Hepatoprotective effect of Paecilomyces tenuipes polysaccharides on carbon tetrachloride -induced liver injury

AIM:To investigate the protective effect of crude Paecilomyces tenuipes polysaccharides (cPtPs) and Paecilomyces tenuipes polysaccharides (PtPs) in a rat model of acute hepatic necrosis induced by carbon tetrachloride (CCl4). METHODS:Wistar rats were divided into four groups (control group, CCl4 group, cPtPs+CCl4 group and PtPs +CCl4 group), the four groups were given intragastrically with normal saline, cPtPs and PtPs for 15 d, respectively. In the last two days, these groups except control group were injected peritoneally with CCl4. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) were detected by automatic biochemistry analyzer. Pathological changes of hepatic tissue were assessed by hematoxylin-eosine (HE) staining. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in liver homogenate were analyzed using xanthinoxidase and thio-barbituric acid, respectively. The concentration of Ca2+ in hepatocyte mitochondria was determined by colorimetric method. The expression of α-smooth muscle actin (α-SMA) was examined in hepatic tissue by immunohistochemical method. RESULTS:Compared with control group, serum levels of ALT, AST, TBIL, DBIL and IBIL in CCl4 group increased significantly, denaturation and necrosis implicated to the whole hepatic lobules. Compared with CCl4 group, serum levels of ALT, AST, TBIL, DBIL and IBIL in PtPs +CCl4 group decreased significantly, denaturation and necrosis located in the third region of hepatic lobules, the level of SOD increased and MDA decreased (P<0.05) in endochylema. Concentration of Ca2+ in mitochondria decreased in PtPs +CCl4 group and cPtPs +CCl4 group (P<0.05, P<0.01, respectively). Expression of α-SMA was found little in PtPs+CCl4 group. CONCLUSION:PtPs, the effect is better than cPtPs, lessens CCl4-induced hepatonecrosis significantly. The role may be related with anti-lipid peroxidation.     

猪肚菇粗多糖脱蛋白脱色工艺优化研究

以猪肚菇粗多糖为原料，对其脱蛋白和脱色工艺条件进行优化。采用蛋白酶法和sevag法联合除蛋白，研究不同酶添加量、处理温度、pH值和处理时间等因素对蛋白脱除率的影响，采用正交设计对工艺条件进行了优化。猪肚菇多糖脱色采用大孔吸附树脂，系统研究树脂静态吸附与动态吸附试验。结果表明：最佳脱蛋白工艺为：2 mg/mL猪肚菇粗多糖溶液，木瓜蛋白酶用量1 mg，酶解温度60 ℃，酶解pH值5.5，酶解时间5 h，sevag试剂处理2次，猪肚菇多糖蛋白质脱除率和多糖损失率分别为85.18％和23.41％；最佳脱色工艺为：选用NKA-9树脂脱色，静态吸附时树脂用量1 ∶ 10，时间5 h，温度30 ℃，动态吸附时pH6.0，洗脱速率3 BV/h，猪肚菇多糖脱色率和多糖损失率分别为84.19％和20.79％。     

Composition and molecular structure of polysaccharides released from barley endosperm cell walls by sequential extraction with water,malt enzymes,and alkali

Isolated and purified endosperm cell walls (CW), used in this study, were derived from a Canadian malting barley variety, AC Metcalfe, grown in three different environments in Canada in 2003, and varying in grain protein and β-glucan contents, as well as in grain hardness. The CW were initially extracted with water at 45 °C and subsequently digested with barley malt crude enzyme extract resulting in two fractions designated CW-WE45 and CW-MD, respectively. The remaining non-digested cell wall material (CW_ND) was further fractionated by sequential extraction with water at 95 °C (CW_ND-WE95), saturated barium hydroxide (CW_ND-BaE), and 1 N sodium hydroxide (CW_ND-NaE) at 25 °C. Composition and molecular structure analyses were carried out for all fractions including the remaining cell wall residue (CW_RES). Extraction of CW with water followed by digestion with malt crude enzyme extract solubilized the majority of β-glucans (∼55–70%) and glucomannans (∼60–80%) but only a small portion of arabinoxylans (∼20–30%) present in the intact CW. The CW-WE45 and CW_ND-WE95 fractions consisted mostly of β-glucans exhibiting high average molecular weights (M_w) (2–3 × 10⁶), whereas the CW_ND-BaE consisted mainly of arabinoxylans with M_w about 1–1.5 × 10⁶. The CW_ND-NaE contained almost equal amounts of β-glucans and arabinoxylans and a small amount of glucomannans, whereas the CW_RES contained approximately equal proportions of β-glucans, arabinoxylans and glucomannans. β-Glucans in CW_ND-WE95, CW_ND-NaE, and CW_RES exhibited a higher ratio of 3-O-β-d-cellobiosyl-d-glucose to 3-O-β-d-cellotriosyl-d-glucose (DP3/DP4) compared to β-glucans in CW-WE45 and CW-MD. β-Glucans in CW_ND-NaE showed the highest level of long cellulosic oligosaccharides with DP ≥ 5, whereas those in the CW_RES had the highest DP3/DP4 ratio. The CW-MD was fractionated by ultrafiltration into high (CW-MD_HMW) and low-molecular weight (CW-MD_LMW) sub-fractions, with weight-average M_w of ∼150–350 × 10³ and <10 × 10³, respectively, as confirmed by size-exclusion chromatography. The monosaccharide composition of the sub-fractions indicated a more extended enzymic degradation of β-glucans and glucomannans than arabinoxylans. Some differences in composition and molecular structure of the cell wall constituents among the three barley samples were related to their solubility and enzymic digestibility.     

桑叶多糖的提取工艺研究

[目的]优选桑叶多糖的最佳提取工艺。[方法]分别用热水浸提法和水提醇沉法、超声波辅助法3种方法提取桑叶多糖,以多糖的得率为指标,优选出最佳提取工艺。[结果]热水浸提法提取桑叶多糖的较优条件为温度80℃、时间1.5 h、料液比1∶40（g/ml）;在此条件下,桑叶多糖得率约为11.3%。水提醇沉辅助法用浓度80%乙醇回流1.5 h,然后在80℃下水浴提取1.5 h,测定桑叶中多糖的得率为9.5%。超声辅助提取法提取桑叶多糖的较优方案为超声功率50 W,超声时间10 min,再在料液比1：40（g/ml）、提取温度80℃的条件下水浸提取1.5 h,测定桑叶中多糖的得率为11.6%。[结论]3种方法提取桑叶多糖的得率大小顺序依次为超声辅助法〉热水浸提法〉水提醇沉法,综合考虑成本、工作效率等因素,选择超声辅助提取法效果最好。     

奶浆菌多糖的超声波辅助提取工艺的研究

[目的]研究超声波辅助提取奶浆菌多糖的最优工艺。[方法]以水为提取溶剂,以超声波作为提取辅助设备,通过单因子试验确定影响奶浆菌多糖提取的主要因素及其最佳水平范围,通过L9(34)正交试验确定其最优提取条件。[结果]影响超声波辅助提取奶浆菌多糖的主次因素依次为浸提温度、超声波处理时间、料液比、浸提时间,最优工艺条件是超声波处理时间30 min,料液比1∶25 g/ml,浸提温度80℃,浸提时间为2.5 h。该工艺条件下奶浆菌多糖的提取率为7.16%。[结论]试验得出的最优工艺条件可为奶浆菌多糖的开发利用提供依据。     

响应面法优化茅苍术多糖的提取工艺

[目的]利用响应面分析法优化茅苍术多糖的提取工艺。[方法]根据中心组合设计原理,以提取温度、提取时间、料液比三个因素为自变量,多糖的提取得率为响应值,设计了3因素3水平响应面分析试验,来确定茅苍术多糖提取的最佳工艺条件。[结果]茅苍术多糖提取的最佳工艺条件为：提取温度87℃,料液比1∶22,提取时间3.1 h。在此最佳条件下,茅苍术多糖的提取率为2.12%。[结论]该研究对大规模提取茅苍术多糖有一定理论指导价值。     

茯苓多糖发酵工艺的优化

研究了茯苓多糖发酵过程中碳源、氮源、pH值对多糖积累的影响。结果表明:葡萄糖、玉米粉、蛋白胨均有利于菌丝的生长和多糖的形成,其作用大小为碳源>氮源>pH值。并通过正交优化实验,确定了茯苓多糖的最佳发酵培养基为:葡萄糖4%、玉米粉4%、蛋白胨0.4%、麸皮6%(、NH4)2SO40.2%、MgSO4.7H2O 0.05%、KH2PO40.1%。利用此培养基在10 L发酵罐上进行发酵,茯苓多糖含量最高可达16 g/L。     

白首乌地上部分多糖的微波提取技术研究

[目的]提取白首乌地上部分多糖并测定含量。[方法]采用微波技术,通过正交试验探讨白首乌(Cynanchum auriculatum Aerial Parts)地上部分多糖提取的最佳工艺,用苯酚-硫酸法在波长490 nm处测定吸光度。[结果]结果表明,用苯酚-硫酸法在波长490 nm处测定吸光度,得白首乌地上部分粗多糖含量为2.57%。微波提取白首乌地上部分多糖的最佳工艺参数为料液比1∶25、微波强度80%、提取时间80 s。[结论]该研究为白首乌地上部分资源的开发提供依据。     

直立型川麦冬多糖含量变化规律的初步研究

[目的]初步探讨直立型川麦冬多糖含量的变化规律。[方法]在川麦冬主产区,采用原位动态法采集供试品,硫酸-苯酚比色法测定麦冬多糖含量,相关回归法分析麦冬多糖与生育时间的变化规律。[结果]直立型川麦冬中的多糖含量y(mg/g)与生育年限x(d)的变化规律是:y=147.212 2 lnx-34.388 2(n=7,0≤x≤730,0≤y≤427.06,r0.01=0.95074,r=0.9560)。[结论]在一定生育时间范围内(0≤x≤730 d),直立型川麦冬中的多糖含量y1(mg/g)与生育时间x(d)呈显著的正相关。     

苦瓜多糖脱蛋白方法的比较研究

[目的]寻找合适的苦瓜多糖脱蛋白方法。[方法]比较了Seveage法、酶法、酶-Seveage结合法、三氯乙酸法以及盐酸法对苦瓜粗多糖的脱蛋白效果。[结果]酶-Seveage结合法的脱蛋白效果最佳,木瓜蛋白酶用量为1.25%（V/V）,pH 6.5,温度60℃,时间为2 h,再用Se-veage试剂脱蛋白1次,蛋白质去除率达77.2%,多糖损失率仅为19.3%。[结论]酶与Seveage结合法是一种有效的脱蛋白方法,此法可以较好地脱除游离蛋白,并使多糖损失较少。