Selenium-enriched and ordinary green tea extracts prevent high blood pressure and alter gut microbiota composition of hypertensive rats caused by high-salt diet

High-salt diet is well recognized as a risk factor for hypertension,and dietary intervention plays a critical role in the prevention of hypertension.The current study investigated the effects of selenium-enriched green tea(Se-GT)and ordinary green tea(GT)on prevention of hypertension of rats induced by high-salt diet,as well as their potential regulatory and mechanism.Our results showed that GT and Se-GT supplementations significantly prevented the increase of blood pressure(BP),activated the phosphoinosmde-3-kinase/protein kinase B(PI3K/Akt)signaling pathway,and regulated the gene expression related to BP,as well as improved the tissue damage like heart,liver,and kidneys.Besides,the key parameters associated with oxidative stress,inflammation and endothelial dysfunction were also altered by GT and Se-GT treatments.Importantly,GT or Se-GT administration adjusted the diversity and composition of the intestinal flora.Moreover,GT and Se-GT supplementations increased the abundance of beneficial bacteria and reduced the abundance of harmful or conditional pathogenic bacteria.More specifically,GT intake specifically and significantly enriched the relative abundance of Paraprevotella and Bacteroides,whereas Se-GT was characterized by specific and significant enrichment for Allobaculum and Bifidobacterium.Our results proved that dietary supplement of GT and Se-GT remarkably improved the vascular functions and effectively prevented tissue damage by regulation of intestinal flora,and thus preventing hypertension induced by high-salt diet.

Research on Strategies for the Development of Selenium-enriched Tea in Ankang City of Shaanxi Province in the Context of Targeted Poverty Alleviation

As an important symbol of agricultural and sideline products in Ankang City,selenium-enriched tea affects the development of regional agricultural and sideline industries.In this paper,the development status and problems of the selenium-enriched tea products of Ankang were analyzed in terms of capital,technology,management and sales mode.This research is of positive significance to the development of selenium-enriched products and other agricultural and sideline products of health value,and plays a very important role in promoting the cultivation of village-level characteristic industries and the effective realization of targeted poverty alleviation.

Study on Extraction Method of Selenium-enriched Rice

[Objectives] The aims were to optimize the extraction process of selenoproteins from selenium-enriched rice in Guangxi and provide references for the intensive processing and comprehensive utilization of selenium protein resources. [Methods]Selenium-enriched rice was used as materials to extract selenoproteins by phosphate buffer extraction method and to optimize the extraction process of selenoproteins by using the orthogonal experiment. Proteins and selenium content was measured by Coomassie Brilliant Blue G-250 reagent and AFS（ atomic fluorescence spectrometry） respectively. [Results] The most significant factor affecting extraction of rice Selenoproteins was extraction NaO H concentration,followed by the ratio of solid-liquid,temperature and then extraction time. The optimum extraction conditions of selenoproteins from rice were extraction temperature of 50 ℃,NaO H concentration of 0. 14 mol/L,extraction time of 5 h,and solid-liquid ratio of 1∶ 30. [Conclusions]The alkali extraction process optimized by orthogonal test could effectively improve the extraction rate of selenoproteins,and the optimized process parameters could be popularized and applied in practical production.

Analysis of Influencing Factors in Production of Selenium-enriched Eggs

Selenium is an essential trace element for human health.Eating selenium-enriched eggs is conducive to easily and effectively solving the problem of selenium deficiency.In the production process of selenium-enriched eggs,different selenium sources,additive doses,feeding time,and the addition of other vitamins,trace elements,and methionine in the diet will influence the deposition of selenium in eggs.Through this review,it is intended to provide a reference for the practical,safe and economical production of selenium-enriched eggs.

Incorporation ofκ-carrageenan improves the practical features of agar/konjac glucomannan/κ-carrageenan ternary system

Three materials(agar,konjac glucomannan(KGM)andκ-carrageenan)were used to prepare ternary systems,i.e.,sol-gels and their dried composites conditioned at varied relative humidity(RH)(33%,54%and 75%).Combined methods,e.g.,scanning electron microscopy,small-angle X-ray scattering,infrared spectroscopy(IR)and X-ray diffraction(XRD),were used to disclose howκ-carrageenan addition tailors the features of agar/KGM/κ-carrageenan ternary system.As affirmed by IR and XRD,the ternary systems withκ-carrageenan below 25%(agar/KGM/carrageenan,50:25:25,m/m)displayed proper component interactions,which increased the sol-gel transition temperature and the hardness of obtained gels.For instance,the ternary composites could show hardness about 3 to 4 times higher than that for binary counterpart.These gels were dehydrated to acquire ternary composites.Compared to agar/KGM composite,the ternary composites showed fewer crystallites and nanoscale orders,and newly-formed nanoscale structures from chain assembly.Such multi-scale structures,for composites withκ-carrageenan below 25%,showed weaker changes with RH,as revealed by especially morphologic and crystalline features.Consequently,the ternary composites with lessκ-carrageenan(below 25%)exhibited stabilized elongation at break and hydrophilicity at different RHs.This hints to us that agar/KGM/κ-carrageenan composite systems can display series applications with improved features,e.g.,increased sol-gel transition point.

Recommendations for Sustainable Development of Selenium-enriched Functional Agriculture in Guangxi under the New Normal

Taking Scientific Outlook on Development as the guiding principle,this paper introduced the principles of innovation,coordination,green,openness and sharing. Based on gifted advantages of selenium-enriched soil and selenium-enriched industry development in Guangxi,it discussed current practice,stressed green,ecological,characteristic demonstration,transformation and upgrading,and targeted poverty alleviation. Finally,it came up with perspective,practical,and operational strategies and recommendations for development of selenium-enriched industry,to provide reference for sustainable development of selenium-enriched functional industry in Guangxi.

Effect of Soil Selenium on Nutritional Quality of Vegetables in the Selenium-enriched Areas of Qinghai Plateau

In order to improve the added value of the main vegetable products in Qinghai Province,we researched the effect of soil selenium content on vegetable quality in selenium-enriched area of Qinghai. Through the analysis of Qinghai selenium-enriched soil selenium content and5 kinds of main vegetables corresponds to the total selenium,part of the mineral elements and soluble sugar and VC content,the effects of soil selenium levels on selenium absorption and nourishment quality of vegetables were researched. The results showed that he Qinghai selenium-enriched soil selenium content in the range of 100. 00-563. 00 μg/kg,among them,the soil samples with sufficient selenium and rich selenium accounted for 76. 53% and 18. 88%,respectively. Soil selenium content of garlic sampling area was relatively high,and soil selenium content of sugar beet sampling area was relatively low. Vegetable selenium content was in the range of 11. 00-340. 94 μg/kg,the average content of total selenium content of garlic was up to 170. 40 μg/kg,and the average content of the total selenium content of radish is 73. 00 μg/kg.90. 63% of the vegetables in the region reached the level of sufficient selenium,and 70. 31% reached the level of selenium enrichment. The average content of Ca and Mg was higher than the national average. There was no significant correlation between selenium content of soil and vegetable and nutritional quality.

Effect of carboxymethyl konjac glucomannan coating on curcumin-loaded multilayered emulsion:stability evaluation

The stability against various environmental stresses of the curcumin-loaded secondary and tertiary emulsions that was emulsified by whey protein isolate(WPI)and coated by chitosan(CHI),carboxymethyl konjac glucomannan(CMKGM),or their combination through layer-by-layer assembly was investigated.Generally,the multilayered emulsions were destabilized in high Na Cl concentrations or medium p H that could interrupt the electrostatic interaction between the three polyelectrolytes or deprotonate CHI,indicating that electrostatic interaction played an important role in the stability of emulsions.Compared with the primary emulsion that was solely stabilized by WPI,extra coating with CHI and CMKGM generally increased the stability of the emulsion against repeated freezing-thawing,improved the retention of curcumin against heating,UV irradiation,and long-term storage,and the effects were more remarkable in the tertiary emulsion with CMKGM locating in the outmost layer.Since CMKGM has shown the colon-targeted delivery potency,the multilayered emulsions assembled by layer-by-layer deposition,especially the tertiary emulsion,could be used as an effective carrier for the targeted delivery of curcumin.

Research Progress in Biological Control of Soft Rot of Amorphophallus konjac

In this paper,the main control methods of soft rot of Amorphophallus konjac are reviewed,with a focus on the current research status of using plant growth promoting rhizobacteria for biological control of soft rot of A.konjac,and future research directions are looked forward to.

魔芋果蔬健康代餐粉的功能特性

研究了不同杀菌条件对自制代餐粉功能特性及产品品质的影响,紫外冷杀菌可以最大限度地保留代餐粉原来的功能特性,但是杀菌效率不高;而射频杀菌既可以保留功能性成分又可以取得良好的杀菌效果。将自制代餐粉与市售代餐粉进行对比,结果表明自制代餐粉总酚质量分数及抗氧化活性均高于市售代餐粉,且自制代餐粉的风味滋味均优于市售代餐粉。为研究自制代餐粉的贮藏稳定性,对自制代餐粉进行了3个月的贮藏实验。结果表明,自制代餐粉在90 d的贮藏期内功能特性、微生物指标均在标准范围内。为了延长代餐粉的保质期,应尽可能将代餐粉置于干燥、阴凉处贮藏。

魔芋甘露低聚糖增强肠道屏障功能改善酒精性中枢神经损伤的实验研究

目的慢性酒精摄入导致的大脑过度神经炎症是中枢神经损伤的重要危险因素。本实验主要研究魔芋甘露低聚糖(Konjac mannan oligosaccharides,KMOS)保护酒精喂养小鼠中枢神经炎症的作用及其机制。方法C57BL/6J小鼠采用Gao-binge法制备慢性酒精喂养小鼠模型,同时使用不同剂量的KMOS灌胃干预,喂养6周。评估脑组织皮层和海马区域神经元损伤和小胶质细胞活化情况,观察结肠组织损伤情况和炎症反应,检测血清LPS浓度。体外使用LPS直接刺激Caco-2细胞制备肠黏膜损伤模型。结果慢性酒精的摄入可导致小鼠大脑神经元损伤,而不同剂量的KMOS均能有效降低酒精喂养小鼠脑组织中小胶质细胞的活化状态,降低NLRP3炎性小体活化导致的炎性因子表达,减轻神经元受损。对结肠组织的分析结果表明,KMOS的使用有效地降低了酒精喂养小鼠外周血中内毒素LPS的浓度,减轻酒精喂养小鼠结肠组织的病理损伤和炎性反应,增强肠道组织Occludin表达。体外实验也显示,KMOS能显著抑制酒精暴露下Caco-2细胞的炎性反应,显著提高Occludin表达水平。结论KMOS的使用可有效的抑制酒精摄入导致的肠道炎症,修复肠道屏障,减少肠道LPS进入脑组织,降低小胶质细胞活化导致的过度神经炎症反应,进而改善脑神经元损伤。KMOS具有预防酒精性神经损伤的潜力。

不同干燥条件对白魔芋精粉性质的影响及其结构表征

为了研究不同干燥条件对白魔芋精粉性质的影响,该研究以新鲜白魔芋为原料,探讨自然干燥、真空冷冻干燥、热风干燥(低温干燥、高温干燥、分段干燥)5种不同的干燥条件对白魔芋精粉色泽、魔芋葡甘聚糖(konjac glucomannan,KGM)含量、乙酰基含量、流变学性质等特性的影响,并通过分子质量、红外光谱(Fourier transform infrared spectrometer,FT-IR)、X-衍射(X-ray diffraction,XRD)、扫描电镜(scanning electron microscope,SEM)进行结构表征。结果表明,自然干燥效率低,所得样品品质较差,真空冷冻干燥虽然能得到较高品质的样品,但对设备要求比较高,干燥效率低。综合考虑,使用100℃→60℃的热风分段干燥为最佳方法,此时得到的魔芋精粉KGM含量为64.63%、乙酰基含量为23.49%、分子质量为1102 kDa、色泽较好、结晶度高、颗粒完整且表面光滑,所得水溶胶具有较好的流变学性质。综上,分段干燥方式可以用于白魔芋及其他魔芋的干燥中,所得的魔芋精粉品质良好,为白魔芋的开发应用及干燥工艺提供一定的理论参考。

魔芋凉粉的配方及工艺优化

选用红薯淀粉和魔芋粉为主要原料,以感官评分及质构参数为实验指标,通过单因素试验考察红薯淀粉添加量、魔芋粉添加量、加热温度、加热时间对产品感官及质构的影响,并选择正交试验来优化魔芋凉粉的配方及工艺.结果表明,产品的最佳配方为(以产品质量计):红薯淀粉16 g/100g、魔芋粉0.5 g/100g、纯净水83.5 mL;最佳工艺条件为:加热温度为100℃、加热时间为11 min.该条件下制备的凉粉产品质地细腻,表明光滑,弹性好,不粘牙,质构特性较好,综合评分为87.4分.

基于磷酸酯化魔芋葡甘聚糖的热可逆凝胶性能

采用真空-微波辅助半干法处理魔芋葡甘聚糖(konjac glucomannan,KGM)获得不同取代度(degrees of substitution,DS)磷酸魔芋葡甘聚糖酯(konjac glucomannan phosphate ester,KGMPs)。研究KGM和KGMP_(1)(DS 0.046)、KGMP_(2)(DS 0.131)、KGMP_(3)(DS 0.201)分别与卡拉胶复配并添加KCl(KGMPs-KC)加热-冷却形成的热可逆凝胶特性及阴阳离子和蔗糖对KGMP_(3)流变性能的影响。红外光谱分析结果表明,KGMPs与卡拉胶复配并添加KCl协同增效形成凝胶;动态黏弹流变特性结果表明,KGMPs与卡拉胶复配在KCl存在下可形成热可逆凝胶,与KGM相比,随着DS增加,KGMP复配体系形成凝胶温度逐渐降低;质构分析结果表明,28℃贮藏10 d,KGMP_(1)-KC和KGMP_(2)-KC形成凝胶硬度更好;析水性和透光率方面,KGMP_(3)-KC更具优势,适合高透明度果冻类凝胶的制备。KGMP_(3)的黏度和假塑性受到阴阳离子类型和价态的影响,其中NaH_(2)PO_(4)对KGMP溶胶影响最显著,CaCl 2次之;蔗糖能使KGMP的零表观黏度(η0)降低,但随着体系中蔗糖含量的增加,η0增加。该研究为KGMP用于高保水、高透明度、软凝胶型产品的加工提供理论和生产依据。

壳聚糖-魔芋葡甘聚糖复合絮凝剂在印染污水处理中的应用

利用改性-交联的方法制备壳聚糖/魔芋葡甘聚糖复合絮凝剂,以亚甲基蓝为例,对印染废水进行处理。探究了壳聚糖/魔芋葡甘聚糖复合絮凝剂的用量、吸附时间以及pH值对印染污水吸附率的影响。结果表明:在常温条件下,亚甲基蓝溶液初始浓度为8.0 mg/L,溶液PH为9,壳聚糖/魔芋葡甘聚糖复合絮凝剂的投加量为0.3 g,吸附时间72 h,亚甲基蓝溶液吸附率达到98.90%。

魔芋优质轻简高效栽培实用技术

魔芋大多集中种植于我国的云贵川渝地区及邻近的湖北、陕西等偏远山区,耕地单块面积小,地形情况复杂,存在栽培管理粗放、机械化应用率低、用工多、生产成本高等问题。集成旋耕机整地、起垄机起垄、履膜机覆膜、手动施肥器追肥等魔芋生产中主要工序机械化,在提高生产效率和减轻劳强度方面具有重要意义;同时通过在厚5~10μm的地膜上覆厚度为3~5 cm的土,让魔芋从膜中自然钻出,省去破膜和后期除草工序,大幅度减少了用工成本,667 m^(2)用工量由原来的20个减至10个左右。

临界熔融协同冻融处理对木薯淀粉/魔芋胶复配物理化及结构特性的影响

以木薯淀粉(cassava starch,CS)和魔芋胶(konjac gum,KGM)为原材料,以“临界熔融-冻融”(critical melting and freeze-thawing,CMFT)为主要手段制备CS/KGM复配物,研究了临界熔融协同冻融处理对CS/KGM复配物理化性质及结构特性的影响。结果表明:CMFT有效促进了可溶性淀粉组分的释放,显著增加了其与KGM相互作用的位点。所制备的复配物耐热加工特性显著提升(溶解度、膨胀度显著降低),其中熔融起始温度从64.13℃(天然)增加至69.73℃(0.7%KGM,P<0.05)。CMFT还显著改善了复配物的糊化特性,其中崩解值从1246.00 mPa·s(天然)显著下降至949.12 mPa·s(0.7%KGM),而最终黏度从2182.00(天然)显著提高至2447.00 mPa·s(0.7%KGM,P<0.05)。此外,CMFT显著增加了复配物的相对结晶度(从22.19%增加到25.50%,P<0.05),表明复配物内部结构相对致密。较高浓度的KGM添加一定程度上促进了CMFT处理中CS与KGM间的协同作用。综上,该研究证明CMFT可通过部分弱化淀粉颗粒结构和释放可溶性淀粉组分增强CS/KGM协同作用,使所制备的复配物具有显著提高的耐热加工特性及糊化特性,并有望作为功能性复配材料应用到食品加工中。

低浓度乙醇对魔芋葡甘聚糖理化特性及其结构影响的研究

为探究在低浓度乙醇下魔芋葡甘聚糖(konjac glucomannan,KGM)的性能和结构变化,拓宽其在食品领域的应用,以粗制魔芋葡甘聚糖为对象,研究其在低浓度乙醇纯化下的凝胶强度、黏度和结构的变化。结果表明,随着乙醇浓度增加和洗脱时间的延长,凝胶强度和黏度都呈现先上升后降低的趋势;随着洗脱次数的增加,凝胶强度和黏度呈现上升趋势。乙醇浓度33%(体积分数)纯化粗制魔芋葡甘聚糖30 min,洗脱2次后,与未经纯化处理KGM相比,凝胶强度和黏度分别显著提升了28.6%和34.7%。根据结构表征可知,粗制魔芋葡甘聚糖经过低浓度乙醇处理后,分子间氢键作用力增强,相对结晶度增高,局部形成有序的短程结构;同时平均粒径变化幅度不大,大小约为270.4μm;且KGM表面所含杂质减少,呈现规则的层状和褶皱分布。因此,通过调控低浓度乙醇纯化条件,可制得适应不同加工需求的KGM。

响应面法优化魔芋葡甘聚糖的纯化工艺

魔芋粉中脂肪、蛋白质等限制魔芋葡甘聚糖的应用,因此对魔芋粉进行纯化处理得到纯度更高的魔芋葡甘聚糖应用于食品、药品等产业。本研究采用乙醇作为溶剂,对利用超声波辅助纯化魔芋粉的工艺进行优化。经过单因素实验分析料液比、乙醇浓度、超声时间、超声功率、超声温度5个相关因素的显著性,选择料液比、乙醇浓度和超声时间为较显著的因子进行分析。而后通过响应面拟合模型对各相关因素进行优化,最终确定在料液比1:102(g/mL)、乙醇浓度73%、超声时间55 min、超声功率175 W、超声温度50℃条件下,魔芋葡甘聚糖含量为88.1%,与预测值相近,纯化工艺切实可行。利用红外光谱仪和X射线衍射仪测定优化前后样品结构,未发现明显差异。经该工艺纯化后的魔芋粉中魔芋葡甘聚糖含量明显高于未纯化魔芋粉,且结构受影响较小,本文旨在为魔芋葡甘聚糖的高效开发和利用提供理论依据。

辐照降解魔芋葡甘聚糖产物的制备及结构表征

为促进魔芋葡甘聚糖(KGM)降解产物的高效利用,本研究围绕辐照对魔芋葡甘聚糖(KGM)降解产物的影响展开,比较不同辐照剂量处理下魔芋葡甘聚糖(KGM)分子量、特征黏度、可溶性糖含量、电化学特性、外观色泽、微观及化学结构、晶体结构的变化。结果表明,与未辐照处理相比,KGM辐照降解产物的主链结构未改变,结晶区减弱;随着辐照剂量的增加,分子质量从未辐照处理的894.6 kDa降至32 kGy辐照处理的4.70 kDa,特征黏度及可溶性总糖含量降低;扫描电子显微镜结果显示,辐照降解产物呈片状且出现孔洞,组间Zeta电位差异显著。本试验结果可为KGM辐照降解改性和资源高效利用提供参考。