香菇果蔬酱软罐头的研究

以香菇、桔皮、南瓜为主要原料,通过正交试验科学优选配方,采用真空浓缩新技术,研制了香菇果蔬酱软罐头。     

香菇多糖和金针菇多糖的提取及其抑菌活性

为了探索食用菌多糖在抗菌方面的开发和应用,采用菌丝体发酵法,制得金针菇和香菇胞外多糖,采用热水浸提结合微波预处理法,提取香菇菌柄多糖,并采用正交试验方法对提取工艺进行优化,然后采用滤纸片法测试金针菇胞外多糖、香菇胞外多糖和香菇菌柄多糖对大肠杆菌、金黄色葡萄球菌和白色念球菌的抑制活性．结果表明：香菇菌柄多糖提取的最佳工艺为微波预处理3mm（处理过程中微波炉的功率为480w）、料液比为1：30（g：mL）、浸提时间为1．5h和浸提温度为96℃．在8．5mg／mL的浓度下,金针菇胞外多糖,对大肠杆菌、金黄色葡萄球菌和白色念球菌均无抑制作用;在4．8mg／mL的浓度下,香菇胞外多糖和香菇菌柄多糖对大肠杆菌、金黄色葡萄球菌和白色念球菌均有抑制活性．香菇胞外多糖,对大肠杆菌、金黄色葡萄球菌和白色念球菌的最小抑菌浓度分别为0．15、4．8、4．8mg／mL;香菇菌柄多糖,对大肠杆菌、金黄色葡萄球菌和白色念球菌的最小抑菌浓度分别为2．4、4．8、4．8mg／mL．不同浓度的香菇多糖对大肠杆菌、金黄色葡萄球菌和白球念球菌的抑制活性不同;香菇胞外多糖和香菇菌柄多糖对大肠杆菌、金黄色葡萄球菌和白球念球菌的抑制活性存在差异．     

Effect of ultraviolet‐B irradiation on antioxidative properties of aqueous extracts from shiitake (Lentinus edodes) mushrooms

Antioxidant properties of aqueous extracts from Lentinus edodes treated with UV‐B irradiation were examined in vitro systems including DPPH, ABTS and oxygen radical absorbance capacity (ORAC) assays and in riboflavin‐photosensitised oil‐in‐water (O/W) emulsions. Changes in total phenolics, total flavonoids and vitamin C were also analysed. Lentinus edodes receiving 25 kJ m^?2 UV‐B treatment showed high radical scavenging ability based on DPPH and ABTS assays compared with samples with 0, 50 and 75 kJ m^?2, while those with 50 kJ m^?2 had higher antioxidant capacities than other samples from ORAC assays. Samples with 25 kJ m^?2 UV treatment had significantly 7.1% higher total phenolic content, 12.0% higher total flavonoid content and 8.0% higher vitamin C content than UV‐B‐untreated sample (P < 0.05), respectively. In O/W emulsions under riboflavin photosensitisation, 25 and 50 kJ m^?2 UV treatment significantly increased the oxidative stability compared with other samples based on headspace oxygen content and lipid hydroperoxide analyses (P < 0.05). Aqueous extracts of UV‐B‐treated mushrooms possessed enhanced antioxidant properties compared with untreated mushrooms.     

Polysaccharides in Lentinus edodes: Isolation,Structure, Immunomodulating Activity and Future Prospective

Lentinus edodes has been valued as edible and medical resources. Polysaccharides have been known to be the most potent antitumor and immunomodulating substance in Lentinus edodes. In this review, we summarize the current knowledge of the polysaccharides isolated from Lentinus edodes, including extraction and purification methods, chemical structure and chain conformation, the effects on innate and adaptive immunity and their mechanism, relationship between structure and function, and the future prospects.     

Analysis of volatile compounds in L. edodes blanched by hot water and microwave

The comprehensive flavour characterisation and volatile compounds of raw L. edodes, hot water blanching (HB) sample and microwave blanching (MB) sample were comparatively analysed by electronic nose technology and headspace solid‐phase micro‐extraction combined with gas chromatography‐mass spectrometry (HS‐SPME‐GC‐MS). Results indicated that volatile components in L. edodes markedly changed after HB and MB. Volatile compounds of raw L. edodes consisted mainly ketones, sulphide and alcohols, and 3‐octanone, as well as 1‐octen‐3‐one, were the major compounds. The content of ketones and sulphides in blanched samples markedly decreased, while the relative content of aldehydes, hydrocarbons and esters increased, which became the major volatile compounds of treatment samples. In addition, the percentage contents of esters, alcohols and sulphides in MB samples were significantly (P < 0.05) higher than that in HB samples, especially 1‐octen‐3‐ol, which contributes more to mushroom flavour. Therefore, MB is a better pretreatment method of L. edodes processing and cooking according to the results of experiment.     

蒽酮-硫酸法测定菌类保健品中的活性多糖

用蒽酮 硫酸法测定灵芝孢子精、灵芝冲剂和香菇等菌类保健品中活性葡聚糖的含量.研究了沸水浴时间、乙醇浓度、硫酸体积等对葡聚糖含量测定的影响,得到较为优化的测定条件.结果表明,该方法的回收率为93.2%～98.4%,相对标准偏差为1.04%～8.12%(n=5).     

微波协同高压热水浸提法提取香菇多糖的研究

研究了香菇多糖的几种提取方法,结果表明,采用微波协同高压热水浸提法可明显提高多糖的得率;探讨了采用此法从香菇中提取活性多糖的最佳条件。通过单因素试验,分析了料液比、微波功率和微波辐射时间对香菇多糖提取率的影响,并以香菇多糖提取率为评价指标,优化提取工艺。试验结果表明,微波协同高压热水浸提法提取香菇多糖的最佳条件为:料液比为1∶50(g/mL)、微波功率为800 W、微波辐射时间为8min。在此条件下,香菇多糖的提取率为13.6%。     

香菇多糖L-2对荷瘤小鼠TNF-α和IL-2的影响

我们提取纯化得到一种重均分子量为2.03×105、单糖为葡萄糖的香菇多糖级分(L-2)后,评价了香菇多糖L-2对荷S-180小鼠细胞免疫的影响。连续10d通过腹腔注射给予小鼠不同剂量的香菇多糖L-2(10mg/kg体重),测定了正常小鼠与荷S-180小鼠的血清中肿瘤坏死因子(TNF-α)和白介素2(IL-2)的含量,以及香菇多糖L-2对TNF-α和IL-2的mRNA表达的影响。与对照组小鼠相比,血清中TNF-α含量有显著增加,而血清中IL-2含量没有变化,与此同时,香菇多糖L-2可以上调TNF-α的mRNA的表达。结果揭示多糖L-2有增加TNF-α含量的作用,多糖增强免疫力与TNF-α含量增加以及在转录水平上调TNF-αmRNA的表达有关。