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1.
絮凝法预处理大豆蛋白活性肽发酵液的研究   总被引:3,自引:1,他引:2  
本文对絮凝法预处理大豆蛋白活性肽发酵液进行了研究,选用了7种絮凝剂,以FR值、滤速及肽的相对变化率为指标,考察了各种絮凝剂的絮凝效果。并从中选择了一种安全性高的絮凝剂——壳聚糖。并且对用壳聚糖絮凝处理大豆蛋白活性肽发酵液的方法进行了研究,讨论了pH、絮凝剂的浓度、温度和搅拌时间对絮凝效果的影响,得出了最佳的絮凝条件为:壳聚糖浓度为150mg/L;pH4.0;35℃;搅拌时间15min.  相似文献   

2.
壳聚糖在糖蜜酒精废液处理中的应用   总被引:3,自引:0,他引:3  
以壳聚糖作絮凝剂处理高浓度糖蜜酒精废液,考察了pH值、温度、搅拌时间、壳聚糖用量及助凝剂用量等对废液CODcr去除率的影响,结果表明,当pH为7.0、温度为25℃,搅拌时间为30min,静置时间2h,配合助凝剂P30的有效作用,能使糖蜜酒精废液的CODcr去除率达到96.2%。  相似文献   

3.
采用水浴浸提火龙果果皮红色素,通过单因素和正交试验研究浸提液乙醇浓度、pH值、水提温度和水提时间对火龙果果皮红色素提取效果的影响。结果表明,影响火龙果果皮红色素提取的主要因素及次序为:浸提温度、提取液浓度、pH值、浸提时间。试验范围内,火龙果果皮红色素最佳提取工艺条件为:浸提温度30℃、浸提时间45 min、pH值为6.5和乙醇浓度40%。  相似文献   

4.
采用溶媒法,以花生壳为原料、氯乙酸为改性剂制备了羧甲基化改性花生壳吸附剂,研究了其对废水中NH4+-N的去除效果,探讨了吸附时间、溶液pH值、改性花生壳用量、温度等因素对NH4+-N吸附效果的影响。结果表明,20g花生壳粉末在200mL 10%NaOH溶液中碱化2h后,和8g氯乙酸在500mL 90%酒精溶液中,恒温水浴45℃搅拌反应2h,水洗干燥后得到羧甲基化改性花生壳粉末,用此改性的花生壳处理50mg/L NH4+-N溶液的最佳条件为:在羧甲基化改性花生壳加入量10g/L,温度25℃,吸附时间1h,pH值8.0的条件下,花生壳对浓度为50mg/L的氨氮模拟废水的去除率可达72.1%。  相似文献   

5.
普洱茶主要氧化产物提取条件的优化及其抗氧化活性分析   总被引:1,自引:0,他引:1  
以普洱茶为原料,研究溶剂pH值、浸提温度、时间、料液比对茶褐素(TBS)提取率的影响。结果表明,溶剂pH值、浸提温度、时间、料液比等都显著影响TBS的浸提效果,其中料液比、浸提温度、浸提时问达到了极显著水平,各因素影响效果的重要眭依次为:料液比〉浸提温度〉浸提时间〉溶剂pH值。同时得到茶褐素浸提的优化条件为:温度100℃,溶剂pH=7,料液比1:30,时间20min。茶褐素抗氧化活性分析结果显示,其抗氧化活性优于普洱茶水提物。  相似文献   

6.
几种中草药提取物保鲜槟榔的研究   总被引:4,自引:0,他引:4  
选用生姜和大蒜的水溶物,海南血桐、猪肚木、海南椴、青梅等中草药的提取物,以及水溶性壳聚糖浸果,通过测定槟榔好果率、失重率、pH值及Vc含量、总糖含量变化,研究中草药提取液对槟榔果实的保鲜效果.结果表明,血桐提取物对槟榔有显著的保鲜效果,在同等条件相同存放时间下,用血桐提取液涂膜并密封存放的槟榔好果率最高,各测定值随存放时间的变化最小.  相似文献   

7.
 研究不同条件下壳聚糖对棉子萌发及幼苗生长的影响,可为生产实践提供理论依据和技术支持。以棉花种子和幼苗为试材,用不同条件(浸泡时间、pH、温度)下的壳聚糖溶液浸泡棉花种子,室温培养9 d,每天自然光照8 h。结果表明,棉花种子发芽率、发芽势、萌发指数、活力指数及α 淀粉酶活性、过氧化物酶活性和过氧化氢酶活性均随着处理时间的的延长先升高后降低;偏酸性条件较适宜种子萌发和幼苗生长,中性和偏碱性条件则起一定的抑制作用;高温可提高种子活力和幼苗生理生化指标,以处理时间12 h、pH 6~6.5、温度30 ℃效果最佳。  相似文献   

8.
改性花生壳处理废水中Cr^6+的实验研究   总被引:2,自引:0,他引:2  
简述了农林废弃物处理废水中重金属离子的研究现状,实验研究了改性花生壳对废水中Cr6 的去除效果,并探讨了溶液的pH值、Cr6 初始浓度、吸附时间、温度及改性花生壳用量等因素对Cr6 吸附效果的影响.结果表明,改性花生壳对Cr6 有很好的吸附作用,在温度33℃,改性花生壳用量1.0 g,20 mg·L-1的Cr6 溶液50 mL,溶液的pH值2.0,振荡吸附120 min的条件下,Cr6 的吸附去除率达到了98.4%.  相似文献   

9.
试验以福建水仙毛净茶为材料,设温度(110、120、130、140、150℃)、时间(1、3、5、7、9、11、13 h)2因素进行烘焙处理。结果表明:不同处理游离氨基酸总量在1.52%~2.33%,茶汤pH值在5.19~5.39,均低于对照;相同时间,温度越高,游离氨基酸总量和pH值越低;还原糖在17.1%~21.7%,变化规律不明显。对茶汤pH值进一步方差分析表明,不同处理茶汤pH值均极显著低于对照;相同温度不同时间,低温(110℃、120℃)pH值差异达极显著,中温(130℃)、高温(140℃、150℃)差异不显著;相同时间不同温度间差异极显著。烘焙影响茶汤风味,烘焙后茶汤pH值在5.23~5.28间,火功为中火时,茶汤呈酸味,其呈酸物质有待进一步分析。  相似文献   

10.
为有效降低蔗汁在常规清净过程中,因加热造成颜色加深、可溶性非糖杂质增加等给后续加工带来的不良影响,以壳聚糖、活性炭为材料,对蔗汁进行室温下的脱色研究。结果显示,壳聚糖的添加量仅为0.05%(g/m L)时,蔗汁中即可发生瞬间絮凝,且吸附絮凝作用有59.4%的脱色率,当协同1 g活性炭,对5000 IU~17000 IU的甘蔗蔗汁进行脱色,总脱色率平均达到96.7%,加入活性炭后总脱色率平均提高了37.3%,清汁重力纯度平均提高了3.41%,由此可证明仅室温下,壳聚糖-活性炭协同对甘蔗蔗汁具有很好的清净、脱色能力。  相似文献   

11.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

12.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

13.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

14.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

15.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

16.
Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.  相似文献   

17.
Pasture legumes are important components of both mixed farming rotations and permanent pastures in temperate climates. Breeding of two widely sown pasture legumes, subterranean clover (Trifolium subterraneum L.) and French serradella (Ornithopus sativus Brot.), is constrained by the long generation cycle, typically enabling only one generation per year. We hypothesized manipulation of culture medium and conditions would enable the development of a laboratory‐based protocol for in vitro reproduction in subterranean clover and French serradella. In vitro flowering and viable seed set was induced from both species. For subterranean clover, the most effective treatment was culturing on modified MS medium with 1 μm kinetin and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and continuous photoperiod. For French serradella, culture on a hormone‐free B5 medium with 5 mm NH4Cl and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and 20 h photoperiod was optimum. It is expected this technique will have application in accelerating generation turnover within breeding programs, for the study of factors influencing flowering in pasture legumes, and for the propagation of valuable yet enfeebled plants such as embryo‐rescued hybrids.  相似文献   

18.
Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells.  相似文献   

19.
Evaluation of crop and forage yield stability is of increasing relevance in the context of current and recent environmental changes but, in contrast to other field crops, there are no published systematic analyses among forage crops in Europe. A study of stability performance was conducted with 13 Czech cultivars of lucerne at four locations over a 2‐year period with the following aims: (a) to evaluate yield stability of varieties across different environments and (b) to calculate measurable benefits of variety selection in relation to the specific environment. The cultivar Vlasta was identified as the highest yielding cultivar (annual yield 16.0 t DM/ha), whereas the lowest yielding cv. Magda, Tereza and Oslava averaged around 14.9 t DM/ha. Effect of genotype × environment interaction (G × E) was two times higher than for genotype alone. Additive main effects and the multiplicative interaction (AMMI) model showed that the highest yielding cultivars may not be stable across environments. This study demonstrated further that significant yield improvement could be detected, even among a relatively homogenous group of domestic cultivars, and this was driven mainly by site productivity: the improvement was +10% in low‐yielding sites, compared with +3% in high‐yielding sites. Results highlight that advanced agronomy should also consider stability parameters such as AMMI stability value or superiority measures for forage crops in response to the challenges associated with climate change.  相似文献   

20.
Summary Morphological and biochemical parameters that could be involved in resistance to late blight were studied in non-infected and in infected potato hybrids resulting from a cross betweenSolanum phureja, resistant toPhytophthora infestans, and a susceptibleSolanum tuberosum. Some morphological differences between resistant and susceptible hybrids, indicating a positive correlation between stem diameter and phloem thickness in the stem and resistance toP. infestans, were observed. The lignin content in the leaves of the resistant hybrid rose upon infection byP. infestans. In the leaves of the susceptible hybrid, a diminution of the lignin content could be observed upon infection byP. infestans. In the same context, peroxidasic activity raised upon infection byP. infestans in both resistant and susceptible hybrids. Further characterization of the hybrid clones based on the polymorphism of peroxidases was attempted using isoelectric focusing.  相似文献   

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