寡聚糖激发子对杨树抗溃疡病的诱导作用

【目的】研究寡聚糖激发子对毛白杨愈伤组织抗杨树溃疡病菌的诱导作用。【方法】分别采用筛选出降解杨树溃疡病菌丝体、壳聚糖、果胶糖且活性较高的寡聚糖激发子A1、B、C3诱导毛白杨愈伤组织,以无菌水处理的毛白杨愈伤组织为对照,并在诱导48 h后挑战接种杨树溃疡病菌,测定毛白杨愈伤组织内Vc、可溶性蛋白质和可溶性糖含量的变化。【结果】经A1、B、C3 3种寡聚糖激发子诱导48 h后接种杨树溃疡病菌,毛白杨愈伤组织中Vc、可溶性蛋白质含量的变化基本上呈单峰曲线,A1、B、C3 3种寡聚糖激发子诱导接种的毛白杨愈伤组织中Vc含量峰值比对照峰值分别提高了99.02％,95.46％和85.64％;寡聚糖激发子诱导接种的毛白杨愈伤组织中可溶性蛋白质含量在发病初期（0～48 h）比对照高,在发病后期（60～96 h）均缓慢下降,而对照毛白杨愈伤组织中的可溶性蛋白含量在60 h时上升到最高峰（4.48 mg/g）,均高于3种寡聚糖激发子诱导接种毛白杨愈伤组织,之后急剧下降,至96 h时为2.33 mg/g,比3种寡聚糖激发子诱导接种毛白杨愈伤组织都低;4个处理毛白杨愈伤组织中可溶性糖含量的变化呈双峰曲线,寡聚糖激发子A1、B、C3诱导接种的毛白杨愈伤组织中可溶性糖含量最大值分别比对照的最大值高42.4%,27.6%和16.5%。方差分析表明,A1、B、C3 3种寡聚糖激发子对挑战接种毛白杨愈伤组织中的Vc、可溶性蛋白质和可溶性糖含量均有极显著影响（P<0.01）。【结论】在一定质量浓度范围内,寡聚糖激发子可诱导毛白杨愈伤组织中的Vc、可溶性蛋白质和可溶性糖含量明显提高,从而增强了其抗杨树溃疡病菌入侵的能力。     

安康魔芋软腐病防治技术初步研究

魔芋产业发展迅速,已成为中国西部经济发展中最具成长潜力与竞争优势的地方特色资源产业。在魔芋种植过程中,软腐病发生严重,已成为限制魔芋产业发展的主要因素。传统的化学农药防治效果不理想,急需寻找新的防治途径。为研究出有效的防治魔芋软腐病新技术,应用壳寡糖、海藻酸寡糖植物免疫诱导剂,结合使用噻霉酮制剂,在陕西安康针对魔芋软腐病防治技术进行初步研究。结果表明：药剂拌种处理效果好于浸种处理效果,浸种处理只有噻霉酮对魔芋软腐病有一定的防治效果,防效为51.17%。噻霉酮、壳寡糖及农用链霉素单一药剂对种芋拌种处理,对魔芋软腐病防效分别为68.92%、55.36%和  56.49%,噻霉酮及壳寡糖拌种处理对出苗有明显的促进作用。拌种处理结合在成株期喷施壳寡糖、海藻酸寡糖和噻霉酮,对魔芋软腐病有较好的防治效果,防治效果50%~70%,延迟魔芋魔芋软腐病的爆发高峰期约一周,提高产量效果明显。用噻霉酮杀菌剂拌种处理种芋,在发病初期再用壳寡糖或海藻酸寡糖植物免疫诱导剂结合噻霉酮喷施植株,对魔芋软腐病有较好的防治效果。     

海藻寡糖在农业领域的应用研究进展

海藻寡糖是海藻多糖经过降解得到的一系列寡糖片段,分子量低、水溶性好,具有广泛的生物活性优势,在农业生产中具有广阔的应用前景。文章对近年来海藻寡糖在土壤修复和促进植物生长两方面的研究进展进行综述,同时指出海藻寡糖对土壤重金属的不同作用效果限制了其在土壤修复中的进一步应用、土壤微生物对海藻寡糖—重金属络合物的影响机理不明及海藻寡糖作为植物诱导剂在实际应用中存在局限性等问题。因此,今后在海藻寡糖的利用中应注意以下问题:进行土壤修复时,应针对土壤的酸碱度及重金属污染情况,合理选择海藻寡糖的施用量,确定适宜的修复方式;可将海藻寡糖与其他诱导剂或杀菌剂联合使用以解决其作为诱导剂的局限性;此外,海藻寡糖可作为新型肥料添加剂进行深入开发,以促进其在农业领域的进一步应用。     

The Protect Effects of Chitosan Oligosaccharides on Intestinal Integrity by Regulating Oxidative Status and Inflammation under Oxidative Stress

The aim of this study was to evaluate the effects of the dietary supplementation of chitosan oligosaccharides (COS) on intestinal integrity, oxidative status, and the inflammation response with hydrogen peroxide (H₂O₂) challenge. In total, 30 rats were randomly assigned to three groups with 10 replications: CON group, basal diet; AS group, basal diet + 0.1% H₂O₂ in drinking water; ASC group, basal diet + 200 mg/kg COS + 0.1% H₂O₂ in drinking water. The results indicated that COS upregulated (p < 0.05) villus height (VH) of the small intestine, duodenum, and ileum; mucosal glutathione peroxidase activity; jejunum and ileum mucosal total antioxidant capacity; duodenum and ileum mucosal interleukin (IL)-6 level; jejunum mucosal tumor necrosis factor (TNF)-α level; duodenum and ileum mucosal IL-10 level; the mRNA expression level of zonula occludens (ZO)-1 in the jejunum and ileum, claudin in the duodenum, nuclear factor-erythroid 2-like 2 in the jejunum, and heme oxygenase-1 in the duodenum and ileum; and the protein expression of ZO-1 and claudin in jejunum; however, it downregulated (p < 0.05) serum diamine oxidase activity and D-lactate level; small intestine mucosal malondialdehyde content; duodenum and ileum mucosal IL-6 level; jejunum mucosal TNF-α level; and the mRNA expression of IL-6 in the duodenum and jejunum, and TNF-α in the jejunum and ileum. These results suggested COS could maintain intestinal integrity under oxidative stress by modulating the intestinal oxidative status and release of inflammatory cytokines.     

褐藻酸寡糖对草莓叶片光合及植株形态特性的影响

褐藻酸寡糖对草莓的形态指标和光合特性有显著的促进作用，本试验的目的是筛选出能促进草莓生长、提高果实品质最佳的褐藻酸寡糖。以“红颜”草莓品种为试验材料，采用不同聚合度的褐藻酸寡糖对草莓的形态特征、叶片光合特性指标和品质影响进行研究。结果表明，褐藻酸寡糖能提高草莓叶片SPAD值，能促进叶片的光合特性，提高草莓根系活力。褐藻酸寡糖1号（聚合度为50）处理的净光合速率、根系特征和草莓品质最好。     

Characterization of the FODMAP-profile in cereal-product ingredients

Cereal-based products, such as bread, are staple foods in the western diet. Due to the nature of their basic ingredients and the diversity of recipes, the amount of fermentable short-chain carbohydrates (FODMAPs) in those products may be high. This study characterized the FODMAP-profiles of a broad range of cereal-product ingredients, serving as a basis for low FODMAP product development. Different cereals, pseudo-cereals, gluten-free flours, pulses, pulse protein ingredients, commercial sprouts, and other cereal-product ingredients were analyzed, using anion-exchange chromatography with electrochemical detection. Wheat and related cereals were high in fructans. Pulses, such as peas contained high galactooligosaccharides (GOS) amounts. Whereas GOS levels in pulse protein ingredients varied, depending on their production. Gluten-free flours, for instance, rice-flour, showed low FODMAP-profiles. Amongst those, buckwheat, which does not contain any of the FODMAPs investigated, contained high amounts of other soluble non-digestible carbohydrates, namely fagopyritols; these may have a similar effect on a sensitive gut as GOS. Finally, ingredients contained mainly high levels of fructans and GOS. Yet, the analysis of commonly consumed commercial cereal products, including bread, pasta, crackers and biscuits, highlighted the relevance of lactose, fructose in excess of glucose and polyols. These products serve as benchmarks for further product development.     

国产大豆低聚糖在点心面包中的应用研究

研究国产大豆低聚糖在点心面包中的应用。利用单因素实验设计研究大豆低聚糖的添加量,并测定面包的老化度以及水分活性和细菌总数之间的关系。结果表明,点心面包中的大豆低聚糖经发酵后损失不到10%,在24h内,加入大豆低聚糖的面包组与对照组比较其硬度有显著性差异(P<0.01),48h后几乎无差别(P>0.05),添加1.7%纯大豆低聚糖的点心面包,在贮存1～9d内,水分活性和细菌总数低于空白组,说明添加大豆低聚糖可延长产品的保值期。     

Effects of soybean oligosaccharides on lipid metabolism of Japanese flounder (Paralichthys olivaceus Temminck et Schlegel) fed animal or plant protein source-based diets

A feeding trial was conducted to investigate the effects of dietary soybean oligosaccharides (SBOS) on the levels of cholesterol in plasma and liver, and the fatty acid composition in muscle and liver of juvenile Japanese flounder (Paralichthys olivaceus Temminck et Schlegel). Four isonitrogenous and isocaloric practical diets (crude protein 49%, gross energy 19 kJ/g) including only fish meal (FM) or soy protein isolate (SPI) as sole dietary protein source with (Diets FMO and SPIO) or without (Diets FM and SPI) supplemented SBOS (stachyose, 2.61%; raffinose, 0.61%) were formulated. Each diet was randomly assigned to triplicate aquaria stocked with 30 fish (initial body weight 1.93 ± 0.02 g) each. Fish were maintained in the flow-through aquaria at water temperature ranging from 22.0°C to 25.0°C and fed twice (08:00, 16:00) daily to apparent satiation for 8 weeks. Dietary SBOS supplementation significantly increased the levels of total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) in plasma of the fish fed FM-based diets (P < 0.05), but no significant differences were observed at the levels of plasma triacylglycerol (TG) and low-density lipoprotein cholesterol (LDL-C) and LDL-C/HDL-C ratio (P > 0.05). The levels of TC, TG, HDL-C and LDL-C, and LDL-C/HDL-C ratio in plasma of the fish fed SPI-based diets were not significantly influenced by the supplemented SBOS (P > 0.05). Supplementation of SBOS did not influence the hepatic TC, TG and lipid contents and lipid droplet accumulation in fish fed FM-based diets, but significantly decreased the hepatic TC, TG and lipid contents and lipid droplet accumulation in fish fed SPI-based diets (P < 0.05). In contrast, supplemented SBOS significantly increased fecal cholesterol extraction in the fish fed FM-based diets (P < 0.05), but no significant difference was observed in the fish fed SPI-based diets (P > 0.05). The fatty acid composition in muscle and liver was not significantly affected by supplemental SBOS regardless of dietary protein source (P > 0.05). These results indicate that dietary SBOS supplementation (stachyose, 2.61%; raffinose, 0.61%) does not negatively affect the lipid metabolism of the fish fed FM-based diets, but decrease the incidences of fatty liver of the fish fed SPI-based diets.     

Effects of dietary mannan oligosaccharides in early weaning diets on growth,survival, fatty acid composition and gut morphology of gilthead sea bream (Sparus aurata,L.) larvae

Early weaning of marine fish larvae with dry diets delays gut maturation and reduces growth rates. In juvenile and adult forms of several marine fish species, inclusion of dietary mannan oligosaccharides (MOS) improves gut integrity and functionality, but the effects of MOS inclusion in gilthead sea bream (Sparus aurata, L.) larval diets have not been addressed yet. Thus, this study assesses the effects of dietary MOS inclusion on survival, growth performance, gut morphology, feed acceptance and quality of gilthead sea bream larvae. For that purpose, 16 days post‐hatched gilthead sea bream larvae were fed four graded levels of MOS (Biomos^®, Alltech, Nicholasville, KY, USA) in weaning diets as follows: 0 g kg^?1 MOS, 0.5 g kg^?1 MOS, 1.5 g kg^?1 MOS and 2 g kg^?1MOS. Dietary MOS did not affect feed acceptance in gilthead sea bream larvae (P > 0.05). MOS supplementation was correlated in a dose‐dependent way with higher larval survival (P = 0.026). After 15 days of feeding, dietary MOS increased whole larvae (P < 0.01) arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid. Gilthead sea bream larvae fed 2 g kg^?1 MOS presented higher gut occupation with goblet cells after feeding compared with larvae fed the other dietary treatments. Overall, the results suggest that inclusion of MOS in early weaning diets for gilthead sea bream improves essential fatty acid utilization and may promote growth and final survival.     

饲料添加半乳甘露寡糖对刺参幼参生长、体壁营养组成及免疫力的影响

以初始体质量为(1.79±0.06) g的刺参(Apostichopus japonicus)为研究对象, 进行为期8周养殖实验, 研究饲料中添加半乳甘露寡糖对刺参生长、消化、体壁营养组成及免疫力的影响。以基础饲料(E0)为对照组, 在基础饲料中分别添加0.2% (E1)、0.4% (E2)、0.8% (E3)、1.2% (E4)和1.6% (E5)的半乳甘露寡糖, 共配制5种实验饲料。结果表明: (1) 饲料中添加不同浓度的半乳甘露寡糖对幼参增重率及特定生长率具有显著影响, 各处理组均显著高于对照组(P<0.05), 而对脏壁比及肠壁比无显著影响(P>0.05), 1.2%(E4组)添加水平下, 刺参增重率及特定生长率最高。(2) 饲料中添加不同浓度的半乳甘露寡糖对幼参肠道蛋白酶、淀粉酶、纤维素酶活力均无显著影响(P>0.05)。(3) 饲料中添加不同浓度的半乳甘露寡糖对幼参体壁酸性黏多糖及糖醛酸含量无显著影响(P>0.05)。添加半乳甘露寡糖比例0.2%(E1)、0.4%(E2)、0.8%(E3)、1.2%(E4)的处理组, 刺参体壁氨基酸总量及谷氨酸、甘氨酸、精氨酸含量显著高于对照组(P<0.05), 而1.6%(E5)组体壁氨基酸总量及Glu、Gly、Arg含量与对照组无显著差异(P>0.05)。(4) 饲料中添加半乳甘露寡糖对体壁及体腔液超氧化物歧化酶、碱性磷酸酶及溶菌酶活性具有显著影响(P<0.05), 同时对体腔细胞溶菌酶活性影响显著(P<0.05)。实验可以得到以下结论: (1) 饲料中添加半乳甘露寡糖不仅可以提高刺参免疫力, 并且可以提高特定生长率, 并改善体壁氨基酸组成; (2) 刺参饲料中半乳甘露寡糖的合适添加比例为1.2%。