Effect of microwave pre-treatment on physical quality,bioactive compounds,safety risk factor,and storage stability of peanut butter

Microwave, as a new heat treatment technology, has the characteristics of uniform and fast heating speed. It is an energy-saving technology known for improving oilseed product quality. Its efficiency mainly depends on the roasting power and time. However, the production of high-quality peanut butter using short-time roasting conditions are limited. Herein, we determined an appropriate microwave roasting power and time for peanuts and evaluated its impacts on the quality of peanut butter. Different roasting powers (400 ​W, 800 ​W and 1200 ​W) and times (4, 4.5, 5, and 5.5 ​min) were preliminarily tested. Among them, 800 ​W at 5 ​min was the most suitable. The roasting efficiency was further evaluated using color, sensory, bioactive compounds, storage stability, and safety risk factors of peanut butter produced from four peanut cultivars (Silihong, Baisha-1016, Yuanza-9102, and Yuhua-9414). The pre-treated butter obtained from three cultivars (Silihong, Yuanza-9102, and Yuhua-9414) with moisture content between 5% and 7.2% had a similar sensory score (6–7) as the commercial on a 9-point hedonic scale compare to the other. The color of the pre-treated peanut butter varies statistically with the commercial but remained in the recommended range of Hunter L1 values of 51–52, respectively, for high initial moisture peanut cultivars. The total polyphenol (35.20-31.59 ​± ​0.59 ​μmol GAE/g) and tocopherol (19.05 ​± ​0.35 ​mg/100 ​g) content in the butter obtained from three cultivars (Yuahua-9102, Yuhua, and Baisha-1016) and Silihong respectively, were significantly (P ​< ​0.05) higher than those in the commercial butter. The induction times of all pre-treated butter (19.80 ​± ​0.99–7.84 ​± ​0.07 ​h) were significantly (P ​< ​0.05) longer during storage at accelerated temperature than commercial samples. In addition, no benzo[a]pyrene was found in the pre-treated samples. Collectively, the microwave pretreated peanut butter was superior to the commercial one. These findings provided data support and a reference basis to promote microwave use for peanut butter production.     

Comparison of flagellin and an oil-emulsion adjuvant in inactivated Newcastle disease vaccine in stimulation of immunogenic parameters

The present study was designed to investigate the potential application of native (N) and recombinant (truncated modified [tmFliC] and full-length [flFliC]) flagellin proteins along with inactivated Newcastle disease virus (NDV). Fifty six SPF chickens were immunized twice with PBS (control), inactivated NDV (Ag), inactivated NDV/flFliC (AgF), inactivated NDV/tmFliC (AgT), inactivated NDV/N (AgN), commercial vaccine containing Montanide (Vac) and Vac/N (VacN), with a two-week interval. Blood was collected weekly and spleens were harvested after chickens were sacrificed. Interleukin-6 (IL-6) and tumor necrotic factor-α (TNF-α) gene expression in peripheral blood mononuclear cells were analyzed by Real-Time PCR. Antibody response was assessed by haemagglutination inhibition (HI). Cellular activity was quantified by MTT assay. Results showed that the most IL-6 and TNF-α gene expression was observed in AgF group (P < 0.01). The lowest gene expression among vaccinated groups was observed in Ag group for IL-6 and Ag and Vac group for TNF-α. The highest HI titer was observed in Vac, VacN, AgF and AgT groups. The AgF group showed the highest cellular activity (P < 0.01). In conclusion, flagellin-adjuvanted groups showed a pro-inflammatory effect and acted similarly to or better than the Vac group. Hence, flagellin can be proposed as a potential adjuvant for ND vaccine.     

甜菜BvGSTU9基因的生物信息学及在镉胁迫下的表达分析

为了进一步研究甜菜谷胱甘肽转移酶BvGSTU9 (LOC104894060)在重金属胁迫过程中的功能。本研究以‘780016B/12优’为实验材料,对该基因序列特征、结构、功能进行预测分析,并利用qPCR检测该基因在不同浓度镉胁迫下的表达量变化。结果显示甜菜BvGSTU9基因全长925 bp,开放阅读框675 bp,编码了由224个氨基酸组成的不稳定膜外蛋白。BvGSTU9与菠菜、藜麦的氨基酸序列相似性较高,与系统发育进化树分析结果基本相符。二级和三级结构预测表明该基因主要由α-螺旋、β-折叠、延伸链及无规则卷曲组成。qPCR显示BvGSTU9基因在不同浓度的镉胁迫下均受到不同程度的诱导,因此可以推断甜菜BvGSTU9基因无论从结构还是功能上,与镉逆境胁迫存在着一定的应答关系。研究结果也为甜菜耐重金属镉机制研究提供参考依据。     

SnToxA,SnTox1, and SnTox3 originated in Parastagonospora nodorum in the Fertile Crescent

The centre of origin of the globally distributed wheat pathogen Parastagonospora nodorum has remained uncertain because only a small number of isolates from the Fertile Crescent were included in earlier population genetic and phylogeographic studies. We isolated and genetically analysed 193 P. nodorum strains from three naturally infected wheat fields distributed across Iran using 11 neutral microsatellite loci. Compared to previous studies that included populations from North America, Europe, Africa, Australia, and China, the populations from Iran had the highest genetic diversity globally and also exhibited greater population structure over smaller spatial scales, patterns typically associated with the centre of origin of a species. Genes encoding the necrotrophic effectors SnToxA, SnTox1, and SnTox3 were found at a high frequency in the Iranian population. By sequencing 96 randomly chosen Iranian strains, we detected new alleles for all three effector genes. Analysis of allele diversity showed that all three effector genes had higher diversity in Iran than in any population included in previous studies, with Iran acting as a hub for the effector diversity that was found in other global populations. Taken together, these findings support the hypothesis that P. nodorum originated either within or nearby the Fertile Crescent with a genome that already encoded all three necrotrophic effectors during its emergence as a pathogen on wheat. Our findings also suggest that P. nodorum was the original source of the ToxA genes discovered in the wheat pathogens Phaeosphaeria avenaria f. sp. tritici 1, Pyrenophora tritici-repentis, and Bipolaris sorokiniana.     

Genetic variation of seedling traits responded to brassinosteroid and gibberellin inhibitors in maize (Zea mays) doubled haploid lines

The purpose of this study was to examine the genotypic variation in maize doubled haploid (DH) lines response to brassinosteroid and gibberellin inhibitors. Plant responses to hormone inhibitors were determined in growth chamber experiments using germination paper for three different seedling treatments: application of propiconazole (Pcz), uniconazole (Ucz) or water (control). Mesocotyl length (ML) was more sensitive to hormone inhibitors, especially to the Ucz treatment, than other seedling traits. ML was significantly correlated with other traits in the Ucz treatment. All the seedling traits showed moderate-to-high broad sense heritability values, ranging from 0.39 to 0.82. The Euclidian genetic distances of inbred line pairs ranged from 1.27 to 19.94, indicating there was a high level of variability across the maize DH lines used in this study. DH lines with extreme MLs were identified, which can provide valuable breeding resources for improving abiotic stress tolerance, and for further genetic studies.     

玉米HD-ZIP I亚家族基因鉴定及表达分析

转录因子是植物响应逆境胁迫的重要调节因子,在其整个生长发育过程中发挥着重要的作用。HD-ZIP家族蛋白是植物中特有的一大类转录因子,包含4个亚家族(HD-ZIP I^IV),其中HD-ZIP I亚家族成员主要参与干旱、渗透压等极端环境和ABA及乙烯等激素处理的响应过程。本文采用隐马可夫模型(HMM)在玉米参考基因组中鉴定到17个HD-ZIP I亚家族成员,这些基因不均匀分布于玉米6条染色体上,与水稻的亲缘关系要近于拟南芥。玉米HDZIP I亚家族基因在玉米7种组织中表现出多种表达模式,具有明显的组织表达特异性。另外, HD-ZIP I亚家族基因对高盐、淹水及冷害等不同的逆境胁迫处理呈现出不同的响应模式及响应程度差异。5种不同激素处理后,玉米HD-ZIP I亚家族基因也表现出复杂的响应模式。这些结果为进一步解析玉米HD-ZIP I亚家族基因的生物学功能和作用机理提供了一定的参考价值。     

小麦矮腥黑粉菌侵染小麦子房的激光共聚焦显微观察方法

本试验利用碘化丙啶(propidium iodide)和Alexa Flour 488(AF 488)标记的麦胚凝集素(WGA)分别对小麦子房细胞和小麦矮腥黑粉菌进行染色,结合激光共聚焦显微镜成像系统获取小麦子房的三维立体图像。该技术可获得清晰的小麦子房细胞图像,并观察小麦矮腥黑粉菌在小麦子房中的侵染状况。该方法将为研究病原菌在寄主体内的分布提供可参考依据。     

小麦芒长抑制基因B2的精细定位与候选基因分析

芒是小麦重要的穗部器官和形态特征,是小麦长期进化和适应环境的结果,对产量和抗旱性等具有重要影响。目前,对麦芒的遗传与发育还缺乏系统的研究,相关基因克隆或精细定位的研究尚未见报道。本试验利用短芒材料‘六柱头’与长芒材料‘石矮1号’构建的F2群体(SL-F2)对芒的遗传与发育进行了研究。细胞学观察表明,短芒主要是由细胞长度变短引起;遗传分析表明,‘六柱头’的短芒由显性单基因控制;借助Wheat660K SNP芯片的BSA分析和SL-F2群体的精细定位,确定‘六柱头’的芒长抑制基因是前人报道的B2位点,并将其定位到6B染色体4.84Mb的物理区间(471.28～476.12 Mb)内,该区段在中国春与矮抗58间具有良好的共线性。在B2定位区间共有61个基因,其中5个在中国春穗部特异表达,TraesCS6B02G264400在中国春和Azhurnaya幼穗表达差异显著。这些研究结果为B2基因的克隆、小麦芒形成机理的解析及育种中的应用奠定了基础。     

利用CRISPR/Cas9敲除葡萄VviPDS1基因的研究

选择葡萄八氢番茄红素脱氢酶(Phytoene desaturase)基因VviPDS1为靶标,利用CRISPR/Cas9系统构建基因敲除载体,瞬时转化葡萄叶片原生质体,检测到不同类型的突变。通过农杆菌介导转化‘无核白’葡萄胚性愈伤组织,筛选获得卡那霉素抗性植株71株。经PCR鉴定,其中53株为阳性植株,阳性率为74.64%。测序结果表明,共有20株在靶点发生不同类型的突变,编辑效率为37.74%;其中9株产生了双等位基因突变。对其进行氨基酸序列预测,在第202位氨基酸之后发生了不同程度的变异。利用CRISPR/Cas9系统敲除VviPDS1获得的突变体植株呈现整体矮化,其叶片出现不同程度白化。表明CRISPR/Cas9系统可以通过细胞中的瞬时或稳定表达进行基因编辑,可以实现在葡萄编辑植株中产生纯合敲除。     

解淀粉芽胞杆菌YU-1对水稻纹枯病的防治作用

本文旨在筛选对水稻纹枯病有生防作用的菌株,并初步探索其生防作用机理。收集水稻、甘蓝、黄瓜等不同植物根际土壤,采用稀释分离和对峙培养法筛选对水稻纹枯病菌Rhizoctonia solani Kühn有抑菌作用的菌株;通过离体接种防效、盆栽防效、抑菌谱、对水稻纹枯病菌菌核萌发及形成的抑制作用等方面评价其生防潜力,并对生防菌株进行鉴定。结果表明,从采集的37份根际土壤中共分离获得细菌297株,其中4株对纹枯病菌具有较好的拮抗作用,菌株YU-1对水稻纹枯病菌菌丝生长的抑制率达89.8%;对西瓜枯萎病菌、草莓灰霉病菌、番茄早疫病菌、油菜菌核病菌、小麦赤霉病菌菌丝生长的抑制率均在85%以上;对水稻纹枯病的离体和盆栽防效分别为73.1%和66.3%;对水稻纹枯病菌菌核萌发的抑菌率在92%以上;经生理生化和分子鉴定为解淀粉芽胞杆菌Bacillus amyloliquefaciens。由此可看出,菌株YU-1对水稻纹枯病的防治具有较强的应用价值,具有进一步开发成生物农药的潜力。