0.05)。D8组血浆中补体3、补体4含量显著高于D24、D32组(P<0.05)。D0、D8组血浆中尿素氮、丙二醛含量显著低于D24、D32组(P<0.05)。D0、D8组的血浆中总抗氧化能力、超氧化物歧化酶活性以及总蛋白、甘油三酯、总胆固醇、葡萄糖含量显著高于D32组(P<0.05)。由此可见,在本试验条件下,以生长性能为基础,综合考虑消化、代谢、特异性免疫等指标,家禽副产物酶解肽替代大菱鲆饲料中鱼粉的适宜比例为8%。  相似文献   
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