Branched-chain amino acids to tyrosine ratio value as a potential prognostic factor for hepatocellular carcinoma

The prognosis of hepatocellular carcinoma(HCC) depends on tumor extension as well as hepatic function.Hepatic functional reserve is recognized as a factor affecting survival in the treatment of HCC;the ChildPugh classif ication system is the most extensively used method for assessing hepatic functional reserve in patients with chronic liver disease,using serum albumin level to achieve accurate assessment of the status of protein metabolism.However,insuff icient attention has been given to the status of amino acid(AA) metabolism in chronic liver disease and HCC.Fischer's ratio is the molar ratio of branched-chain AAs(BCAAs:leucine,valine,isoleucine) to aromatic AAs(phenylalanine,tyrosine) and is important for assessing liver metabolism,hepatic functional reserve and the severity of liver dysfunction.Although this ratio is diff icult to determine in clinical situations,BCAAs/tyrosine molar concentration ratio(BTR) has been proposed as a simpler substitute.BTR correlates with various liver function examinations,including markers of hepatic f ibrosis,hepatic blood flow and hepatocyte function,and can thus be considered as reflecting the degree of hepatic impairment.This manuscript examines the literature to clarify whether BTR can serve as a prognostic factor for treatment of HCC.

Early administration of branched-chain amino acid granules

The effect of malnutrition on survival in patients with decompensated liver cirrhosis has not been well defined. Nutritional intervention with branched-chain amino acid (BCAA) can increase serum albumin concentration in patients with decompensated cirrhosis but its effects on survival are unclear. The BCAA to tyrosine ratio (BTR) is a surrogate marker (the normal range of BTR is between 4.41 and 10.05, and a Fischer's ratio of 1.8 corresponds to a BTR of 3.5) in patients with decompensated liver cirrhosis, and BCAA inhibits hepatic carcinogenesis in patients with compensated cirrhosis. This review discusses data regarding the effect of early administration of BCAA granules based on the ratio of BCAA to BTR on prognosis in patients with cirrhosis.

The use of feed-grade amino acids in lactating sow diets

Background: The use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics,increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of higher inclusion levels of feed-grade amino acid in lactation diets than previously published is warranted. Two experiments(Exp.) were conducted to determine the optimal inclusion level of L-lysine HCl to be included in swine lactation diets while digestible lysine levels remain constant across dietary treatments and allowing feed grade amino acids to be added to the diet to maintain dietary ratios relative to lysine to maximize litter growth rate and sow reproductive performance. Furthermore, the studies were to evaluate minimal amino acid ratios relative to lysine that allows for optimal litter growth rate and sow reproductive performance.Results: Exp. 1: Increasing L-lysine HCl resulted in similar gilt feed intake, litter, and reproductive performance.Average litter gain from birth to weaning was 2.51, 2.49, 2.59, 2.43, and 2.65 kg/d when gilts were fed 0.00, 0.075,0.150, 0.225, and 0.30% L-lysine HCl, respectively. Exp. 2: The average litter gain from birth to weaning was 2.68,2.73, 2.67, 2.70, and 2.64 kg/d(P < 0.70) when sows were fed 0.1, 0.2, 0.3, 0.4, and 0.4% L-lysine HCl plus valine,respectively. No other differences among dietary treatments were observed.Conclusions: Collectively, these studies demonstrate corn-soybean meal based lactation diets formulated with a constant SID lysine content for all parities containing up to 0.40% L-lysine HCl with only supplemental feed grade threonine and a methionine source have no detrimental effect on litter growth rate and subsequent total born.

Effect of Chelated Vanadium Spray on Concentration of Vanadium and Organic Compounds in Tea Shoots

The study aimed to develop vanadium tea products and evaluated the potential of chelated vanadium(V)absorption by tea shoots and effect of vanadium accumulation on tea quality during the first crop season.Chelated V application with three times foliar sprays at 5 days intervals starting from 15 days before plucking showed a significant increase in V content of new young shoots,which was much effective at higher concentration.However,one or two times sprays had no increase in V content regardless of spray concentration compared to non-treated.Despite V accumulation in the treated at 3 to 9 times higher that of than the non-treated plants,there were no significant changes in contents of total amino acids,theanine,caffeine,total polyphenols,crude fiber,and cathechins between the treated and the non-treated.

Analysis of amino acid enantiomers in ambient aerosols:Effects and removal of coexistent aerosol matrix

Amino acids(AAs)including D-and L-enantiomers are a group of organic nitrogen species in ambient aerosol.Due to the low abundances of AAs(level of ng/m^(3))and the matrix effects by coexistent components,it is challenging to quantify AA enantiomers in ambient aerosols especially under pollution conditions.In this study,we present an optimized method for analyzing AA enantiomers in atmospheric aerosol samples including a pretreatment process and the detection by high performance liquid chromatography coupled to a fuorescence detector(HPLC-FLD).Matrix effects caused by coexistent chemicals on AA enantiomers analysis in ambient aerosol samples were investigated especially for those collected in pollution episodes.The results revealed that the determination of AA enantiomers is significantly affected by the coexistent organic carbon(as a proxy of organic matter)and water-soluble ion of NH_(4)^(+).To remove the matrix effects,we applied a pretreatment using the solid phase extraction column coupled with alkaline adjustment to sample extract.After pretreatment,18 AAs including 6 pairs of D-and L-enantiomers(i.e.,leucine,isoleucine,valine,alanine,serine,and aspartic acid)can be successfully separated and quantified in aerosol samples by HPLC-FLD.The recoveries are in the range of 67%-106%.This method was successfully applied to the urban aerosol samples from pollution and non-pollution periods for AA enantiomers determination.We suggest that the concentrations of D-AAs and the ratio of D-AA/L-AA are indicative of the contribution of bacterial sources and the infuence of biomass burning.

An Elevated Dietary Cysteine to Methionine Ratio Does Not Impact on Dietary Methionine Efficiency and the Derived Optimal Methionine to Lysine Ratio in Diets for Meat Type Chicken

Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and female per dietary treatment) were utilized in N balance trials. During starter (d10 - 20) and grower period (d25 - 35) five dietary treatments were used. Diets based on uniform mixtures of maize, wheat, soybean meal, potato protein and fish meal were supplemented with crystalline amino acids (AA). In diets 1 - 3, the dietary Cys to Met ratio was set as 85, 95 and 105 to 100, respectively. Diet 4, at a Cys to Met ratio of 105 to 100, was additionally supplemented with betaine (BET) as methyl group donor. Diets 1 - 4 were limiting in Met, diet 5 without L-Lys·HCl addition was limiting in Lys. Individual N-balance data per treatment were utilized for assessing protein quality and efficiency of dietary Met (Diets 1 - 4) or Lys (Diet 5) based on “Goettingen approach”. Elevated dietary Cys supply and supplemented BET failed to improve both dietary protein quality and Met efficiency. The established optimal Met to Lys ratio was on average 34 to 100 for growing chicken during starter and grower period, respectively.

不同类型茄子果实主要营养成分和氨基酸含量分析

为了解茄子果实营养品质特性,对3种类型、15个茄子DH系的果实糖度、有机酸含量、可溶性糖含量、糖酸比、可溶性固形物含量、固酸比、游离氨基酸含量进行测定分析。结果表明,3种不同类型茄子的糖度和固酸比由高到低均为紫萼紫黑圆茄>紫萼紫黑长茄>绿萼紫黑长茄;有机酸含量为绿萼紫黑长茄>紫萼紫黑长茄>紫萼紫黑圆茄;葡萄糖、蔗糖含量均以绿萼紫黑长茄最高,果糖含量以紫萼紫黑圆茄最高;可溶性固形物含量以紫萼紫黑长茄最高;味感为鲜味、甜味的天冬氨酸、丝氨酸、甘氨酸含量由高到低均为紫萼紫黑圆茄>紫萼紫黑长茄>绿萼紫黑长茄,味感为酸甜味、苦味的天冬酰胺、精氨酸含量由高到低均为紫萼紫黑长茄>绿萼紫黑长茄>紫萼紫黑圆茄;紫萼紫黑长茄和绿萼紫黑长茄主要营养成分和游离氨基酸含量的变异度普遍高于紫萼紫黑圆茄。

新疆不同地区加工专用花生营养成分比较

花生生长条件和环境不同导致其品质出现差异,分析不同来源花生原料的品质有利于优化原料的选择,为花生产品加工利用提供参考。新疆南、北疆和东疆均有种植花生,但适合新疆不同地区种植的加工专用品种较少,采集新疆不同地区和内地3个省份的32个样品,对含油量、蛋白质、蔗糖、油酸/亚油酸(O/L)、蛋白亚基、氨基酸等6个指标进行测定、分析比较。结果表明,同一花生品种在不同地区种植后的营养成分含量存在一定差异,整体而言,新疆花生的含油量、蛋白质、蔗糖等指标在不同程度上优于内地,进一步分析得出花生在吐鲁番的含油量、O/L、伴花生球蛋白、总氨基酸含量最高,最高值为55.71%、35.11、37.39%、28.23 g/100 g,在阿拉尔的蛋白质、花生球蛋白含量最高,最高值为22.67 g/100 g、63.28%,在和田的蔗糖、23.5 ku亚基含量最高,为5.07 g/100 g、20.48%,在三坪的37.5 ku亚基含量最高(9.31%)。新疆不同地区不同品种花生的营养成分研究为新疆花生产业区域布局提供参考,为企业选择优质原料、建立原料基地提供依据。

桑枝栽培榆黄蘑子实体的氨基酸组成分析及蛋白质营养价值评价

对以桑枝栽培的榆黄蘑子实体中蛋白质、氨基酸含量及相关指标进行分析和评价,检测得到桑枝榆黄蘑子实体蛋白质含量为26.60 g·100^(-1)·g^(-1),属于高蛋白食品;含有18种氨基酸,种类齐全,较接近FAO/WHO模式的标准;支链氨基酸和芳香族氨基酸总量的比值为2.63;经氨基酸评分(amino acid score,AAS)、化学评分(chemical score,CS)、氨基酸比值系数评分(score of ratio coefficient of amino acid,SRCAA)3种指标评分,其第一限制氨基酸均为胱氨酸+蛋氨酸(Cys+Met);以FAO/WHO模式评价,桑枝榆黄蘑子实体所含蛋白质是优质蛋白,且营养价值较高。

High Fischer ratio oligopeptides in food:sources,functions and application prospects

High Fischer ratio oligopeptides(HFROs)are a group of oligopeptides containing high levels of branched-chain amino acids(BCAA)and low levels of aromatic amino acids(AAA).HFROs have received a lot of attention as they are believed to have significant physiological activities,including antioxidant,liver damage repair,anti-fatigue,anti-tumor and energy supply to the body.HFROs are available from a wide range of sources and both plant and animal proteins can be used to prepare HFROs but the physiological tolerability and rejection of special populations needs to be considered.Enzymatic hydrolysis is the most common method for the preparation of HFROs,but optimization of the separation and purification process is still needed in the future.Diseases caused by disruptions in the balance of BCAA and AAA in the blood,such as hepatic encephalopathy,can be treated by supplementing HFROs with drugs or food.In addition,HFROs are able to reduce fatigue feedback and assist in the treatment of phenylketonuria at the molecular nutrient level.The aim of this review is to review recent research on HFROs and provide new perspectives on the high value use of crops and the development of novel functional and special medical purpose foods.

3种萎凋环境对白茶含水量与生化成分含量的影响

目的探究3种萎凋环境对白茶含水量与生化成分含量的影响。方法以福鼎大白茶一芽二叶新稍为原料,采用传统室内自然萎凋、抽湿萎凋和空调萎凋3种萎凋方式,测定萎凋过程中茶叶含水量、茶多酚、游离氨基酸和黄酮类化合物含量。结果3种萎凋方式的茶叶含水量在萎凋24~32 h期间均迅速降低,尤其是抽湿萎凋,从44.11%降至16.03%;整体上茶多酚含量都是先升高后降低,整体变化范围小;与鲜叶对比,室内自然萎凋和抽湿萎凋中茶叶的黄酮类含量均显著增加,三者的游离氨基酸含量皆有显著增加,增幅为78.97%~110.3%;萎凋结束时,室内自然萎凋和抽湿萎凋的黄酮类与游离氨基酸含量皆显著高于空调萎凋。结论抽湿萎凋的茶叶在32h时水分含量基本达到萎凋叶标准,且氨基酸和黄酮类含量均在较高水平,说明抽湿萎凋具有成为效率与制优率兼备的潜能,本研究为提高白茶萎凋工效和毛茶制优率提供理论参考。

生物体中氨基酸单体碳稳定同位素测试方法研究

氨基酸作为蛋白质的基本组成单位,是重要的生命物质,其单体碳同位素研究在生物地球化学、生态学、生物体代谢和环境科学等领域具有重要意义。该文优化了海参和海藻氨基酸提取和纯化流程,通过N新戊酰基-O-异丙酯(NPP)方法衍生化后,分别用气相色谱-质谱(GC-MS)和气相色谱-燃烧-同位素比值质谱(GC-C-IRMS)测试其浓度和碳同位素组成。结果显示,15种氨基酸单体的分离效果较好,回收率为46.4%~96.3%,各氨基酸在1.0~16.0µmol/L范围内线性关系良好(r^(2)为0.987~0.999)。15种氨基酸单体衍生物δ^(13)C值的标准偏差均小于0.30‰(n=10),在0.6~2.0 mmol/L浓度范围内δ^(13)C的平均误差为±0.24‰,方法检出限为0.6 nmol。海参和海藻样品各氨基酸单体δ^(13)C值的范围分别为-31.10‰~-8.58‰和-30.53‰~-13.76‰,标准偏差均在0.33‰以内,可满足生物体氨基酸单体碳同位素的测试精度需求。

Imbalanced dietary methionine-to-sulfur amino acid ratio can affect amino acid profiles, antioxidant capacity, and intestinal morphology of piglets

Animal protein sources such as fishmeal and plasma powder are excellent and indispensable sources of energy,amino acid s,and minerals in animal production.Amino acid imbalance,especially methionine-to-sulfur amino acid(Met:SAA)ratio,caused by an imbalance of animal protein meal leads to growth restriction.This study was conducted to evaluate the effects of imbalanced Met:SAA ratio supplementation of different animal protein source diets on growth performance,plasma amino acid profiles,antioxidant capacity and intestinal morphology in a piglet model.Twenty-four weaned piglets(castrated males;BW=10.46±0.34 kg),assigned randomly into 3 groups(8 piglets/group),were fed for 28 d.Three experimental diets of equal energy and crude protein levels were as follows:1)a corn-soybean basal diet with a Met:SAA ratio at 0.51(BD);2)a plasma powder diet with a low Met:SAA ratio at 0.41(L-MR);3)a fishmeal diet with a high Met:SAA ratio at0.61(H-MR).Results revealed that compared to BD,L-MR significantly decreased(P<0.05)the activities of plasma total antioxidant capacity and glutathione peroxidase,plasma amino acid profiles,and significantly reduced(P<0.05)villus height and crypt depth in the duodenum and jejunum.Additionally,L-MR significantly reduced(P<0.05)the mRNA expression level of solute carrier family 7 member 9(SIC7 A9)in the ileum,and significantly increased(P<0.05)mRNA expression levels of zonula occludens-1(ZO-1)in the duodenum,and Claudin-1,ZO-1,sodium-coupled neutral amino acid transporters 2(SNAT2)and SIC7 A7 in the j ejunum.HMR significantly increased(P<0.05)plasma SAA levels,and significantly reduced(P<0.05)average daily feed intake,villus height,and villus height-to-crypt depth(VH:CD)ratio in the ileum compared to BD.In conclusion,L-MR may result in oxidative stress and villous atrophy but proves beneficial in improving intestinal barrier function and the activity of amino acid transporters for compensatory growth.H-MR may impair intestinal growth and development for weaned piglets.The research provides a guidance on the adequate Met:SAA ratio(0.51)supplementation in diet structure for weaned piglets.

Protein tolerance to standard and high protein meals in patients with liver cirrhosis

AIM To investigate the plasma amino acid response and tolerance to normal or high protein meals in patients with cirrhosis.METHODS The plasma amino acid response to a 20 g mixed protein meal was compared in 8 biopsy-proven compensated cirrhotic patients and 6 healthy subjects.In addition the response to a high protein meal(1 g/kg body weight) was studied in 6 decompensated biopsy-proven cirrhotics in order to evaluate their protein tolerance and the likelihood of developing hepatic encephalopathy(HE) following a porto-caval shunt procedure.To test for covert HE,the "number connection test"(NCT) was done on all patients,and an electroencephalogram was recorded in patients considered to be at Child-Pugh C stage.RESULTS The changes in plasma amino acids after a 20 g protein meal were similar in healthy subjects and in cirrhotics except for a significantly greater increase(P < 0.05) in isoleucine,leucine and tyrosine concentrations in the cirrhotics.The baseline branched chain amino acids/aromatic amino acids(BCAA/AAA) ratio was higher in the healthy persons and remained stable-but it decreased significantly after the meal in the cirrhotic group.After the high protein meal there was a marked increase in the levels of most amino acids,but only small changes occurred in the levels of taurine,citrulline,cysteine andhistidine.The BCAA/AAA ratio was significantly higher 180 and 240 min after the meal.Slightly elevated basal plasma ammonia levels showed no particular pattern.Overt HE was not observed in any patients.CONCLUSION Patients with stable liver disease tolerate natural mixed meals with a standard protein content.The response to a high protein meal in decompensated cirrhotics suggests accumulation of some amino acids but it did not precipitate HE.These results support current nutritional guidelines that recommend a protein intake of 1.2-1.5 g/kg body weight/day for patients with cirrhosis.

Using the RNA synthetic activity of glutamate dehydrogenase to illuminate the natural role of the enzyme

Glutamate Dehydrogenase (GDH;EC 1.4.1.2) catalyzes the reversible amination of α-ketoglutarate to glutamate, and the polymerization of nucleoside triphosphate(s) to RNA. But the natural role of the reversible amination reaction is the subject of an expanding conversation. The aim was to illuminate the natural role of GDH through its RNA synthetic activity. Stoichiometric combinations of mineral salts that targeted the GDH subunit compositions were applied to field-cultivated peanuts. GDH of seeds were made to synthesize RNA in the deamination and then in the amination direction. Free amino acids were analyzed by HPLC. Glutamate synthase (GOGAT) was assayed by photometry. Free amino acid yields in-creased from the control’s lowest (9.8 kg·ha–1) and amination-deamination ratio (0.05) through 12.0 - 23.0 kg·ha–1 in the K-, N+K+P+S-, Pi-, N+S-, S-treated peanuts with amination-deamination ratios between 0.6 and 10.0 until at the P+K-treated peanut which had the highest amino acid yield (52.4 kg·ha–1) and the highest amination-deamination ratio (61). The Km and Vmax values of GOGAT were within the normal range. Yields of free amino acids resulting from GDH aminating activity increased from <1.0 kg·ha–1 in the control, through 2.2 in the N+S-, 6.84 in the P+N-, 17.3 in the N-, to 42.6 kg·ha–1 in the P+K- treated peanut. These results show that the natural role of the GDH amination activity is to assimilate escalating multiples of the quantities of NH4+ ion as assimilated via the GS-GOGAT pathway. Peanut protein yields increased in parallel with GDH aminating activities and free amino acid yields such that the control peanut had the lowest protein (<26.0 kg·ha–1) and the yields increased exponentially (500 - 600 kg·ha–1) through the K-, P+S-, Pi-, N-treated to 910 kg·ha–1 in the P+K-treated peanut with the highest aminating activity of GDH. The ability of GDH aminating activity to escalate protein yields of food crops could be employed to address proteinenergy malnutrition syndrome of developing nations.

Variation for Health-Enhancing Compounds and Traits in Onion (Allium cepa L.) Germplasm

Consumption of onion has been associated with reduced incidence of chronic diseases. Phenolic, organosulfur and carbohydrate compounds present are largely responsible for these effects. This study examined compositional variation for health-enhancing compounds in a genetically diverse collection of onion cultivars. Total antioxidant activity and aroma profiles were characterized. Significant variation in bulb concentration for total and individual phenolic compounds, thiosulfinates, carbohydrates, and total and soluble solids was found. The range of variation was particularly large (>50-fold difference between the cultivars with the highest and lowest content) for fructo-oligosaccharides (FOS) and the polyphenols quercetin, epigallocatechin gallate and epicatechin gallate. Amino acid profiles varied significantly as well with substantial variation (~10 fold) observed in both total and essential amino acids. Total antioxidant activity was positively correlated with polyphenols content, and quercetin in particular (r = 0.83), suggesting a major contribution from phenolic compounds to onion antioxidant properties. Significant positive correlation was also found between solids and thiosulfinates content (r = 0.74) and between solids and FOS (r = 0.81), suggesting a dilution/concentration effect for organosulfur compounds and FOS in onion bulbs. The present study revealed broad variation for health-enhancing compounds content in onion germplasm, which can be exploited in breeding programs aiming at increasing onion nutraceutical value.

龟甲炮制工艺研究

目的:探索龟甲最优炮制工艺。方法:以18种氨基酸总含量和总多酚含量为评价指标,采用L_(9)(3^(4))正交试验优化转速、砂烫温度、砂烫时间,并进行验证实验。结果:在转速为20 r·min^(-1)、砂烫温度为240℃、砂烫时间为2 min条件下炮制龟甲,炮制品质地酥脆、总氨基酸和总多酚溶出度较高,3批炮制品的氨基酸平均总质量分数和总多酚平均质量分数分别为19.67%、50.74 mg·kg^(-1)(RSD分别为1.06%、0.87%)。结论:优化的龟甲炮制工艺稳定可行,可为龟甲工业化生产工艺研究提供参考。

市售冷泡绿茶主要品质成分冷泡浸出规律研究

“冷泡茶”(Cold-brewing tea)因其最大程度保留了茶叶的鲜爽味且兼具饮用便利性,已成为消费者追捧的新型茶饮。文章系统研究了7个市售冷泡绿茶以及1个自制冷泡龙井茶的主要品质成分及其冷水浸出规律。结果表明,冷泡茶的含水率在4.12%~12.95%之间,差异较大;水浸出物、茶多酚、游离氨基酸和咖啡碱含量范围分别在34.06%~45.32%、23.99%~32.04%、3.03%~4.22%和2.78%~3.21%。随着冷水浸泡时间延长,茶汤中主要品质成分含量均逐渐增加。冷水浸泡40 min,所有样品的茶汤中水浸出物溶出率为19.7%~51.4%、茶多酚溶出率5.3%~19.0%、氨基酸溶出率24.4%~93.1%、咖啡碱溶出率在18.4%~39.3%。冲泡方式显著影响茶叶中茶多酚、氨基酸和咖啡碱的溶出率,冲泡20 min后茶多酚冷/热水溶出比为0.30~0.60、咖啡碱冷/热水溶出比为0.18~0.34、游离氨基酸冷/热水溶出比超过0.70,冷水浸泡茶汤中游离氨基酸溶出率较茶多酚和咖啡碱高,是冷泡绿茶口感更加鲜爽的主要原因。本研究结果可为冷泡茶产品质量标准制定和新型冷泡茶产品开发提供理论依据。

树皮内含物对星天牛寄主选择的影响

为明确不同寄主树皮内含物与星天牛寄主选择的关系,探寻星天牛寄主选择机制,在室内水培环境下,进行星天牛对8种寄主取食、栖息和产卵选择试验,观察星天牛在各寄主上的取食面积、取食痕迹数量、栖息和产卵数量,并对寄主树皮内含物含量进行测定。结果表明:星天牛偏向于取食红枫、复叶槭和糖槭,喜好在复叶槭、糖槭和苦楝上栖息、产卵,极少在纳塔栎和垂柳上取食、栖息和产卵。相关性分析结果表明:星天牛取食面积、栖息数量、产卵数量与寄主树皮内氨基酸总含量、氨基酸含量呈显著正相关,与碳氮比呈显著负相关,与可溶性总糖、可溶性蛋白、单宁、总酚含量无显著相关。星天牛取食痕迹数量与本次试验所测的寄主内含物含量无显著相关。寄主树皮的碳氮比、氨基酸含量是影响星天牛取食、栖息和产卵选择的重要因子,适宜的碳氮比、较高的氨基酸含量是星天牛寄主选择的标准。