Effects of β-Glucan Supplementation on Repairing of Phenol-Induced Vaginal Mucosal Epithelium Damage in Rats

Objective: To investigate the effects of different concentrations of β-glucan on the repair of damaged vaginal mucosa, the expression of vascular endothelial growth factor (VEGF), and the inflammatory factor-6 (IL-6) in vaginal tissues. Methods: Thirty-six adult female specific pathogen free (SPF)-grade Wistar rats were randomly divided into 3 phase groups with 12 rats each. Vaginal inflammation rat models were established by injecting phenol gel into the vagina of each rat at a dose of 0.1 ml/100g body weight. After modeling, rats were divided into 4 groups based on different concentrations of the test agent. The control group was injected with 0.5 ml of saline, experimental group A was injected with 0.375 ml saline 0.125 ml β-glucan, experimental group B was injected with 0.25 ml saline 0.25 ml β-glucan, and experimental group C was injected with 0.50 ml β-glucan. The injection sites were selected at the 3 o’clock and 9 o’clock positions of the vagina. Rats were sacrificed at 7-, 14-, and 28-days post-injection, and tissue samples were collected from the injection sites and prepared for histological analysis. New blood vessels and fibroblast numbers in the tissues were observed after Hematoxylin-eosin (HE) staining. The expression levels of VEGF and IL-6 in the tissues were measured using quantificational reverse transcription polymerase chain reaction (qRT-PCR). Results: Histological examination of vaginal tissue specimens at 7-, 14-, and 28-days post-injection showed that on day 7, there were no significant changes in the experimental groups compared to the control group. However, on days 14 and 28, the experimental groups showed more new blood vessels, macrophages, and fibroblasts with increased activity compared to the control group. The expression levels of VEGF in vaginal tissues were elevated on days 14 and 28 in the experimental groups. The comparison of IL-6 levels in vaginal tissues on day 28 showed that serum IL-6 levels returned to normal, and there was no statistically significant difference between the experimental and control groups. Conclusion: In the 3 experimental phases, the increase in VEGF levels in vaginal tissues on day 14 post-injection was more pronounced with higher concentrations of β-glucan, and IL-6 levels returned to normal on day 28. β-Glucan can enhance VEGF levels in damaged vaginal tissues, promote the repair of damaged vaginal tissues, and higher concentrations of β-glucan have a better effect.

(1-3)-β-D葡聚糖联合降钙素原、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究

目的探讨(1-3)-β-D葡聚糖联合降钙素原(procalcitonin,PCT)、CD4^(+)T淋巴细胞多指标在艾滋病患者马尔尼菲篮状菌感染早期诊断临床研究。方法回顾性选取我院2020年1月—2022年6月住院的120例艾滋病患者为研究对象。依据实验室结果,将其分为马尔尼菲篮状菌感染确诊组(血或组织液培育养出马尔尼菲篮状菌),简称A组(62例),及马尔尼菲篮状菌感染临床诊断组[根据临床症状、体征、血常规及(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞多指标诊断],简称B组(58例)。检测患者(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞的表达水平,采用受试者工作特征(receiver-operating characteristic,ROC)曲线下面积(area under the curve,AUC)评估上述指标联合检测对艾滋病患者感染马尔尼菲篮状菌的诊断效能。结果A组的(1-3)-β-D葡聚糖和PCT水平均高于B组,CD4^(+)T淋巴细胞个数低于B组(P<0.05);(1-3)-β-D葡聚糖、PCT、CD4^(+)T淋巴细胞联合检测的AUC为0.933,(1-3)-β-D葡聚糖单独检测的AUC是0.812,PCT单独检测的AUC为0.883,CD4^(+)T淋巴细胞单独检测的AUC是0.810,(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的AUC皆优于三项单独检测,表明(1-3)-β-D葡聚糖、PCT和CD4^(+)T淋巴细胞联合检测的诊断价值皆优于单一指标诊断,且联合检测的特异度、约登指数分别为92.43%和0.580,均高于三项单独检测。结论(1-3)-β-D葡聚糖联合PCT和CD4^(+)T淋巴细胞多指标对艾滋病马尔尼菲篮状菌感染具有非常高的临床诊断价值,能够帮助医生分析出高危风险患者,及时制定治疗方案,同时也承担预后效果的判断依据,对治疗艾滋病马尔尼菲篮状菌感染具有非常重要的研究价值。

Effects of dietary yeast β-glucan on nutrient digestibility and serum profiles in pre-ruminant Holstein calves

This study aimed to investigate the effects of dietary supplementation of yeast 13-glucan on the nutrient digestibility and serum profiles in pre-ruminant Holstein calves. Forty-two neonatal Holstein calves （（39.6＋4.2） kg） were randomly allotted to six groups, and each was offered one of the following diets： a basal diet （control） or the basal diet supplemented with 25, 50, 75, 100 or 200 mg of yeast 13-glucan kg-~ feed （dry matter basis）. The basal diet consisted of a milk replacer and a starter feed. The trial lasted for 56 d. Two digestibility trials were conducted from d 14 to 20 and from d 42 to 48. Blood samples were collected on d 0, 14, 28 and 42 for serum profile analyses. On d 56, three calves from each group were slaughtered, and intestinal samples were collected to assess the villous height, crypt depth and mucosal thickness. Although feed intake was not affected by dietary treatment （P〉0.05）, the average daily gain （ADG） and gain-to-feed ratios were higher （P〈0.05） for the calves fed 75 mg of yeast β-glucan kg^-1 feed than those in the other groups. The supplementation of yeast β-glucan at 75 mg kg^-1 feed increased the apparent digestibility of dry matter （DM）, crude protein （CP）, ether extract （EE）, and phosphorus （P） （P〈0.05） and the ratio of intestinal villous height to crypt depth （V/C） （P〈0.05） when compared with the control group. No effects of yeast β-glucan on the serum concentrations of total protein （TP）, albumin （ALB）, serum urea nitrogen （SUN） and glucose （GLU） were observed （P〉0.05）. Compared with the control group, supplementation of yeast β-glucan decreased （P〈0.05） the serum concentrations of triglycerides （TG） and total cholesterol （TC）. The serum concentration of immunoglobulin G （IgG） and immunoglobulin M （IgM） increased quadratically （P〈0.05）, whereas the serum concentration of immunoglobulin A （IgA） was unaffected by dietary treatments （P〉0.05）. The supplementation of yeast β-glucan stimu- lated the enzymatic activity of alkaline phosphatase （ALP） （P〈0.05） compared with the control group. The lysozyme （LYZ） concentration increased quadratically （P〈0.05） with increasing yeast β-glucan levels. The results suggested that dietary supplementation of yeast 13-glucan at 75 mg kg^-1 feed improved nutrient digestibility, enhanced immunity by increasing the immunoglobulin concentration and stimulating ALP, and exerted no adverse effects on metabolism in pre-ruminant calves.

冷冻球磨处理时间对糯米淀粉-β-葡聚糖复合物理化性质和消化性的影响

以糯米淀粉(WRS)和燕麦-β-葡聚糖为原料(OBG),探究不同冷冻球磨处理时间制备的糯米淀粉-β-葡聚糖复合物的理化性质和消化性的影响,采用扫描电子显微镜、红外光谱仪、流变仪等仪器和模拟体外消化的方法,对所制备不同处理时间的复合物的理化性质和消化性进行表征和评价。结果表明,随着冷冻球磨时间的延长,其复合物颗粒表面变得粗糙,颗粒形状不规则,出现团聚、结块的现象。红外光谱结果表明:各吸收峰没有明显的变化,未形成新的化学键,冷冻球磨处理使OBG通过氢键作用镶嵌或附着与糯米淀粉结合。复合物的相对结晶度从29.72%降至8.62%,短程有序性也逐渐下降。同时,复合物的双螺旋结构含量降低,无定形区含量显著增加。随着冷冻球磨时间的延长,其峰值黏度和回生值分别从931.00,103.33 cP降至159.33,41.00 cP,稠度系数K、G′和G″值均下降,增强了体系的流动性和稳定性。在消化性方面,冷冻球磨制备的复合物比原糯米淀粉消化率低。当球磨时间为60 min,其复合物的抗性淀粉含量最高,为35.92%。本研究为淀粉加工和改性提供新的研究方法和技术手段。

PREPARATION AND STRUCTURE OF FIVE DERIVATIVES OF β-(1→3)-D-GLUCAN ISOLATED FROM PORIA COCOS SCLEROTIUM

A new solvent of cellulose (1.5 mol/L NaOH/0.5 mol/L urea aqueous solution) was used as one of the homogeneous reaction media of polysaccharides for methylation, hydroxyethylation and hydroxypropylation. A water insoluble β -(1—>3)-D-glucan, sample PCS3- isolated from fresh sclerotium of Poria cocos was sulfated in dimethyl sulfoxide (Me 2 SO), carboxymethylated in NaOH, isopropanol solution, as well as methylated, hydroxyethylated and hydroxypropylated in the new solvent system, respectively, to obtain five water-soluble derivatives coded as S-PCS3- C- PCS3- M-PCS3- HE-PCS3- and HP-PCS3- Their chemical structure and distribution of substitution were characterized by infrared spectroscopy (IR), elementary analysis (EA), 1 H-NMR, 13 C-NMR, 2D-COSY, 2D-TOCSY and 2D- 1 H-detected 1H 13C HMQC spectra. The results reveal that the relative reactivity of hydroxyl groups of the β -(1-?3)-D-glucan is in the order C-6 > C-4 > C-2 on the whole. The substitution of the samples S-PCS3- C-PCS3- and M-PCS3- occurred mainly at C-6 position and secondly at C-4 and C-2 positions, and that of HE-PCS3- occurred at C-6 and C-4 positions and of HP-PCS3- almost completely occurred at C-6 position. The degrees of substitution (DS) obtained from 13 C-NMR range from 0.23 to 1.27. The water solubility of the derivatives is in the order S-PCS3- >C-PCS3- >M-PCS3- >HE-PCS3- >HP-PCS3- This work provides a novel and nonpolluting process for the methylation, hydroxyethylation and hydroxypropylation of β -(1—>3)-D-glucan.

STRUCTURE,MOLECULAR WEIGHT AND BIOACTIVITIES OF(1→3)-β-D-GLUCANS AND ITS SULFATED DERIVATIVES FROM FOUR KINDS OF LENTINUS EDODES

Lentinan samples,(1→3)-β-D-glucans containing 4.6-15.2 wt% proteins,coded as L-I_1 L-I_2 L-I_3 and L-I_4(L-I)were isolated from four kinds of Lentinus edodes.These glucans were treated with acetone to remove the protein in orderto obtain free protein glucans coded as LNP-I_1,LNP-I_2.LNP-I_3 and LNP-I_4(LNP-I).The free-protein polysaccharideswere sulfated to give derivatives(S-LNP-I)with degree of substitution(DS)from 0.4-0.8.The structural features andweight-average molecular weight(M_w)of the samples were investigated by using infrared spectroscopy,elemental analysis,^(13)C-NMR,size exclusion chromatography combined with laser light scattering(SEC-LLS)and viscometry.The effects ofstructure and conformation of the polysaccharides on antitumor activities were assayed in vivo(Sarcoma 180 solid tumors)and in vitro(Sarcoma 180,HL-60,MCF-7 and Vero tumors).The results indicated that the predominant species of thesamples L-I and LNP-I in 0.2 mol/L NaCl aqueous solution existed as triple-helical chains with high rigidity and in dimethylsulfoxide(DMSO)as single-flexible chains.Interestingly,the antitumor activities of LNP-I are lower than those of the nativeglucans(L-I),whereas their sulfated derivatives have higher inhibition ratio against Sarcoma 180 than LNP-I.The resultsreveal that the binding of protein,sulfated modification and the triple helix conformation are important factors in theenhancement of the antitumor activities of polysaccharides on the whole.

Yeast-Derived β-1,3-Glucan Substrate Significantly Increased the Diversity of Methanogens During In vitro Fermentation of Porcine Colonic Digesta

The β-1,3-glucan from yeast has been extensively examined for its immuno-enhancing effects in animals.However,investigation on the relationship among β-glucan,gut microbiota and immune-modulating effects remains limited particularly in pigs.Considering the critical roles of gut methanogens in the microbial fermentation,energy metabolism and disease resistance,we investigated the phylogenetic diversity of methanogens from fermented cultures of porcine colonic digesta with（G） or without（N） yeast β-glucan based on sequences of the archaeal 16S rRNA gene.A total of 145 sequences in the G library were assigned into 8 operational taxonomic units（OTUs） with the majority of sequences（114/145） related to strains Methanobrevibacter millerae or Methanobrevibacter gottschalkii with high identities ranging from 97.9 to 98.6%,followed by 23 sequences to Methanobrevibacter ruminantium,2 sequences to Methanobrevibacter smithii and one sequence to Methanobrevibacter wolinii.The 142 sequences in the N library were assigned to 2 OTUs with most sequences（127/142） related to strains M.millerae or M.gottschalkii with sequence identities ranging from 97.9 to 98.5%,and 15 sequences related to M.gottschalkii with 97.9% identity.Shannon diversity index showed that the G library exhibited significantly higher archaeal diversity（P0.05） and Libshuff analysis indicated the differences in the community structure between the two libraries were significant（P0.0001）.In conclusion,the current study provides evidence that addition of yeast β-glucan significantly increased the diversity of methanogens in in vitro fermented porcine colonic digesta.

Noble strain of Sparassis latifolia produces high content of β-glucan

Objective: To classify four new Sparassis strains(CLM1, CKM1, CKM2, and KJM1) using the internal transcribed spacer sequence and to elucidate their β-glucan content and mycelial growth.Methods: Two different microbiological media were used to determine growth rate. The β-glucan contents were analyzed using the Megazyme Mushroom and Yeast Beta-Glucan kit. To determine the genetic relationships, phylogenetic trees were constructed using ClustalX. Multiple sequence alignments were printed and shaded with the BOXSHADE 3.21 program. Results: In this study, four new Sparassis strains were isolated from the southern region of the Korea Peninsula. They were all classified into the Sparassis latifolia clade as a monophyletic group based on the internal transcribed spacer sequence. Mycelial growth rate of the CLM1 strain was highest in potato dextrose agar and potato dextrose agar larch. The β-glucan content of the CLM1 strain was highest at 29.5%(w/w). A high degree of sequence divergence was detected in the RNA polymerase second largest subunit II gene(RPB2) within Sparassis spp. tested. The putative amino acid sequences of the RPB2 had a distinct sequence. The nucleotide sequences of the RPB2's intron were also divergent among Sparassis spp., even though their nucleotide length was well conserved within Sparassis latifolia. Conclusions: These results indicate that the nucleotide sequences and the amino acid sequences of RPB2 can be used to identify individual Sparassis sp. The Sparassis strain CLM1 may be best for developing a remedy to prevent or treat cancer and other chronic diseases.

Cultivar and Environmental Effects on p-glucanase Activity in Both Barley Grain and Malt and Its Function in β-glucan Degradation

Eight two-rowed barley cultivars were grown at seven locations in the southern winter-barley zone of China. Mean grainβ-glucanase activity ranged from 39.89 U kg-1 for Suyin2 to 49.75 U kg-1 for Xi-umai3 in 8 cultivars grown at 7 locations, and from 38. 74 U kg-1 in Zhengzhou to 57. 96 U kg-1 in Putian among 7 locations on an average of all cultivars. Correspondingly, mean malt β-glucanase activity of 8 cultivars ranged from 313.33 U kg-1 for ZAU3 to 489. 89 U kg-1 for Daner Barley, and of 7 locations from 330.40 U kg-1 in Yancheng to 418. 24 U kg-1 in Putian. There were significant differences among cultivars and locations in maltβ-glucanase activities. The locations showed much larger variation in maltβ-glucanase activities than cultivars. The reduction of total β-glucan content after malting varied in both cultivars and locations, with a mean of 78.31%. The analysis of correlations showed that maltβ-glucan content was significantly positively and negatively correlated with grain β-glucan content and malt β-glucanase activity, respectively, and malt β-glucanase activity was significantly positively correlated with grain β-glucanase activity.

β-葡聚糖的生物学功能及其在动物生产中的应用

葡聚糖是一种天然多糖,可作为绿色添加剂应用于食品和养殖等多个领域,具有可持续性和生态友好性。β-葡聚糖具有多种生物学功能,可抑制和清除体内过量的自由基,激活机体抗氧化酶系统,降低氧化应激的程度;β-葡聚糖可通过调控炎症通路降低炎性因子的产生,缓解炎症引起的组织损伤;β-葡聚糖可修复肠道屏障及调节肠道微生态,减少细菌和毒素的渗透;β-葡聚糖可调节糖脂代谢,确保动物获得足够的能量供应,从而维持机体健康。文章主要围绕β-葡聚糖的特性、生物学功能及其在畜禽和水产养殖中的应用现状进行综述,以期为β-葡聚糖在动物养殖领域中的进一步应用提供参考。

The Variation of β-glucan and Protein Content in Barley as Affected by Agronomic Practices

The influences of N application rate, timing, sowing date and seeding rate on β-glucan and protein content in barley grains were studied through the field experiments in Hangzhou, China during 1997 -2001. Protein content increased with N application rate and with N proportion applied at late stage. β-glucan content also responded significantly to N application rate and timing, but with different pattern with protein content. Of three N rate treatments, the medium N rate (135 kg ha-1) had the highest β-glucan content, being significantly higher than low N rate (90 kg ha-1) and no difference with high N rate (180 kg ha-1). A-mong three N timing treatments, two times of N top-dressing at both tillering and booting stage had significantly higher β-glucan content than once N top-dressing at tillering or booting stage. Sowing date has the dramatic effect on both β-glucan and protein content. Protein content decreased with the delayed sowing, and kernel weight showed opposite tendency. Either earlier or later sowing caused increased β-glucan content relative to sowing in early November, which is the normal date for barley sowing locally. Seeding rate had no significant influence on both β-glucan and protein content.

β-glucan诱导训练免疫及其在逆转免疫耐受中的应用

目的本研究拟通过在体内和体外诱导训练免疫反应,以探讨诱导训练免疫是否可能逆转免疫耐受状态。方法以β-glucan作为训练免疫诱导剂,建立体外小鼠胫骨来源的巨噬细胞(bone marrow derived-macrophages,BMDM)训练免疫模型:40μg/mLβ-glucan刺激BMDM 24 h,随后用PBS洗涤后让BMDM在完全培养基中静息6 d,在第3天的时候补充培养基,第7天收集细胞100 ng/mL LPS再刺激,4 h后收集细胞抽提RNA和24 h后收集细胞上清;建立β-glucan体内训练免疫模型:野生型C57BL/6J腹腔注射1 mgβ-glucan,对照组腹腔注射200μL的PBS,7 d后感染金黄色葡萄球菌(每只1×10^(4)/200μL PBS)。LPS诱导体外免疫耐受,体外免疫耐受逆转通过在耐受的BMDM中加入40μg/mLβ-glucan刺激24 h,随后让细胞静息1 d,通过促炎因子的恢复水平来反映耐受逆转情况。盲肠结扎穿刺(cecal ligation and puncture,CLP)诱导体内免疫耐受,体内免疫耐受逆转通过向CLP组腹腔注射1 mgβ-glucan,通过再次感染非致死剂量的细菌或真菌的生存率反映耐受逆转情况。结果(1)经过β-glucan训练的BMDM,在LPS再次刺激时产生更高水平的促炎因子TNF-α、IL-6和NO。同时,β-glucan训练的BMDM通过激活m-TOR信号通路,导致细胞代谢模式向糖酵解转变,引起细胞内乳酸增多;(2)β-glucan诱导的体内训练免疫具有保护作用;(3)β-glucan在体外能够逆转LPS诱导的免疫耐受,恢复BMDM促炎细胞因子的产生;(4)目前我们的结果尚未证实β-glucan在体内可以逆转CLP诱导的免疫耐受。结论本研究成功地建立了β-glucan体外和体内训练免疫模型,并证明了在体外β-glucan能逆转LPS诱导的免疫耐受,但是目前结果尚未证实β-glucan在体内能够逆转CLP诱导的免疫耐受,提高二次感染生存率。

大麦籽粒β-葡聚糖含量的全基因组关联分析及候选基因预测

利用高通量SNP芯片对238份不同来源的大麦种质资源进行基因型分析,并测定2年的籽粒β-葡聚糖含量,通过基于PCA模型的一般线性模型(general linear model,GLM)进行全基因组关联分析(genome-wide association study,GWAS)。结果表明,238份大麦材料的β-葡聚糖含量分布在1.23%~6.55%和1.79%~6.64%之间且均呈正态分布。GWAS分析共检测到19个显著的SNP标记,分布在1H、2H、3H、4H和5H染色体上,可解释表型变异的7.39%~10.29%。在显著关联的SNP位点上下游各300 kb范围内进行候选基因挖掘,共寻找到37个基因,基于前人研究和BLAST基因注释共筛选到4个最有可能与β-葡聚糖合成相关的候选基因,在最显著SNP位点B1_1033963上游89 kb处找到候选基因HORVU.MOREX.r3.1HG0000140,该基因可能是与β-葡聚糖合成过程紧密相关的基因。本研究可为大麦β-葡聚糖含量遗传改良提供理论指导与优异基因资源。

燕麦SNP高密度遗传图谱构建及β-葡聚糖含量QTL定位

β-葡聚糖是燕麦发挥保健作用的主要功能因子,提高其含量对优质燕麦生产有着重要意义。为促进高β-葡聚糖燕麦种质资源的有效利用和相关基因发掘,本研究以高β-葡聚糖品种夏莜麦和低β-葡聚糖品种赤38组配衍生的219个家系RIL8群体为材料,利用重测序技术构建了包含21个连锁群,5032个bin标记的遗传连锁图谱,图谱总长2045.09 cM,平均图距0.42 cM。利用标准酶法和近红外法对4个环境的RIL群体家系β-葡聚糖含量进行测定,结合测定结果,利用完备区间作图法对β-葡聚糖含量进行QTL定位分析,结果显示不同环境条件下RIL群体β-葡聚糖含量呈正态分布,并出现超亲后代家系,4个环境下群体β-葡聚糖含量变异系数介于9.06%~16.63%之间。QTL定位检测到7个与燕麦β-葡聚糖含量相关的QTL,分布于2D、3D、4C和4D染色体上,其中贡献率最高为14.73%,在2个环境中检测到同一个QTL,其标记区间为Chr4C_mark8361257–Chr4C_mark8384831。研究结果将为燕麦β-葡聚糖分子标记辅助育种提供重要的理论依据。

纳米酵母β-葡聚糖制备及理化性质分析

酵母β-葡聚糖是一种多功能多糖,不溶于水,呈颗粒状,为拓宽其应用性,本文采用球磨破碎法制备纳米酵母β-葡聚糖,并研究其理化性质。以平均粒径为指标,研究了脱蛋白、冻融等处理对酵母β-葡聚糖球磨破碎的影响,并对球磨工艺进行优化。结果表明,较长时间的高温抽提、脱蛋白、反复冻融和二氧化氯处理均有利于酵母β-葡聚糖的破碎,使得球磨后酵母β-葡聚糖粒径显著(P<0.05)减小。酵母β-葡聚糖最佳球磨工艺条件为:转速850 r/min、球料比10:1、球磨时间120 min。在上述适宜条件下,纳米酵母β-葡聚糖冻干粉的平均粒径为81.16±0.35 nm,其葡聚糖纯度为89.52%。红外光谱分析表明,纳米β-酵母葡聚糖仍保持原有的基本化学结构。纳米酵母β-葡聚糖在水溶液中具有良好悬浮稳定性。与普通酵母β-葡聚糖相比,纳米酵母β-葡聚糖的持油力增大,而持水力和黏度降低。采用球磨破碎法成功制备出纳米酵母β-葡聚糖,其理化性质发生明显变化。本研究可为深度开发酵母β-葡聚糖奠定基础。

刚果红法检测β-1,3-葡聚糖和β-1,3-1,6-葡聚糖条件优化

为了快速高效的检测微生物所产β-1,3-葡聚糖和β-1,3-1,6-葡聚糖含量,通过单因素试验及响应面试验优化刚果红法反应条件,并进行方法学考察。结果表明,最佳反应条件为刚果红质量浓度0.2 g/L,反应温度20℃,反应时间35 min,反应pH 7。在此优化反应条件下,β-1,3-葡聚糖、β-1,3-1,6-葡聚糖吸光度值分别为0.645和0.734。两种葡聚糖的检出限和定量限分别为0.1 g/L、2.0 g/L及0.1 g/L、0.8 g/L。两种β-葡聚糖的精密度试验结果相对标准偏差(RSD)分别为1.09%和1.15%,平均加标回收率为99.6%和100.74%,加标回收率试验结果的RSD分别为2.27%和2.94%。结果显示,刚果红法精密度、准确度良好,适用于微生物产两种β-葡聚糖的定量分析。

青稞酒糟中β-葡聚糖提取工艺优化及理化特性分析

目的 探究青稞酒糟中β-葡聚糖提取工艺及其理化特性。方法 通过单因素和响应面实验优化确定β-葡聚糖提取工艺。利用傅里叶红外光谱(Fourier transform infrared spectroscopy, FT-IR)和高效排阻色谱-示差折光检测器-多角度激光光散射仪(high performance size exclusion chromatography-differential refraction detector-multi-angle laser light scatter, HPSEC-RID-MALLS)联用测定提取物中β-葡聚糖的结构和分子量,并对其加工特性及流变特性进行分析。结果 青稞酒糟中β-葡聚糖最优提取条件为:料液比为1:11 (m:V)、pH 8.5、提取温度80℃、搅拌速度600 r/min、提取时间3.0 h,此条件下提取率为16.29%。FT-IR检测结果表明,提取样品中具有β-葡聚糖特征吸收峰。多糖重均分子量为7.84×10^(4)Da,在100~140℃高温条件和中性偏碱性条件下稳定,在碱性条件及低盐离子浓度条件下促进溶解。流变特性结果表明, β-葡聚糖水溶液表现出非牛顿流体的剪切稀化特性,其表观黏度存在浓度依赖性,具有固体弹性特性。结论 从青稞酒糟中提取的β-葡聚糖具有较好的加工特性及流变性,为青稞酒糟的综合加工及增值化利用提供思路。

蛹虫草β-葡聚糖提取工艺优化及抗氧化活性

以β-葡聚糖得率得率为主要评价指标,通过单因素和响应面试验优化蛹虫草β-葡聚糖超声辅助水提工艺,采用红外扫描分析提取物的化学键及官能团信息,测定其中各组分含量及其体外抗氧化活性。结果表明,蛹虫草β-葡聚糖最优提取工艺为超声时间1 h、料液比1∶31(g/mL)、水浴温度90℃。最优条件下提取得率为(1.94±0.28)%,与预测值1.95%一致。经过纯化试验得出α-葡聚糖去除最优条件为α-淀粉酶添加量2%、孵育时间60 min、温度50℃,经过纯化处理后β-葡聚糖纯度由19.82%提高至33.93%;红外扫描结果表明,蛹虫草β-葡聚糖具有典型的多糖结构,并含有硫酸根基团。蛹虫草β-葡聚糖对DPPH自由基、ABTS+自由基和羟基自由基的清除能力与浓度呈正相关(2.00~10.00 mg/mL),IC_(50)值分别为1.17、2.17、4.35 mg/mL,清除率在浓度为8.34、9.88、9.97 mg/mL时,可达100%。综上,优化后的蛹虫草β-葡聚糖超声辅助水提工艺稳定可行,提取获得的β-葡聚糖具有较好的抗氧化活性。

二甲基亚砜辅助分离酵母细胞壁中β-葡聚糖的工艺探索

酵母β-葡聚糖(yeastβ-glucan)是一种难溶于水、酸、碱等常用溶剂的多糖,因传统的制备工艺复杂、烦琐且产品产量低或纯度不高,导致其产业化困难。作者用碱法结合二甲基亚砜(DMSO)辅助分离对酵母β-葡聚糖的生产制备工艺进行了探索和优化。结果显示:在0.7 g/dL NaOH中80℃处理2.6 h进行碱法除杂,除杂率最大为71.84%;在料液比为30 mg∶1 mL、体积分数80%的DMSO、80℃下分离纯化β-葡聚糖30 min,得到的β-葡聚糖产品纯度达到95.84%。通过薄层色谱和傅里叶红外光谱对产品进行鉴定,表明此产品是由葡萄糖单体聚合而成,呈β构型;抗炎试验表明,此产品具有一定的生物活性。该研究旨在简化生产工艺、扩大生产规模、提高产品质量,以期为工业化生产提供依据。

亚临界水辅助酶联合提取燕麦麸皮β-葡聚糖工艺优化

目的采用亚临界水辅助酶联合提取法提取燕麦麸皮中β-葡聚糖,并对副产物进行测定。方法在单因素实验的基础上,以燕麦麸皮β-葡聚糖得率为指标,通过响应面实验优化亚临界水辅助酶联合提取工艺条件。结果在亚临界水萃取温度为115℃、pH为7.0、酶反应温度为60℃、酶反应时间为30 min、料液比为1:14(g/mL)的条件下,燕麦麸皮中β-葡聚糖的得率最高,达4.385%。酶法提取提升了燕麦麸皮中β-葡聚糖的得率,而亚临界水辅助提取不仅提高得率还大幅缩短了提取时间,最终,燕麦麸皮的综合利用率达到72.78%。结论亚临界水辅助酶联合提取法不仅能够高效高质量提取燕麦麸皮β-葡聚糖,同时有效降低生产成本,提高燕麦资源的利用率。这种方法满足了市场和工业需求,并为相关领域的理论研究提供了重要参考。