Efficacy of Raw Corn Starch in Insulinoma-Related Hypoglycemia:A Promising Supportive Therapy

Objective To investigate the efficacy of raw corn starch(RCS)in clinical management of insulinoma-induced hypoglycemia.Methods We retrospectively collected clinical data of insulinoma patients who received RCS-supplemented diet preoperatively,and analyzed the therapeutic effects of the RCS intervention on blood glucose control,weight change,and its adverse events.Results The study population consisted of 24 cases of insulinoma patients,7 males and 17 females,aged 46.08±14.15 years.Before RCS-supplemented diet,all patients had frequent hypoglycemic episodes(2.51±3.88 times/week),concurrent with neuroglycopenia(in 83.3% of patients)and autonomic manifestations(in 75.0% of patients),with the median fasting blood glucose(FBG)of 2.70(interquartile range[IQR]:2.50-2.90)mmol/L.The patients'weight increased by 0.38(IQR:0.05-0.65)kg per month,with 8(33.3%)cases developing overweight and 7(29.2%)cases developing obesity.All patients maintained the RCS-supplemented diet until they underwent tumor resection(23 cases)and transarterial chemoembolization for liver metastases(1 case).For 19 patients receiving RCS throughout the day,the median FBG within one week of nutritional management was 4.30(IQR:3.30-5.70)mmol/L,which was a significant increase compared to pre-nutritional level[2.25(IQR:1.60-2.90)mmol/L;P<0.001].Of them,10 patients receiving RCS throughout the day for over four weeks had sustained improvement in FBG compared to pre-treatment[3.20(IQR:2.60-3.95)mmol/L vs.2.15(IQR:1.83-2.33)mmol/L;P<0.001].Five patients who received RCS only at night also had a significant increase in FBG within one week of nutritional management[3.50(IQR:2.50-3.65)mmol/L vs.2.20(IQR:1.80-2.60)mmol/L;P<0.001],but only one patient who continued to receive RCS for over four weeks did not have a significant improvement in FBG.No improvement in weight gain was observed upon RCS supplementation.Mild diarrhea(2 cases)and flatulence(1 case)occurred,and were relieved by reduction of RCS dose.Conclusion The RCS-supplemented diet is effective in controlling insulinoma-induced hypoglycemia.

Drying kinetics of soy protein isolate-corn starch film during preparation and its moisture adsorption characteristics during storage

To better understand the mass transfer process of moisture in the soy protein isolate-corn starch(SPI-CS)films during preparation and storage process,the drying kinetics model of SPI-CS films with different formation conditions during the drying process and the moisture adsorption characteristics of the SPI-CS films under different humidity conditions were investigated.Within the range of experimental conditions,the moisture migration rule in the SPI-CS films during the drying preparation was combined with the Page model which was expressed as MR=exp(-kt^(n)).It was found that the adsorption equilibrium needed shorter time(about 3 h)when the SPI-CS films existed in the environment with lower humidity(RH<54%).Additionally,the secondorder adsorption kinetic equation was successful to describe the moisture adsorption characteristic of the SPICS films during storage under different humidity conditions.

Production of Corn (Zea mays) Starch and Cassava (Manihot esculenta) Starch and Their Application as Yogurt Stabilizer

The present study evaluated the stabilizing effect of starch produced from corns and cassava on the stability of cow milk yogurt. A sample of both corn and cassava starch was selected and used in the yogurt making as stabilizers. The yogurt samples have been analyzed for their WHC, syneresis and protein content. The yogurt with no added starch has found to have very low WHC and high syneresis compared to other samples. The yogurt made with the addition of corn starch as a stabilizer was highly accepted than the yogurt with cassava starch and the yogurt without starch. The findings from this study provide an alternative to add the value of local corns and cassava.

Corn Starch Derived Capacitive Carbon Prepared by One-Step K2CO3 Carbonization for Supercapacitors

High-performance carbonaceous electrode materials for supercapacitors were synthesized by subjecting corn starch to a simple molten salt activation process with K2CO3 at a temperature of 850˚C. The resulting carbon material, obtained after activating for 1 hour, displayed excellent capacitive properties due to the synergistic effects of its porous structure. Utilizing these electrodes, the supercapacitor exhibited a high discharge capacitance (248 F g−1 at 1 A g−1), which is 2.4 times higher than that of activated carbon without K2CO3 activation. The enhancement in electrical performance was analyzed through SEM and XRD analysis, revealing that the porous and disordered structure provides a greater number of charge storage sites, resulting in improved capacitive performance.

Physicochemical Properties Comparative Analysis of Corn Starch and Cassava Starch, and Comparative Analysis as Adhesive

The morphology and properties of corn starch and cassava starch were compared by SEM, DSC and TGA. Theeffects of amylose and amylopectin content on starch properties were studied by FT-IR, XRD and XPS. The plywood was pressed with the prepared adhesive and the bonding strength of the plywood was tested to analyze thedifference among the adhesives from different plant sources and the difference after blending PAPI prepolymer.FT-IR results showed that the hydroxyl peak of cassava starch was stronger and wider. TGA showed that the residue of cassava starch was lower, but the thermal stability of cassava starch was almost the same. XPS data showedthat the oxygen content of cassava starch was slightly higher, but the carbon content was slightly lower. SEM analysis showed that corn starch granules were more irregular and sharper than cassava starch, and cassava starchgranules were more uniform, regular and round.

Comprehensive utilization of corn starch processing by-products:A review

Corn is a high starchy cereal crop with the highest production and provides over 85%of the starch produced worldwide.Various by-products,differentiated by technological process features such as steep liquor,corn germ,corn bran,gluten,are created largely during corn starch processing.They are inexpensive,nutrient-rich,and vary widely in chemical composition such as proteins,oils,carbohydrates,and minerals.In an increasingly resource-constrained modern world,the utilization approach of these by-products for non-starch industrial processing is attractive widely considering both nutritive value and economic aspects.In fact,at present,applications of these by-products can often be found in feed,fermentation,nutrient extraction and other industries.For example,protein-rich corn gluten can be used as a good animal feed,and corn germ can be used as a raw material for the high-quality edible oil industry.Undoubtedly,increasing utilization means that these by-products will no longer be treated as waste but will be transformed into high value-added products.In this work,the separation process and chemical composition of several main by-products of the corn starch industry is briefly described,and the application in many industrial fields of these by-products over the last ten years are discussed in particular.This review attempts to summarize all aspects of the application and research of these by-products.For the by-products of the corn starch industry,the most promising way is to be utilized in high value and used to produce high value-added products.According to the characteristics of their chemical composition,they have a better application prospect and research significance in the industries directly related to human beings,such as medicine,green food and health care products.In fact,in recent years,some researchers have recognized this and carried out the research.It is clear fromthese studies that the main issues to be faced nowand in the future are how to produce efficiently while maintaining the quality of the product and using it effectively.The retrospective discussions also provide some ideas for other grain and oilseed crops to be fully utilized.

Study on the Properties of Esterified Corn Starch/Polylactide Biodegradable Blends

Fully bio-based and biodegradable starch/polylactic acid blends have received increasing attentions for their biodegradability and potential to offset the use of unsustainable fossil resources,specifically,their application in packaging.Herein,corn starch was first esterified with maleic anhydride and then compounded with polylactide(PLA)to prepare esterified corn starch/polylactic acid blends with starch content up to 35 wt%.The structures,morphologies,thermal and mechanical properties of starch or blends were investigated.The results showed that corn starch was successfully grafted with maleic anhydride,which showed increased crystallinity and particle size than native starch.Esterified corn starch/polylactic acid blends showed good surficial compatibility and good thermal stability with main decomposition temperature in the range of 300℃to 400℃.Additionally,incorporation of corn starch increased the hydrophilicity and water uptake of composites.However,the tensile and flexural strengths of blends decreased with increasing esterified starch amount.

Impact of Nitrogen Fertilization on the Oil, Protein, Starch, and Ethanol Yield of Corn （Zea mays L,） Grown for Biofuel Production

Nitrogen fertilization is one of the greatest challenges associated with the production of biofuel from corn grain. The objective of this research was to determine the effect of N fertilization on the content and yield of oil, protein, and starch in corn grain. The project was done in Southeast Missouri （USA）, from 2007 to 2009 in a silt loam soil. Corn grain contains 3.8-4.2% oil, 6.7%-8.9% protein, 68.0%-70.4% extractable starch, and 76.0%-77.7% total starch. The total starch yield ranged from 2.8 to 7.8 mg.ha1 whereas the extractable starch varied between 2.5 to 7.1 mg-ha1. As the N rate went up, the oil and starch content of the grain decreased, whereas the protein content and the protein, starch, and oil yields increased, reaching their maximum at the N rate corresponding to 179.0 kg N.ha~. The potential ethanol yield varied between 616.2 and 7,035.1 L-ha1 depending on the method of conversion of the starch into ethanol, the year and the N rate （P 〈 0.0001）. The negative correlation between N fertilization rate and starch content suggested that when farmers add too much N to their soil to increase grain yield, they reduce the starch content in those grains, and consequently the conversion into bioethanol. Therefore, for biofuel production to be beneficial for both farmers and the power plant owners, an agreement needs to be made with regard to the use of fertilizers.

4种植物源性成分多重real-time PCR检测方法的建立及其在食用淀粉中的应用

建立一种可同时快速检测红薯、木薯、马铃薯、玉米源性成分的多重实时聚合酶链式反应(real-time polymerase chain reaction,real-time PCR)方法。分别以红薯g3pdh基因、木薯g3pdh基因、马铃薯UGPase基因、玉米zSSIIb基因为靶基因设计特异性引物和TaqMan探针,以18S rRNA基因为内参基因,建立多重real-time PCR方法,开展方法学验证,并对不同掺入比例模拟样品和实际淀粉样品进行检测。结果显示,该方法具有高通量、特异性强、灵敏度高等优点。与15种非目标源性均无交叉反应;对目标DNA的检测灵敏度可达到3×10^(-3) ng/μL,且具有良好的线性关系和扩增效率;对淀粉样品的检出限可达0.1%,对50份实际样品进行检测,结果与参比方法一致,说明建立的多重real-time PCR法可用于食用淀粉种类掺假鉴别检测。

感应电场对普鲁兰酶解玉米淀粉结构性能和体外消化的影响

以玉米淀粉为研究对象,探讨磁感应电场对普鲁兰酶水解淀粉结构性能和体外消化的影响。结果显示,经过酶解和感应电场的处理,改性后玉米淀粉颗粒出现大量孔洞,偏光十字模糊,结晶区1 047 cm-1/1 022 cm-1升高,1 022 cm-1/995 cm-1降低,相对结晶度随着感应电压的增加而增加。直链淀粉相对含量呈现先上升后下降的趋势,当感应电压为125 V时,直链淀粉相对含量高达98.61%。溶解度和膨胀度随着施加感应电压的增强先降低再增加,硬度和内聚力呈先增加后减少的趋势。原玉米淀粉和处理淀粉的黏性随剪切速率增加而迅速减少。储存模量和损耗模量与直链淀粉的含量有一定关系。当感应电压为125 V时抗性淀粉相对含量高达62.46%。体外消化水解率和血糖指数呈现先减少后增加的趋势。本研究可为感应电场在改性淀粉的生产和开发方面提供理论参考。

聚乳酸改性糯玉米淀粉的制备及表征

以糯玉米淀粉为原料、异辛酸亚锡为催化剂,在丙交酯熔融体系中制备了聚乳酸改性糯玉米淀粉。建立了聚乳酸改性糯玉米淀粉取代度的^(1)HNMR测试方法,以取代度为响应值,反应时间、反应温度、丙交酯添加量为考察因素,通过单因素和响应面实验优化了聚乳酸改性糯玉米淀粉的合成工艺,得到最优工艺为:反应时间12.46 h,反应温度111.75℃,丙交酯添加量为淀粉质量的258%,预测最大取代度为0.0253,通过实际操作条件调整后实际取代度为0.0238。对最优条件下制备的聚乳酸改性淀粉进行了系列表征,证实聚乳酸改性糯玉米淀粉的颗粒结构没有被完全破坏,晶型、相对分子质量等性能优于溶剂法传统技术制备的聚乳酸改性糯玉米淀粉。

生产加工过程食用玉米淀粉基因降解情况

含有转基因成分的玉米在生产加工过程中核酸成分受到不同程度破坏,增加出口过程中转基因成分检验难度。针对转基因食用玉米淀粉在加工过程中主要环节进行样本收集,使用荧光定量聚合酶链式反应(polymerase chain reaction,PCR)对加工过程中样品内、外源基因不同扩增片段进行定量研究。研究发现,浸泡后的浆料湿磨及精磨分离阶段的样品DNA降解严重。随着检测转基因成分方法的不断创新和提高及数字PCR在检测领域的开发和应用,利用数字PCR方法检验痕量转基因成分,不仅可以定性检测,并且可以对转基因成分含量进行定量检测。

玉米淀粉对冷冻米线冻融品质的影响

[目的]改善米线速冻后断条率较高、浑汤严重等问题。[方法]研究了添加20%玉米淀粉对冻融循环过程中冷冻米线蒸煮品质、质构特性、感官品质、可冻结水含量、水分分布和表面微观结构的影响。[结果]添加玉米淀粉能显著提升冷冻米线冻融循环过程中的蒸煮品质,其中冻融4次后蒸煮损失和断条率分别下降了42.31%和36.97%,米汤中溶出的直链淀粉和蛋白质含量也有明显下降。加入玉米淀粉后,冷冻米线的硬度和咀嚼性分别上升了22.97%和26.57%,并且感官总评分上升了13.04%。同时,玉米淀粉的加入抑制了深层结合水向弱结合水的迁移,降低了可冻结水的含量,从而减轻了冰晶对冷冻米线的机械损伤,使其表面更加光滑致密。[结论]添加20%玉米淀粉可以提高冷冻米线的蒸煮品质和质构特性,并延缓其品质劣变趋势,同时抑制了内部水分流动性的增加,减少冰晶的生成,从而改善冷冻米线的冻融品质。

微波间歇干燥对玉米籽粒中淀粉理化特性的影响

为提高玉米干燥的速率,明确微波间歇干燥对玉米中淀粉的影响,以"吉农玉719"为研究对象,对比自然干燥和不同微波功率密度条件下微波间歇干燥对玉米中淀粉加工和结构特性的影响。结果表明:与自然干燥的玉米相比,玉米经微波干燥,其淀粉的性质发生明显变化,微波功率密度在0.9~3.6 W/g范围内,玉米淀粉的峰值黏度和溶解度均呈先升高后降低的趋势,当微波功率密度为1.8 W/g时,淀粉的峰值黏度最高,溶解度最高。静态流变学结果表明:玉米经自然干燥和微波干燥,其淀粉凝胶均为假塑性流体。动态流变学结果表明:微波功率密度在0.9~1.8 W/g范围,微波作用可明显改善玉米淀粉凝胶的黏弹性,当微波功率密度为1.8 W/g时,淀粉凝胶的黏弹性最好;当微波功率密度高于1.8 W/g时,玉米淀粉凝胶的硬度显著增加;玉米经微波干燥,其淀粉的膨胀度、热焓值和有序度均降低,粒径增加。结论:在微波功率密度1.8 W/g、微波时间2 min、缓苏时间4 min条件下干燥得到的玉米淀粉特性最佳。

循环热处理对油莎豆淀粉流变特性以及促回生特性的影响

以玉米淀粉为对照,探究油莎豆淀粉的糊化特性和流变特性,并将其进行循环回生处理,研究其对淀粉结构、热特性、水分分布和消化特性的影响。结果表明:相比于玉米淀粉,油莎豆原淀粉颗粒较小,具有较强的吸水溶胀能力,表现出较高的峰值黏度、崩解值和回生值。流变特性显示,油莎豆原淀粉的G'和G″较小,触变环面积较大,其形成的凝胶网络结构具有较弱的黏弹性和较强的流动性,且抗剪切能力略差。经循环热处理,油莎豆淀粉的糊化焓值、IR_(1047)cm^(-1)/1022cm^(-1)比率、自由水比例和慢消化淀粉、抗性淀粉含量均显著升高,其增值幅度高于同等处理条件下的玉米淀粉。在经过循环热处理后,油莎豆淀粉在偏振光下显示出较大的亮光区,而玉米淀粉则未体现出此现象,说明油莎豆淀粉在加工过程中的更强回生能力;消化结果也一致表明,与玉米淀粉对比,油莎豆淀粉表现出更高的抗消化性能,这可能是由于其分子链间更趋向于重排,并形成了更紧密的结晶结构。

超高压处理对高直链和蜡质玉米淀粉复配体系的影响研究

不同直链/支链淀粉复配以及非热加工处理是改变淀粉理化性质的有效手段。为探讨超高压处理对高直链玉米淀粉和蜡质玉米淀粉复配体系的影响,该文以不同比例复配淀粉为研究对象,研究了超高压(600 MPa/30 min)处理前后其理化性质和结构变化。结果显示,随着蜡质玉米淀粉比例的增加,复配淀粉溶解度、黏度、假塑性增加;超高压处理使复配淀粉储能模量和损耗模量增加;超高压处理后高直链淀粉与蜡质淀粉复配比例为0∶5和2∶3时,其糊化温度分别降低了15.82℃和17.62℃;超高压处理后复配淀粉的相对结晶度、短程有序性降低,其中蜡质玉米淀粉颗粒破损严重,但高直链玉米淀粉颗粒较完整;体外消化结果表明超高压处理降低抗消化淀粉含量,显著提升了慢消化淀粉含量。因此,将不同直链淀粉含量的玉米淀粉复配并加以超高压处理,可作为一种淀粉物理改性的方式,其在淀粉基凝胶领域具有较高应用价值。

ε-聚赖氨酸盐酸盐接枝淀粉薄膜的制备及性质研究

目的对淀粉接枝抑菌肽,得到抑菌淀粉,并挤出成膜,表征其性质,为淀粉的应用提供参考。方法借助偶联剂,将ε-聚赖氨酸盐酸盐(ε-polylysine-HCl,ε-PLH)接枝到玉米淀粉上,分析其化学结构、微观结构、热性能及抑菌性。通过熔融挤出法将接枝淀粉与聚乳酸(Polylactic acid,PLA)、聚己二酸/对苯二甲酸丁二酯(Poly butyleneadipate-co-terephthalate,PBAT)共混改性成膜,表征其力学性能、抑菌性能。结果FTIR显示,ε-PLH被成功接枝到淀粉分子上;热重分析(TGA)结果显示,接枝淀粉的起始分解温度有所下降;含有30%接枝淀粉的PBAT/PLA薄膜具有更高的拉伸强度。此外,接枝淀粉添加量为30%的薄膜对大肠杆菌、金黄色葡萄球菌的抑制率分别达到了46.53%、68.81%。结论接枝ε-聚赖氨酸盐酸盐是一种有效的淀粉改性途径,接枝淀粉/PBAT/PLA薄膜具有良好的应用前景。

氧化玉米淀粉/明胶复合胶囊壳的制备与表征

目的:采用改性淀粉与明胶共混制备胶囊壳,降低胶囊壳制备成本。方法:以玉米原淀粉为原料,采用15%用量的过氧化氢氧化制备氧化玉米淀粉,与明胶共混,分别通过流延法和浸渍法制备了氧化玉米淀粉/明胶复合胶囊膜和胶囊壳,并采用傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)、扫描电子显微镜(SEM)对其进行表征。结果:当氧化玉米淀粉与明胶质量比为5∶5,制备的氧化玉米淀粉/明胶复合胶囊壳的干燥失重在13.0%~15.0%,在蒸馏水和模拟人工胃液中的崩解时限在10 min以内,脆碎度不超过5粒。结论:采用氧化玉米淀粉与明胶共混制备的复合胶囊壳性能符合《中国药典》(2020)要求。

制备工艺对高直链玉米淀粉—硬脂酸复合物性质的影响

[目的]优化高抗性淀粉(RS)含量的淀粉—脂质复合物制备工艺,探究工艺参数对复合物抗消化性的影响。[方法]采用单因素试验和正交设计研究了高直链玉米淀粉(HA)预处理及其与硬脂酸(SA)络合过程中温度和时间参数对复合物RS含量的影响,分析最优工艺制备的HA-SA复合物的理化性质、抗消化性及水合特性。[结果]在糊化温区继续升高预处理温度、延长预处理时间、络合温度高于75℃均导致RS含量显著降低(P<0.05);HA-SA复合物最优制备工艺为:HA经85℃的退火温度预处理12 h后,在75℃与SA络合90 min;所制备的HA-SA具有V型晶体特征、完整的淀粉颗粒,为Ⅰ型淀粉—脂质复合物;与HA相比,其热稳定性、抗消化性显著升高,但膨胀力显著降低(P<0.05)。[结论]退火温度预处理和适宜的络合温度有利于HA-SA中RS组分的形成;预处理过程中加热强度的增加使淀粉过度糊化,阻碍了直链淀粉与脂质的络合,络合过程中过高的温度也导致复合物中RS组分的解离,使RS含量降低;退火预处理使HA保留了完整的颗粒结构,是HA-SA抗消化性高的原因之一。

高强度纳米甲壳素复合淀粉水凝胶的制备及其特性研究

以玉米淀粉为原料制备纳米甲壳素复合淀粉水凝胶,探究复合淀粉水凝胶的微观结构、流变特性、溶胀特性和抑菌性。结果表明:以玉米淀粉质量为基准,当纳米甲壳素添加量为15%时,制备的复合淀粉水凝胶特性效果最好,其硬度提高了约0.5倍;在角频率为20rad/s时,其储能模量(G′)增加了42.4%;当剪切速率为20s^(-1)时,其表观黏度提高了48%。微生物试验表明,在直径2.0cm范围内,与玉米淀粉水凝胶相比,纳米甲壳素添加量为20%的复合淀粉水凝胶使酿酒酵母菌菌落数减少了70%,大肠杆菌菌落数减少了60%。