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Keywords = on-line HPLC-GC

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18 pages, 1385 KB  
Article
Detection of Adulterants in Herbal Weight Loss Supplements
by Oana Ramona Cătălina Gheorghiu, Anne Marie Ciobanu, Claudia Maria Guțu, George-Mădălin Dănilă, Gabriela Viorela Nițescu, Ștefan Rohnean and Daniela Luiza Baconi
J. Mind Med. Sci. 2025, 12(1), 23; https://doi.org/10.3390/jmms12010023 - 25 Apr 2025
Cited by 2 | Viewed by 5616
Abstract
The growing popularity and consumption of herbal slimming supplements can be attributed to their perception as natural products that lack side effects. However, the composition and ingredient quality listed on their labels often undergo insufficient control. As a result, some manufacturers add undeclared [...] Read more.
The growing popularity and consumption of herbal slimming supplements can be attributed to their perception as natural products that lack side effects. However, the composition and ingredient quality listed on their labels often undergo insufficient control. As a result, some manufacturers add undeclared synthetic pharmaceuticals to enhance weight loss effects. The synthetic adulterants, particularly the anorectic stimulants, have been associated with increased risks of cardiovascular adverse effects, posing significant health risks to consumers. This study aimed to analyze various weight loss supplements marketed as “natural” products to detect possible adulterants. A new high-performance thin-layer chromatography (HPTLC) method was used for initial screening, while gas chromatography coupled with mass spectrometry (GC–MS) served as a confirmation tool. Additionally, high-performance liquid chromatography (HPLC) was employed to analyze phenolphthalein. A total of 34 supplements acquired online or from specialty stores were analyzed. It was found that most of them contain caffeine from herbal ingredients included in the products’ formulation. Some products list the added caffeine, but the measured levels significantly exceeded the labeled values. The most commonly detected adulterants were sibutramine and phenolphthalein. These results highlighted the inadequacies and inconsistencies in labeling, as all herbal supplements were declared “natural” despite containing adulterants. Furthermore, they highlighted the suitability of the HPTLC method as an effective and cost-effective screening tool for detecting adulterants in dietary supplements. Full article
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14 pages, 2873 KB  
Article
Endogenous n-Alkanes in Vegetable Oils: Validation of a Rapid Offline SPE-GC-FID Method, Comparison with Online LC-GC-FID and Potential for Olive Oil Quality Control
by Ana Srbinovska, Paolo Lucci, Chiara Conchione, Laura Barp and Sabrina Moret
Molecules 2023, 28(11), 4393; https://doi.org/10.3390/molecules28114393 - 28 May 2023
Cited by 2 | Viewed by 2230
Abstract
The potential of endogenous n-alkane profiling for the assessment of extra virgin olive oils (EVOO) adulteration (blends with cheaper vegetable oils) has been studied by relatively few authors. Analytical methods used for this purpose often involve tedious and solvent-intensive sample preparation prior [...] Read more.
The potential of endogenous n-alkane profiling for the assessment of extra virgin olive oils (EVOO) adulteration (blends with cheaper vegetable oils) has been studied by relatively few authors. Analytical methods used for this purpose often involve tedious and solvent-intensive sample preparation prior to analytical determination, making them unattractive. A rapid and solvent-sparing offline solid phase extraction (SPE) gas chromatography (GC) flame ionization detection (FID) method for the determination of endogenous n-alkanes in vegetable oils was, therefore, optimized and validated. The optimized method demonstrated good performance characteristics in terms of linearity (R2 > 0.999), recovery (on average 94%), and repeatability (residual standard deviation, RSD < 11.9%). The results were comparable to those obtained with online high-performance liquid chromatography (HPLC)-GC- FID ( RSD < 5.1%). As an example of an application to prove the potentiality of endogenous n-alkanes in revealing frauds, the data set obtained from 16 EVOO, 9 avocado oils (AVO), and 13 sunflower oils (SFO), purchased from the market, was subjected to statistical analysis and principal component analysis. Two powerful indices, namely (n-C29 + n-C31)/(n-C25 + n-C26) and n-C29/n-C25, were found to reveal the addition of 2% SFO in EVOO and 5% AVO in EVOO, respectively. Further studies are needed to confirm the validity of these promising indices. Full article
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21 pages, 11308 KB  
Article
Biological Activities of the Fruit Essential Oil, Fruit, and Root Extracts of Ferula drudeana Korovin, the Putative Anatolian Ecotype of the Silphion Plant
by Fatma Tosun, Fatih Göger, Gökalp İşcan, Mine Kürkçüoğlu, Fadıl Kaan Kuran and Mahmut Miski
Plants 2023, 12(4), 830; https://doi.org/10.3390/plants12040830 - 13 Feb 2023
Cited by 7 | Viewed by 5905
Abstract
In the present study, preliminary phytochemical investigations were performed on the fruit essential oil and antioxidant-rich methanolic extracts of the fruits and roots of Ferula drudeana, the putative Anatolian ecotype of the Silphion plant, to corroborate its medicinal plant potential and identify [...] Read more.
In the present study, preliminary phytochemical investigations were performed on the fruit essential oil and antioxidant-rich methanolic extracts of the fruits and roots of Ferula drudeana, the putative Anatolian ecotype of the Silphion plant, to corroborate its medicinal plant potential and identify its unique characteristics amongst other Ferula species. The essential oil from the fruits of the endemic species Ferula drudeana collected from Aksaray was analyzed by GC and GC/MS. The main components of the oil were determined as shyobunone (44.2%) and 6-epishyobunone (12.6%). The essential oil of the fruits and various solvent extracts of the fruits and roots of F. drudeana were evaluated for their antibacterial and anticandidal activity using microbroth dilution methods. The essential oil of the fruits, methanol, and methylene chloride extracts of the fruits and roots showed weak to moderate inhibitory activity against all tested microorganisms with MIC values of 78–2000 µg/mL. However, the petroleum ether extract of the roots showed remarkable inhibitory activity against Candida krusei and Candida utilis with MIC values of 19.5 and 9.75 µg/mL, respectively. Furthermore, all the samples were tested for their antioxidant activities using DPPH TLC spot testing, online HPLC–ABTS screening, and DPPH/ABTS radical scavenging activity assessment assays. Methanolic extracts of the fruits and roots showed strong antioxidant activity in both systems. Full article
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17 pages, 1442 KB  
Article
The Mineral Oil Hydrocarbon Paradox in Olive Pomace Oils
by Raquel B. Gómez-Coca, María del Carmen Pérez-Camino and Wenceslao Moreda
Foods 2023, 12(3), 434; https://doi.org/10.3390/foods12030434 - 17 Jan 2023
Cited by 7 | Viewed by 5354
Abstract
The aim of this work was to understand the actual content of mineral oil hydrocarbons (MOH) in olive pomace oil in order to contribute to the monitoring requested by EFSA for the food groups making a relevant impact on human background exposure. Such [...] Read more.
The aim of this work was to understand the actual content of mineral oil hydrocarbons (MOH) in olive pomace oil in order to contribute to the monitoring requested by EFSA for the food groups making a relevant impact on human background exposure. Such information will complement both the information inferred from the limits established by the EU and the interpretation of the coming toxicological risk assessment. At the same time, the origin of such a group of compounds is discussed. From the raw material to the commercial product, olive pomace oils were sampled and analyzed at different points and/or conditions. Through the ultimate online HPLC-GC-FID system, we gathered information on the MOH concentrations and molecular mass profiles (C-fractions), and through GCxGC-TOF/MS, we identified the key structures that prove the innocuousness of the mineral oil aromatic hydrocarbon (MOAH) fraction. Our approaches provided chromatographic signals on the C10-C50 range, rendering 33–205 mg/kg mineral oil saturated hydrocarbon (MOSH) and 2–55 mg/kg MOAH in the commercial product. The results confirmed that the C25-C35 cut is the main fraction to which humans are exposed via olive pomace oil, showing concentrations highly dependent on the extraction process. Moreover, the identification of the main MOAH groups showed that in olive pomace oil, mainly 1- and 2-ring species were present, being virtually free of the carcinogenic 3–7 ring aromatics. Full article
(This article belongs to the Section Food Quality and Safety)
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18 pages, 3213 KB  
Article
Pattern Recognition Approach for the Screening of Potential Adulteration of Traditional and Bourbon Barrel-Aged Maple Syrups by Spectral Fingerprinting and Classical Methods
by Kuanrong Zhu, Didem P. Aykas and Luis E. Rodriguez-Saona
Foods 2022, 11(15), 2211; https://doi.org/10.3390/foods11152211 - 25 Jul 2022
Cited by 6 | Viewed by 2836
Abstract
This study aims to generate predictive models based on mid-infrared and Raman spectral fingerprints to characterize unique compositional traits of traditional and bourbon barrel (BBL)-aged maple syrups, allowing for fast product authentication and detection of potential ingredient tampering. Traditional (n = 23) [...] Read more.
This study aims to generate predictive models based on mid-infrared and Raman spectral fingerprints to characterize unique compositional traits of traditional and bourbon barrel (BBL)-aged maple syrups, allowing for fast product authentication and detection of potential ingredient tampering. Traditional (n = 23) and BBL-aged (n = 17) maple syrup samples were provided by a local maple syrup farm, purchased from local grocery stores in Columbus, Ohio, and an online vendor. A portable FT-IR spectrometer with a triple-reflection diamond ATR and a compact benchtop Raman system (1064 nm laser) were used for spectra collection. Samples were characterized by chromatography (HPLC and GC-MS), refractometry, and Folin–Ciocalteu methods. We found the incidence of adulteration in 15% (6 out of 40) of samples that exhibited unusual sugar and/or volatile profiles. The unique spectral patterns combined with soft independent modeling of class analogy (SIMCA) identified all adulterated samples, providing a non-destructive and fast authentication of BBL and regular maple syrups and discriminated potential maple syrup adulterants. Both systems, combined with partial least squares regression (PLSR), showed good predictions for the total °Brix and sucrose contents of all samples. Full article
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12 pages, 2953 KB  
Article
Migration of Polypropylene Oligomers into Ready-to-Eat Vegetable Soups
by Chiara Conchione, Paolo Lucci and Sabrina Moret
Foods 2020, 9(10), 1365; https://doi.org/10.3390/foods9101365 - 25 Sep 2020
Cited by 11 | Viewed by 6265
Abstract
Polyolefin oligomeric hydrocarbons (POH) are non-intentionally added substances (NIAS) which mainly reside in the polymer (PE, PP) as a consequence of the polymerization process, and that under favorable conditions (high fat content, high temperature, and long contact time) may migrate at high amount [...] Read more.
Polyolefin oligomeric hydrocarbons (POH) are non-intentionally added substances (NIAS) which mainly reside in the polymer (PE, PP) as a consequence of the polymerization process, and that under favorable conditions (high fat content, high temperature, and long contact time) may migrate at high amount from the packaging into the food. The food industry offers a wide range of ready-to-eat products, among these, vegetable soups designed to be stored at refrigeration temperature (for times around 6 weeks), and in most cases to be heated for a few minutes in a microwave oven (into the original container, mostly of PP) before consumption. The present work aimed to study for the first-time migration of POH during the shelf life of these products, including storage at refrigeration temperature and after microwave heating. On-line high-performance liquid chromatography (HPLC)-gas chromatography (GC), followed by flame ionization detection (FID), was applied for POH analysis in a number of ready-to-eat products purchased from the Italian market. Microwave heating determined a variable POH increase ranging from 0.1 to 6.2 mg/kg. Parameters possibly affecting migration such as fat content and heating time were also studied. Full article
(This article belongs to the Special Issue Emerging Technologies for Determination of Contamination in Foods)
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12 pages, 1411 KB  
Article
Comparison of the Functional Barrier Properties of Chitosan Acetate Films with Conventionally Applied Polymers
by Andrea Walzl, Samir Kopacic, Wolfgang Bauer and Erich Leitner
Molecules 2020, 25(15), 3491; https://doi.org/10.3390/molecules25153491 - 31 Jul 2020
Cited by 5 | Viewed by 3606
Abstract
The current demand to cut back on the use of plastic materials has brought a major boost to the search for bio-based alternatives. Not only are plastic bags and primary food packaging under scrutiny here, but also those materials used as functional barriers [...] Read more.
The current demand to cut back on the use of plastic materials has brought a major boost to the search for bio-based alternatives. Not only are plastic bags and primary food packaging under scrutiny here, but also those materials used as functional barriers to reduce, for example, the migration of mineral oil hydrocarbons (MOH) from recycled paper and board packaging. Most of the barriers now in use are synthetic, often have only moderate barrier functionalities and in addition reduce the environmentally-friendly character of cellulose-based materials. Against this background, bio-based polymers have been evaluated in terms of their functional barrier properties. Chitosan was found to be among the best performers in these materials. In this study, the behavior of a lab-made chitosan acetate film was compared with conventionally produced polymer films. The two-sided migration experiment described recently was used to determine the barrier properties of the tested materials. This not only allowed to test the intrinsic migration of the films and the permeation through them, but also to simulate real packaging situations by using a recycled paper as donor for MOH. The migrated fractions were determined using gas-chromatography-based techniques. While the conventionally produced polymer films showed only moderate barrier function, excellent results were seen for the biopolymer. It reduced the migration from the recycled paper to not detectable, singling it out as a good alternative to conventional materials. Full article
(This article belongs to the Special Issue Food Packaging Materials)
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11 pages, 1805 KB  
Article
Isolation, Genomic and Metabolomic Characterization of Streptomyces tendae VITAKN with Quorum Sensing Inhibitory Activity from Southern India
by Nabila Mohammed Ishaque, Ilia Burgsdorf, Jessie James Limlingan Malit, Subhasish Saha, Roberta Teta, Daniela Ewe, Krishnan Kannabiran, Pavel Hrouzek, Laura Steindler, Valeria Costantino and Kumar Saurav
Microorganisms 2020, 8(1), 121; https://doi.org/10.3390/microorganisms8010121 - 16 Jan 2020
Cited by 17 | Viewed by 6662
Abstract
Streptomyces are among the most promising genera in terms of production ability to biosynthesize a variety of bioactive secondary metabolites with pharmaceutical interest. Coinciding with the increase in genomic sequencing of these bacteria, mining of their genomes for biosynthetic gene clusters (BGCs) has [...] Read more.
Streptomyces are among the most promising genera in terms of production ability to biosynthesize a variety of bioactive secondary metabolites with pharmaceutical interest. Coinciding with the increase in genomic sequencing of these bacteria, mining of their genomes for biosynthetic gene clusters (BGCs) has become a routine component of natural product discovery. Herein, we describe the isolation and characterization of a Streptomyces tendae VITAKN with quorum sensing inhibitory (QSI) activity that was isolated from southern coastal part of India. The nearly complete genome consists of 8,621,231bp with a GC content of 72.2%. Sequence similarity networks of the BGCs detected from this strain against the Minimum Information about a Biosynthetic Gene Cluster (MIBiG) database and 3365 BGCs predicted by antiSMASH analysis of publicly available complete Streptomyces genomes were generated through the BiG-SCAPE-CORASON platform to evaluate its biosynthetic novelty. Crude extract analysis using high-performance liquid chromatography connected to high resolution tandem mass spectrometry (HPLC-HRMS/MS) and dereplication through the Global Natural Product Social Molecular Networking (GNPS) online workflow resulted in the identification of cyclic dipeptides (2, 5-diketopiperazines, DKPs) in the extract, which are known to possess QSI activity. Our results highlight the potential of genome mining coupled with LC-HRMS/MS and in silico tools (GNPS) as a valid approach for the discovery of novel QSI lead compounds. This study also provides the biosynthetic diversity of BGCs and an assessment of the predicted chemical space yet to be discovered. Full article
(This article belongs to the Special Issue Feature Papers in Environmental Microbiology)
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