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51.
烟梗是烟草工业的重要副产物,也是宝贵的自然资源。本研究首先利用白腐菌漆酶对烟梗丝进行预处理,提升了添加烟梗丝的卷烟品质;然后分别以木质素、纤维素、半纤维素和果胶的降解率为响应值,采用Box-Behnken设计建立方程模型,对漆酶、纤维素酶、半纤维素酶和果胶酶组成的复合酶预处理烟梗丝条件进行了优化。结果表明:每100g烟梗丝加入30U漆酶,在料液比为35%、温度为30℃、酶解pH为5处理48h的条件下预处理的烟梗丝对提升卷烟品吸效果最佳,烟梗丝中木质素、纤维素、半纤维素和果胶的降解率分别为20.16%、15.10%、7.20%和12.40%;为获得与之相同的各组分降解率,响应面法优化漆酶复合酶最佳处理条件为:每100g烟梗丝加入漆酶14.72U、纤维素酶1.00U、半纤维素酶1.00U、果胶酶8.45U。验证发现烟梗丝各组分降解率实测值与理论值无显著性差异,且显微结构观察显示复合酶处理后的烟梗丝表面致密结构被破坏,孔洞数量明显增加。本研究获得的白腐菌漆酶预处理后的烟梗丝在卷烟中的添加能有效改善卷烟品质,且漆酶复合酶的使用大幅减少了漆酶的用量,降低了漆酶预处理烟梗丝的成本,为废弃烟梗生物质的资源化利用提供了重要依据。  相似文献   
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麦红吸浆虫Sitodiplosis mosellana(Gehin)是一种世界性的小麦害虫。为获得其转录组信息,本研究采用新一代高通量测序技术Illumina HiSeq TM 2000对麦红吸浆虫成虫转录组进行测序。共获得转录组样本数据量为27.88 G,经分析共获得59257个Unigenes,总长度49861164 bp,最短20 bp,最长29282 bp,平均长度841 bp。将Unigenes序列与NR、NT、Swiss-Prot、KEGG、GO和KOG数据库进行比对(e≤10-10),共获得95029个结果。通过GO功能分类,共有19584个Unigenes在GO数据库中细胞组分、分子功能和生物学过程等3大类50个功能组中找到对应。与KOG数据库进行比对,共有11279个麦红吸浆虫Unigenes被注释,按功能大致可分为26类。通过KEGG pathways分析,共有9110个麦红吸浆虫Unigenes被注释,分别归属于细胞进程、环境信息进程、遗传信息进程、新陈代谢和有机体系统5大类代谢途径,主要包括细胞生长与死亡、细胞运动、信号转导、能量代谢等32类代谢途径。CDS预测发现30088条序列可被编码,占全部基因的50.78%。SSR位点查找发现,在59257个Unigenes中共找到36323个SSR位点,发生率为61.30%。本研究获得的巨大的麦红吸浆虫转录组信息,为麦红吸浆虫的功能基因挖掘提供了重要的信息资源。  相似文献   
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为阐明黄光光照强度对甜菜夜蛾Spodoptera exigua Hübner成虫生殖行为和寿命的影响。本研究设置3个光照强度(1 Lx,10 Lx,100 Lx)和一个对照(CK)处理,观察记录不同处理下甜菜夜蛾的单雌产卵量、产卵前期、产卵期、卵孵化率及成虫寿命。结果表明,黄光不同光照强度对甜菜夜蛾的生殖行为和雌成虫寿命均存在不同程度的影响,在光照强度达到10 Lx和100 Lx的情况下,其单雌产卵量明显降低,产卵历期和雌成虫寿命明显缩短,当光照强度为1 Lx情况下与对照相比无明显差异。该研究结论为防蛾灯的进一步优化和完善提供了一定的理论支撑。  相似文献   
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The composite filler micro-embedded with Pseudomonas putida (P. putida) was prepared and the biodegradation performance of the filler was evaluated in a biofilter. Five phases were set up to evaluate the performance of the biofilter under different toluene inlet loadings and transient shock loadings. In particular, the microbial community structure in the biofilms and fillers was measured by sequence analysis of the 16S rRNA gene. The results show that the biofilter packed with the composite fillers was suitable for the biodegradation of toluene. The biofilter could start up quickly with high removal efficiency (RE), and remain above 90 % RE when the empty bed residence time (EBRT) was 18 s and the inlet loading rates were not higher than 41.4 g/(m3·h). Moreover, the biofilter could tolerate substantial transient shock loadings. The high removal efficiency and elimination capacity contributed to rich bacterial communities for the efficient degradation of toluene. The dominant microbial communities at the phylum level were mainly Firmicutes, Actinobacteria and Proteobacteria. It is noteworthy that the abundance of Bacteroidetes at phylum level and Chungangia and Stenotrophomonas at genus level increased significantly during the re-start period.  相似文献   
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Cost effective bioprocessing of nutraceuticals in present global scenario is a matter of concern. This study explored Paper mill sludge (PMS) and sugarcane bagasse (SCB) as inexpensive substrate for Planococcus sp. TRC1 mediated valuable β-carotene production and residual treated biomass as value added crystalline cellulose source simultaneously. Both biomass supported significant bacterial growth reaching highest yield 38.54 ± 1.4 mg/g on PMS (36 h) and 47.13 ± 1.9 mg/g (48 h) on SCB in solid state fermentation. Luedeking-Piret model revealed growth associated production with α and much lower β values of 5.18 and 0.24 for PMS and 4.5 and 0.165 for SCB. Cost analysis exhibited decrementation of pigment cost/mg by 84 % compared to synthetic media. Optimum production conditions were 30 °C temperature, pH 7, 10 % inoculum and initial moisture content 80 % (PMS) and 85 % (SCB). TLC (Rf = 0.9), HPLC (RT = 7.646) and lambda max (465 nm) confirmed pigment’s β-carotene nature with significant antioxidant and antimicrobial activity. It showed stability at varied temperature, pH and light conditions along with negligible phytotoxicity on Vigna radiata. Planococcus sp. TRC1 delignified PMS (41 %) and SCB (38 %) and FT-IR, FESEM and XRD suggested crystalline nature of residual cellulose rich fraction shedding light on a biorefinery approach for valorization of industrial solid wastes.  相似文献   
59.
Systemic necrosis often occurs during viral infection of plants and is thought mainly to be the result of long-term stress induced by viral infection. Potato virus X (PVX) encodes the P25 pathogenicity factor that triggers a necrotic reaction during PVX-potato virus Ysynergistic coinfection. In this study, we discovered that NbALY916, a multifunctional nuclear protein, could interact with P25. When NbALY916 expression was reduced by tobacco rattle virus (TRV)-based virus-induced gene silencing, the accumulation of P25 was increased, which would be expected to cause more severe necrosis. However, silencing of NbALY916 reduced the extent of cell death caused by P25. Furthermore, we found that overexpression of NbALY916 increased the accumulation of H2O2 and triggered more extensive cell death when coexpressed with P25, even though accumulation of P25 was itself reduced by the increased expression of NbALY916. Furthermore, transient expression of P25 specifically induced the expression of NbALY916 mRNA, but not the mRNAs of three other ALYs in Nicotiana benthamiana. In addition, we showed that silencing of NbALY916 or transient overexpression of NbALY916 affected the infection of PVX in N. benthamiana. Our results reveal that NbALY916 has an antiviral role that, in the case of PVX, operates by inducing the accumulation of H2O2 and mediating the degradation of P25.  相似文献   
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《Endocrine practice》2020,26(8):869-882
Objective: Studies have shown that metabolic abnormalities influence the immune system. Because the prevalence of metabolic and autoimmune thyroid diseases has increased synchronously, the correlation between them was worth exploring. The study objective was to investigate the relationship between metabolic disorders and thyroid auto-antibodies in euthyroid subjects.Methods: Data were obtained from the Thyroid Diseases and Diabetes Mellitus project survey of 55,891 subjects from 31 provinces in China. The body mass index (BMI), waist circumference (WC), blood pressure, thyroid peroxidase antibodies (TPOAbs), thyroglobulin antibodies (TgAbs), thyroid-stimulating hormone (TSH), urinary iodine concentration, blood glucose, lipid profile, and uric acid levels were evaluated. Free thyroxine and free triiodothyronine levels were measured in patients with abnormal serum TSH levels.Results: In males, the BMI, WC, systolic blood pressure (SBP), diastolic blood pressure (DBP), and 2-hour post-glucose oral glucose tolerance test results of the TPOAb-/TgAb-positive group were significantly higher than those of the TPOAb-/TgAb-negative group. In females, the BMI, WC, SBP, DBP, total cholesterol, and low-density-lipoprotein cholesterol (LDL-C) in the TPOAb-/TgAb-positive group were significantly increased compared to the TPOAb-/TgAb-negative group. Multivariate analysis showed that in males, the odds ratio (OR) of positive TgAbs in the abdominal obesity group was 1.175 (95% confidence interval [CI], 1.016 to 1.359; P = .03), and the OR of positive TPOAbs in the hyperuricemia group was 1.195 (95% CI, 1.041 to 1.372; P = .011). In females, the OR of positive TgAbs was 1.19 (95% CI, 1.068 to 1.326; P = .002) in the high LDL-C group.Conclusion: Obesity, high LDL-C, and hyperuricemia were positively correlated with the prevalence of positive thyroid autoantibodies in euthyroid subjects in a gender-dependent manner. This cross-sectional survey showed that metabolic disorders are associated with increased positive thyroid autoantibody levels in euthyroid subjects in a gender-dependent manner.Abbreviations: AIT = autoimmune thyroiditis; BMI = body mass index; CI = confidence interval; DBP = diastolic blood pressure; FPG = fasting plasma glucose; FT3 = free triiodothyronine; FT4 = free thyroxine; HbA1c = glycated hemoglobin; HDL-C = high-density-lipoprotein cholesterol; LDL-C = low-density-lipoprotein cholesterol; OGTT2hPG = oral glucose tolerance test 2-hours post-glucose; OR = odds ratio; SBP = systolic blood pressure; TC = total cholesterol; TG = triglycerides; TgAb = thyroglobulin antibody; TPOAb = thyroid peroxidase antibody; TSH = thyroid-stimulating hormone; UA = uric acid; WC = waist circumference  相似文献   
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