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991.
Kaktcham Pierre Marie Zambou Ngoufack François Foko Kouam Edith Marius Oana Ciobotaru Florentina Matei Calina Petruta Cornea 《Food Biotechnology》2013,27(4):237-256
This study aims to evaluate the antifungal activity of lactic acid bacteria (LAB) from some Cameroonian food commodities against mycotoxigenic and spoilage molds. Following LAB isolation, the antifungal activity of the isolates was assessed. The organic acids were quantified using high-performance liquid chromatography and the ability of the LAB to reduce mold biomass and aflatoxin production was evaluated. The LAB were identified and the biopreservative potential of strain LO3 was evaluated on tomato paste. Nine percent of the strains isolated showed broad antifungal activity. The activity was due to the effect of organic acids comprising lactic, acetic, 4-hydroxy-3-phenyllactic and 3-phenyllactic acids. Lactobacillus plantarum LO3 exhibiting the highest and broadest antifungal activity was selected and showed the capacity to inhibit fungal growth and aflatoxin production in vitro. Moreover, this strain and its cell-free supernatant showed the ability to prevent aflatoxigenic mold growth in tomato paste without altering its physico-chemical and organoleptic properties. 相似文献
992.
The high density steam flash-explosion (HDSFE) was used to extract protein from soybean meal. Soybean meal samples were treated at 1.3 MPa and 1.8 MPa for 60 s, 120 s and 180 s, respectively. After HDSFE treatment at 1.8 MPa for 180 s, the extraction yield of protein was increased from 50.50% to 65.66% compared with untreated soybean meal. The emulsification properties and fat-binding capacity of soy protein isolate (SPI) extracted from soybean meal treated by HDSFE were all improved compared with SPI extracted from untreated soybean meal and white flakes. Molecular weight distribution analysis of SPI showed that after HDSFE treatment the peak with molecular weight about 504 kDa and 43.3 kDa disappeared and the peak with molecular weight about 669 kDa increased indicating protein aggregation. Gel electrophoresis showed that high molecular weight aggregates of protein have been formed by covalent bond. 相似文献
993.
994.
Edyta Janik Marcin Niemcewicz Marcin Podogrocki Joanna Saluk-Bijak Michal Bijak 《International journal of molecular sciences》2021,22(11)
COVID-19 is a respiratory disease caused by newly discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease at first was identified in the city of Wuhan, China in December 2019. Being a human infectious disease, it causes high fever, cough, breathing problems. In some cases it can be fatal, especially in people with comorbidities like heart or kidney problems and diabetes. The current COVID-19 treatment is based on symptomatic therapy, so finding an appropriate drug against COVID-19 remains an immediate and crucial target for the global scientific community. Two main processes are thought to be responsible for the COVID-19 pathogenesis. In the early stages of infection, disease is determined mainly by virus replication. In the later stages of infection, by an excessive immune/inflammatory response, leading to tissue damage. Therefore, the main treatment options are antiviral and immunomodulatory/anti-inflammatory agents. Many clinical trials have been conducted concerning the use of various drugs in COVID-19 therapy, and many are still ongoing. The majority of trials examine drug reposition (repurposing), which seems to be a good and effective option. Many drugs have been repurposed in COVID-19 therapy including remdesivir, favipiravir, tocilizumab and baricitinib. The aim of this review is to highlight (based on existing and accessible clinical evidence on ongoing trials) the current and available promising drugs for COVID-19 and outline their characteristics. 相似文献
995.
以三倍体毛白杨为研究对象,进行了常规硫酸盐法蒸煮。采用酶-弱酸解两段法分别从原料和KP纸浆中分离出原料木素和纸浆残余木素。采用酸析法从KP蒸煮黑液中分离出溶出木素样品,经过弱酸水解得到纯木素试样。通过凝胶渗透色谱分析(GPC),对所有试样分别进行了分子质量的检测,得出各种木素样品的分子质量及其分布,分析了木素溶出过程中的分子质量的变化。通过磷谱核磁共振31P-NMR技术得出木素结构谱图,对原料木素、纸浆残余木素和黑液溶出木素结构中各官能团进行了定量分析对比,研究了木素结构在KP蒸煮过程中的变化规律。 相似文献
996.
采用AS1.398和Alcalase两种蛋白酶,制备了水解度为10%~24%的大豆多肽,对其抗氧化性、ACE抑制活性和相对分子质量的分布进行了研究,结果表明采用AS1.398酶水解的DH为12%的产品抗氧化活性最高,添加量为6 mg/mL时使亚油酸的氧化诱导期延长2.92倍,其相对分子质量分布在1 000以上的组分较多;采用Alcalase酶水解的DH为14%的大豆多肽产品,ACE抑制活性最高,IC50为0.144 mg/mL,其相对分子质量分布大多在200~600之间. 相似文献
997.
以美国国家生物技术信息中心(NCBI)已公布的28株沙门菌(14个血清型)全基因组序列为研究对象,对前期研究获得的7个沙门菌属特异性检测靶点在不同血清型间的单核苷酸多态性进行比较分析,结果表明,S9和S69为碱基差异位点最多的两个靶点,具有沙门菌分子血清分型的潜在能力。随后,通过分析S9和S69在沙门菌不同血清型菌株中的差异位点,分别绘制两个血清分型靶点的差异位点表,从而获得了这两个靶点同时用于14个沙门菌血清型的快速分子血清分型的差异位点组合。在这些组合中,同一血清型具有相同的差异位点,不同血清型可以通过差异位点得以区分。最后,采集食品样品192份,用国标方法获得疑似沙门菌21株;利用血清分子分型靶点S9和S69进行快速分型,并同时用传统玻片凝集反应鉴定方法进行验证,两种方法鉴定结果的符合率为100%。鉴定结果为:21株沙门菌共包括4个不同血清型,其中肠炎沙门菌10株、鼠伤寒沙门菌7株、鸡沙门菌2株、纽波特沙门菌2株。基因组序列分析结果和分离株分型结果均表明,沙门菌特异分子检测靶点S9和S69相结合具备沙门菌的分子血清分型能力,以差异位点表为基础建立的血清分型方法有望替代传统的玻片凝集血清分型这一繁杂步骤,从而降低沙门菌血清鉴定的时间与成本,为聚合酶链式反应技术应用于沙门菌分子血清分型提供新思路。 相似文献
998.
用网络药理学方法进行逍遥丸治疗乳腺增生过程的机制研究.通过中药系统药理学数据库和分析平台(TCMSP)进行逍遥丸活性成分的搜集和筛选,将纳入的化合物成分通过TCMSP数据库进行成分的靶点预测;在GeneCards数据库,NCBI基因数据库以及OMIM数据库进行乳腺增生疾病靶点筛选;取药物靶点和疾病靶点作韦恩图,并利用共有靶点在String数据库中作PPI网络图,利用拓扑分析和MCODE聚类分析筛选核心靶点和核心基因;在cytoscape 3.8.0软件中进行关键活性成分的筛选;关键靶点使用String数据库进行GO分析和KEGG分析,将相关结果导入Cytoscape3.8.0绘制成分—疾病—通路—靶点网络图.结果表明,筛选得到逍遥丸各药活性成分及靶点,其中与乳腺增生相关的有169个靶点.STAT3、AKT1、MAPK1、JUN、MAPK3等20个靶点为该药治疗乳腺增生的关键靶点,HTR2A、IL2、TOP2A、PCNA、MMP1为该药治疗乳腺增生的核心基因.槲皮素(quercetin)、山奈酚(kaempferol)、叶黄素(luteolin)、柚皮素(naringenin)、甘草酮a(licochalcone a)、7-甲氧基-2-甲基异黄酮(7-Methoxy-2-methyl isoflavone)、芒柄花素(formononetin)、醋栗素(acacetin)等可能是逍遥丸治疗乳腺增生发挥作用的主要活性成分.GO富集分析总共富集到2328条生物过程,160项分子功能相关,47项细胞组成相关.通路富集分析显示与166条通路相关,涉及AGE-RAGE信号通路、TNF信号通路、IL-17信号通路、TH17细胞分化、流体剪切应力与动脉粥样硬化等信号通路.分子对接验证结果说明关键活性成分与核心靶点均对接良好. 相似文献
999.
1000.
Luis M. Montao Bettina Sommer Juan C. Gomez-Verjan Genaro S. Morales-Paoli Gema Lizbeth Ramírez-Salinas Hctor Solís-Chagoyn Zuly A. Sanchez-Florentino Eduardo Calixto Gloria E. Prez-Figueroa Rohan Carter Ruth Jaimez-Melgoza Bianca S. Romero-Martínez Edgar Flores-Soto 《International journal of molecular sciences》2022,23(8)
Theophylline (3-methyxanthine) is a historically prominent drug used to treat respiratory diseases, alone or in combination with other drugs. The rapid onset of the COVID-19 pandemic urged the development of effective pharmacological treatments to directly attack the development of new variants of the SARS-CoV-2 virus and possess a therapeutical battery of compounds that could improve the current management of the disease worldwide. In this context, theophylline, through bronchodilatory, immunomodulatory, and potentially antiviral mechanisms, is an interesting proposal as an adjuvant in the treatment of COVID-19 patients. Nevertheless, it is essential to understand how this compound could behave against such a disease, not only at a pharmacodynamic but also at a pharmacokinetic level. In this sense, the quickest approach in drug discovery is through different computational methods, either from network pharmacology or from quantitative systems pharmacology approaches. In the present review, we explore the possibility of using theophylline in the treatment of COVID-19 patients since it seems to be a relevant candidate by aiming at several immunological targets involved in the pathophysiology of the disease. Theophylline down-regulates the inflammatory processes activated by SARS-CoV-2 through various mechanisms, and herein, they are discussed by reviewing computational simulation studies and their different applications and effects. 相似文献