scholarly journals Studies on the method for determination of some polysaccharide food additives by fourier transform infrared spectrum (FTIR)

2020 ◽  
Vol 3 (1) ◽  
pp. 46-53
Author(s):  
Huyen Trang Luu Thi ◽  
Thuy Le Thi ◽  
Giang Tran Hoang ◽  
Trang Vu Thi ◽  
Minh Loi Nguyen Thi ◽  
...  
Keyword(s):  
Infrared Spectrum ◽  
Xanthan Gum ◽  
Near Infrared ◽  
Guar Gum ◽  
Food Additives ◽  
Volume Ratio ◽  
Food Additive ◽  
Experimental Conditions ◽  
Mixture Samples

In this study, the simultaneous quantitative analysis of samples using multivarite linear regression based on near infrared spectrum has been developed. The model of partial least squares (PLS) matrix with seven value vectors is built with a standard matrix of samples (24 samples containing four analytes together with a total number of excipients) are applied for individual and/or simultaneous determination of guar gum, CMC, carrageenan, xanthan gum in real samples. A matrix of test samples including 10 samples created by fouranalytes to assess the accuracy of the PLS model. The results indicated that the relative error varied from 1.1 to 15%. The optimum experimental conditions were: spectral region: 1700 - 900 cm-1; volume ratio of sample/KBr: 2/98 (w/w); weight per capsule was 15 mg. The method was applied to identify four analytes in 15 material samples and food additive mixture samples.

scholarly journals The Food Additive Xanthan Gum Drives Adaptation of the Human Gut Microbiota

2021 ◽  
Author(s):  
Matthew P. Ostrowski ◽  
Sabina Leanti La Rosa ◽  
Benoit J. Kunath ◽  
Andrew Robertson ◽  
Gabriel Pereira ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Xanthan Gum ◽  
Enrichment Culture ◽  
Food Additives ◽  
Food Additive ◽  
Glycoside Hydrolase Family ◽  
Human Gut ◽  
High Molecular Weight Polymer ◽  
Molecular Weight Polymer ◽  
Uncultured Bacterium

SummaryThe diets of industrialized countries reflect the increasing use of processed foods, often with the introduction of novel food additives. Xanthan gum is a complex polysaccharide with unique rheological properties that have established its use as a widespread stabilizer and thickening agent1. However, little is known about its direct interaction with the gut microbiota, which plays a central role in digestion of other, chemically-distinct dietary fiber polysaccharides. Here, we show that the ability to digest xanthan gum is surprisingly common in industrialized human gut microbiomes and appears to be contingent on the activity of a single bacterium that is a member of an uncultured bacterial genus in the family Ruminococcaceae. We used a combination of enrichment culture, multi-omics, and recombinant enzyme studies to identify and characterize a complete pathway in this uncultured bacterium for the degradation of xanthan gum. Our data reveal that this keystone degrader cleaves the xanthan gum backbone with a novel glycoside hydrolase family 5 (GH5) enzyme before processing the released oligosaccharides using additional enzymes. Surprisingly, some individuals harbor a Bacteroides species that is capable of consuming oligosaccharide products generated by the keystone Ruminococcaceae or a purified form of the GH5 enzyme. This Bacteroides symbiont is equipped with its own distinct enzymatic pathway to cross-feed on xanthan gum breakdown products, which still harbor the native linkage complexity in xanthan gum, but it cannot directly degrade the high molecular weight polymer. Thus, the introduction of a common food additive into the human diet in the past 50 years has promoted the establishment of a food chain involving at least two members of different phyla of gut bacteria.

scholarly journals Dipsticks with Reflectometric Readout of an NIR Dye for Determination of Biogenic Amines

Chemosensors ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 99
Author(s):  
Sarah N. Mobarez ◽  
Nongnoot Wongkaew ◽  
Marcel Simsek ◽  
Antje J. Baeumner ◽  
Axel Duerkop
Keyword(s):  
Biogenic Amines ◽  
Indium Tin Oxide ◽  
Near Infrared ◽  
High Surface ◽  
High Surface Area ◽  
Volume Ratio ◽  
Sample Pretreatment ◽  
Primary Amines ◽  
Nir Dye

Electrospun nanofibers (ENFs) are remarkable analytical tools for quantitative analysis since they are inexpensive, easily produced in uniform homogenous mats, and provide a high surface area-to-volume ratio. Taking advantage of these characteristics, a near-infrared (NIR)-dye was doped as chemosensor into ENFs of about 500 nm in diameter electrospun into 50 µm thick mats on indium tin oxide (ITO) supports. The mats were made of cellulose acetate (CA) and used as a sensor layer on optical dipsticks for the determination of biogenic amines (BAs) in food. The ENFs contained the chromogenic amine-reactive chameleon dye S0378 which is green and turns blue upon formation of a dye-BA conjugate. This SN1-reaction of the S0378 dye with various BAs was monitored by reflectance measurements at 635 nm where the intrinsic absorption of biological material is low. The difference of the reflectance before and after the reaction is proportional to BA levels from 0.04–1 mM. The LODs are in the range from 0.03–0.09 mM, concentrations that can induce food poisoning but are not recognized by the human nose. The calibration plots of histamine, putrescine, spermidine, and tyramine are very similar and suggesting the use of the dipsticks to monitor the total sample BA content. Furthermore, the dipsticks are selective to primary amines (both mono- and diamines) and show low interference towards most nucleophiles. A minute interference of proteins in real samples can be overcome by appropriate sample pretreatment. Hence, the ageing of seafood samples could be monitored via their total BA content which rose up to 21.7 ± 3.2 µmol/g over six days of storage. This demonstrates that optically doped NFs represent viable sensor and transducer materials for food analysis with dipsticks.

scholarly journals Simultaneous determination of vanillin, ethyl vanillin, menthol, amyl acetate, citral in food additives by gas chromatography tamdem mass spectrometry (GC/MS)

2018 ◽  
Vol 1 (1) ◽  
pp. 25-28
Author(s):  
Ngan Le Viet ◽  
Kim Oanh Vu Thi ◽  
Trang Vu Thi ◽  
Huyen Trang Luu Thi ◽  
◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Sample Preparation ◽  
Analytical Method ◽  
Food Additives ◽  
Food Additive ◽  
Amyl Acetate ◽  
Flavor Compound ◽  
Ethyl Vanillin

The objective of this study to determine sample preparation and analysis vanillin, ethyl vanillin, menthol, amyl acetate and citral in the food additives using gas chromatography mass tandem spectrometry. The substances were extracted from the matrices with acetonitrile at 30°C for 15 minutes, determined by GC-MS using DB5-MS column (30m x 0.25mm x 0.25μm) for separation, the MS/MS detector. The calibration curves had concentration of 0.05 to 20 μg/mL, the method had the recovery of from 95.0% to 105%, the repeatability of from 1.92 to 4.04%. Applying the analytical method on 15 flavor food additive samples which were collected from markets showed most of the flavor additives contain more than one flavor compound in composition.

Molar Absorptivity Measurements in Absorbing Solvents: Impact on Solvent Absorptivity Values

2016 ◽  
Vol 71 (3) ◽  
pp. 446-455
Author(s):  
Ariel Bohman ◽  
Mark A. Arnold
Keyword(s):  
Infrared Spectrum ◽  
Path Length ◽  
Near Infrared ◽  
Light Attenuation ◽  
Systematic Errors ◽  
Molar Absorptivity ◽  
Experimental Conditions ◽  
Path Length Difference ◽  
Absolute Measurements ◽  
Near Infrared Spectrum

Molar absorptivity is a fundamental molecular property that quantifies absorption strength as a function of wavelength. Absolute measurements of molar absorptivity demand accounting for all mechanisms of light attenuation, including reflective losses at interfaces associated with the sample. Ideally, such measurements are performed in nonabsorbing solvents and reflective losses can be determined in a straightforward manner from Fresnel equations or effectively accounted for by path length difference methods. At near-infrared wavelengths, however, many solvents, including water, are absorbing which complicates the quantification of reflective losses. Here, generalized equations are developed for calculating absolute molar absorptivities of neat liquids wherein the dependency of reflective loss on absorption properties of the liquid are considered explicitly. The resulting equations are used to characterize sensitivity of absolute molar absorptivity measurements for solvents to the absorption strength of the solvent as well as the path length of the measurement. Methods are derived from these equations to properly account for reflective losses in general and the effectiveness of these methods is demonstrated for absolute molar absorptivity measurements for water over the combination region (5000–4000 cm−1) of the near-infrared spectrum. Results indicate that ignoring solvent absorption effects can incorporate wide ranging systematic errors depending upon experimental conditions. As an example, systematic errors range from 0 to 10% for common conditions used in the measurement of absolute molar absorptivity of water over the combination region of the near-infrared spectrum.

Determination of Magnolol and Honokiol in Mangnolia Officinalis by Near-Infrared Spectroscopy Rapidly

2013 ◽  
Vol 807-809 ◽  
pp. 2092-2096
Author(s):  
Jing Wei Lei ◽  
Hai Yan Gong ◽  
Yan Li Guo ◽  
Cai Xia Xie ◽  
Xiao Yan Duan ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Infrared Spectrum ◽  
Near Infrared ◽  
Cross Validation ◽  
Quantitative Model ◽  
Calibration Model ◽  
Mean Square ◽  
Validation Set ◽  
Near Infrared Spectrum

In this paper, Near-infrared spectrum technology was applied for fast determining the content of magnolol and honokiol in Mangnolia officinalis. 105 samples of Mangnolia officinalis from xx pharmaceutical factories were divided into a calibration set (79 samples) and a validation set (26 samples). The near infrared spectrum of samples were collected, while take the HPLC value as a reference, Use the partial least squares (PLS) to establish the quantitative model of Magnolol and Honokiol. The correlation coefficient of calibration (R2), the root-mean-square error of calibration (RMSEC) and the root-mean-squareerror of cross-validation (RMSECV) of the calibration model were 0.9813, 0.0833, 0.2518; the recovery rate of prediction of the validation was 99.99%.The method is uncomplicated and result is accurate, which could measure the content of Mangnolia officinalis in bulk and fast, save costs and improve efficiency.

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