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    2011 Vol. 10 No. 6    Next Issue

    Original Articles

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    Original Articles
    Cloning One CIPK Gene from a Thermo-Sensitive Genic Self-Incompatible Line in Maize Expressing Under Different Temperatures
    LIN Xing-e, JI Hong-qing, NIU Jun-hai, HU Yan-min, FU Zhong-jun, LIU Zong-hua, TANG Ji-hua
    2011, 10(6): 813-819.  DOI: 10.1016/S1671-2927(11)60066-7
    Abstract ( )   PDF in ScienceDirect  
    A calcineurin B-like protein-interacting protein kinases (CIPK) gene was cloned (EU 424058) from a thermo-sensitive genic self-incompatibility (TSGI) line, HE97, in maize, which was selected for suppression subtractive hybridization (SSH) library of the self-incompatible and self-compatible silks of the TSGI line under different temperatures. The full-length cDNA of the candidate CIPK-like gene consisted of 1 918 nucleotides and contained a 1 332-bp open reading frame in maize. Real-time PCR indicated that the candidate CIPK-like gene was highly expressed in the self-incompatible pollen of the TGSI line, and promoted elevated levels of calcium (Ca2+). High Ca2+ concentrations in the pollen strongly inhibit pollen tube formation in silk of the same plant, thus inducing self-incompatibility (SI) under high temperature. These results implied that the CIPKs-like gene would play an important role in the regulation of HE97 characteristics under different temperatures, perhaps acting as a secondary messenger in the expression of SI in the TGSI line in maize.
    Transient Expression of Exogenous Gene into Plant Cell Mediated by PEI Nanovector
    LI Ying, CUI Hai-xin, SONG Yu, LI Yao, HUANG Jin-li
    2011, 10(6): 820-826.  DOI: 10.1016/S1671-2927(11)60067-9
    Abstract ( )   PDF in ScienceDirect  
    This study was carried out to investigate the transfection effect of exogenous gene into plant protoplast cell mediated by polyethylenimine (PEI) nanovector, based on PEI gene delivery system in the field of medical science. PEI/DNA complexes were prepared by using PEI polymer to bind the plant expression plasmid, pCMl205-GFPn. The ability of PEI combining and protecting DNA was investigated by agarose gel electrophoresis retardation assay. The surface characteristics of PEI/DNA complexes were observed with transmission electron microscope. The transfection efficiency of Arabidopsis thaliana protoplasts mediated by PEI/DNA complexes at different N/P ratios was analyzed based on observation of transient expression of green fluorescent protein with confocal laser scanning microscope. PEI could bind and condense DNA, and form stable 100-200 nm PEI/DNA complexes when the proportion of PEl and DNA is in the range of 5:1-1:4. Transfection efficiency of PEI/DNA complexes increased with N/P ratios in range of N/P<5 and reached the highest at N/P=5, and began to decrease beyond N/P>5 as higher toxicity to cells. The transfection efficiency of PEI/DNA complexes at N/P=5 was higher than PEG. This study confirmed that PEI nanovector could effectively mediate foreign gene entering into A. thaliana protoplast cell to obtain transient expression, which may be developed as a hopeful and novel transgenic method combined with plant protoplast regeneration.
    Natural Variation of Pto and Fen Genes and Marker-Assisted Selection for Resistance to Bacterial Speck in Tomato
    SUN Wan-yu, ZHAO Wan-ying, WANG Yuan-yuan, PEI Cheng-cheng and YANG Wen-cai
    2011, 10(6): 827-837.  DOI: 10.1016/S1671-2927(11)60068-0
    Abstract ( )   PDF in ScienceDirect  
    The resistance in tomato plants to bacterial speck caused by Pseudomonas syringae pv. tomato is triggered by the interactions between the plant resistance protein Pto and the pathogen avirulence proteins AvrPto or AvrPtoB. Fen is a gene encoding closely related functional protein kinases as the Pto gene. To investigate the status of resistance to the pathogen and natural variation of Pto and Fen genes in tomato, 67 lines including 29 growing in China were subject to disease resistance evaluation and fenthion-sensitivity test. Alleles of Pto and Fen were amplified from genomic DNA of 25 tomato lines using polymerase chain reaction (PCR) and sequences were determined by sequencing the PCR products. The results indicated that none of the 29 cultivars/hybrids growing in China were resistant to bacterial speck race 0 strain DC3000. Seven of eight tomato lines resistant to DC3000 were also fenthion-sensitive. Analysis of deduced amino acid sequences identified three novel residue substitutions between Pto and pto, and one new substitution identified between Fen and fen. A PCR-based marker was developed and successfully used to select plants with resistance to DC3000.
    Original Articles
    Genetic Diversity Analysis of Faba Bean (Vicia faba L.) Based on EST-SSR Markers
    GONG Ya-ming, XU Sheng-chun, MAO Wei-hua, LI Ze-yun, HU Qi-zan, ZHANG Gu-wen and DING Ju
    2011, 10(6): 838-844.  DOI: 10.1016/S1671-2927(11)60069-2
    Abstract ( )   PDF in ScienceDirect  
    Faba bean (Vicia faba L.), one of the most important legumes in the world, evolved different types of cultivars due to its partial cross-pollination. The development of simple sequence repeat (SSR) markers from expressed sequence tags (EST) provided a useful tool for investigation of its genetic diversity. The purpose of the present study was to investigate the genetic diversity of faba bean from China and Europe using EST-SSR markers. 5 031 faba bean ESTs from the NCBI database were downloaded and assembled into 1 148 unigenes. A total of 107 microsatellites in 96 unigenes were identified, indicating that merely 8.36% of sequences contained SSRs. The most abundant SSR within faba bean was tri-nucleotide repeat motif, and among all the tri-nucleotide repeats, the motif AAG/CTT was the most abundant type. Based on these results, 11 EST-SSR markers were used to assess the genetic diversity of 29 faba bean cultivars from China and Europe with two to three alleles per locus. The polymorphism information content value ranged from 0.0644 to 0.4278 with an average of 0.2919. Principal coordinate analysis (PCA) and phylogenetic clustering based on these 11 EST-SSR markers distinguished these cultivars into different groups. The results indicated that faba bean in China had a narrow genetic basis, and the additional sources of genetic cultivars/accessions should be introduced to enhance the genetic variability. The results of this study proved that the EST-SSR marker is very effective in evaluation of faba bean germplasm.
    Actin and Myosin Co-Localize in Plasmodesmata and Ectodesmata-Like Structure
    DONG Yu, LIU Na, LIU Gang, LI Wen-long, YAN Ai-hua and WANG Dong-mei
    2011, 10(6): 845-849.  DOI: 10.1016/S1671-2927(11)60070-9
    Abstract ( )   PDF in ScienceDirect  
    Actin and myosin were found to be associated with the cytoplasmic sleeve of plasmodesmata. As cytoskeletal proteins, actin and myosin are believed to regulate the conductivity of plasmodesmata (PDs) in higher plants. Using immunocytochemical methods, we found the two proteins to be co-localized - and closely linked to each other - in plasmodesmata and ectodesmata-like structure in ageing parenchymatous cells of Allium sativum L. We suggest that intercellular communication is affected by the interaction between actin and myosin.
    Benefits of Conservation Agriculture on Soil and Water Conservation and Its Progress in China
    LI Ling-ling, HUANG Gao-bao, ZHANG Ren-zhi, Bill Bellotti, Guangdi Li and Kwong Yin Chan
    2011, 10(6): 850-859.  DOI: 10.1016/S1671-2927(11)60071-0
    Abstract ( )   PDF in ScienceDirect  
    Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture (CA) is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement, and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world’s arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture.
    Effects of Conservation Tillage on Crop Yield: a Case Study in the Part of Typical Ecological Zones in China
    TANG Qiu-xiang, LI Shao-kun, XIE Rui-zhi, ZHANG Jian-xin, REN Tian-zhi, LIN Tao and GAO Shi-ju
    2011, 10(6): 860-866.  DOI: 10.1016/S1671-2927(11)60072-2
    Abstract ( )   PDF in ScienceDirect  
    To evaluate the effects of different conservation tillage modes on crop yield in various ecological regions, we interviewed peasant households in the Northeast China Plain, North China Plain, Chengdu Plain, and Northwest China Oasis, China,to analyze the influencing factors of the tillage methods on crop yield. An index set was determined from seven yield parameters based on expert consultation and relevant literature. A comprehensive evaluation of conservation tillage methods in the various ecological regions was carried out using fuzzy theory. The approaches with the highest scores were identified for each region: wide and narrow rotation planting with high stubble standing retention in the Northeast China Plain; seeding after rotary tilled of wheat under corn straw mulching and no-tillage seeding of corn and other crops under wheat straw mulching in the North China Plain; no tillage with high stubble retention in the Northwest China Oasis;and no-tillage seeding of wheat and other crops under rice straw mulching in Chengdu Plain. These research data provide a useful guide for the selection of conservation tillage methods for optimum yields in different regions of China.
    Thrips: Pests of Concern to China and the United States
    Stuart R Reitz, GAO Yu-lin and LEI Zhong-ren
    2011, 10(6): 867-892.  DOI: 10.1016/S1671-2927(11)60073-4
    Abstract ( )   PDF in ScienceDirect  
    Thrips are among the most important agricultural pests globally because of the damage inflicted by their oviposition,feeding, and ability to transmit plant viruses. Because of their invasiveness, a number of pest species are common to both China and the United States and present significant challenges to growers of a wide range of crops in both countries. Among the pest thrips common to both countries are four of the major global thrips pests, Frankliniella occidentalis (Pergande), Scirtothrips dorsalis Hood, Thrips palmi Karny, and Thrips tabaci Lindeman. This review addresses characteristics that enable thrips to be such damaging pests and how biological attributes of thrips create challenges for their management. Despite these challenges, a number of successful management tactics have been developed for various cropping systems. We discuss some of these tactics that have been developed,including the use of cultural controls, biological controls, and judicious use of insecticides that do not disrupt overall pest management programs. The exchange of this type of information will help to facilitate management of pest thrips, especially in regions where species have recently invaded. A prime example is F. occidentalis, the western flower thrips, which is native to the United States, but has recently invaded China. Therefore, management tactics developed in the United States can be adapted to China. Because further success in management of thrips requires a thorough understanding of thrips ecology, we discuss areas of future research and emphasize the importance of collaboration among different countries to enhance our overall understanding of the biology and ecology of thrips and to improve management programs for these widespread pests.
    Isolation and Expression Patterns of Rice WRKY82 Transcription Factor Gene Responsive to Both Biotic and Abiotic Stresses
    PENG Xi-xu, TANG Xin-ke, ZHOU Ping-lan, HU Yao-jun, DENG Xiao-bo, HE Yan and WANG Hai-hua
    2011, 10(6): 893-901.  DOI: 10.1016/S1671-2927(11)60074-6
    Abstract ( )   PDF in ScienceDirect  
    WRKY transcription factors are involved in the regulation of response to biotic and abiotic stresses in plants. A fulllength cDNA clone of rice WRKY82 gene (OsWRKY82) was isolated from a cDNA library generated from leaves infected by Magnaporthe grisea. OsWRKY82 contained an entire open reading frame in length of 1 701 bp, and was predicted to encode a polypeptide of 566 amino acid residues consisting of two WRKY domains, each with a zinc finger motif of C2H2,belonging to the WRKY subgroup I. OsWRKY82 shared high identity at the amino acid level with those from Sorghum bicolor, Hordeum vulgare, and Zea mays. The transcript level of OsWRKY82 was relatively higher in stems, leaves, and flowers, and less abundant in grains. It was induced by inoculation with M. grisea and Rhizoctonia solani. However, the inducible expression in incompatible rice-M. grisea interactions was earlier and greater than that in compatible interactions.The expression of OsWRKY82 was up-regulated by methyl jasmonate and ethephon, whereas salicylic acid exerted no effects on its expression. Moreover, OsWRKY82 exhibited transcriptional activation ability in yeast. Additionally,OsWRKY82 transcripts could be induced by wounding and heat shocking, but not by abscisic acid, cold, high salinity and dehydration. By contrast, gibberellin suppressed the expression of OsWRKY82. These indicate that OsWRKY82 is a multiply stress-inducible gene responding to both biotic and abiotic stresses, and may be involved in the regulation of defense response to pathogens and tolerance against abiotic stresses by jasmonic acid/ethylene-dependent signaling pathway.
    Differential Gene and Protein Expression in Soybean at Early Stages of Incompatible Interaction with Phytophthora sojae
    LI Yong-gang, YANG Ming-xiu, LI Yan, LIU Wen-wen, WEN Jing-zhi and LI Yong-hao
    2011, 10(6): 902-910.  DOI: 10.1016/S1671-2927(11)60075-8
    Abstract ( )   PDF in ScienceDirect  
    Soybean root and stem rot caused by Phytophthora sojae is a destructive disease worldwide. Using genetic resistance is an important and major component in the integrated pest management of this disease. To understand molecular mechanisms of root and stem rot resistance in soybeans, the gene and protein expression in hypocotyls and stems of variety Suinong 10 carrying resistance genes Rps1a and Rps2 was investigated by using mRNA differential display reverse transcription PCR and two-dimensional electrophoresis at 0, 0.5, 1, 2, and 4 h after inoculation with P. sojae race 1. The results of the comparison of gene and protein expression showed that at least eight differential fragments at the transcriptional level were related to metabolic pathway, phytoalexin, and signal transduction in defense responses.Sequence analyses indicated that these fragments represented cinnamic acid 4-hydroxylase gene, ATP β gene coding ATP synthase β subunit and ubiquitin-conjugating enzyme gene which upregulated at 0.5 h post inoculation, blue copper protein gene and UDP-N-acetyl-α-D-galactosamine gene which upregulated at 2 h post inoculation, TGA-type basic leucine zipper protein TGA1.1 gene, cyclophilin gene, and 14-3-3 protein gene which upregulated at 4 h post inoculation.Three resistance-related proteins, α-subunit and β-subunit of ATP synthase, and cytochrome P450-like protein, were upregulated at 2 h post inoculation. The results suggested that resistance-related multiple proteins and genes were expressed in the recognition between soybean and P. sojae during zoospore germination, penetration and mycelium growth of P. sojae in soybean.
    Regional Evaluation of Winter Rapeseed Response to K Fertilization, K Use Efficiency, and Critical Level of Soil K in the Yangtze River Valley
    ZOU Juan, LU Jian-wei, LI Yin-shui and LI Xiao-kun
    2011, 10(6): 911-920.  DOI: 10.1016/S1671-2927(11)60076-X
    Abstract ( )   PDF in ScienceDirect  
    The investigation was carried out to study the response of winter rapeseed to potassium (K) feritlization and the critical soil available K level for current winter rapeseed production in the Yangtze River Valley (YRV) of China. A total of 132 field experiments were conducted in fields of farmers in the major winter rapeseed growing areas in YRV in 2000/2001 and 2004/2005 to 2006/2007 during growing season. Results of these field experiments showed that the average rapeseed yield increment resulting from 100 kg K ha-1 application was 358 kg ha-1, an increase over the control CK (no K) of 18.0% in 2005/2006 and 2006/2007. The average internal use efficiency (IE) of K was higher in the CK treatment (21.9 kg grain, kg-1 K uptake) than in the +K (100 kg K ha-1) treatment (17.7 kg grain, kg-1 K uptake). Winter rapeseed required 68.1 kg of K to produce 1 000 kg seed. The recovery efficiency of K fertilizer in rapeseed production averaged 39.3%. The K balance was negative, with an average net removal of 117.6 kg K ha-1 in the CK treatment annually, and 56.8 kg K ha-1 in the +K treatment. The results indicated that there was a significant negative relationship between yield increments by K application and soil available K content. Based on the relative yield of CK/+K at 90% level, the critical level of soil available K(NH4OAc-extractable K) was 135 mg kg-1.
    Yield and Quality Response of Cucumber to Irrigation and Nitrogen Fertilization Under Subsurface Drip Irrigation in Solar Greenhouse
    ZHANG He-xi, CHI Dao-cai, WANG Qun, FANG Jun, FANG Xiao-yu
    2011, 10(6): 921-930.  DOI: 10.1016/S1671-2927(11)60077-1
    Abstract ( )   PDF in ScienceDirect  
    The aims of this research were to compare subsurface drip irrigation scheduling and nitrogen fertilization rates in cucumber,and evaluate yield and quality of cucumber fruit, water (WUE), irrigation water (IWUE), and nitrogen use (NUE) efficiencies in the solar greenhouse in Southwest China. The irrigation water amounts were determined based on the 20 cm diameter pan (Ep) placed over the crop canopy, and cucumber plant was subjected to three irrigation water levels (I1, 0.6 Ep; I2, 0.8 Ep;and I3, 1.0 Ep) in interaction with three nitrogen fertilization levels (N1, 300 kg ha-1; N2, 450 kg ha-1; and N3, 600 kg ha-1). The results showed that the cucumber fruit yield increased with the improvement of irrigation water. Irrigation water increased yields by increasing the mean weight of the fruits, and also by increasing fruit number. But the highest values of IWUE and WUE were obtained from I2 treatment. NUE significantly decreased with the improvement of N application, but increased by irrigating more water. The quality of cucumber fruit decreased with the improvement irrigation water and nitrogen fertilization. In conclusion, the optimum irrigation level and nitrogen fertilizer application level for cucunber under subsurface drip irrigation in the solar greenhouse in Southwest China were 0.8 Ep and 450 and 600 kg ha-1, respectively.
    Erythropoietin Receptor Gene (EPOR) Polymorphisms are Associated with Sow Litter Sizes
    ZHANG Long-chao, WANG Li-gang, LI Yong, YAN Hua, ZHAO Ke-bin and WANG Li-xian
    2011, 10(6): 931-937.  DOI: 10.1016/S1671-2927(11)60078-3
    Abstract ( )   PDF in ScienceDirect  
    The erythropoietin receptor (EPOR) has shown to play an important role in fetal survival by promoting the maturation of red blood cells in many studies of uterine capacity and litter size in swine. In this study, we screened the porcine EPOR gene for mutations and identified five single nucleotide polymorphisms (SNPs): g.705G>T in intron 1, g.2 373C>T in intron 4, and g.2 882C>T, g.3 035A>G, and g.3 132A>T in intron 6. We then genotyped 247 Beijing Black (BB) sows and compared the polymorphism data with the litter sizes of 1 375 parities among the sows. At first parity, there was no association of g.2 882C>T and g.3 132A>T with litter sizes. However, the CT sows in g.2 882C>T had 2.13 higher total number born (TNB) (P<0.01) and 1.81 higher number born alive (NBA) (P<0.01) than the CC sows and the heterozygous sows in g.3 132A>T had the highest litter size when compared to the two homozygotes for the later parities (P<0.05). In the g.3 035A>G SNP, for the later parities, the TNB of the sows with the GG genotype was 3.81 higher (P<0.01) and the NBA was 2.75 higher (P<0.01) than that with the AA genotype but no difference at first parity. The G allele of the EPOR g.705G>T SNP was associated with a greater litter size at both the first parity (P<0.05) and later parities (P<0.01). Furthermore, we determined the allele frequencies for this SNP among five Chinese indigenous pig breeds (Erhualian, Laiwu Black, Meishan, Min, and Rongchang) and three western commercial pig breeds (Duroc, Landrace, and Large White). The G allele of the EPOR g.705G>T SNP was significantly more common in the more prolific Chinese breeds. These results indicated that the EPOR could be an important candidate gene for litter size and g.705G>T can serve as a useful genetic marker for improving litter size in both first and later parities in swine.
    Effect of Dietary Supplementation with Hydrolyzed Wheat Gluten on Growth Performance, Cell Immunity and Serum Biochemical Indices of Weaned Piglets (Sus scrofa)
    WANG Xiu-qi, FENG You, SHU Gang, JIANG Qing-yan, YANG Jing-pei, ZHANG Zi-feng
    2011, 10(6): 938-945.  DOI: 10.1016/S1671-2927(11)60079-5
    Abstract ( )   PDF in ScienceDirect  
    To investigate the effects of dietary supplementation with hydrolyzed wheat gluten (HWG) on growth performance, cell immunity and serum biochemical indices of weaned piglets, 160 crossed (Large White x Landrace) and weaned piglets were randomly divided into 4 treatments with 4 replicates of 10 piglets each. The piglets in each treatment were fed an experimental diet containing either 0 g kg-1 HWG (control group), 30 g kg-1 HWG (3% HWG group), 50 g kg-1 HWG (5% HWG group), or 2.5 g kg-1 glycyl-L-glutamine (0.25% Gly-Gln group). The results showed that the diarrhea rates in 3% HWG and 5% HWG groups were significantly lower than in control group from d 1 to 14 (P<0.05). When compared with control group, dietary supplementation with 3% HWG increased the ratio of CD4 +:CD8 + and the ratio of serum albumin and globulin concentrations (A:G) on d 14 and 28, as well as the proliferation of T- and B-lymphocytes (P>0.05) on d 28. In addition, on d 14 and 28, the A:G ratio in 5% HWG group was significantly higher than in control group (P0.05). Interestingly, 0.25% Gly-Gln group had higher proportion of CD3 + (P>0.05) and CD4 + (P<0.05) on d 14 than control group, but growth performances of 0.25% Gly-Gln group were negatively affected at all experiment stages. These results suggested that HWG might improve the growth performance of piglets by strengthening cell immunity and decreasing the occurrence of diarrhea during the prophase after weaning.
    Identification and Phylogenetic Analysis of an Orf Virus Isolated from an Outbreak in Boer Goat in Shanxi Province
    GU Shao-peng, SHI Xin-tao, SHI Zhong-yong, WANG Zhong-bing and ZHENG Ming-xue
    2011, 10(6): 946-953.  DOI: 10.1016/S1671-2927(11)60080-1
    Abstract ( )   PDF in ScienceDirect  
    To identify and analyze the Orf virus in Shanxi Province, China, an Orf virus strain was successfully isolated from crust materials of boer goat with clinical sore mouth symptom from a goat farm of Shanxi Province by passaging in lamb testis (LT). The Orf virus was identified by enzyme linked immunosorbent assay (ELISA) test, recurrent infection test, transmission electron microscopy, and PCR. The nucleotide and amino acid sequences of two genes of the Orf virus were analyzed.The results showed that under the electron microscopy the virus had a presence of typical parapoxvirus virions and there were many eosinophilic intracytoplasmic inclusions observed by hematoxylin-eosin (H&E) stain. In ELISA test, optical density (OD) readings of the sample showed a positive result, and the rabbits infected with the virus showed a typically Orf virus-infected appearance. All these findings proved that the sample was an Orf virus. The phylogenetic studies of Orf B2L and Orf F1L genes showed that the virus clustered in different branches and were closer to the Orf virus Nantou (DQ904351) and the OV-SA00 isolates (AY386264). Furthermore, the above results may provide some insight into the genotype of the etiological agent responsible for the Orf outbreak in Shanxi Province, and could also provide a comparative view of the B2L and F1L genes of parapoxvirus.
    Lactic Acid Inhibits NF-κB Activation by Lipopolysaccharide in Rat Intestinal Mucosa Microvascular Endothelial Cells
    LIU Jing, XUE Jiu-zhou, ZHU Zhi-ning, HU Ge, REN Xiao-ming
    2011, 10(6): 954-959.  DOI: 10.1016/S1671-2927(11)60081-3
    Abstract ( )   PDF in ScienceDirect  
    To investigate whether lactic acid could inhibit the LPS-activation of NF-κB p65 in rat intestinal mucosa microvascular endothelial cells (RIMMVECs), RIMMVECs, cultured in vitro, were pretreated with different concentrations of lactic acid and then exposed to lipopolysaccharide (LPS). Cells and cell culture media were then collected at different time intervals.Production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) was examined at the protein level by enzyme-linked immunosorbent assay. The influence of lactic acid on the LPS-activation of NF-κB was examined at mRNA and protein levels by real-time quantitative PCR and Western blot analysis, respectively. TNF-α and IL-6 protein levels were significantly decreased after pretreatment with lactic acid compared with cells exposed to LPS only. After pretreatment with 7.5, 5.0, and 2.5 μL mL-1 lactic acid, NF-κB mRNA levels were increased by 1.51-, 2.62- and 3.00-fold, respectively, compared with levels in control cells without LPS treatment. Western blot analysis indicated that the level of NF-κB p65 in the lactic acidpretreated group was significantly lower than that in the group treated with LPS only (positive control) and was unchanged compared with the group without LPS treatment (blank control). These results suggest that lactic acid may inhibit LPSactivation of NF-κB, leading to the down-regulation of TNF-α and IL-6.
    Physico-Chemical Properties of Flour, Starch, and Modified Starch of Two Rice Varieties
    LIN Qin-lu, XIAO Hua-xi, FU Xiang-jin, TIAN Wei, LI Li-hui, YU Feng-xiang
    2011, 10(6): 960-968.  DOI: 10.1016/S1671-2927(11)60082-5
    Abstract ( )   PDF in ScienceDirect  
    The physical and chemical properties of the flours, starches, and modified starches of indica rice and japonica rice were investigated in this paper. Results showed that the swelling powers of flour, starch, and phosphate starch [substitution degree (DS)=0.065] of japonica rice were significantly higher than those (DS=0.065) of indica rice. The transmittance of modified starches was highest; and that of flours was lowest. The pasting property investigated with rapid visco analyzer (RVA) indicated that the peak viscosity and breakdown value of paste with high swelling power were high. Furthermore,the effect of protein and amylose content on pasting property were investigated. The results of rheological properties determined using rheological rheometer showed that at the same temperature, the storage modulus (G') of flour, starch,and modified starch of indica rice was higher than that of japonica rice. For each variety, the G' of flour was the highest,while the G' of modified starch was the lowest.
    Effects of Chemical Components on the Amount of Green Tea Cream
    XU Yong-quan, CHEN Su-qin, SHEN Dan-yu and YIN Jun-feng
    2011, 10(6): 969-974.  DOI: 10.1016/S1671-2927(11)60083-7
    Abstract ( )   PDF in ScienceDirect  
    The relationship between the amount of tea cream and the chemical components contents in the original green tea infusion was investigated. The results showed that the amounts of tea cream in the green tea infusions obtained from different cultivars and different parts of new shoots were varied. There were many chemical components participating in the formation of green tea cream. However, there were only the contents of caffeine (Y=0.85, P<0.01) and polyphenols (Y=0.65,P<0.05) in the original green tea infusion highly correlated with the amount of green tea cream. Stepwise regression analysis of overall chemical components indicated that the contents of caffeine and gallated catechins in the original green tea infusion had a significant effect (P<0.01) on green tea cream levels. Cream (g L-1)=-172.071+ 0.129 x Ccaffeine+0.024xGgallated catechins (R2=0.936). The amount of green tea cream can be predicted by the contents of gallated catechins and caffeine in the original tea infusion. Principal component analysis also indicated that catechins, minerals, and polysaccharides were the important chemical components in the formation of green tea cream.