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61.
This study indicated that by applying an improved classification system to decayed large-diameter Norway spruce (Picea abies) wood, its use as raw material for kraft pulping without loss of pulp quality could be essentially increased. This is based on the fact that although the cooking yield of decayed spruce material which has been sorted according to these new recommendations is somewhat lower and Kappa number higher than those of sound wood material, the greatest part of the decayed stem (the outer part of the stem) contains long-fiber wood material which produces pulp of good quality. Therefore, large-diameter spruce logs can also be separately used, for example, in the manufacture of reinforcement pulp.  相似文献   
62.
In recent years, there has been an increasing interest in investigating the carcinogenicity of mycotoxins in humans. This systematic review aims to provide an overview of data linking exposure to different mycotoxins with human cancer risk. Publications (2019 and earlier) of case–control or longitudinal cohort studies were identified in PubMed and EMBASE. These articles were then screened by independent reviewers and their quality was assessed according to the Newcastle–Ottawa scale. Animal, cross‐sectional, and molecular studies satisfied criteria for exclusion. In total, 14 articles were included: 13 case–control studies and 1 longitudinal cohort study. Included articles focused on associations of mycotoxin exposure with primary liver, breast, and cervical cancer. Overall, a positive association between the consumption of aflatoxin‐contaminated foods and primary liver cancer risk was verified. Two case–control studies in Africa investigated the relationship between zearalenone and its metabolites and breast cancer risk, though conflicting results were reported. Two case–control studies investigated the association between hepatocellular carcinoma and fumonisin B1 exposure, but no significant associations were observed. This systematic review incorporates several clear observations of dose‐dependent associations between aflatoxins and liver cancer risk, in keeping with IARC Monograph conclusions. Only few human epidemiological studies investigated the associations between mycotoxin exposures and cancer risk. To close this gap, more in‐depth research is needed to unravel evidence for other common mycotoxins, such as deoxynivalenol and ochratoxin A. The link between mycotoxin exposures and cancer risk has mainly been established in experimental studies, and needs to be confirmed in human epidemiological studies to support the evidence‐based public health strategies.  相似文献   
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At present, much attention is paid to the use of antimicrobial peptides (AMPs) of natural and artificial origin to combat pathogens. AMPs have several points that determine their biological activity. We analyzed the structural properties of AMPs, as well as described their mechanism of action and impact on pathogenic bacteria and viruses. Recently published data on the development of new AMP drugs based on a combination of molecular design and genetic engineering approaches are presented. In this article, we have focused on information on the amyloidogenic properties of AMP. This review examines AMP development strategies from the perspective of the current high prevalence of antibiotic-resistant bacteria, and the potential prospects and challenges of using AMPs against infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).  相似文献   
65.
Tissues and biofluids are important sources of information used for the detection of diseases and decisions on patient therapies. There are several accepted methods for preservation of tissues, among which the most popular are fresh‐frozen and formalin‐fixed paraffin embedded methods. Depending on the preservation method and the amount of sample available, various specific protocols are available for tissue processing for subsequent proteomic analysis. Protocols are tailored to answer various biological questions, and as such vary in lysis and digestion conditions, as well as duration. The existence of diverse tissue‐sample protocols has led to confusion in how to choose the best protocol for a given tissue and made it difficult to compare results across sample types. Here, we summarize procedures used for tissue processing for subsequent bottom‐up proteomic analysis. Furthermore, we compare protocols for their variations in the composition of lysis buffers, digestion procedures, and purification steps. For example, reports have shown that lysis buffer composition plays an important role in the profile of extracted proteins: the most common are tris(hydroxymethyl)aminomethane, radioimmunoprecipitation assay, and ammonium bicarbonate buffers. Although, trypsin is the most commonly used enzyme for proteolysis, in some protocols it is supplemented with Lys‐C and/or chymotrypsin, which will often lead to an increase in proteome coverage. Data show that the selection of the lysis procedure might need to be tissue‐specific to produce distinct protocols for individual tissue types. Finally, selection of the procedures is also influenced by the amount of sample available, which range from biopsies or the size of a few dozen of mm2 obtained with laser capture microdissection to much larger amounts that weight several milligrams.  相似文献   
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黎瑶依  胡小霞  黄永光 《食品科学》2021,42(18):164-170
采用高通量测序技术结合数理统计软件分析方法,系统研究茅台镇酱香型白酒不同酿造轮次生产环境中的真菌菌群结构及特征。7 个轮次中共检测到4 个真菌门、212 个真菌属。根据各菌门、属的相对丰度,子囊菌门(Ascomycota)和担子菌门(Basidiomycota)是茅台镇酱香型白酒酿造环节中各酿造轮次的优势菌门,节担菌属(Wallemia)、复膜孢酵母属(Saccharomycopsis)为各轮次绝对优势真菌属。不同轮次环境样品中真菌组成结构的相似度较高,但其各轮次标志性真菌属存在差异。7 个酿造轮次共有相同真菌属56 个,在各轮次占主导地位,特征性真菌属在各轮次当中相对丰度和占比较小但种类丰富。Ascomycota最强节点为德巴利酵母属(Debaryomyces),Basidiomycota最强节点为红酵母属(Rhodotorula)。本研究揭示了茅台镇酱香型白酒不同酿造轮次环境中真菌菌群结构及其特征,为深入研究酱香型白酒酿造机理以及对酿造环境中微生物结构的解析提供了参考依据。  相似文献   
68.
ABSTRACT

There is an increasing demand for fungi control in grains, especially toxigenic. Also, there is growing concern on the use of synthetic fungicides; thus alternatives are needed. The aim of this study was to evaluate the antifungal and antimycotoxigenic action of essential oils (EOs) from Zingiber officinale, Cinnamomum zeylanicum and Cymbopogon martinii against Fusarium verticillioides, a spoilage and toxigenic fungus. Essential oils were first chemically characterised by gas chromatography coupled to mass spectrometry, and their antioxidant potential was measured by the DPPH, ABTS and FRAP methods. Minimum inhibitory concentration (MIC) and disc diffusion were used to assess antifungal activity. Scanning electron microscopy was used to evaluate morphological changes in the fungus. Antimycotoxigenic activity of the EOs against the production of fumonisin B1 and B2 by F. verticillioides was evaluated using ultra-high-performance liquid chromatography system. Z. officinale, C. zeylanicum and C. martinii EOs were predominantly composed by zingiberene and geranial; eugenol; and geraniol, respectively. All the EOs had high antioxidant power, especially that from C. zeylanicum. The MICs were 250, 500 and 2,000 µg mL?1 for C. zeylanicum, C. martinii and Z. officinale EOs, respectively. Mycelial reduction of F. verticillioides was observed when EOs were used, and the lowest activity was detected in the Z. officinale EO. Overall, the tested EOs promoted structural damage to the fungal cell wall, decreased conidia size and mycelial reduction. Antimycotoxigenic evaluation of the EOs evidenced a significant reduction (p < .05) in the production of fumonisins B1 and B2 with all the EOs evaluated in the study. These results suggest that especially C. zeylanicum and C. martinii EOs are highly useful for controlling F. verticillioides and fumonisins production.  相似文献   
69.
The present review covers modern aspects of combinatorial peptide ligand libraries (CPLL), as used to analyze the "low-abundance proteome" in association with mass spectrometry. First, the capturing properties of baits of different lengths (from single amino acid to hexa-peptides) are described to show that a plateau is rapidly reached above a tetra-peptide in length, thus confirming the validity of having adopted hexapeptides for the considered application. The mechanism of interaction with proteins from very complex proteomes and the ability to decrease the dynamic concentration range is demonstrated with the help of mass spectrometry analysis. Examples are given on how treatment with CPLLs dramatically improves the detectability of peptides in mass spectrometry analysis, permitting detection of a very large number of proteins as compared with control, untreated samples. The use of complementary libraries is discussed with the aim to discover additional low-abundance species that escaped the first library. A discussion on the possibility to discover extremely rare gene products, and the quantitative aspect of the technology when associated with mass spectrometry is also provided. Some insights on the applications for hidden, low-abundance biomarkers are also presented.  相似文献   
70.
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