芝麻叶中总黄酮的最佳提取工艺研究

该文测定了芝麻叶中总黄酮的含量，并对芝麻叶黄酮的提取工艺进行了研究。重点探讨了采用乙醇提取法和微波处理与乙醇提取相结合的方法提取芝麻叶黄酮类化合物的最佳工艺条件。试验结果表明：芝麻叶中总黄酮的含量为0.98%；乙醇提取法的最适工艺参数是浸提剂乙醇浓度为80%、浸提温度为80℃、料液比为1∶25、浸提时间为2.5 h，如此条件可使黄酮提取率达95.6%；微波处理与乙醇提取相结合的方法的最适工艺参数是微波功率200 W、微波处理时间70s，乙醇浓度为80%、浸提温度为80℃、料液比为1∶25、浸提时间为30 min，这种工艺可使黄酮提取率达95.8%。     

熏蒸浸提法测定碱性土微生物生物量碳初探

为探究熏蒸浸提法测定碱性土壤微生物生物量碳(microbial biomass carbon,MBC)的最优熏蒸时间和浸提液浓度,本研究采用9种熏蒸时间、2种K_2SO_4浸提液浓度对不同有机质含量的碱性土壤MBC进行了测定。结果表明:(1)对于碱性土壤,熏蒸时间的选择与土壤有机质含量有关,土壤有机质含量越高,MBC提取值达到稳定的熏蒸时间越长。建议测定高有机质土壤(≥60 g/kg)MBC时熏蒸时间不少于24 h;测定中、低有机质土壤(≤30g/kg)MBC时熏蒸时间不少于18 h。(2)土壤有机质含量影响K2SO4浸提液的提取效率,测定高、中有机质土壤MBC时需要0.5 mol/L K_2SO_4浸提液进行提取;在低有机质土壤MBC测定中,0.25 mol/L K_2SO_4浸提液即可。(3)对于未知有机质含量的碱性土壤建议氯仿熏蒸时间至少为24 h,K_2SO_4浸提液浓度为0.5 mol/L。     

二次正交旋转组合设计优化牛肝菌蛋白提取工艺

为明确牛肝菌蛋白提取条件,以牛肝菌子实体为材料,碱溶液为提取剂,在单因素试验基础上,采用四因素五水平的二次正交旋转组合试验设计,研究碱浓度、浸提温度、浸提时间和液固比对蛋白质提取得率的影响,经统计分析,建立数学回归模型。结果表明,所得回归方程达到极显著水平,无失拟因素存在;通过频率分析法得到的牛肝菌蛋白质的最佳提取工艺为:Na OH浓度0.11mol·L~(-1),液固比31∶1,浸提温度62℃,浸提时间1.70 h,此条件下蛋白质实际提取得率为19.85%。本试验优化牛肝菌蛋白的提取工艺参数准确可靠、稳定、可行,为牛肝菌蛋白功能的进一步研究和食用菌功能性食品开发提供了一定的技术依据。     

玉米酒精发酵前提取超氧化物歧化酶的研究

该文研究了在不影响玉米制取燃料酒精的情况下,先从玉米中提取超氧化物歧化酶(SOD)的工艺,从而提高了玉米综合利用的价值。试验表明：提取SOD时玉米浸泡的最佳条件为添加玉米质量2倍的0.05 mol/L磷酸盐缓冲液(pH 7.8),在40℃浸泡36 h。SOD提取浸提工艺采用0.05 mol/L磷酸盐缓冲液(pH 7.8),以液料比2∶1(v/m)加入,粉碎,浸提1 h。浸提液离心后添加硫酸铵至40%饱和浓度去除杂蛋白,再添加硫酸铵至90%饱和浓度盐析,得到SOD粗酶制剂,比活为168.3 U/mg。     

真姬菇子实体多糖的提取工艺优化

为优化真姬菇子实体多糖的提取工艺,以水为浸提液,通过单因素试验研究了浸提温度、浸提时间、液固比、乙醇用量和提取次数对真姬菇多糖得率的影响,并采用二次回归正交旋转组合设计试验对提取工艺进行优化.结果表明,多糖得率的主要影响因素及其顺序为浸提温度、浸提时间、液固比;在乙醇用量为2倍、提取次数为1次时,最佳提取工艺参数为浸提温度95℃、浸提时间2.84h、液固比11.6∶1,多糖得率为4.47%.     

红叶芥色素提取工艺及其性质的研究

本文以50%乙醇为溶剂,从浸提温度、浸提时间、浸提剂pH值及不同料液比几个方面对红叶芥色素提取方法及其稳定性进行研究。结果表明:红叶芥色素的最佳提取条件为pH值在3到4的范围内、提取温度60℃、时间0.5 h、料液比l∶30。     

枳实副产物中柠檬苦素最佳提取条件的研究

通过单因素试验和旋转正交试验对枳实副产物中柠檬苦素的提取工艺进行优化。结果表明：最佳提取工艺参数为提取剂乙醇浓度78％、pH值6.5、料液比1∶6(w/v)、浸提温度60℃、提取时间2 h，该条件下柠檬苦素的提取率为94.2％。     

不同浓度螯合剂和浸提时间对土壤磷素提取效果研究

为确定螯合剂活化土壤磷素的最佳浓度和最优浸提时间,参考水肥一体化技术,在室内浸提条件下,研究了不同浓度(0,0.05,0.1,0.25,0.5,1.0g/L)乙二胺四乙酸(EDTA)和柠檬酸螯合剂(pH=4)在不同浸提时间(1,12,24,48,72h)下对粮田、菜田土壤和有效磷被钝化后菜田土壤中磷素提取效果。结果表明:EDTA和柠檬酸在粮田土壤上对磷素提取中最佳条件为螯合剂浓度0.05g/L,浸提时间12h。EDTA和柠檬酸在菜田土壤、明矾钝化和混合钝化(明矾∶白云石为1∶1)菜田土壤上提取磷素的最佳条件为螯合剂浓度0.5g/L,浸提时间12h;而在白云石钝化土壤中则为螯合剂浓度0.5g/L,浸提时间1h。总体来看,柠檬酸的活化提取磷素效果优于EDTA,尤其是在采用明矾和白云石钝化的土壤上。     

酸性土壤有效汞提取方法研究

为了更好地评价酸性土壤中汞的生物有效性和生态风险,以酸性土壤为供试土壤,通过比较国内外几种常用的土壤有效汞的浸提剂的提取效果,筛选适合于酸性土壤的有效汞浸提剂并优化相应的提取条件,从而建立酸性土壤有效汞的提取方法。结果表明,在0.1 mol·L-1HCl、1 mol·L-1NH4OAc、0.005 mol·L-1DTPA、0.03%TGA-1/15 mol·L-1Na2HPO4这4种常用浸提剂中,0.03%TGA-1/15 mol·L-1Na2HPO4是最佳的浸提剂,因为它具有最高的提取率,且其所提取的有效汞与相应稻米中Hg含量的相关性最好。0.03%TGA-1/15 mol·L-1Na2HPO4的最佳浸提条件为土液比1∶10、振荡时间120 min、振荡速度250 r.min-1,浸提出的有效汞量与油菜的相关性达到极显著相关,能较好地指示田间条件下土壤汞对作物的可给性。     

土壤有效态重金属提取剂选择的研究

利用5种不同的土壤重金属浸提剂,研究了土壤有效态重金属含量与玉米重金属含量的关系,并提出了一种新的土壤有效态重金属的浸提剂。结果表明:0.1mol/L HCl,0.05mol/L EDTA-2Na,0.1mol/L CaCl2,0.1mol/L HAc-NaAc,0.05mol/L DTPA提取的化学有效态重金属与玉米根、茎、叶中重金属Cu、Zn、Cd、Pb大部分呈显著或极显著相关,但各化学提取剂提取的有效态Zn、Cu与玉米籽粒Zn、Cu的相关性较差。利用柠檬酸-酒石酸为提取剂提取的重金属含量与玉米籽粒中重金属的含量有着相对较好的相关性,是一种预估玉米籽粒中重金属含量的较好办法。     

不同浸提条件对包膜控/缓释肥水中溶出率的影响

以几种不同包膜材料控／缓释肥为供试肥料,研究不同肥(养分)水比、浸提方式(连续浸提和更换浸提液)、温度和pH条件对控／缓释肥水中溶出率的影响。结果表明,浸提液中肥料浓度是影响养分释放的重要因素,加大肥水比、更换浸提液可以显著减小这种影响。升高温度,有机和无机材料包膜控／缓释肥水中溶出率均显著加快。肥料类型、肥水比对浸提液的pH都有显著影响,但在连续浸提和更换浸提液方式下,7d内浸提液的pH有着不同的变化趋势。控／缓释肥在pH.5的磷酸盐缓冲液中的溶出率显著高于在pH.7的磷酸盐缓冲液中的溶出率。因此,对于不同包膜材料控／缓释肥以一定pH值的微酸性缓冲溶液作为浸提剂,定期更换浸提液或采用动态流法,相同的氮(或磷、钾)水比,30℃左右的浸提条件是较为合理的。     

Effects of Vermicompost Tea (Aqueous Extract) on Pak Choi Yield,Quality, and on Soil Biological Properties

This study investigated the effects of vermicompost tea (aqueous extract) on yield and chemical quality of pak choi (Brassica rapa cv Bonsai, Chinensis group) grown in three media (two soils and a peat-perlite medium) under two fertilizer regimes (compost and synthetic fertilizer). The impacts of tea application on the chemical and biological properties of the growth media were also investigated. Vermicompost teas were prepared using various extraction methods (non-aerated, aerated, aerated with additives) with 1:10 (v:v) chicken manure-based vermicompost to water dilution and applied weekly at the rate of 200 mL plant^?1 for 4 weeks. Application of vermicompost tea increased plant production, total carotenoids and total glucosinolates in plant tissue. This effect was most prominent under compost fertilization. Total phenolic was lower in vermicompost tea treated plants compared to those treated with only mineral nutrient solution and the water control. Vermicompost tea improved mineral nutrient status of plants and media, and enhanced the biological activity of the media. Variability in yield and chemical quality of plants across treatments was explained largely by variability in tissue N uptake and dry matter accumulation. Dehydrogenase activity and soil respiration of vermicompost tea-treated growth media were approximately 50% higher than untreated media. This study confirmed that vermicompost tea can positively influence plant yield and quality and increase soil biological activity in multiple soil types.     

滴施酸性有机肥浸提液对棉田土壤养分活化和利用效率的影响

【目的】 随着水肥一体化施肥方式的应用,新疆棉花生产化肥投入量大大增加,有机肥投入不断降低。本研究探索用磷酸和硝酸浸提有机肥养分,利用酸性有机肥浸提液替代部分化肥的效果,为增加有机肥施用提供途径。 【方法】 以腐熟鸡粪有机肥为原料,在塑料桶内,分别用pH为1的硝酸和磷酸,按照浸提剂与有机肥的质量比为5∶1进行浸提,恒温箱内保持25℃恒温,每8小时搅拌一次,浸提持续2天。浸提结束后用0.038 mm尼龙网过滤,滤液用于滴灌施肥。以不施肥、施用常规化肥和硝酸有机肥浸提液作对照 (代号依次为CK、CK1和NAE-CK);设置有机肥浸提液替代全量的磷肥、2/3磷肥和1/3磷肥三个替代量,施肥量分别为4950 L/hm2、3300 L/hm2、1650 L/hm2 (代号:PAE、2/3PAE、1/3PAE);再以pH为1的硝酸和磷酸为对照 (HN-CK、HP-CK),所有施肥处理以化肥补足至总养分量一致。分别在第五次施肥后5天 (花铃期),第八次施肥后10天 (吐絮期),在距滴灌带滴头处 (0 cm) 以及距离滴头15 cm和30 cm处,分别采集0—20 cm、20—40 cm和40—60 cm土壤,测定土壤有机质、氮、磷、钾等有效养分含量。棉花成熟后每小区取植株3株,测植株氮磷钾吸收量,以实收产量计产。 【结果】 1) 施用两种有机肥浸提液与施用硝酸和磷酸浸提剂相比,土壤有机质含量增加了1.4%～16.8%,而单施对应的酸性浸提剂却使土壤有机质含量较CK降低10.2%～25.5%。2) 酸性有机肥浸提液代替部分化肥较常规施肥均不同程度提高了土壤水平0—30 cm与垂直0—60 cm范围内氮、磷、钾有效养分的含量,尤其对0—20 cm土壤的磷有明显的活化作用,增加了作物对其吸收量。1/3磷肥替代量处理对土壤养分最高提升6.3%,但差异不显著;2/3磷肥替代量和替代全部磷肥处理对土壤养分别最高提升35.3%和58.1%,差异均达到显著水平。3) 磷酸有机肥浸提液和磷酸浸提剂处理对土壤磷和钾有明显的活化作用,磷酸有机肥浸提液效果优于硝酸有机肥浸提液;有机肥浸提液的pH与土壤速效磷呈负相关 (–0.491*),浸提液有机质含量与土壤速效钾有显著正相关 (0.497*)。4) 施用4950 L/hm2的硝酸有机肥浸提液对氮的利用效率最高 (53.1%),4950 L/hm2的磷酸浸提剂对磷和钾的利用效率最高 (28.9%和344.8%)。 【结论】 有机肥浸提液作为一种新型酸性有机肥料,不仅适合新疆的滴灌施肥,还可以增加土壤有机质含量,活化新疆石灰性土壤的养分,尤其对于0—20 cm土壤的磷钾肥的利用效率提高显著。等施肥量下,磷酸有机肥浸提液对土壤的磷,钾活化效率高于硝酸有机浸提液,磷酸有机肥浸提液施肥量为3300 L/hm2时棉花产量最高,养分农学利用效率最高。      

A method for extracting sulfate from sphagnum peat

Abstract

The efficacy of five solutions for extracting sulfate from a peat‐based medium was investigated. Extracting solutions used were 10 mM LiCl, 10 mM KC1, 100 mg/L P, 500 mg/L P, 0.15% CaCl₂, or distilled water. Equilibration time affected the amount of sulfate extracted with the use of 100 mg/L P or distilled water extractants. Differences in the amount of sulfate extracted were observed at 0.5‐, 4‐, and 12‐hour equilibration times. Extraction effectiveness increased with the increase of equilibration time, up to a maximum of 4 hours. The concentration of sulfate extracted with all extractants levelled off at the 2‐hour equilibration time. CaCl₂ was the most effective solution for the extraction of water‐soluble sulfate. Water‐soluble sulfate plus absorbed sulfate was most efficiently extracted with 500 mg/L P. No relationship was observed between measured sulfate and the pH levels of the extracted solutions.     

Estimation of potassium concentration in oil palm (Elaeis guineensis Jacq.) leaf tissue by simple and inexpensive water extraction method

Estimation of potassium (K) concentration in oil palm leaf tissue is routinely carried out in oil palm plantations to manage fertilizer application for getting higher fresh fruit bunch (FFB) production. Since K in plant tissue is not bound to organic complexes and it is extractable by water, this study was carried out to extract K from oil palm leaf tissue by water extraction method. The results were compared with other established methods like 1 normal (N) ammonium acetate (NH₄OAc) extraction, 0.5 N hydrochloric acid (HCl) extraction, and diacid digestion. The proposed water extraction method consists of shaking of 0.5 g finely ground oil palm leaf tissue with distilled water at 1:60 ratio [sample-to-water weight (w)/volume (v)] for a period of 20 min in a reciprocating shaker, filtration of the content, and measurement of K concentration in filtrate by flame photometer. The results of analysis of 30 oil palm leaf samples collected from various production systems under different soil types and management practices for K concentration revealed the close agreement of water extraction method with other established methods. The mean value of K extracted by water extraction method was within 1–10% of the K extracted by other established methods. Water-extractable K was significantly correlated with K extracted by other methods and it could be predicted by other methods. The values of standard error and coefficient of variation for K extracted by different methods were very low, which indicated that the water extraction method was comparable with other established methods.     

牛骨蛋白与多糖的逐级提取及分离方法研究

为确定牛骨中蛋白质和多糖的提取及分离方法，该文在分析骨胶原蛋白和多糖存在状态的基础上，分别利用不同溶剂探讨了牛骨中蛋白质与多糖的逐级提取方法。首先碱性蛋白、酸性蛋白分别被0.6 mol/L KCl和0.5 mol/L K-P(K₂HPO₄/KH₂PO₄)溶液提取出来；0.1 mol/L HCl脱钙时溶解出酸性、中性及碱性蛋白，再经过NaOH中和后，酸性蛋白随羟基磷灰石沉淀、中性及碱性蛋白存留在上清液中；其他在胶原纤维上的有机物被0.5 mol/L NaCl和1% Na₂CO₃分别提取出来。各级提取有机物用SDS-PAGE电泳以及Stains All染色法、阿里新兰染色和CBB染色进行检测。利用DEAE-葡聚糖凝胶离子交换树脂有效地将碱性蛋白、酸性蛋白和多糖分离精制。     

Effects of solvent and temperature on pressurized liquid extraction of anthocyanins and total phenolics from dried red grape skin

Pressurized liquid extraction (PLE) was used to extract anthocyanins from the freeze-dried skin of a highly pigmented red wine grape with six solvents at 50 degrees C, 10.1 MPa, and 3 x 5 min extraction cycles. Temperature (from 20 to 140 degrees C in 20 degrees C increments) effects on anthocyanin recovery by acidified water and acidified 60% methanol were also studied. Acidified methanol extracted the highest levels of total monoglucosides and total anthocyanins, whereas the solvent mixture (40:40:20:0.1 methanol/acetone/water HCl) extracted the highest levels of total phenolics and total acylated anthocyanins. Acidified water extracts obtained by PLE at 80-100 degrees C had the highest levels of total monoglucosides, total acylated anthocyanins, total anthocyanins, total phenolics, and ORAC values. Acidified methanol extracts obtained by PLE at 60 degrees C had the highest levels of total monoglucosides and total anthocyanins, whereas extracts obtained at 120 degrees C had the highest levels of total phenolics. High-temperature PLE (80-100 degrees C) using acidified water, an environmentally friendly solvent, was as effective as acidified 60% methanol in extracting anthocyanins from grape skins.     

低分子量有机酸对紫色母岩中钾释放的影响

采用4种浓度为0.05mol/L的低分子量有机酸溶液分别浸提4种紫色母岩风化碎屑和2种紫色土3000h研究其钾的释放规律。结果表明,与纯水浸提相比,0.05mol/L的草酸、酒石酸、柠檬酸以及苹果酸4种低分子量有机酸溶液都能明显促进6种供试样中钾的释放,释放量提高0.3～15.2倍。4种有机酸活化6种供试样中钾的能力以草酸柠檬酸酒石酸苹果酸。侏罗纪沙溪庙组紫色泥岩、沙岩和侏罗纪遂宁组紫色泥岩以及灰棕紫泥4种土壤(或岩样)中钾的释放过程在3000h内用Elovich、双常数、抛物线、一级扩散和双曲线方程等5种动力学方程拟合,结果除一级扩散方程较差外,其它4种方程拟合的相关系数r=0.5988～0.9966(r0.01=0.6055),以双常数方程拟合效果最佳。拟合方程中常数b值可表征钾的释放速度。     

Effect of solvent, temperature, and solvent-to-solid ratio on the total phenolic content and antiradical activity of extracts from different components of grape pomace

Grape byproducts were subjected to an extraction process under various different experimental conditions (namely, solvent type, temperature, solvent-to-solid ratio, time contact, and raw material) in order to study the effect of these conditions on the yield of phenolic compounds and the corresponding antiradical activity of extracts. Although the order of decreasing capacity to extract soluble materials was ethanol > methanol > water, methanol was the most selective for extracting phenolic compounds. Temperature and solvent-to-solid ratio were found to have a critical role in extraction efficiency; values of 50 degrees C (between 25 and 50 degrees C) and 1:1 (between 1:1 and 5:1) maximized the antiradical activity of phenolic extracts. In addition, extracts from grape samples previously subjected to distillation reached higher antiradical values in comparison to those coming directly from pressing; in both cases, seed extracts showed better results than those of stem when ethanol or water was employed, whereas the opposite occurred in the case of methanol. These differences were attributed to the different phenolic compositions of the considered fractions.     

用于表征三七种植区土壤中可利用态砷的化学提取剂的筛选

为正确表征云南文山三七种植区土壤中植物可利用态砷,选取NaH2PO4（0.5mol·L-1）、H2O、H3PO4（0.2mol·L-1）、EDTA（0.0625mol·L-1,pH=7）、NH4C（l1.0mol·L-1）和（NH4）2SO（40.05mol·L-1）6种提取剂,比较了它们对土壤中砷的提取效果,及其所提取的砷与三七植株各部位砷含量之间的相关关系。结果表明,NaH2PO4、H3PO4和（NH4）2SO4这3种提取态砷与土壤总砷呈极显著正相关,相关系数分别为0.8359、0.8177和0.8810。NaH2PO4和H3PO4的提取效率较高,平均提取效率分别为6%和11%;而（NH4）2SO4提取效率较低,平均仅为0.084%。NaH2PO4和（NH4）2SO4提取态砷与三七主根、须根和茎部砷含量呈显著正相关,H3PO4提取态砷与三七主根和须根砷含量呈显著正相关。综合考虑认为NaH2PO（40.5mol·L-1）是最佳提取剂,H3PO（40.2mol·L-1）提取剂次之,这两种提取剂均可较好地表征土壤中砷的三七可利用性。