【摘要】：南極細(xì)菌長期生活在酷寒、強輻射的極端環(huán)境中,因而形成了獨特的生理生化特征,進(jìn)化出與眾不同的極端環(huán)境適應(yīng)機制。胞外多糖(exopolysaccharide, EPS)是微生物在生長代謝過程中產(chǎn)生的、且分泌到胞外的可溶性多糖及多糖復(fù)合物,在細(xì)胞間信息交換、細(xì)胞保護、細(xì)胞粘附和環(huán)境適應(yīng)性等方面具有重要作用。由于極端環(huán)境中的EPS所具有的獨特的生物活性使其在食品加工、新藥研發(fā)和新型飼料開發(fā)等方面具有非常重大的應(yīng)用潛力。研究了在基礎(chǔ)飼料中添加不同含量(0、0.5、1.0、1.5和2.0 g/kg)南極細(xì)菌Pseudoalteromonas sp.3-3-1-2產(chǎn) EPS對黃蓋鰈(Pseudopleuronectes yokohamae)生長和免疫活性的影響。結(jié)果表明,當(dāng)基礎(chǔ)飼料中EPS添加量為1.5 g/kg時,試驗組黃蓋鰈的體重和體長均高于對照組,呈顯著性差異(P0.05)。添加量為1.0和1.5 g/kg試驗組的脾臟和后腸淋巴細(xì)胞呼吸爆發(fā)能力和對照組相比有明顯提高,呈極顯著性差異(P0.01)；脾臟淋巴細(xì)胞增殖能力也有明顯提高,呈顯著性差異(P0.05)。和對照組相比,添加量為1.5 g/kg試驗組的脾臟蛋白含量明顯提高,呈顯著性差異(P0.05)；脾臟和肝臟酸性磷酸酶(ACP)活力明顯提高,呈顯著性差異(P0.05)。添加量為1.5和2.0 g/kg試驗組的肝臟蛋白含量和總超氧化物歧化酶(T-SOD)活力明顯提高,呈顯著差異(P0.05)。攻毒實驗表明,試驗組黃蓋鰈均獲得了一定的免疫保護,且添加量為1.5 g/kg試驗組的免疫保護率最高(50.0%)。由此得出,在基礎(chǔ)飼料中添加南極細(xì)菌Pseudoalteromonas sp.3-3-1-2產(chǎn)EPS可促進(jìn)黃蓋鰈生長,提高特異性免疫活力和非特異性免疫活力,提高黃蓋鰈抗病能力,且添加量以1.5 g/kg效果最佳。利用單因子試驗和響應(yīng)面法對南極細(xì)菌Pseudoalteromonas sp.3-3-1-2產(chǎn)胞外多糖條件進(jìn)行了優(yōu)化。單因子試驗表明,菌株3-3-1-2產(chǎn)胞外多糖的最佳碳源和氮源分別為蔗糖和硝酸鉀,其最佳添加量分別為4%和1%；最適培養(yǎng)溫度為15℃；最佳培養(yǎng)基鹽度和初始pH分別為45和9；對產(chǎn)糖有顯著影響的單因素為碳源(蔗糖)、氮源(KN03)和溫度。通過Box-Behnken試驗設(shè)計和Design-Expert響應(yīng)面對上述因素進(jìn)行分析,確定優(yōu)化的菌株3-3-1-2產(chǎn)胞外多糖的發(fā)酵條件為：蔗糖43.1 g/L、硝酸鉀9.6 g/L和溫度17℃；經(jīng)條件優(yōu)化后菌株3-3-1-2發(fā)酵液的粗胞外多糖產(chǎn)量可達(dá)3.15 g/L。對菌株P(guān)seudoalteromonas sp.3-3-1-2產(chǎn)EPS進(jìn)行了DEAE Sepharose fastflow和G-50的初步分離純化,對獲得的較純成分EPS-1進(jìn)行進(jìn)一步的純度鑒定和分子量的測定,并對其進(jìn)行了單糖組分分析,以期獲得其多糖分子結(jié)構(gòu)。
[Abstract]:Extracellular polysaccharides (EPS) are produced by microorganisms in the process of growth and metabolism, and secrete extracellular soluble polysaccharides and polysaccharide complexes in fine grains. Intercellular information exchange, cell protection, cell adhesion and environmental adaptability play an important role. EPS in extreme environments has great potential applications in food processing, new drug research and development and new feed development due to its unique biological activities. The effects of EPS production by Antarctic bacteria Pseudoalteromonas sp.3-3-1-2 on the growth and immune activity of Pseudopleuronectes yokohamae were studied. The results showed that the body weight and length of flatfish in the experimental group were significantly higher than those in the control group (P 0.05) when the EPS content in the basal diet was 1.5 g/kg. Compared with the control group, the spleen and hind intestine lymphocyte respiratory burst ability and the spleen lymphocyte proliferative ability of the 5 g/kg test group were significantly improved (P 0.01), and the spleen lymphocyte proliferative ability was significantly improved (P 0.05). Compared with the control group, the spleen protein content of the 1.5 g/kg test group was significantly increased. The content of liver protein and the activity of total superoxide dismutase (T-SOD) in the 1.5 and 2.0 g/kg groups were significantly higher than those in the control group (P 0.05). It was concluded that the addition of Antarctic bacteria Pseudoalteromonas sp.3-3-1-2 to the basic diet could promote the growth of flatfish, enhance the specific and non-specific immune activities, and enhance the disease resistance of flatfish, and the dosage of 1.5 g/kg was the best. The optimum conditions for producing extracellular polysaccharides by Antarctic bacteria Pseudoalteromonas sp.3-3-1-2 were studied by single factor test and response surface methodology. The optimum fermentation conditions for exopolysaccharide production of strain 3-3-1-2 were determined as follows: sucrose 43.1 g/L, potassium nitrate 9.6 g/L and temperature 17, respectively. The crude exopolysaccharide yield of strain 3-3-1-2 fermentation broth could reach 3.15 g/L after optimized conditions. The EPS produced by strain Pseudoalteromonas sp.3-3-1-2 was purified by DEAE Sepharose fastflow and G-50. The purity and molecular weight of the purified EPS-1 were further identified and determined. In order to obtain the molecular structure of polysaccharides.
【學(xué)位授予單位】：山東大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：S816

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 劉存歧,王偉偉,張亞娟;水生生物超氧化物歧化酶的酶學(xué)研究進(jìn)展[J];水產(chǎn)科學(xué);2005年11期

2 劉紅柏;盧彤巖;張春燕;孫大江;白秀娟;;黃芪對史氏鱘抗氧化能力及免疫力的影響[J];大連水產(chǎn)學(xué)院學(xué)報;2006年03期

3 許國煥,梁友光,吳月嫦,何四旺,陳崗;酵母葡聚糖對南美白對蝦免疫功能的影響[J];飼料工業(yè);2003年10期

4 謝荔朋;;微生物胞外多糖對養(yǎng)殖動物的免疫增強作用[J];福建畜牧獸醫(yī);2006年01期

5 李鐵林;吳昌賢;張燕霞;;糖和糖醇的氣相色譜分析研究Ⅱ.糖腈乙酰酯衍生物氣相色譜分析的改進(jìn)[J];分析化學(xué);1982年05期

6 盛家榮,曾令輝,翟春,陳超球;多糖的提取、分離及結(jié)構(gòu)分析[J];廣西師院學(xué)報(自然科學(xué)版);1999年04期

7 黃卉,王弘,劉欣;多糖的構(gòu)效關(guān)系研究進(jìn)展[J];廣州食品工業(yè)科技;2004年03期

8 芮海云,吳國榮,陸長梅;多糖類生物活性的研究在醫(yī)藥領(lǐng)域的應(yīng)用[J];淮陰師范學(xué)院學(xué)報(自然科學(xué)版);2002年03期

9 付海寧;趙峽;于廣利;陳娥功;文松松;;鹽藻多糖單糖組成分析的四種色譜方法比較[J];中國海洋藥物;2008年04期

10 陳皓文;高愛國;;中國極地微生物學(xué)調(diào)查研究進(jìn)展[J];極地研究;2005年04期

，

本文編號：2242465