Selection of Taste Markers Related to Lactic Acid Bacteria Microflora Metabolism for Chinese Traditional Paocai: A Gas Chromatography–Mass Spectrometry-Based Metabolomics Approach

The production of rice-based beverages fermented by lactic acid bacteria (LAB) can increase the consumption of rice in the form of a dairy replacement. This study investigated volatile and nonvolatile components in rice fermented by 12 different LABs. Volatile compounds of fermented rice samples were analyzed using gas chromatography-mass spectrometry (GC-MS) combined with solid-phase microextraction (SPME), while nonvolatile compounds were determined using gas chromatography-time-of-flight/mass spectrometry (GC-TOF/MS) after derivatization. The 47 identified volatile compounds included acids, aldehydes, esters, furan derivatives, ketones, alcohols, benzene and benzene derivatives, hydrocarbons, and terpenes, while the 37 identified nonvolatile components included amino acids, organic acids, and carbohydrates. The profiles of volatile and nonvolatile components generally differed significantly between obligatorily homofermentative/facultatively heterofermentative LAB and obligatorily heterofermentative LAB. The rice sample fermented by Lactobacillus sakei (RTCL16) was clearly differentiated from the other samples on principal component analysis (PCA) plots. The results of PCA revealed that the rice samples fermented by LABs could be distinguished according to microbial strains.

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Fermentation Enhanced Biotransformation of Compounds in the Kernel of Chrysophyllum albidum

Molecules ◽

10.3390/molecules25246021 ◽

2020 ◽

Vol 25 (24) ◽

pp. 6021

Author(s):

Oluwatofunmi E. Odutayo ◽

Emmanuel A. Omonigbehin ◽

Tolulope D. Olawole ◽

Olubanke O. Ogunlana ◽

Israel S. Afolabi

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Cultures ◽

Gas Chromatography Mass Spectrometry ◽

Bile Salt Hydrolase ◽

Aqueous Extracts ◽

Acidic Environment ◽

African Star Apple

Chrysophyllum albidum Linn (African star apple) is a fruit with extensive nutritional and medicinal benefits. The fruit and kernel in the seed are both edible. Strains of lactic acid bacteria (LAB) were isolated from fermented seeds and assessed for probiotic characteristics. The extracts in both the unfermented and the fermented aqueous extracts from the kernels obtained from the seeds of C. albidum were subjected to analysis using the gas chromatography/mass spectrometry (GC-MS) method. This analysis identified the bioactive compounds present as possible substrate(s) for the associated organisms inducing the fermentation and the resultant biotransformed products formed. Three potential probiotic LAB strains identified as Lactococcus raffinolactis (ProbtA1), Lactococcus lactis (ProbtA2a), and Pediococcus pentosaceus (ProbtA2b) were isolated from the fermented C. albidum seeds. All strains were non hemolytic, which indicated their safety, Probt (A1, A2a, and A2b) grew in an acidic environment (pH 3.5) during the 48-h incubation time, and all three strains grew in 1% bile, and exhibited good hydrophobicity and auto-aggregation properties. Mucin binding proteins was not detected in any strain, and bile salt hydrolase was detected in all the strains. l-lactic acid (28.57%), norharman (5.07%), formyl 7E-hexadecenoate (1.73%), and indole (1.51%) were the four major constituents of the fermented kernel of the C. albidum, while 2,5-dimethylpyrazine (C1, 1.27%), 3,5-dihydroxy-6-methyl-2,3-dihydropyran-4-one (C2, 2.90%), indole (C3, 1.31%), norharman (C4, 3.01%), and methyl petroselinate (C5, 4.33%) were the five major constituents of the unfermented kernels. The isolated LAB are safe for consumption. The fermenting process metabolized C1, C2, and C5, which are possible starter cultures for the growth of probiotics. Fermentation is an essential tool for bioengineering molecules in foods into safe and health beneficial products.

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Exometabolites of some anaerobic microorganisms of human microflora

Biomeditsinskaya Khimiya ◽

10.18097/pbmc20115701095 ◽

2011 ◽

Vol 57 (1) ◽

pp. 95-105 ◽

Cited By ~ 7

Author(s):

N.V. Beloborodova ◽

I.T. Bairamov ◽

A.Yu. Olenin ◽

N.I. Fedotcheva

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Lactic Acid ◽

Gas Chromatography Mass Spectrometry ◽

Hydroxybutyric Acid ◽

Anaerobic Microorganisms ◽

Chromatography Mass Spectrometry ◽

Hydroxyglutaric Acid ◽

Anaerobic Microflora

Some exometabolites produced by basic representatives of human anaerobic microflora were investigated, detected by gas chromatography - mass spectrometry (GC-MS). In vitro besides lactic acid Bifidobacterium and Lactobacillus generate substantial amounts of phenyllactic and p-hydroxyphenyllactic acids. Clostridium produced 2-hydroxybutyric acid and to a lesser extent lactic and phenyllactic acids. In contrast to С. perfringens, C. sporogenes generates substantial amount of phenylpropionic and p-hydroxyphenylpropionic acids and less p-hydroxyphenyllactic acid. С. perfringens produced minor amounts of 2-hydroxyglutaric acid. Bacteroids are potent producers of succinic and fumaric acids; they also contribute to production of significant portion of lactic acid. E. lentum generate lactic, phenyllactic and succinic acids and form a characteristic only for ones (from studied microorganisms) 2-hydroxyhexanic and 2-hydroxy-3-methylbutyric acids.

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A methodological approach to the selection of liquid reagents for chemical ionization ion trap-gas chromatography mass spectrometry: A case study of GBL and 1,4-BD

International Journal of Mass Spectrometry ◽

10.1016/j.ijms.2015.07.018 ◽

2015 ◽

Vol 388 ◽

pp. 34-39 ◽

Cited By ~ 3

Author(s):

Luca Guandalini ◽

Giacomo Soldani ◽

Luca Rosi ◽

Luca Calamai ◽

Gianluca Bartolucci

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Chemical Ionization ◽

Ion Trap ◽

Methodological Approach ◽

Gas Chromatography Mass Spectrometry ◽

Chromatography Mass Spectrometry ◽

Selection Of

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Novel Applications for Biomaterials: The Case of Remediation of Wine Taints Using Poly-Lactic Acid Polymer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.749.70 ◽

2015 ◽

Vol 749 ◽

pp. 70-73 ◽

Cited By ~ 1

Author(s):

Andreea Botezatu ◽

Gary James Pickering

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Lactic Acid ◽

Solid Phase ◽

Alcoholic Beverage ◽

Film Surface ◽

Gas Chromatography Mass Spectrometry ◽

Poly Lactic Acid ◽

Chromatography Mass Spectrometry ◽

Before And After

Wine is the world’s oldest alcoholic beverage and the most consumed in at least 20 countries. However, taints detract from its quality and acceptance, significantly reducing the value of wine. In this study we investigated the capacity of a poly-lactic acid (PLA) biopolymer to reduce concentrations of four odorants responsible for tainting many red wines: isopropyl-methoxypyrazine (IPMP), isobutyl–methoxypyrazine (IBMP), 4-ethylphenol (4-EP) and 4-ethylguaiacol (4-EG). Red wine was spiked with either IPMP [20 ng/L] and IBMP [20 ng/L] (Study 1) or 4-EP [200 ug/L] and 4-EG [200 ug/L] (Study 2) and then treated with a PLA film [surface area 350 cm2/L]. Solid Phase Micro-Extraction Multi-Dimensional Gas Chromatography–Mass Spectrometry and Gas Chromatography-Mass Spectrometry were used to measure the methoxypyrazines and ethylphenols, respectively, both before and after treatment with PLA. Results showed significant reductions in all of the target odorants after 8hrs treatment: IPMP (51%), IBMP (26%), 4-EP (21%) and 4-EG (20%). Taken overall, the data suggest potential for the use of PLA in treating common wine faults, particularly ‘ladybug taint’, which is caused by elevated levels of IPMP.

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Identification of a synthetic cannabinoid 5F-NPB-22 (indazole analog 5F-PB-22) by gas chromatography/mass spectrometry (GC/MS) method

Issues of Forensic Science ◽

10.34836/pk.2016.293.1 ◽

2016 ◽

Vol 293 ◽

pp. 56-67

Author(s):

Robert Bachliński ◽

◽

Agnieszka Mroczek ◽

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Direct Injection ◽

Ion Source ◽

Synthetic Cannabinoid ◽

Gas Chromatography Mass Spectrometry ◽

Extraction Solvent ◽

Chromatography Mass Spectrometry ◽

Selection Of

This article presents the problem of transesterification of a synthetic cannabinoid 5F-NPB-22 and other structurally related indazole and indole-based compounds, such as NPB-22, 5F-PB-22, BB-22 and PB-22, caused by methanol – a solvent commonly applied in gas chromatography/mass spectrometry (GC/MS) analysis. The above process can result in drawing incorrect conclusions about the composition of analyzed product, due to the formation of ester compounds, which mainly affects the reliability of results. In the present study, in addition to the mixture of methanol and toluene, as well toluene alone was used to evaluate the effect of both these solvents on the results obtained with GC/MS. The quality of analyses was additionally confirmed by quadrupole-time-of-flight (Q-TOF) mass spectrometry with direct injection of sample into the ion source. The final results indicate that in the case of transesterification-sensitive compounds, the selection of an adequate extraction-solvent is of major importance. It is recommended to use toluene and exclude transesterification-supporting solvents such as low molecular weight alcohols (methanol.ethanol). Moreover, a prompt analysis of the extracted substances should be ensured in order to eliminate their potential esterification.

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