微波提取葛仙米多糖及其抑癌作用研究

[目的]为葛仙米的药用和食用价值研发提供科学依据和理论参考。[方法]通过微波辅助法优化葛仙米多糖提取工艺,并采用MTT法对葛仙米多糖的抑癌活性进行研究。[结果]葛仙米多糖的最佳提取条件为微波功率450 W,微波辐射时间3 min,料水比1∶10g/ml,多糖得率9.1%。随着葛仙米水提液浓度的升高,对HCT-116细胞增殖抑制率不断增强,对HCT-116细胞生长抑制的IC50为18mg/ml。[结论]微波辅助提取葛仙米多糖工艺合理可信,且葛仙米多糖对HCT-116细胞的增殖具有较好的抑制作用,抑癌功效突出。     

田间合理施用尿素防止野生葛仙米减产的研究

分析了尿素的负效应葛仙米对尿素的敏感性,并介绍了尿素产品、特点及使用,提出了在葛仙米产区合理使用尿素为高产野生葛仙米生产服务的想法。     

Absorption of color additives and settling volume in water of blue-green alga,ishikurage (Nostoc commune)

The properties of ishikurage (Nostoc commune) and other algae were compared. Ishikurage and suizenji nori (Aphanothece sacrum) absorbed much more amaranth than others. They have a high settling volume (SV) in water. The high SV of ishikurage is attributable to its neutral detergent fiber (NDF). The acid detergent fiber (ADF) from the alga had a high amaranth absorption. However the absorption by the ADF did not explain the absorption by ishikurage.The results suggest that ishikurage may have a nutritional significance as a source of dietary fiber.     

Changes in aggregate stability,nutrient status,indigenous microbial populations,and seedling emergence,following inoculation of soil withNostoc muscorum

The potential of the N₂-fixing cyanophyteNostoc muscorum for improving the aggregate stability of a poorly structured silt loam soil was studied in a greenhouse experiment. Inoculum rates were 1.61×10⁵ cells g^-1 soil dry weight (low rate) and 4.04×10⁵ cell g^-1 soil dry weight (high rate), approximately equivalent to a field application of 2 and 5 kg ha^-1 cells dry weight, respectively.N. muscorum numbers had increased 8-fold (low rate) and 10-fold (high rate) by 300 days after inoculation, indicating not only survival but proliferation. Increases in soil polysaccharides, determined as soil carbohydrate C, were 2.96–3.49 time the values in the non-inoculated soils and aggregate stability had incrased by an average of 18% on day 300. Inoculation withN. muscorum also had a pronounced effect on soil chemical and biological properties, with total C increasing by 50–63% and total N increasing by 111–120%. Increases in the soil indigenous microbial population were recorded, with numbers of bacteria 500, fungi 16, and actinomycetes 48 times the non-inoculated values on day 300 in the high-rate soil. The emergence of lettuce seedlings (Lactuca sativa var. Saladin) in undisturbed inoculated 300-day soils was 56% (low rate) and 52% (high rate) higher than in non-inoculated soils. However, homogenising soils and irrigating (to smulate ploughing and surface crusting) significantly reduced this increase in both treatments, although emergence in inoculated soils was still greater by 45% (low) and 24% (high). It is recommended that inoculated soils be left undisturbed prior to planting. The effects ofN. muscorum on soil physical, chemical, and biological properties indicate the possible benefits of cyanobacteria as soil inoculants, not only for the improvement of soil aggregate stability but also as a means of improving seedling emergence.     

超声提取地木耳中多糖动力学及热力学分析

为优化地木耳多糖提取途径,以超声波辅助提取地木耳中的多糖,对其提取过程的动力学及相关热力学进行了研究。探讨了料液比、功率和温度对多糖提取过程的影响,并对其动力学模型进行了验证;通过Arrhenius方程计算多糖提取过程的活化能Ea及热力学参数ΔH、ΔS和ΔG。结果表明:动力学模型能够很好地描述多糖的超声波提取过程,提取过程的活化能Ea=86.59 kJ/mol,指前因子A=2.320 3 mL/(mg·min);地木耳多糖超声提取过程中的热力学参数ΔH、ΔS均大于0,表明该提取过程是一个吸热熵增加的过程;ΔG0,说明操作温度下多糖的提取过程是一个自发过程。     

地木耳对环境因子的响应研究

指出了环境因子是生命活动的重要限制因子,对生物有机体的生长发育和生理代谢具有明显的影响。对地木耳生长的环境和其分布区土壤pH值、有机质、全氮、全磷、速效磷和速效钾含量进行了研究,结果表明:地木耳适宜生存于温度和湿度较高、通气性较差的微环境中,其生长需要充足的水分,但不宜水渍;地木耳对土壤质地无特殊要求,适宜在中性至酸性和有机质含量较高的土壤中生长,而对土壤全氮、全磷、速效磷和速效钾的含量则无特殊要求。     

青海高原地木耳中氨基酸含量的主成分分析

[目的]对青海高原地木耳中氨基酸含量进行综合评价。[方法]采用SPSS统计软件,对青海高原5个地区的地木耳中氨基酸的含量进行主成分分析。[结果]结果表明,海南州地木耳中氨基酸的品质最好,黄南州的次之,海西州的最差。[结论]为今后青海高原地木耳开发利用提供科学依据。     

宁夏发菜分布区受损生态系统的生态修复研究

[目的]为发菜分布区受损生态系统生态修复提供理论依据。[方法]以宁夏青铜峡甘城子发菜分布区荒漠化草原为例,在植被调查和分析的基础上,通过定期人工给水研究发菜分布区受损生态系统的生态修复效果。[结果]通过定期人工给水、围栏育草等措施能够启动荒漠化草原的植被恢复过程,有效改善了土壤理化性质,提高了植被盖度、植被生物量、一年生和多年生草本植物的物种丰富度。[结论]研究结果对改进荒漠化草原治理技术具有指导意义。     

发状念珠藻POD和EST同工酶研究

[目的]通过分析野生的和液体培养的发状念珠藻的过氧化物酶（POD）和酯酶（EST）同工酶,了解其在遗传物质表达和生理代谢方面存在的差异。[方法]采用聚丙烯酰胺垂直电泳法对野生的和液体培养的发状念珠藻细胞的POD和EST同工酶进行分析与比较。[结果]POD同工酶谱分析表明,野生发状念珠藻细胞有4条带,其Rf值分别为0.400、0.709、0.764和0.929;液体培养的发状念珠藻细胞只有2条带,其Rf值分别为0.736和0.929。EST同工酶谱分析表明,野生发状念珠藻细胞有2条带,其Rf值为0.397和0.559;液体培养的发状念珠藻细胞有3条带,其Rf值分别为0.296、0.397和0.458。[结论]野生的与液体培养的发状念珠藻细胞在POD和EST电泳图谱上存在一定差异,以野生发状念珠藻的POD同工酶酶谱带数多,酶活性强。     

地耳和地衣的化学元素组成特点及其与放牧率的关系

本文研究放牧草原中地衣和地耳的化学元素组成特点,水溶性元素形态所占的比例以及地衣的元素含量与放牧率的关系。结果表明,地衣和地耳的Ｃ,Ｎ,Ｃａ含量较高;Ｐ,Ｍｇ,Ｋ,Ｆｅ,含量中等,Ｎａ,Ｍｎ,Ｃｕ,Ｚｎ,Ｂ含量较低。地耳中水溶性Ｎ占全Ｎ的２１％。放牧区Ｃ含量下降,Ｎ含量提高,Ｃ／Ｎ比在中牧和重牧区较低。