Localization of amino acids in germinated rice grain: Gamma-aminobutyric acid and essential amino acids production approach

Germinated rice is popularly consumed for its high gamma-aminobutyric acid (GABA) and bioactive compounds. Supporting information on how to germinate rice with high GABA content and essential amino acids is lacking. White and colored rough rice were germinated for 0, 24, 48, 72, 96, 120 and 144 h. GABA, GABA substrates and essential amino acids were also investigated using GC-MS and MALDI-MSI. GABA was more concentrated after germination and shifted into the coleoptile. High correlation was recorded between germination time and GABA (0.79–0.83, p ≤ 0.01) and glutamic acid (0.88–0.89, p ≤ 0.01). Highest rates of GABA and glutamic production were observed within 48 h of germination in both rice varieties (26.12 and 34.28 mg/100g) and reached maximum value at 96 h (31.36 and 38.75 mg/100g). Colored rice germination showed higher GABA, GABA substrates and deficient amino acids than white rice. GABA and essential amino acids drastically increased after germination, supporting the consumption of germinated rice as a functional food.     

Using vibrational molecular spectroscopy to detect moist heating induced carbohydrates structure changes in cool-climate adapted barley grain

There is limited research to study how moist heating affects internal structure of barley grain on a molecular basis. The objectives of this study were to use vibrational molecular spectroscopy: 1) to determine the moist heating induced changes of barley carbohydrate (CHO) structure on a molecular basis, 2) to study the effects of moist heating on CHO chemical profiles, Cornell Net Carbohydrate and Protein System (CNCPS) subfractions, in situ rumen degradation, and predicted intestinal carbohydrate supply of barley grain; and 3) to reveal the association between molecular structure spectral features and CHO related metabolic characteristics. Barley samples (CDC cowboy) were collected from Kernen Crop Research Farm (Saskatoon, Canada) during two consecutive years. Half of each sample was kept as raw barley and the other half underwent moist heating (autoclaving at 120 °C for 60 min). The molecular spectroscopy (attenuated total reflectance-fourier transform infrared, ATR-FTIR) was used to detect the barley CHO related molecular structure spectral features. Moist heating did not affect carbohydrate related chemical profiles and CNCPS subfractions but it decreased rumen degradable carbohydrate. Rumen undegradable and intestinal digestion of CHO subfractions were not affected by moist heating. The advanced vibrational molecular spectroscopy can be used to detect carbohydrate molecular spectral features. Nutrient utilization prediction using molecular spectral characteristics is warranted and further investigation is encouraged.     

Impact of ethanol,succinic acid,and the combination thereof at levels produced during sponge fermentation on hard wheat,soft wheat,and durum wheat farinograph rheology

The sponge and dough mixing process is one of the most common in the world, yet the mechanistic understanding of this process has yet to be sufficiently explored. In this study, aqueous solutions of ethanol, succinic acid, and their combination were prepared at concentrations intended to replicate fermentation times of 3, 4 and 6 h. These solutions were added to a farinograph mixer to make dough using hard wheat, soft wheat, and durum wheat flour. The results indicate that these yeast metabolites (ethanol, succinic acid) impact the mixing resistance, peak mixing value, and dough mixing stability in each of the flour types, likely primarily affected by the ratios of gliadin to glutenin and LMW glutenin in each flour type. Results suggest a stabilizing non-covalent interaction imparted by gliadin at peak mixing time, a stabilizing effect of HMW glutenin during break down, and synergistic effects of ethanol and succinic acid that leads to a faster rate of breakdown in later stages of mixing. It also suggests an increase in mixing resistance when acidulants are added to durum wheat dough. Taken together, this study adds new insights on the sponge and dough mixing process in a way that has not previously been conducted.     

Characterization and bioactivities of young rice protein hydrolysates

Immature rice was reported to contain higher quantities of bioactive compounds than mature rice. Young rice protein is easy to digest and has hypoallergenic potential, with protein content of 7.2–11.5% compared to rice bran at 9.8%. Few studies have reported on bioactivities and characterization of young rice proteins and their hydrolysates. Bioactivities of native protein and protein hydrolysates of two rice varieties (white rice and colored rice) were characterized and investigated for four development stages (flowery, milky, dough, and mature). Degree of hydrolysis of young rice protein was considerably higher than at the mature stage. Highest DPPH and iron chelating activity were found in alcalase® protein hydrolysate during the flowery-to-milky stage. Iron chelating activity was constant in all development stages because of the low polar amino acid content in rice. The ACE activity of alcalase® protein hydrolysate was higher than native protein at the same development stage, as observed in the milky and dough stages. Inhibitory activity of young rice hydrolysate HepG2 cells was concentration-dependent and not correlated with protein molecular size.     

胡椒4-香豆酸：辅酶A连接酶Pn4CL基因的克隆及表达分析

根据胡椒4-香豆酸：辅酶A连接酶（4-coumarate:coenzyme A ligase, 4CL）基因的部分序列设计引物,运用RACE方法获得其家族成员的1个全长cDNA,命名为Pn4cl,长度2130 bp,开放阅读框1638 bp,编码545个氨基酸。预测Pn4CL分子量为59.57 kDa,理论等电点为5.70。该基因含有AMP-binding（AMP-binding enzyme）、CaiC[Acyl-CoA synthetase (AMP-forming) /AMP-acid ligaseⅡ]、PLN02246、AFD-class I等结合域,具有植物4CL所共有的保守结构域。系统进化分析表明,Pn4CL与北细辛的同源性最高,同时与木兰分支类植物的4CL聚类在一起,与菊分支的进化距离较近,与蔷薇分支的进化距离较远。亚细胞定位表明,该蛋白定位在细胞膜上。Real-time RT-PCR结果表明,该基因受外援激素SA和MeJA诱导表达,同时接种辣椒疫霉菌后,Pn4CL基因的表达量在抗/感2种胡椒中均出现先增加后减少的现象,并且在抗病种质中表达量较高。研究结果为Pn4CL的功能研究提供了理论依据。     

Analysis of sinking death using video images of the swimming performance of Pacific Bluefin tuna (Thunnus orientalis) larvae

In this study, we aimed to clarify the mechanism of sinking death during the larval stage of Pacific Bluefin tuna Thunnus orientalis by investigating the effects of swimming performance on sinking death, using a behavioral approach. Swimming performance was examined 3–9 days after hatching (DAH) under day and night light conditions in cuboid experimental tanks. Swimming behavior variables such as swimming speed and swimming angle were measured under both light conditions. Larvae in the daytime experiment and larvae with inflated swim bladders at night were distributed on the surface layer of the water column. In contrast, larvae with uninflated swim bladders at night were frequently observed swimming vertically or sinking to the bottom of the tank. Larvae with inflated swim bladders at night were always distributed beneath the surface until the next morning (survival rates were 100 %). However, larvae with uninflated swim bladders at night swam upward repeatedly and later sank to the bottom of the tank (survival rates were 60 % and 38 % at 5 and 9 DAH, respectively). Larvae with uninflated swim bladders were not always able to maintain their swimming depth by swimming until the next morning. Additionally, their swimming speed and vertical swimming frequency (ratio) depended on the illumination and swim bladder conditions. Our findings show that larvae with uninflated swim bladders at night were associated with a higher risk of sinking death. The swimming energy capacity of Pacific Bluefin tuna larvae, which indicates the total amount of the energy that enables individuals to swim throughout the night without feeding, was found to be linked to sinking death.     

韭菜生产中施肥量、播量与产量的相关关系张桂海 王明耀 王学颖 黄志辉 王长浩 田庆武 张钊

通过播种量与施肥量的组合试验,寻求韭菜合理的播种量的区间与最佳的施肥量,得到韭菜生产种子的播量范围为2.38kg /667㎡～3.00kg/667㎡。     

智慧农业背景下大数据与农民增收之间的关系

自信息化时代以来，大数据时代是继物联网、云计算的又一次技术变革，这次变革加速了传统农业向数字农业、信息农业的转变。智慧农业的发展，创造了多维的与农业有关的数据。阐述了在农产品种植前的规划、种植时的管理和收获之后的营销，在已有的数据中挖掘可用的信息，农民可以准确掌握市场供需情况，合理安排种植，做到精准农业，帮助农民提升收入。     

Development of a reverse-transcription loop-mediated isothermal amplification assay to detect avian influenza viruses in clinical specimens

In recent years, the avian influenza has brought not only serious economic loss to the poultry industry in China but also a serious threat to human health because of the avian influenza virus(AIV) gene recombination and reassortment. Until now, traditional RT-PCR, fluorescence RT-PCR and virus isolation identification have been developed and utilized to detect AIV, but these methods require high-level instruments and experimental conditions, not suitable for the rapid detection in field and farms. In order to develop a rapid, sensitive and practical method to detect and identify AIV subtypes, 4 specific primers to the conserved region of AIV M gene were designed and a loop-mediated isothermal amplification(RT-LAMP) method was established. Using this method, the M gene of H1–H16 subtypes of AIV were amplified in 30 min with a water bath and all 16 H subtypes of AIV were able to be visually identified in presence of fluorescein, without cross reaction with other susceptible avian viruses. In addition, the detection limit of the common H1, H5, H7, and H9 AIV subtypes with the RT-LAMP method was 0.1 PFU(plaque-forming unit), which was 10 times more sensitive than that using the routine RT-PCR. Further comparative tests found that the positivity rate of RT-LAMP on detecting clinical samples was 4.18%(14/335) comparing with 3.58%(12/335) from real-time RT-PCR. All these results suggested that the RT-LAMP method can specifically detect and identify AIV with high sensitivity and can be considered as a fast, convenient and practical method for the clinic test and epidemiological investigation of AIV.     

液相色谱柱后衍生法快速测定马铃薯中10种氨基甲酸酯类农药残留

为了提高马铃薯氨基甲酸酯类农药残留检测效率，采用高效液相色谱柱后衍生法建立了马铃薯中10种氨基甲酸酯类农药的快速检测方法，并采用加标回收的方法测定回收率和精密度，以检验该方法的准确性和可靠性。结果表明：10种氨基甲酸酯农药回收率为77.1%～106.0%，相对标准偏差（RSDs） 为1.2%～6.7%，说明液相色谱柱后衍生法快速测定方法简单、快速、经济，可满足马铃薯中10种氨基甲酸酯类农药残留的检测工作。