为实现南极磷虾(Euphausia superba)品质的快速评定,本研究将近红外光谱技术(Near infrared spectroscopy,NIRS)与偏最小二乘法(Partial least squares,PLS)相结合,构建用于快速预测磷虾体内非蛋白氮(Non-protein nitrogen,NPN)含量和...为实现南极磷虾(Euphausia superba)品质的快速评定,本研究将近红外光谱技术(Near infrared spectroscopy,NIRS)与偏最小二乘法(Partial least squares,PLS)相结合,构建用于快速预测磷虾体内非蛋白氮(Non-protein nitrogen,NPN)含量和挥发性盐基氮(Total volatile base nitrogen,TVB-N)含量的近红外定量分析模型。采集近红外光谱后,通过比较决定系数(Coefficient of determination,R^(2))、校正标准偏差(Root mean square error of calibration,RMSEC)、预测标准偏差(Root mean square error of prediction,RMSEP)等模型的评价参数,选取近红外光谱定量分析模型的最佳预处理方式、特征光谱范围以及主因子数。结果显示,NPN含量模型的最佳预处理方法为多元散射校正(Multiplicative signal correction,MSC),其特征光谱范围为8887.1~7774.2 cm-1;TVB-N含量模型则采用MSC与卷积平滑(Savitzky-Golay smoothing,SG)相结合的方式进行预处理,建模范围为全波段。两个定量模型的主因子数均为5。经模型的优化与外部验证,最终构建的PLS最优模型如下:NPN含量近红外定量分析模型的R^(2)为0.9384,RMSEC为0.279,RMSEP为0.443;TVB-N含量近红外定量分析模型的R^(2)为0.8685,RMSEC为3.800,RMSEP为4.070。研究结果表明,两个模型均具有良好的预测精度(R^(2)>0.85)和稳定性,其中NPN定量分析模型的预测能力优于TVB-N定量分析模型。综上,本研究基于NIRS与PLS构建的定量分析模型能够有效预测南极磷虾体内的NPN和TVB-N含量,为南极磷虾的品质评价提供了可靠的技术支持,满足快速评定的实际应用需求。展开更多
目的建立氟化物核糖开关转录反应体系以及成簇的规律间隔的短回文重复序列/Cas12a蛋白(clustered regularly interspaced short palindromic repeats-associated protein 12a,CRISPR/Cas12a)检测氟含量的方法。方法本研究利用氟化物核...目的建立氟化物核糖开关转录反应体系以及成簇的规律间隔的短回文重复序列/Cas12a蛋白(clustered regularly interspaced short palindromic repeats-associated protein 12a,CRISPR/Cas12a)检测氟含量的方法。方法本研究利用氟化物核糖开关在有氟或无氟下转录全长或非全长RNA并与CRISPR/Cas12a系统相结合,通过荧光法读取实验结果。对优化的CRISPR/Cas12a检测体系进行选择性和干扰性分析实验,并用于南极磷虾氟含量的检测。结果本研究成功建立了基于氟化物核糖开关转录反应体系CRISPR/Cas12a荧光检测方法,可在1.5 h内完成对样品的检测,检测结果与国家标准方法氟离子选择电极法基本保持一致。结论本研究建立的基于氟化物核糖开关转录反应和CRISPR/Cas12a的南极磷虾中氟含量检测方法具有高特异性和准确性,在氟含量的检测方面具有应用价值。展开更多
With the improvement of living standards and the shift in societal consumption attitudes,consumers demand for the quality of aquatic products is increasingly stringent.Freshness and quality have become primary factors...With the improvement of living standards and the shift in societal consumption attitudes,consumers demand for the quality of aquatic products is increasingly stringent.Freshness and quality have become primary factors determining consumers purchasing decisions.However,due to the high moisture content,active endogenous enzymes,and rich nutrients in aquatic products,both fresh and processed products are highly susceptible to quality deterioration during procurement,distribution,and storage,which leads to a significant decline in sensory quality and nutritional value,while also compromising safety.Today,the consumption of high-quality aquatic products has become a prevailing trend.This paper reviewed the methods for freshness evaluation and quality grading of aquatic products in terms of sensory and nutritional aspects,aiming to support the market circulation principle of"higher price for better quality"and"price based on quality",and better meeting consumer demands.Therefore,it is imperative to enhance the analysis and evaluation of aquatic product quality and to continuously refine assessment systems and methods,which is crucial for promoting industry transformation and fostering a healthy market-consumer economic cycle.展开更多
目的建立以生物胺(biogenic amine,BA)为标志物冷链鱼虾新鲜度评价方法。方法应用液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS),通过观测不同贮藏条件下冷冻带鱼、冰鲜鲈鱼和冷冻虾仁中BA的时间-含...目的建立以生物胺(biogenic amine,BA)为标志物冷链鱼虾新鲜度评价方法。方法应用液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS),通过观测不同贮藏条件下冷冻带鱼、冰鲜鲈鱼和冷冻虾仁中BA的时间-含量动态,分别将组胺(histamine,HIS)、色胺(tryptamine,TRY)、腐胺(putrescine,PUT)、尸胺(cadaverine,CAD)和三甲胺(trimethylamine,TMA)含量之和与精胺(spermine,SPM)、亚精胺(spermidine,SPD)含量之和的比值定义为腐败指数,将氧化三甲胺(trimethylamine oxide,TMAO)含量与SPD、SPM含量之和的比值定义为鲜味指数,用于冷链鱼虾的新鲜度评价;实验同时进行了感官评价。结果腐败指数评价方法与感官评价方法对3种代表性样品新鲜度评级结果的一致程度为94.4%;鲜味指数则提供了鲜味物质的存留信息,是腐败指数的重要补充。结论以BA为标志物,通过定义腐败指数和鲜味指数的新鲜度评价方法,为相关产品新鲜度的评价和质量监测提供了更为全面、客观的依据。展开更多
文摘为实现南极磷虾(Euphausia superba)品质的快速评定,本研究将近红外光谱技术(Near infrared spectroscopy,NIRS)与偏最小二乘法(Partial least squares,PLS)相结合,构建用于快速预测磷虾体内非蛋白氮(Non-protein nitrogen,NPN)含量和挥发性盐基氮(Total volatile base nitrogen,TVB-N)含量的近红外定量分析模型。采集近红外光谱后,通过比较决定系数(Coefficient of determination,R^(2))、校正标准偏差(Root mean square error of calibration,RMSEC)、预测标准偏差(Root mean square error of prediction,RMSEP)等模型的评价参数,选取近红外光谱定量分析模型的最佳预处理方式、特征光谱范围以及主因子数。结果显示,NPN含量模型的最佳预处理方法为多元散射校正(Multiplicative signal correction,MSC),其特征光谱范围为8887.1~7774.2 cm-1;TVB-N含量模型则采用MSC与卷积平滑(Savitzky-Golay smoothing,SG)相结合的方式进行预处理,建模范围为全波段。两个定量模型的主因子数均为5。经模型的优化与外部验证,最终构建的PLS最优模型如下:NPN含量近红外定量分析模型的R^(2)为0.9384,RMSEC为0.279,RMSEP为0.443;TVB-N含量近红外定量分析模型的R^(2)为0.8685,RMSEC为3.800,RMSEP为4.070。研究结果表明,两个模型均具有良好的预测精度(R^(2)>0.85)和稳定性,其中NPN定量分析模型的预测能力优于TVB-N定量分析模型。综上,本研究基于NIRS与PLS构建的定量分析模型能够有效预测南极磷虾体内的NPN和TVB-N含量,为南极磷虾的品质评价提供了可靠的技术支持,满足快速评定的实际应用需求。
文摘目的建立氟化物核糖开关转录反应体系以及成簇的规律间隔的短回文重复序列/Cas12a蛋白(clustered regularly interspaced short palindromic repeats-associated protein 12a,CRISPR/Cas12a)检测氟含量的方法。方法本研究利用氟化物核糖开关在有氟或无氟下转录全长或非全长RNA并与CRISPR/Cas12a系统相结合,通过荧光法读取实验结果。对优化的CRISPR/Cas12a检测体系进行选择性和干扰性分析实验,并用于南极磷虾氟含量的检测。结果本研究成功建立了基于氟化物核糖开关转录反应体系CRISPR/Cas12a荧光检测方法,可在1.5 h内完成对样品的检测,检测结果与国家标准方法氟离子选择电极法基本保持一致。结论本研究建立的基于氟化物核糖开关转录反应和CRISPR/Cas12a的南极磷虾中氟含量检测方法具有高特异性和准确性,在氟含量的检测方面具有应用价值。
基金Supported by Tangshan Talent Funding Project in 2025(B202304018).
文摘With the improvement of living standards and the shift in societal consumption attitudes,consumers demand for the quality of aquatic products is increasingly stringent.Freshness and quality have become primary factors determining consumers purchasing decisions.However,due to the high moisture content,active endogenous enzymes,and rich nutrients in aquatic products,both fresh and processed products are highly susceptible to quality deterioration during procurement,distribution,and storage,which leads to a significant decline in sensory quality and nutritional value,while also compromising safety.Today,the consumption of high-quality aquatic products has become a prevailing trend.This paper reviewed the methods for freshness evaluation and quality grading of aquatic products in terms of sensory and nutritional aspects,aiming to support the market circulation principle of"higher price for better quality"and"price based on quality",and better meeting consumer demands.Therefore,it is imperative to enhance the analysis and evaluation of aquatic product quality and to continuously refine assessment systems and methods,which is crucial for promoting industry transformation and fostering a healthy market-consumer economic cycle.
