Studies on BN rats model to determine the potential allergenicity of proteins from genetically modified foods

AIM： To develop a Brown Norway （BN） rat model to determine the potential allergenicity of novel proteins in genetically modified food. METHODS： The allergenicity of different proteins were compared, including ovalbumin （OVA）, a potent respiratory and food allergen, bovine serum albumin （BSA）, a protein that is considered to have a lesser allergenic potential, and potato acid phosphatase （PAP）, a non-allergenic protein when administered to BN rats via different routes of exposure （intraperitoneally or by gavage）. IgG and IgE antibody responses were determined by ELISA and PEA, respectively. An immunoassay kit was used to determine the plasma histamine level. In addition, possible systemic effect of allergens was investigated by monitoring blood pressure. RESULTS： OVA provoked very vigorous protein-specific IgG and IgE responses, low grade protein-specific IgG and IgE responses were elicited by BSA, while by neither route did PAP elicit anything. In either routes of exposure, plasma histamine level in BN rats sensitized with OVA was higher than that of BSA or PAP. In addition, an oral challenge with BSA and PAP did not induce any effect on blood pressure, while a temporary drop in systolic blood pressure in few animals of each routes of exposure was found by an oral challenge with OVA. CONCLUSION： BN rat model might be a useful and predictive animal model to study the potential allergenicity of novel food proteins.

Nanostructured food proteins as efficient systems for the encapsulation of bioactive compounds

Recently,nanoencapsulation was introduced as an efficient and promising approach for the protection,delivery,and site-specific liberation of the nutraceuticals and bioactive ingredients.Food proteins are attractive materials for developing nanocarriers to protect and deliver bioactives due to their unique functional and biological properties.Food proteins extracted from animals and plants have the ability to form different nanostructures including nanoparticles,hollow particles,nanogels,nanofibrillar aggregates,electrospun nanofibers,nanotubular structures,and nanocomplexes.These nanostructured food proteins have been widely used as nanocarriers for the biologically active compounds and drugs.The release of bioactive compounds from nanocarriers depends mainly on pH as well as swelling and the degradation behavior of nanostructure in the simulated physiological conditions.This review presents the applications of the nanostructured food proteins for the encapsulation of bioactive compounds.The major techniques for the fabrication of nanocarriers are described.The encapsulation,protection,and release of bioactive compounds in different nanostructured food proteins were also discussed.

Progress and Application of Plastein Reaction in Food Proteins

Plastein reaction is considered a reversal of the usual protein hydrolysis by proteinase, which was applied to prepare a higher-molecular, protein-like substance. It can improve biological value and functional properties of food proteins, meliorate flavor of protein hydrolysates and, especially, provide a way to synthesize new sources of proteins. Although the mechanism（s） of the plastein reaction is not clarified, it will have great values in food industry with the development of technologies in enzymology and microbiology.

Chemical Modification of Food Proteins

Acylation has been shown to be an effective toolfor improving surface functional properties of plant proteins.Soy bean protein has been extensively modified throughchemical and enzvmatic treatments.Their effectiveness lies intheir high nutritional value and low cost,which promotetheir use as ingredients for the formulation of food products.This paper reports a complete review of chemical modificationof various proteins from plant and animal sources,The nutri-tive and toxicological aspects through in vitro and in vivotests are also described.

Protein Quality Evaluation of Animal Food Proteins by <i>In-Vitro</i>Methodologies

Animal protein foods are undoubtedly among the most concentrated source of essential amino acids (AA) for the human diet. However, their high prices and diseases associated to their excessive consumption have fomented the consumption of other alternative sources of animal proteins such as those from marine or aquatic species. Sonora is a well recognized producer of animal foods in Mexico, both terrestrial and aquatic. In this study, the protein quality evaluation of these animal food sources, highly produced and consumed in Sonora, is proposed, using in-vitro methodologies. Four different species, from each aquatic and terrestrial origin, were selected. Samples of lean muscle were used in all cases. Various in-vitro methodologies for protein quality evaluation were selected, alternatives to the animal bioassays: % digestibility, Total amino acid analyses (HPLC), PDCAAS, computerized PER calculations (C-PER and DC-PER) and total collagen contents. % in-vitro digestibility presented significant differences among samples from terrestrial species, but muscle from aquatic species did not showed significant differences. All sources of proteins, both aquatic and terrestrial proved to be rich sources of essential amino acids. PDCAAS was unable to establish significant differences in protein quality among sources of protein from different origin. Both methods C-PER and DC-PER were more exact in their results and were able to detect significant differences among samples of different origin. An important finding was the great difference in the total collagen content between aquatic and terrestrial sources of proteins, where terrestrial muscle proteins had almost 10-time more collagen than aquatic protein sources. However, these collagen contents did not seem to have a significant influence in the protein quality of these animal proteins. These muscle proteins, from both aquatic and terrestrial species, confirmed to have a high protein quality and some of the in-vitro methodologies used in this study represent a valuable alternative to the animal bioassays.

New development of whey protein products as nutritional food ingredients

Whey protein products provided ideal ingredients for nutritional food applications.Whey proteins are known to have high nutritional quality due to their high content of essential amino acids,high digestibility and biological value.Research in the past decades has shown that many of the whey protein fractions and peptides derived from them possess various biological activities.The technology developments in the last decade,such as those in the areas of protein fractionation technologies have made industrial scale production of fractionated whey protein products commercially feasible.The development in hydrolysis technology and the peptide analytical capability allowed production of whey protein hydrolysates with designed bioactivity and functionalities.People are continuously finding new biological activities of the various whey protein fractions or their hydrolysis products.Significant amount of research has also been carried out to study the clinical benefits of some of the whey protein fractions and whey protein derived peptides.Examples of these studies will be reviewed and discussed.

Analysis of Nutrient Profile of Finger Millet(Eleusine coracana(L.)Gaertn.)for Baby Food Formulation Using Pigeon Pea(Cajanus cajan(L.)Millsp.)as Protein Source

Finger millet(Eleusine coracana(L.)Gaertn.)is a drought resistant crop with potentially tremendous but under-explored source of nutraceutical properties as compared to other regularly consumed cereals in the era of drawback of nutritional security,these characteristics must be harnessed to develop finger millet as a novel functional food.Under-nutrition caused by inadequate diets,and other factors that influence nutritional status,is the underlying factor in 45%child deaths.In Kenya only 25%of young children are fed adequately diverse diets.The main objective of this study was to prepare baby food formulas using finger millets with pigeon peas as protein source and to analyze their nutritional profiles.Two finger millets varieties(i)Snapping Green Early,low altitude and medium altitude varieties and(ii)U-15)were studied to determine effects of environment on nutrient profiles.This study showed that Snapping Green Early had better nutrient profiles(12.13%protein and is high in Ca,Mg,Fe,Zn and P)than U-15(11.69%protein and lower nutrients(Ca,Mg,Fe,Zn and P)),and hence was selected for use in the malting process as best variety.As expected,the pigeon peas had the highest protein value(21%).The samples malted for 72 h resulted in reduction of tannin concentration from 0.091%to 0.03%and the amount of nutrients(Ca,Mg,Fe and Zn)doubled and in fact the protein profile increased by 8.31%.The appropriate ratio for the formulation of the baby food was 70:30.The composting resulted in 18.5%increase in protein.

Sensory and Nutritional Properties and Stability of Formulated Organic Food Flavour Enhancers

Most food flavours have been shown to contain high quantities of cooking salt, followed by flavour enhancers such as sodium glutamate, disodium inosinate, disodium guanylate and hydrogenated oils. Excess of these substances is associated with cardiovascular diseases and neurodegenerative disorders. In an effort to reduce the harmful effects of these synthetic substances, this study therefore aimed to formulate organic, nutritious food flavours with good storage stability from less harmful locally available food ingredients. A survey was carried out in 130 households and restaurants in the city of Yaoundé Cameroon, in order to evaluate the level of consumption of industrial flavours. Certain ingredients such as prawns, onions, garlic, white peppers, gingers and salt were used in some households as organic flavours. These ingredients and others were used to prepare 5 organic flavours. Their sensory and nutritional analyses and stability to storage within 90 days were evaluated. The survey revealed that 74.6% of respondents consume industrial flavours, with the cube flavour being the most widely consumed (81%). Two of the 5 organic flavours (434 and 634) had highest scores for general acceptability. The nutritional analyses of the formulae retained (434 and 634), showed that they contained: 11.08% and 10.68% fresh weight for moisture, 47.63% and 43.53% protein, 16.52% and 13.62% lipids, 2.20% and 2.44% fibres, 11.69% and 16.39% carbohydrates. Formula 434, the most accepted, had higher contents of Ca (257.97), Mg (115.91), K (1163), Zn (2.98), Cu (1.02) and Fe (12.43 mg/100g DM) while the second (634) had higher contents of sodium (3270.48) and manganese (2.18 mg/100g). Their water activity during storage in polypropylene bags for 90 days ranged from 0.39 - 0.58 at a temperature of 26.6˚C - 37˚C. The oxidative stability (90 days), determined by the acid and peroxide indices, was 9.18 - 14.13 mg KOH/g and 1.98 - 6.46 meq O2/Kg, respectively indicating good stability for 90 days of storage. The high levels of proteins and minerals in our two products justify their umami taste and can be used as highly nutritional food flavour enhancers to prevent cardiovascular diseases, especially in the elderly.

Utilization of Small Size Bolti (<i>Talibia nilotica</i>) and Sardine (<i>Sardina pilchardus</i>) Fish in Preparing Canned Weaning Food Purees

Utilize small size of bolti and sardine fish in preparing fish based weaning foods rich in protein, essential amino acids, fat high in omega 3 fatty acids, minerals and vitamins was investigated. The proximate composition, nutritional value, physical and sensorial properties were evaluated, The results of the chemical composition showed that the moisture content of fish based weaning food purees ranged from 67.73% to 72.05%. On dry weight basis, the five prepared formulations considered rich in protein (37.39% - 44.86%), fat (26.55% - 30.43%), ash (6.53% - 12.23%) and low in carbohydrates (20.70% - 22.18%). Using fish bones with muscles in preparing weaning food puree caused a marked rise in its content of Ca, P, Fe, and Zn levels especially in purees formulated from bolti. Weaning food purees containing sardine fish rich, in fat, were higher in vitamin A and D than those formulated from bolti one. Palmitic acid (C16:0), stearic acid (C18:0), and myristic acid (C14:0) represented the major saturated fatty acids in the prepared formulations. Weaning food purees containing sardine fish had relatively higher levels of sulfur-containing amino acids and slight lower values of lysine, alanine and glycine than these including bolti fish. The In vitro protein digestibility index (IVPDI) of the different formulations was found to be 100%. The visual colour of such products can be described as yellowish. Except hardness, the other texture characteristics;cohesiveness, springiness, gumminess, and chewiness of the weaning food purees did not significantly change. The children’s mothers accepted the appearance, flavor, and mouth feel of all weaning food purees prepared in this study.

Protein Quality of Amaranth Grains Cultivated in Ethiopia as Affected by Popping and Fermentation

The effect of popping and fermentation on protein quality of three different varieties of amaranth grains cultivated in Ethiopia was evaluated. Total lysine content of the grains was higher than that of commonly available cereals but close to that of legumes. Methionine and cysteine contents in the grains were also higher than that found in cereal and legume proteins. Percentage of total indispensable amino acids, excluding tryptophan, was 43% - 49%, which was higher than WHO reference pattern (31%). Popping resulted in 36% and 37% reduction in total lysine and cysteine contents, respectively, whereas fermentation reduced cysteine, lysine and methionine contents by 16%, 20% and 20%, respectively. From the free amino acids, histidine was the major indispensable amino acid but threonine was not detected. During popping, all free amino acids, except threonine, were reduced. On the other hand, fermentation significantly increased (p < 0.01) most amino acids except arginine, which was significantly decreased (p < 0.01), and tyrosine and glutamic acid, for which no change was observed. Popping decreased in vitro protein digestibility (IVPD) by 8.3% - 17.1% while fermentation increased IVPD by 4.8% - 7.5%. Substitution of amaranth for wheat and/or maize during complementary food formulation could contribute much to the daily requirements of indispensable amino acids of young children.

Safety Food in Celiac Disease Patients: A Systematic Review

The prevalence of Celiac Disease (CD), an autoimmune enteropathy, characterized by chronic inflammation of the intestinal mucosa, atrophy of intestinal villi and several clinical manifestations has increased in recent years. Epidemiological studies have shown that CD is very common and affects about one in 250 people. The mechanism of the intestinal immune-mediated response is not completely clear, but involves an HLA-DQ2 or HLA-DQ8 restricted T-cell immune reaction in the lamina propria as well as an immune reaction in the intestinal epithelium. Subjects affected by CD cannot tolerate gluten protein, a mixture of storage proteins contained in several cereals (wheat, rye, barley and derivatives). Gluten free-diet remains the cornerstone treatment for celiac patients. Therefore the absence of gluten in natural and processed foods represents a key aspect of food safety of the gluten-free diet. In this review, we evaluate the main studies about the safety food in CD patients.

Food processing wastewater purification by microalgae cultivation associated with high value-added compounds production——A review

Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated biorefinery(e.g.microalgae cultivation,harvesting,drying,extraction,conversion,and purification)is a critical challenge that inhibits its large-scale application.Among different nutrition(e.g.carbon,nitrogen and phosphorous)sources,food processing wastewater is a relative safe and suitable one for microalgae cultivation due to its high organic content and low toxicity.In this review,the characteristic of different food wastewater is summarized and compared.The potential routes of value-added products(i.e.biofuel,pigment,polysaccharide,and amino acid)production along with wastewater purification are introduced.The existing challenges(e.g.biorefinery cost,efficiency and mechanism)of microalgal-based wastewater treatment are also discussed.The prospective of microalgae-based food processing wastewater treatment strategies(such as microalgae-bacteria consortium,poly-generation of bioenergy and value-added products)is forecasted.It can be observed that food wastewater treatment by microalgae could be a promising strategy to commercially realize waste source reduce,conversion and reutilization.

婴儿型炎症性肠病的临床特征分析

目的分析婴儿型炎症性肠病(IO-IBD)的临床表现和实验室检查的变化特征。方法选取首都儿科研究所附属儿童医院消化内科2018年1月至2022年12月收治的27例IO-IBD患儿作为IBD组,另选取同期首都儿科研究所附属儿童医院收治的61例食物蛋白诱导的直肠结肠炎(FPIP)患儿作为对照组。比较分析两组患儿的临床表现及实验室检查指标。采用多因素logistic回归分析探讨影响IO-IBD发生的独立危险因素。结果两组患儿的性别、年龄以及临床表现(便血、腹泻的发生率)和腹泻次数比较,差异均无统计学意义(P>0.05)。在肠道超声检测方面,IBD组发生肠壁增厚和肛周病变的患儿比例均高于对照组,差异有统计学意义(P<0.05)。IBD组患儿发病到确诊时间长于对照组,体重指数低于对照组,差异有统计学意义(P<0.05)。IBD组的白细胞计数、血小板计数、C反应蛋白、红细胞沉降率、白介素-6、白介素-10水平高于对照组,而白蛋白低于对照组,差异有统计学意义(P<0.05)。采用R语言(4.3.2版本)进行多因素logistic回归分析,结果显示,校正前和校正后,白细胞计数升高,血小板计数升高、C反应蛋白升高、红细胞沉降率升高、白蛋白降低、白介素-6升高均是IO-IBD发生的独立危险因素(P<0.05)。结论临床表现为长期腹泻、便血的婴儿,应注意IO-IBD的可能,尤其是合并有营养不良、肠壁增厚、肛周病变等情况时,IO-IBD的可能性更大,建议尽早完善结肠镜检查及基因检测以明确诊断。白细胞计数、C反应蛋白、血清白介素-6和白蛋白水平可作为鉴别诊断IO-IBD与FPIP的指标。

Food restriction decreases BMR,body and organ mass,and cellular energetics,in the Chinese Bulbul(Pycnonotus sinensis)

Background: Food is an important environmental factor that affects animals' energy metabolism and food shortage has significant effects on animals' behavior, physiology and biochemistry. However, to date few studies have focused on the thermogenesis and its effects on the body condition of birds. In this study, we examined the effects of food restriction on the body mass, basal metabolic rate(BMR) and body composition, and several physiological, biochemical and molecular markers potentially related to thermogenesis, in the Chinese Bulbul(Pycnonotus sinensis).Methods: Birds in the control group were provided with food ad libitum whereas those in the food restriction group were provided with one-half of the usual quantity of food for 12 days. Oxygen consumption was measured using an open-circuit respirometry system. Mitochondrial state 4 respiration and cytochrome c oxidase(COX) activity in the liver and pectoral muscle were measured with a Clark electrode. Avian uncoupling protein(avUCP) mRNA expression was determined in pectorals muscle with quantitative Real-time PCR.Results:Chinese Bulbuls in food restriction group decreased in body mass,BMR and internal organ(heart,kidneys,small intestine and total digestive tract)mass compared with the control group over the 12-day period of food restriction.Bulbuls in the food restriction group also had lower levels of state-4 respiration,COX activity in the liver and muscle,and mitochondrial avUCP gene expression in muscle compared to the control group.BMR was positively correlated with body mass,state 4 respiration in the liver and COX activity in the muscle.Conclusions:Our data indicate that Chinese Bulbuls not only sustain food shortage through simple passive mechanisms,such as reducing body and organ mass and energy expenditure,but also by reducing energetic metabolism in the liver and muscle.

芝麻蛋白-茶多酚食品胶复合凝胶的应用特性研究

以芝麻饼粕为原料,碱溶酸沉法制备芝麻分离蛋白,加入0.1%茶多酚复合食品胶制备具有一定功能特性和凝胶性能的复合凝胶产品,并对其理化性质进行研究。通过对复合凝胶质构特性、持水能力、低场核磁、流变学特性及微观结构等方面的考察,研究加入不同比例(0.1%、0.3%和0.5%)的黄原胶、瓜尔胶、魔芋胶和卡拉胶对芝麻蛋白-茶多酚-食品胶复合凝胶特性的影响。结果表明:4种食品胶的添加可以改善复合凝胶的硬度、弹性、内聚性和胶黏性,提高持水能力。复合凝胶的流变学结果体现出较好的凝胶稳定性。凝胶的微观结构显示复合凝胶网络更加紧密,孔隙更小。茶多酚、食品胶的加入使复合凝胶的性能得到改善,为芝麻蛋白凝胶作为一种新型植物蛋白凝胶在食品工业上的应用提供理论基础。

天然皂皮皂苷与大豆分离蛋白协同构建高蛋白减脂植物基蛋黄酱及其特性

本研究利用天然皂皮皂苷(Quillaja saponin,QS)与大豆分离蛋白(soybean protein isolate,SPI)稳定乳液凝胶的协同效应构建高蛋白、减脂的植物基蛋黄酱(plant-based mayonnaise,PM)。利用静态光散射、激光共聚焦、低形变流变学和质构特性对比分析PM与两种市售蛋黄酱在外观、乳滴粒径大小与分布、硬度、涂抹性、热稳定性和冻融稳定性等方面的特性。结果表明,以10%SPI和0.18%QS或10%SPI、0.18%QS和1%SPI凝胶颗粒(soy protein isolate gel particles,SGPs)为蛋白配料可构建出与商品蛋黄酱在外观、涂抹状态、质构以及流变特性上相媲美的高蛋白减脂PM(10%蛋白质与50%脂肪、11%蛋白质与40%脂肪,以质量分数计)。在该体系中,QS不仅赋予了高蛋白乳化制品黏度稀化的质构调节性,还赋予了SPI基乳液凝胶优越的热稳定性和冻融稳定性。本研究可为“高蛋白”“减脂”PM的开发与应用提供理论与技术指导。

不同投喂频率下复合非粮蛋白源替代鱼粉饲料对大口黑鲈生长性能和健康的影响

为探究投喂频率对不同水平的复合非粮蛋白源替代饲料鱼粉对大口黑鲈(Micropterus salmoides)生长性能、血浆生化、肠道形态和抗氧化的影响,设计了棉籽浓缩蛋白、乙醇梭菌蛋白、黄粉虫粉和小球藻4种非粮蛋白源混合(8﹕5﹕3﹕4)后替代0、30%、60%和90%的鱼粉的四种等氮等脂饲料(D1、D2、D3和D4),设置3个投喂频率(1、2和4次/d)。每个处理组3个重复,每个重复50尾体重为(14.23±0.07)g的大口黑鲈幼鱼,进行为期8周的室外养殖实验。结果显示,在不同投喂频率条件下,摄食D4饲料组大口黑鲈的特定生长率(SGR)和蛋白质沉积率(PRE)显著低于D1—D3组,饲料系数(FCR)显著升高(P<0.05)。在各饲料组中,投喂1次/d组的特定生长率显著低于2和4次/d投喂组(P<0.05)。在不同投喂频率条件下,摄食D4饲料组大口黑鲈血浆胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)含量显著低于D1组,谷丙转氨酶(ALT)活性显著高于D1组(P<0.05)。在各饲料组中,投喂1次/d大口黑鲈血浆葡萄糖(Glu)含量,碱性磷酸酶(AKP)和谷草转氨酶(AST)活性显著高于2和4次/d组(P<0.05),而总蛋白(TP)和白蛋白(ALB)含量显著低于其他两组(P<0.05)。在投喂1次/d的处理组中,摄食D4饲料组的全鱼粗脂肪和血浆低密度脂蛋白胆固醇(LDL-C)含量显著降低,水分含量显著高于其他各组(P<0.05)。各投喂频率下,D4饲料组大口黑鲈肠道组织丙二醛(MDA)含量显著高于D1组,而超氧化物歧化酶(SOD)活性显著低于D2组(P<0.05)。在各饲料组中,投喂2次/d组的总抗氧化能力(T-AOC)和过氧化氢酶(CAT)活性显著高于1次/d组(P<0.05)。组织学结果显示,在摄食不同饲料条件下,投喂2次/d的大口黑鲈肠道绒毛高度、杯状细胞数量、肌层厚度和绒毛表面积显著高于投喂1次/d,投喂4次/d的大口黑鲈肠道隐窝深度显著低于1次/d(P<0.05)。综上所述,以2次/d投喂60%替代水平新型蛋白源复合饲料的大口黑鲈可以获得较好的生长和饲料利用。

婴儿牛奶蛋白过敏的危险因素:一项多中心前瞻性巢式病例对照研究

目的探讨婴儿牛奶蛋白过敏(cow'smilkproteinallergy,CMPA)发生的危险因素。方法该研究为多中心前瞻性巢式病例对照研究。选取北京市7家医学中心0~12月龄婴儿为研究对象。共纳入CMPA婴儿200例,未发生CMPA的婴儿(对照组)799例。采用单因素和多因素logistic回归分析探讨CMPA发生的危险因素。结果单因素logistic回归分析显示,早产儿、低出生体重儿、第一胎、第一产、春季出生、夏季出生、混合/人工喂养、父母患过敏性疾病与婴儿CMPA患病风险增加有关(P<0.05)。多因素logistic回归分析显示,第一产(OR=1.89,95%CI:1.14~3.13)、春季出生(OR=3.42,95%CI:1.70~6.58)、夏季出生(OR=2.29,95%CI:1.22~4.27)、混合/人工喂养(OR=1.57,95%CI:1.10~2.26)、父亲或母亲有过敏史(OR=2.13,95%CI:1.51~3.02)、双亲有过敏史(OR=3.15,95%CI:1.78~5.56)是婴儿CMPA发生的危险因素(P<0.05)。结论第一产出生、春季出生、夏季出生、混合/人工喂养或有过敏家族史的婴儿CMPA的患病风险增加。

马铃薯乳清复合蛋白乳液凝胶的制备和特性

采用碱溶酸沉法提取了马铃薯蛋白(PP),然后以PP、乳清蛋白(WP)和大豆油为原料,制备了马铃薯乳清复合蛋白乳液凝胶,通过FTIR、低场核磁(LF-NMR)、SEM、激光扫描共聚焦显微镜(CLSM)表征,结合流变、质构、色度、分子间力测试,考察了m(PP)∶m(WP)对复合蛋白乳液凝胶特性的影响。结果表明,复合蛋白乳液凝胶综合特性要优于单一的PP或WP乳液凝胶。与m(PP)∶m(WP)=10∶0制备的PP乳液凝胶相比,m(PP)∶m(WP)=7∶3、5∶5制备的复合蛋白乳液凝胶的温度循环终点储能模量(G′)分别提高了114.75%和109.22%(P<0.05);束缚水质量分数分别提高了2.01%和1.97%(P<0.05);凝胶强度、弹性、胶黏性、恢复性和咀嚼度显著增强(P<0.05)。复合蛋白乳液凝胶网络结构紧密,凝胶网络中油滴均匀分布在蛋白凝胶网络中,起到了更好的支撑作用。β-折叠和β-转角结构是马铃薯乳清复合蛋白乳液凝胶中蛋白质的二级结构,含量合计约为70%。

食物蛋白诱导的直肠结肠炎患儿不同乳制品喂养前后肠道微生态变化的研究

目的探讨3种不同喂养方式对食物蛋白诱导的直肠结肠炎(Food protein-induced proctocolitis,FPIP)患儿喂养前后肠道微生物特点及体格发育的影响。方法以2023年1月至12月山西省儿童医院新生儿内科的60例FPIP患儿作为试验组(失访15例,最终纳入45例),根据家长意愿分为3个亚组:母乳喂养组(母亲回避牛奶、鸡蛋、坚果)(Breastfeeding group,BAM组)、深度水解配方乳喂养组(Extensively hydrolyzed formula group,eHF组)和游离氨基酸配方乳喂养组(Amino acid formula group,AAF组);以本院产科同期分娩、并于后期在儿童保健科定期随访中均未出现FPIP症状的20例健康新生儿作为对照组,采用母乳喂养和/或普通配方乳喂养。比较各组研究对象不同喂养方式前后的临床症状、肠道微生态特点及体格发育情况。结果①实验组3种喂养方式中,AAF组中FPIP患儿腹泻、便血及肉眼血便消失的时间更短,差异有统计学意义(P<0.05)。②治疗前粪便物种丰度AlPha多样性中,试验组的丰富度(Chao1 richness,Chao1)指数和利用稀有物种估算物种多样性(Abundance-based coverage estimator,ACE)指数显著低于对照组,差异有统计学意义(P<0.05)。③治疗后试验组中3组的粪便物种丰度的菌群操作分类单元(Operational taxonmic unit,OTU)及AlPha多样性差异均无统计学意义(P>0.05)。④本研究对肠道菌群的物种差异进行分类学分析,以门水平为例,治疗前试验组较对照组菌群多样性降低,以放线菌门和拟杆菌门降低为主;治疗后试验组3组中,BAM组菌群多样性更接近于对照组,差异无统计学意义(P>0.05);eHF组和AAF组与对照组相比,厚壁菌门和变形菌门占优势,差异有统计学意义(P<0.05)。⑤试验组3组患儿治疗5个月后的体重、身长差异均无统计学意义(P>0.05)。结论游离氨基酸配方乳在治疗FPIP时,临床效果更好;FPIP患儿菌群多样性较健康婴儿降低;母乳喂养(母亲回避牛奶、鸡蛋、坚果)更有利于FPIP婴儿后期健康肠道菌群的建立;母亲回避饮食的母乳喂养、深度水解配方乳喂养和游离氨基酸配方乳喂养对后期体格发育影响差异不大。