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烟酰化壳寡糖季铵盐的制备及抑菌活性研究 被引量:3
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作者 林琮皓 袁玉婷 +2 位作者 谭文强 郭占勇 姜爱莉 《海洋科学》 CAS CSCD 北大核心 2024年第1期44-55,共12页
海洋生物体内蕴含着丰富的天然活性物质,许多都具有抑菌活性,据此研制新型海洋生物源抑菌药物,是海洋生物产业中的一个新领域,也是新型抑菌药物研发的重要途径。壳聚糖是来自海洋中虾蟹等甲壳类动物外壳的甲壳素的脱乙酰产物,壳寡糖是... 海洋生物体内蕴含着丰富的天然活性物质,许多都具有抑菌活性,据此研制新型海洋生物源抑菌药物,是海洋生物产业中的一个新领域,也是新型抑菌药物研发的重要途径。壳聚糖是来自海洋中虾蟹等甲壳类动物外壳的甲壳素的脱乙酰产物,壳寡糖是壳聚糖的降解产物,具有比壳聚糖更好的水溶性和生物活性,在食品和生物医药等领域具有更广阔的应用前景。为了提高壳寡糖的抑菌活性,本研究以壳寡糖和烟酸为原料、N, N-羰基二咪唑为催化剂合成了壳寡糖烟酸接枝衍生物,并与不同链长的溴代烷烃亲核反应得到其阳离子化衍生物。壳寡糖及其衍生物的化学结构通过红外光谱(FTIR)和核磁共振波谱(NMR)进行分析表征,壳寡糖及其衍生物对2种海洋致病细菌和3种植物致病真菌的体外抑菌能力分别采用肉汤稀释法和菌丝生长速率法进行研究和评估。结果表明,与壳寡糖相比,合成的终产物对致病菌的抑制能力得到了极大增强,其中含有己基的烟酰化壳寡糖季铵盐表现出最强的抑制海洋致病细菌活性(MIC=0.125mg/mL、MBC=0.25mg/mL),并且该化合物表现出较强的抗真菌活性,在1.0 mg/mL时,对灰葡萄孢菌和围小丛壳的抑制率分别为65.7%和51.5%。这些结果表明,含直链烷烃的烟酰化壳寡糖季铵盐具有较强的抑菌活性,在食品、生物医药等行业具有较大的应用潜力。 展开更多
关键词 壳寡糖 烟酰化反应 阳离子化 直链烷基 抑菌活性
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A new approach to inferring the threshold range for quality control of ocean T/S profiles based on probability distribution of historical data
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作者 lin conghao Wang Huizan +3 位作者 Bao Senliang Liu Zenghong Yan Hengqian An Yuzhu 《Acta Oceanologica Sinica》 2025年第10期227-243,共17页
The Argo program measures temperature and salinity in the upper ocean(0–2000 m).These observations are critical for weather/climate studies,ocean circulation analysis,and sea-level monitoring.To address the limitatio... The Argo program measures temperature and salinity in the upper ocean(0–2000 m).These observations are critical for weather/climate studies,ocean circulation analysis,and sea-level monitoring.To address the limitations of traditional thresholds in Argo data quality control(QC),this study proposes a novel probability distribution-based inference method(PDIM)for temperature-salinity threshold inference.By integrating historical observations with climatological data,the method utilizes historical data corresponding to latitude and longitude grids,calculates temperature/salinity frequency distributions for each depth,and determines“zero probability”boundaries through combined frequency distribution and climatology data.Then a probability distribution model is established to detect outliers automatically based on the features in the probability density function,which eliminates the traditional dependence on the normal distribution hypothesis.When applied to global Argo datasets from China Argo Real-time Data Center(CARDC),PDIM successfully identifies suspicious profiles and sensor drifts with high reliability,achieving a low false positive rate(0.55%for temperature,0.18%for salinity)while maintaining competitive true positive rate(28.29%for temperature,55.15%for salinity).This method is expected to improve the reliability of Argo data QC and has important significance for Argo QC. 展开更多
关键词 Argo float histrical observation quality control probability distribution
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