The bacterial flora and their possible association with spoilage in a variety of fresh-water fish: Cyprinus carpio. var. communis

The bacteria from a variety of fresh-water fish, Cyprinus carpio. var. communis, showed the presence of micrococci, Gram positive and Gram negative rods. These have been characterized as far as was possible. Of thirty-eight strains of bacteria used, only six strains were considered as causing spoilage of fish flesh in experiments where flesh was incubated with individual cultures of the bacteria. These six strains had been found on the surface and/or intestine of the fish and support the suggestions that, after death, invasion of flesh by bacteria from the surface and intestine could be the cause of bacterial spoilage of fish.

高山植物唐古特红景天（Rhodiola algida Var.tangutica）抗冻蛋白的研究

抗冻蛋白（AFP）或热滞蛋白（THP）最早是从极区鱼和昆虫中发现的一类特殊蛋白质，其共同特性是能阻止体液内冰核的形成和生长，降低体液的冰点，使其冰点低于熔点（热滞效应）。近几年的研究表明，AFP在某些植物、细菌、真菌中也存在。生长在极端低温环境中的高山植物体内是否也存在AFP，据我们掌握的资料，还未见这方面的报道。为此，我们选择了青海高原海拔4000米高山生长的唐古特红景天为实验材料，并在这种植物中发现了抗冻蛋白。主要实验结果概括如下： 1. 唐古特红景天叶片有很强的抗冻性，可耐受-26.5 ℃的冰冻温胁迫。在北京地区夏季（7月）驯化20天后，半致死温度（LT_(50)）升高为-15.5 ℃。叶片质外体蛋白抽提液有明显的热滞效应（0.2 ℃），在AFP中存在糖基。SDS-PAGE分析表明，质外体AFP为分子量在43-85KD范围内的五条多肽。 2. 光镜组织化学切片显示，在红景天叶片中存在蛋白质量丰富的细胞;电镜细胞化学研究揭示，在细胞壁外层及细胞间隙中分布着明显的经钌红特异染色的糖蛋白，这种糖蛋白因环境温度升高而减少。结合前述的实验结果，确认这种细胞壁外层及细胞间隙中的糖蛋白，即抗冻蛋白。 3. 以唐古特红景天叶片为外植体，在MS+BA_2+NAA_(0.2)固体培养基上可诱导出黄绿色，松脆愈伤组织。愈伤组织细胞在同样成分的液体培养基中培养获得成功。在悬浮培养液中可检测到分泌蛋白的存在。经SDS-PAGE分析表明，经低温锻炼或ABA诱导后，细胞分泌蛋白的多肽谱带数增加。与此相对应的是，细胞的抗冻能力也明显提高。PAS染色揭示，多肽中均含有糖基。 4. 通过测定热滞值，确信细胞分泌蛋白是具有抗冻活性的糖蛋白。

Toxicity of copper sulphate on some haematological parameters of a freshwater teleost Cyprinus carpio var. communis

Haematological changes in a freshwater teleost, Cyprinus carpio var. communis, exposed to acute and sublethal toxicity of copper sulphate were studied. During the acute treatment, erythrocyte and leucocyte count, and haemoglobin content increased, whereas during the sublethal treatment, erythrocyte count and haemoglobin content decreased and leucocyte count increased.

Responses of plasma transaminase activity in Cyprinus carpio var. communis to mercury toxicity

The present study reports the behavioural and enzymological responses in a freshwater teleost fish, Cyprinus carpio var. communis, exposed to acute and sublethal toxicities of mercuric chloride. During acute treatment, significant behavioural changes like erratic swimming, excess mucus secretion and increased opercular movements were noticed. During acute and sublethal treatments, both aspartate amino transferase and alanine amino transferase activity increased throughout the study period. Comparing the treatments, the changes in enzyme activities were found high in acute treatment and all the values were significant at 5% level. The above findings can be used as non-specific biomarkers of environmental pollutants.

Responses of Cyprinus carpio var. communis to Cyhalothrin, a pyrethroid insecticide

Haematological and biochemical profiles in a freshwater teleost, Cyprinus carpio var. communis, exposed to sub-lethal toxicity of the insecticide cyhalothrin were studied. During the treatment, erythrocyte count, haemoglobin content and protein content decreased, whereas leucocyte count and glucose level increased. The data are discussed in relation to the significance of haematological and biochemical changes as non-specific biomarkers against anthropogenic stress.

One new flavanoid and Anti-HIV active constituents from boussingaultia gracilis miers var. pseudobaselloides bailey

Boussingaultia gracilis Miers var. pseudobaselloides Bailey (Basellaccae) is a folk medicine used as an analgesic and supplements, only a few research was reported on the chemical constituents of this plant. This paper presented its chemical and anti-HIV

Lignans with Anti-HIV Activity from Schisandra propinqua var. sinensis

Fourteen new lignans, tiegusanins A-N (1-14), together with 13 known compounds were isolated from the aerial parts of Schisandra propinqua var. sinensis. The structures and absolute configurations of 1-13 were established using a combination of spectrosco

Effect of high dietary starch levels on the growth performance, blood chemistry and body composition of gibel carp (Carassius auratus var. gibelio)

An 8-week growth trial was carried out in a semi-recirculation system to investigate the effect of high dietary starch levels on the growth performance, blood chemistry, starch utilization and body composition of gibel carp (Carassius auratus var. gibelio). Five isonitrogenous and isocarloric experimental diets were formulated to contain different starch levels (24%, 28%, 32%, 36% and 40% respectively). Triplicate groups of fish (24 fish per tank with an average body weight, of 8.5 g) were assigned to each diet. The results showed that dietary carbohydrate levels significantly affected the growth performance, hepatopancreatic lipid content, pyruvate kinase (PK) activity and whole-body lipid content. Growth performance, body crude lipid and plasma glucose concentrations showed a decreasing trend with an increase in dietary starch from 24% to 40%. Pyruvate kinase activities and hepatopancreatic lipid content showed an increasing trend with the dietary starch increasing from 24% to 32%, and then a decreasing trend with the dietary starch increasing from 32% to 40%. No significant difference in the hepatopancreatic hexokinase (HK) activity, plasma triglyceride contents, body crude protein, ash and calcium (Ca) and phosphorus (P) contents was observed between different treatments. In conclusion, higher dietary starch levels (32-40%) significantly (P < 0.05) decreased the growth of gibel carp in the present study.