Gas Chromatography/Principal Component Similarity System for Detection ofE. coliandS. aureusContaminating Salmon and Hamburger

1999 ◽  
Vol 47 (2) ◽  
pp. 576-583 ◽  
Author(s):  
S. Nakai ◽  
Z. H. Wang ◽  
J. Dou ◽  
S. Nakamura ◽  
M. Ogawa ◽  
...  
Metabolites ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 265
Author(s):  
Ruchi Sharma ◽  
Wenzhe Zang ◽  
Menglian Zhou ◽  
Nicole Schafer ◽  
Lesa A. Begley ◽  
...  

Asthma is heterogeneous but accessible biomarkers to distinguish relevant phenotypes remain lacking, particularly in non-Type 2 (T2)-high asthma. Moreover, common clinical characteristics in both T2-high and T2-low asthma (e.g., atopy, obesity, inhaled steroid use) may confound interpretation of putative biomarkers and of underlying biology. This study aimed to identify volatile organic compounds (VOCs) in exhaled breath that distinguish not only asthmatic and non-asthmatic subjects, but also atopic non-asthmatic controls and also by variables that reflect clinical differences among asthmatic adults. A total of 73 participants (30 asthma, eight atopic non-asthma, and 35 non-asthma/non-atopic subjects) were recruited for this pilot study. A total of 79 breath samples were analyzed in real-time using an automated portable gas chromatography (GC) device developed in-house. GC-mass spectrometry was also used to identify the VOCs in breath. Machine learning, linear discriminant analysis, and principal component analysis were used to identify the biomarkers. Our results show that the portable GC was able to complete breath analysis in 30 min. A set of nine biomarkers distinguished asthma and non-asthma/non-atopic subjects, while sets of two and of four biomarkers, respectively, further distinguished asthmatic from atopic controls, and between atopic and non-atopic controls. Additional unique biomarkers were identified that discriminate subjects by blood eosinophil levels, obese status, inhaled corticosteroid treatment, and also acute upper respiratory illnesses within asthmatic groups. Our work demonstrates that breath VOC profiling can be a clinically accessible tool for asthma diagnosis and phenotyping. A portable GC system is a viable option for rapid assessment in asthma.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1180
Author(s):  
Xiaoyu Yin ◽  
Qian Chen ◽  
Qian Liu ◽  
Yan Wang ◽  
Baohua Kong

Smoking is mainly used to impart desirable flavour, colour and texture to the products. Various food smoking methods can be divided into traditional and industrial methods. The influences of three different smoking methods, including traditional smouldering smoke (TSS), industrial smouldering smoke (ISS) and industrial liquid smoke (ILS), on quality characteristics, sensory attributes and flavour profiles of Harbin red sausages were studied. The smoking methods had significant effects on the moisture content (55.74–61.72 g/100 g), L*-value (53.85–57.61), a*-value (11.97–13.15), b*-value (12.19–12.92), hardness (24.25–29.17 N) and chewiness (13.42–17.32). A total of 86 volatile compounds were identified by headspace solid phase microextraction combined with comprehensive two-dimensional gas chromatography mass spectrometry (GC × GC-qMS). Among them, phenolic compounds were the most abundant compounds in the all sausages. Compared with sausages smoked with smouldering smoke, the ILS sausages showed the highest content of volatile compounds, especially phenols, alcohols, aldehydes and ketones. Principal component analysis showed that the sausages smoked with different methods had a good separation based on the quality characteristics and GC × GC-qMS data. These results will facilitate optimising the smoking methods in the industrial production of smoked meat products.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Anis Chikhoune ◽  
Fatiha Bedjou ◽  
Sabrina Oubouzid ◽  
Rosa Boukefoussa ◽  
Bilal Bechri ◽  
...  

Interesterification becomes a very powerful tool in food industry. A blend of coconut oil and palm stearin is enzymatically interesterified by lipase (EC 3.1.1.3) in an aquarium reactor. The interesterified blend obtained is then incorporated in madeleines, mini croissants, and mini rolls. Physicochemical parameters’ assessment for molasses used is in good agreement with the international standards. Fatty acid composition of the interesterified blend and sugar content of molasses were assessed by gas chromatography (GC) and high performance liquid chromatography (HPLC). A sensory evaluation of the madeleines, mini croissants, and buns has been carried out by untrained tasters, with a statistical analysis by a principal component analysis (PCA). Chromatographic characterization by Gas Chromatography revealed fatty acids, ranging from C6: 0 to C22: 0. Liquid sugar’s content by high performance liquid chromatography revealed three main sugars: sucrose, glucose, and fructose. Results of the sensory analysis showed the good quality of the prepared products.


2016 ◽  
Vol 78 (2) ◽  
Author(s):  
Nurrulhidayah Ahmad Fadzlillah ◽  
Abdul Rohman ◽  
Arieff Salleh Rosman ◽  
Farahwahida Mohd Yusof ◽  
Amin Ismail ◽  
...  

Butter is high priced product; as a consequence, butter can be subjected for adulteration with low price components such as lard. The presence of lard in any products is not allowed for Muslim and Jewish, therefore, its presence must be identified. Gas chromatography-mass spectrometry was successfully used to detect and discriminate butter from adulterated with lard. Results were presented in the form of chromatogram. Principal component analysis (PCA) was used to interpret the data and provided a good grouping of samples with 55.8% of the variation accounted for by PC 1 and 21.5% were accounted for by PC 2. All the lard containing samples formed a separate group from the samples that were free of lard. This method can be developed into a rapid method for detecting the presence of lard in food samples for Halal authentication.


2013 ◽  
Vol 8 (1) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Laura Guerra-Boone ◽  
Rocío Álvarez-Román ◽  
Ricardo Salazar-Aranda ◽  
Anabel Torres-Cirio ◽  
Verónica Mayela Rivas-Galindo ◽  
...  

The essential oils from Magnolia grandiflora and Chrysactinia mexicana leaves, and from Schinus molle leaves and fruit, were characterized by gas chromatography/flame-ionization detection and gas chromatography/mass spectrometry. Twenty-eight compounds from M. grandiflora leaves were identified (representing 93.6% of the total area of the gas chromatogram), with the major component being bornyl acetate (20.9%). Colorless and yellow oils were obtained from the C. mexicana leaves with 18 (86.7%) and 11 (100%) compounds identified, respectively. In both fractions, the principal component was sylvestrene (36.8% and 41.1%, respectively). The essential oils of S. molle leaves and fruit were each separated into colorless and yellow fractions, in which 14 (98.2) and 20 (99.8%) compounds were identified. The main component was α-phellandrene in all fractions (between 32.8% and 45.0%). The M. grandiflora oil displayed antifungal activity against five dermatophyte strains. The oils from S. molle and M. grandiflora leaves had antimicrobial activity against Staphylococcus aureus and Streptococcus pyogenes, which cause skin infections that potentially may lead to sepsis. However, the antioxidant activities of all oils were small (half maximal effective concentration values >250 μg/mL).


2001 ◽  
Vol 2001 (1) ◽  
pp. 97-107
Author(s):  
Gary Moffatf

ABSTRACT High resolution gas chromatography (GC) and gas chromatography in conjunction with mass spectrometry (GCMS) were used as fingerprinting techniques in this study to link oil spilled from the New Carissa to oil taken from oil impacted locations. Analyses included normal and isoprenoid alkanes, hopanes, and steranes, as well as a range of polynuclear aromatic hydrocarbons (PAHS). The oil spilled from the New Carissa was initially thought to be limited to bunker oils. Therefore, chromatograms of these samples and selected ion monitoring (SIM) chromatograms of the components and their combinations were compared, and obvious mismatches were rejected. Initial comparisons seemed simple; however, as with the spill response itself, factors that most often are insignificant began to affect the chemical analyses. Complications and technical challenges using conventional fingerprinting methods arose for several reasons. Likely reasons are (1) the spilled oil weathered on continued exposure to environmental conditions; (2) burning could cause changes to the chemical fingerprint; and (3) potential inhomogeneity of the spill because of multiple fuel sources in five fuel tanks at the bottom of the vessel. The PAH fingerprint had limited resistance to weathering. Therefore, the hopane fingerprint was selected for its resistance to weathering and potential screening power. Preburn and postburn New Carissa oil was characterized using principal component analysis (PCA) to determine if new and seemingly unrelated tarballs could be derived from the New Carissa spill. Response personnel will benefit from the lessons learned about potential complications of oil identification and subsequent determination of origin.


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