Influence of osmotic pressure on somatic embryo maturation in Pinus densiflora

The effect of an osmoticum, polyethylene glycol (PEG), on somatic embryo production was examined using embryogenic cells of Pinus densiflora. In the basal medium containing 30 μM abscisic acid and 6% maltose, the quality of the embryos formed was poor even though somatic embryos were produced. The addition of PEG with molecular weight of 4000 or 8000 significantly enhanced the development of both the quality and quantity of somatic embryos. Furthermore, higher levels of a constant osmotic pressure with PEG 8000 in a range from about 300 to 450 mmol/kg could remarkably enhance the morphogenesis of somatic embryos and their number of embryos produced. A higher stable osmotic pressure with an appropriate molecular weight of PEG is a key factor for the production of good quality somatic embryos in P. densiflora.     

Preparation of amphiphilic lignin derivative as a cellulase stabilizer

A polymeric amphiphile, PE-AL, was prepared from acetic acid lignin (AL) obtained by acetic acid pulping of birch under atmospheric pressure with polyethylene glycol diglycidyl ether (PE) as the crosslinker. The behavior of PE-AL solutions and the complex formation of PE-AL with protein were investigated to clarify the function of this novel lignin derivative. The reduced viscosity of the amphiphile in aqueous solution was low (<0.3dl/g), and it decreased with increasing concentration in dilute solution. This suggested that the PE-AL in aqueous solution has a structure similar to that of Einstein's sphere and shrinks upon hydrophobic interaction among the structural moieties in AL and the exclusive volume effect. The amphiphilic PE-AL obviously formed a complex with bovine serum albumin (BSA) at 4°C with a reaction time of about 1 week. After complex formation with cellulase for 1 week, the cellulase activity of the resulting complex is significantly enhanced and is preserved after recycling the complex for hydrolysis of cellulosic materials several times.Part of this work was presented at the 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998     

聚乙二醇和高温热处理复合改性对杨木吸水性的影响

木材易吸水、尺寸稳定性差等缺陷严重限制了其应用,通过聚乙二醇浸渍、热处理改性可以改善这些不足。通过采用3种不同分子量的聚乙二醇(PEG1000、PEG2000、PEG4000)对杨木进行预处理,然后在不同温度条件下(120℃、140℃、160℃、180℃、200℃)进行热处理,研究不同条件复合处理对杨木试材吸水性的影响。试验表明,热处理可以改善试件初期的吸水性能,PEG浸渍处理则能抑制试件长期吸水,通过复合改性处理可以达到同时控制试件短期和长期水分吸收的目的。     

The effect of tannic acid and polyethylene glycol on the absorption capacity of chicken intestine for d-xylose and β-carotene

In an experiment, the possible influence of tannic acid (TA) and polyethylene glycol (PEG) on the absorption capacity of intestine for d-xylose and β-carotene in broiler chicken was investigated. Four groups of nine 28-day-old broiler cockerels received d-xylose (500 mg) and β-carotene (52 μg) solutions (Group 1 to 4) with TA (1 g, Group 2 to 4) and PEG (500 mg Group 3 and 1 g Group 4), orally. One blood sample prior to, and four others after the administration of test materials, were collected from wing vein on 40 min basis, for 160 min and the concentration of plasma d-xylose was determined. The concentration of β-carotene was also measured in plasma of blood samples taken prior to and 160 min post-administration of the test materials. Plasma d-xylose concentration of all groups showed quadratic correlations with time (p < 0.001, r(2) = 0.84, 0.60, 0.70 and 0.74 for Group 1 to 4, respectively). Administration of TA reduced the plasma concentration of d-xylose in Group 2. However, feeding PEG after TA raised the concentration of d-xylose in Group 4 to the level that there was no difference in that variable between this group and Group 1. Although the plasma concentration of β-carotene was increased in 160 min post-ingestion of the test material, no difference was found in that variable among the experimental groups. In conclusion, TA and its interaction with PEG have impacts on the absorption capacity of intestine for d-xylose and highly likely other simple sugars, but TA or PEG have no influence on the absorption of β-carotene and most probably other fat soluble vitamins.     

外源甜菜碱对渗透胁迫下小桐子幼苗生物膜伤害的缓解效应

由于小桐子种子具有较高的含油量,因此被认为是最重要的能源植物之一。利用外源甜菜碱对小桐子种子和幼苗进行浸种或灌根处理,结果发现,外源甜菜碱浸种或灌根处理都可提高幼苗茎和叶中内源的甜菜碱含量,缓解PEG胁迫下小桐子幼苗根、茎和叶中的丙二醛积累以及电解质渗漏率的增加,暗示外源甜菜碱处理对生物膜伤害的缓解效应可能与内源甜菜碱含量的提高有关。     

聚乙二醇硫酸铵沉淀法对不同亚类单克隆抗体活性的影响

比较了以聚乙二醇和硫酸铵两种沉淀方法分离纯化腹水中单克隆抗体后,对不同亚类单克隆抗体活性的影响。结果表明,经３３％的硫酸铵沉淀腹水ＩｇＧ时,对其活性没有明显影响;沉淀ＩｇＭ时其活性明显降低。以聚乙二醇进行沉淀,对腹水单克隆抗体ＩｇＧ和ＩｇＭ活性均无明显影响,但依不同亚类的单克隆抗体,所选用的聚乙二醇浓度不同,对于ＩｇＧ,以１５％聚乙二醇沉淀较为合适,而沉淀ＩｇＭ时,则以６％聚乙二醇较为合适。     

水貂循环免疫复合物检测方法的建立及应用

本试验建立了检测水貂循环免疫复合物(CIC)的微量PEG沉淀比浊法和固相C_(1q)—SPA—ELISA.用这两种方法检测了38例健康水貂血清、126例阿留申病(AD)病貂血清.微量PEG沉淀比浊法的结果(OD值,(?)±S)为:健康水貂0.081±0.042,AD病貂0.198±0.066;固相C_(1q)—SPA—ELISA的结果(OD值,(?)±S)为:健康水貂0.245±0.057,AD病貂0.503±0.167,敏感性为0.25μg/mL.经统计学处理,健康水貂与AD病貂血清OD值之间呈极显著差异(P<0.01),表明水貂阿留申病的病理过程与CTC有关.建立的两种方法均具有快速、简便、重复性好和敏感性高等特点,两种方法的相关性显著.     

PEG-6000引发对白羊草种子发芽的影响

为了探讨PEG-6000溶液引发对白羊草种子萌发的影响,采用水势0、-0.2、-0.4和-0.6Mpa的聚乙二醇溶液对白羊草种子进行引发0、3、6和9 h处理,测定白羊草种子的发芽率和发芽势,并计算其发芽指数、活力指数、平均发芽天数和发芽速率系数。试验结果表明:(1)水势为-0.6 Mpa的PEG-6000溶液引发可以有效的提高白羊草种子的发芽速度系数至0.387,显著高于其他水势处理(P<0.05),并且在此水势处理下,引发3 h的发芽速度系数显著高于其他处理(P<0.05);(2)不同引发时间均可以显著提高白羊草种子的发芽能力(P<0.05),引发6 h比引发3 h和9 h的白羊草种子发芽能力高,但差异不显著。     

四种常见家禽血清免疫复合物的初步研究

采用2%和3.5%聚乙二醇(PEG)沉淀法对麻鸭、土鸡、乌鸡、鸽子四种常见家禽的血清免疫复合物进行含量测定,并采用SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)对其进行初步分析。结果表明,免疫复合物含量在同一种家禽的不同PEG浓度处理间均有显著差异;不同家禽间的同一PEG浓度处理间也均有显著差异。电泳图谱表明,四种家禽血清免疫复合物的电泳条带有一定差异,而同属鸡形目的土鸡和乌鸡之间的条带差异较小。