Journal of Northeast Agricultural UniversityEnglish Edition最新文献

Abstract

We cloned and expressed bile salt hydrolase gene of Lactobacillus plantarum M1-UVS29 in Lactococcus lactis NZ9000 successfully. Gene-specific primers for amplification of L. plantarum bsh were designed by using sequence which availabled from GenBank. The production of PCR amplicon was confirmed by sequencing and cloned into pMD18-T vector, and then recombined into expression vector pNZ8148 and yielding vector pNZ8148-BSH. pNZ8148-BSH was transferred into Lactococcus lactis NZ9000. Sequencing indicated that the cloned bsh fragment contained 995 nucleotides, and shared 99.3% sequence homology with bsh gene from L. plantarum MBUL10. Cloned bsh fragment was successfully transduced into NICE expression system and confirmed by PCR and restriction digest. Recombinant BSH protein was analyzed by SDS-PAGE. The molecular weight of BSH protein was approximately 37 ku. Activity of the expressed protein was 0.77 μmol • min⁻¹. The successfully expressed proteins by genetic engineering technology made the function of lactic acid bacteria be abundant and laid the foundation for further researches into cholesterol-lowering lactic acid bacterium food and probiotics.

Abstract

This study was conducted to analyze the factors that negatively influence Pakistani farmers' willingness to participate in crop insurance. Probit model was applied to identify the significant factors which influenced our dependent variable “not willing to participate”. The results of the analyses showed that crop insurance premium was the most influencing factor which had positive and significant impact on dependent variable. Similarly dissatisfaction with crop loan insurance scheme, lacking of knowledge about crop insurance, believing of being against Islamic rules and time taking process was also found to be positive and significantly influenced the dependent variable. While limited decision power and limited perils were not found to be significant in the results.

Abstract

Methionine and lysine are restrictive essential amino acids of livestock, they are also the most attentive indexes in the feed production to carry out the quality control and quality evaluation. Their contents in feed directly affect livestock protein synthesis. Bacillus natto has excellent probiotic properties. In this experiment, we used the genetic engineering method, fusion PCR technique, to connect methionine-rich gene (zein) from maize endosperm protein with lysine-rich gene (Cflr) from the pepper anther, then the fusion gene was inserted into the expression vector pHT43, and the recombinant plasmid pHT43/zein-Cflr was constructed. The recombinant plasmid was transferred into Bacillus natto, and induced by IPTG for the expression of the fusion gene. We found an apparent band at 40 ku site for the recombinant strain by SDS-PAGE. The contents of methionine and lysine were individually detected with HPLC, the quantities of methionine and lysine in the recombinant strain increased by 18.37% and 24.68% than the wild one, respectively. We also verified the stability of the recombinant bacterium during passaging, and found the stability was 100%. This study provided research-basis for the application of the recombined Bacillus natto as feed additive.

With the gradual acceleration of urbanization speed and continuous improvements of agricultural productivity, the number of migrant workers is increasing. The living conditions of this group in cities determine the quality of urbanization in China, and are of great and far-reaching significance to Chinese construction of comprehensive well-off society. This study took the migrant workers in Heilongjiang Province as the research object, and took the representative new-generation migrant workers as the respondent to have a comprehensive analysis of the employment status. The study focused on these aspects, such as nature information, employment selection, employment quality, and social security, etc. Finally, it provided valuable ideas and methods on the reasonable solutions of the employment problems of the migrant workers to better increase farmers’ income and improve their living qualities.

The antioxidant activities and the total phenolic contents of the water and/or ethanol extracts of the nine selected culinary spices from China were systematically investigated. Both ethanol extracts and water extracts had high ability of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 2, 2'-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging and ferric reducing antioxidant power (FRAP). The ethanol extract of Sichuan pepper showed the highest ability of DPPH radical scavenging. The extract with the highest ABTS radical scavenging effect was that of ethanol extract of cinnamon. Both ethanol and water extracts of cinnamon possessed the high ferric reducing antioxidant power (FRAP) with the values of 4 541.87 and 1 134.52 µmol of Fe (II)/g. The extracts with high hydroxyl radical-mediated deoxyribose degradation were all the ethanol extracts as follows: cinnamon, bay leaf, Sichuan pepper, star anise and fennel. The extracts with high antioxidant activities also had the high contents of the phenols. The study indicated that these spices might be potentially be used as natural antioxidants in food.

At present, the excessive use of the fertilizers and pesticides in the agricultural production has result in hardening of the soil and decrease of the wild animals and can not maintain the sustainable using of land resources. To develop ecological agriculture is a powerful measure to reduce energy consumption, protect environment, and realize the sustainable development of the agriculture. In order to promote the sustainable development of agriculture in Jianshan Farm, this paper by using SWOT analysis method analyzed the strength, weakness, opportunity and threat in the development of the ecological agriculture in Jianshan Farm, based on the experience from domestic and foreign ecological agricultural development, and put forward the countermeasures for the development of the ecological agriculture in order to develop ecological circular agriculture and non-genetic soybean crop protected areas, and to establish soybean-corn rotation area and healthy aquaculture zone, as well as develop new energy industry.

MicroRNA (miRNA) is a class of important regulating non-coding small molecular RNA. The gma-MIR166 gene family consists of 21 members and their expression patterns diversify widely. It is important to analyze the evolution of gma-MIR166 gene family in order to understand the evolutionary mechanisms of miRNAs in soybean. In this study, we implemented soybean wide genome block analysis, the molecular phylogeny of gma-MIR166 and block analysis of gma-MIR166 family. The results showed that both chromosome big segmental duplications and tandem duplications were main reasons contributed to the expanding of gma-MIR166 gene family. These findings suggested that gma-MIR166 gene family might originate from one or two ancient miRNA genes. The results of research provided a support for evolutionary study of miRNAs in soybean and related species in Fabaceae.

The forest ecological compensation is an important factor to balance the interests of different areas for sustainable development and environment protection. Mudanjiang City in Heilongjiang Province of China is rich of forest resources. The forestry coverage rate reached 62.3% in 2014, after forestry conservation program from 2002. The authors explored the factors impacted on forest ecological compensation in Mudanjiang City, which was a demonstration as a case study, through experts’ evaluation scores and AHP methodology to analyze the forest ecological compensation factors and lay the foundation for the establishment of ecological compensation mechanism. At the same time, we provided an example to explore the effective way and speed up the establishment of ecological compensation mechanism. The study found that the main factors that determined forest ecological compensation in Mudanjiang City were ecology and natural resources. Based on the analyses, some suggestions were put forward to promote the mechanism in a sustainable way.

Subclinical endometritis is a physiological inflammation that serves to clear persistent contaminants from the uterus. To investigate the alteration of antioxidant, such as vitamin E (VE) and vitamin C (VC), total oxidant capacity (TOC) and nitric oxide (NO) in cows with normal and subclinical endometritis (SCE), we examined the concentrations of NO, VC and VE, TOC and polymorphonuclear neutrophils (PMN) percentage in uterine secretion. The cows were divided into two groups, normal (n=20) and subclinical endometritis (SCE, n=60), based on endometrial cytology (presence of PMN±5%). Uterine secretion and blood were collected as described previously. Griess reaction was used to determine the concentration of NO. The concentrations of TOC, VC and VE were detected by a commercially available assay kit. The results showed that the concentrations of NO, TOC and PMN percentage were significantly higher (P<0.01, P<0.05, and P<0.01, respectively) in uterine secretion with SCE compared to those from normal; however, the levels of VC and VE were significantly lesser (P<0.01). In conclusion, the concentrations of NO, TOC, VC, VE and PMN percentage differed between normal and SCE cows. Meanwhile, the relationship between the concentration of NO and PMN percentage from uterine secretion in cows with subclinical endometritis were positively correlated. Consequently, these alterations in NO, TOC, VC, VE levels and PMN percentage contributed to as a diagnostic index of the uterine inflammation, with the aim to increase the reproduction of the cows and the decrease economic losses.

In recent years, the great achievements of basic medical and healthcare services of BRICS have gained great attention and acknowledgement from the whole world. In their medical system reform, India, Brazil, Russia and South Africa have established their medical systems with their own characteristics. This provides valuable references for China in its critical stage of medical system reform. This paper explored the experience of BRICS’ reform of medical system in order to offer some references and guidance for the establishment of basic medical and health services with Chinese characteristics and conforming to Chinese practice.