Determination of adulteration, geographical origins, and species of food by mass spectrometry

Food adulteration, mislabeling, and fraud, are rising global issues. Therefore, a number of precise and reliable analytical instruments and approaches have been proposed to ensure the authenticity and accurate labeling of food and food products by confirming that the constituents of foodstuffs are of the kind and quality claimed by the seller and manufacturer. Traditional techniques (e.g., genomics-based methods) are still in use; however, emerging approaches like mass spectrometry (MS)-based technologies are being actively developed to supplement or supersede current methods for authentication of a variety of food commodities and products. This review provides a critical assessment of recent advances in food authentication, including MS-based metabolomics, proteomics and other approaches.

Determination of the geographic origin of 52 honey samples based on the assessment of anionic content profiling with a new algorithm using monolithic column-based micellar nano-liquid chromatography

In the present study, a new micellar nano LC-UV was, for the first time, reported for the separation and determination of five anions (chloride, nitrite, bromide, sulfate and nitrate) in 52 honey samples. Based on this approach, a graphene oxide-based monolithic column was prepared and applied for the samples. Various amounts of hexadecyltrimethyl-ammonium bromide (HTAB) in the mobile phase were used in order to optimize the separation conditions. The baseline separation was achieved using mobile phase with 25/75% (v/v) ACN/10 mM phosphate buffer at pH 3.4, while the amount of HTAB was optimized as 0.22 mM in the mobile phase. The whole method was validated and it leads to high sensitivity. The LOD values were found in the range of 0.02-0.22 µg/kg, while LOQ values were found in the range of 0.06-0.18 µg/kg. The method allowed to achieve sensitivity analyses of anionic content in 52 honey samples. All data were evaluated using a new algorithm for geographic origin discrimination. K-nearest neighbor algorithm (K-NN), cubic support vector classifier (K-DVS), and K-Mean cluster analysis were used for geographic origin discrimination of honeys. The accuracy of the whole model was calculated as 94.4% with the K-DVS method. The samples from five provinces were classified 100% correctly, while two of them were classified with one misclassification, with an accuracy of 89.9% and 83.3%, respectively. PRACTICAL APPLICATION: The new platforms and advanced technologies are crucial for advanced food analysis. In this article, a novel methodology was attempted for the determination of geographic origin of 52 honey samples. In this sense, micellar nano LC technique with a homemade monolithic nano-column was, for the first time, applied for the anion analysis using a new algorithm.

A Comprehensive Survey of Phenolic Constituents Reported in Monofloral Honeys around the Globe

The aim of this review is to provide a comprehensive overview of the large variety of phenolic compounds that have to date been identified in a wide range of monofloral honeys found globally. The collated information is structured along several themes, including the botanical family and genus of the monofloral honeys for which phenolic constituents have been reported, the chemical classes the phenolic compounds can be attributed to, and the analytical method employed in compound determination as well as countries with a particular research focus on phenolic honey constituents. This review covers 130 research papers that detail the phenolic constituents of a total of 556 monofloral honeys. Based on the findings of this review, it can be concluded that most of these honeys belong to the Myrtaceae and Fabaceae families and that Robinia (Robinia pseudoacacia, Fabaceae), Manuka (Leptospermum scoparium, Myrtaceae), and Chestnut (Castanea sp., Fagaceae) honeys are to date the most studied honeys for phenolic compound determination. China, Italy, and Turkey are the major honey phenolic research hubs. To date, 161 individual phenolic compounds belonging to five major compound groups have been reported, with caffeic acid, gallic acid, ferulic acid and quercetin being the most widely reported among them. HPLC with photodiode array detection appears to be the most popular method for chemical structure identification.

Monofloral Honeys as a Potential Source of Natural Antioxidants, Minerals and Medicine

Background: vegetative diversity is based on different climate and geographical origins. In terms of beekeeping, herbal diversity is strongly correlated to the production of a wide variety of honey. Therefore, based on the existing plant diversity in each country, multiple honey varieties are produced with different health characteristics. While beekeeping potential and consumption preferences are reflected in products’ variety, this leads to an increase in the region’s economy and extensive export. In the last years, monofloral honey has gained interest from consumers and especially in the medicinal field due to the presence of phytochemicals which are directly linked to health benefits, wound healing, antioxidant, anticancer and anti-inflammatory activities. Scope and approach: this review aims to highlight the physicochemical properties, mineral profiles and antioxidant activities of selected monofloral honeys based on their botanical and geographical origin. Moreover, this review focuses on the intercorrelation between monofloral honey’s antioxidant compounds and in vitro and in vivo activities, focusing on the apoptosis and cell proliferation inhibition in various cell lines, with a final usage of honey as a potential therapeutic product in the fight towards reducing tumor growth. Key findings and conclusions: multiple studies have demonstrated that monofloral honeys have different physicochemical structures and bioactive compounds. Useful chemical markers to distinguish between monofloral honeys were evidenced, such as: 2-methoxybenzoic acid and trimethoxybenzoic acid are distinctive to Manuka honey while 4-methoxyphenylacetic acid is characteristic to Kanuka honey. Furthermore, resveratrol, epigallocatechin and pinostrobin are markers distinct to Sage honey, whereas carvacrol and thymol are found in Ziziphus honey. Due to their polyphenolic profile, monofloral honeys have significant antioxidant activity, as well as antidiabetic, antimicrobial and anticancer activities. It was demonstrated that Pine honey decreased the MDA and TBARS levels in liver, kidney, heart and brain tissues, whereas Malicia honey reduced the low-density lipoprotein level. Consumption of Clover, Acacia and Gelam honeys reduced the weight and adiposity, as well as trygliceride levels. Furthermore, the antiproliferative effect of chrysin, a natural flavone in Acacia honey, was demonstrated in human (A375) and murine (B16-F1) melanoma cell lines, whereas caffeic acid, a phenolic compound found in Kelulut honey, proves to be significant candidate in the chemoprevention of colon cancer. Based on these features, the use of hiney in the medicinal field (apitherapy), and the widespread usage of natural product consumption, is gaining interest by each year.

Acacia honey from different altitudes: total phenols and flavonoids, laser-induced fluorescence (LIF) spectra, and anticancer activity

Objective

To investigate Acacia honey from different altitudes regarding total phenols and flavonoids, laser-induced fluorescence (LIF) spectra and anticancer activity against human cancer cell lines.

Methods

Anticancer activity was investigated using sulforhodamine B cytotoxicity assays in the following human cancer cell lines: HCT116 (colon); MCF7 (breast), and HepG2 (liver). Total phenols and flavonoids were measured using spectrophotometric methods and LIF was used to differentiate between low and high-altitude honey.

Results

The LIF spectra differed between low and high-altitude Acacia honey. High altitude Acacia honey was characterized by significantly lower total phenol content (81.47 ± 1.25 mg gallic acid equivalent [GAE]/100 g) and increased total flavonoids (10.63 ± 0.53 mg quercetin equivalent [QE]/100 g) versus low altitude Acacia honey (91.33 ± 0.96 mg GAE/100 g and 8.78 ± 0.23 mg QE/100 g, respectively). Low altitude Acacia honey displayed increased IC₅₀ values against HCT116 and MCF7 cells (264.17 ± 10.5 and 482.65 ± 20.3 µg/ml, respectively) versus high altitude Acacia honey (117.99 ± 12.7 and 189.82 ± 15.8 µg/ml, respectively).

Conclusions

High altitude Acacia honey had significantly more effective anticancer activity against HCT116 and MCF7 cells compared with low altitude honey.

Choices of chromatographic methods as stability indicating assays for pharmaceutical products: A review

Stability indicating assay describes a technique which is used to analyse the stability of drug substance or active pharmaceutical ingredient (API) in bulk drug and pharmaceutical products. Stability indicating assay must be properly validated as per ICH guidelines. The important components in a stability indicating assay include sensitivity, specificity, accuracy, reliability, reproducibility and robustness. A validated assay is able to measure the concentration changes of drug substance/API with time and make reliable estimation of the quantity of the degradation impurities. The drug substance is separated and resolved from the impurities. Pros and cons of HPLC, GC, HPTLC, CE and SFC were discussed and reviewed. Stability indicating assay may consist of the combination of chromatographic separation and spectroscopic detection techniques. Hyphenated system could demonstrate parallel quantitative and qualitative analysis of drug substances and impurities. Examples are HPLC-DAD, HPLC-FL, GC-MS, LC-MS and LC-NMR. The analytes in the samples are separated in the chromatography while the impurities are chemically characterised by the spectroscopy in the system. In this review, various chromatographic methods which had been employed as stability indicating assays for drug substance and pharmaceutical formulation were systematically reviewed, and the application of hyphenated techniques in impurities characterisation and identification were also discussed with supporting literatures.

HPTLC-densitometry quantification of fructooligosaccharides from inulin hydrolysate

The objective of present research was to develop an easy, precise and accurate HPTLC densitometry method for quantification of fructooligosaccharides (FOSs) from inulin hydrolysate. The chromatographic separation of FOSs was performed on pre-coated silica gel (60, F₂₅₄) TLC plates using a mobile phase (butanol:ethanol:water, 60:24:16), and densitometry evaluation of FOSs was performed at A₅₀₀. Both kestose and nystose were successfully resolved with R_f value of 0.43 and 0.34, respectively. The accuracy, reliability and reproducibility of developed method was assessed by percent relative standard deviation of kestose and nystose for instrument precision (1.43% and 1.50%), repeatability (1.48% and 1.56%), intra-day precision (1.60% and 1.63%), inter-day precision (1.62% and 1.66%), limit of detection (4.58 ng/spot and 4.58 ng/spot), limit of quantification (13.87 ng/spot and 13.89 ng/spot) and recovery (98.81% and 98.69%). Moreover, overlapping spectra of test sample with standard confirms the specificity of developed method, which was validated as per ICH guidelines.

Naringin derivatives as glucosamine-6-phosphate synthase inhibitors based preservatives and their biological evaluation

Glucosamine-6-Phosphate synthase enzyme has been targeted for development of better and safe preservative due to its role in microbial cell wall synthesis. In recent year’s demand of preservatives for the food, cosmetics and pharmaceuticals have increased. Although, the available synthetic preservatives have associated unwanted adverse effects, soa chain of naringin derivatives were schemed synthesized and judged for antioxidant, antimicrobial, preservative efficacy, stability study and topical evaluation. Molecular docking resulted with excellent dock score and binding energy for compound 7, compound 6 and compound 1 as compared to standard drugs. Resultant data of antimicrobial activity revealed compound 7as most potent antimicrobial compound for P. mirabilis, P. aeruginosa, S. aureus, E. coli, C. albicans, and A. niger, respectively, as compared to the standard drugs. The preservative efficacy test of compound 7 in White Lotion USP showed the log cfu/mL value within prescribed limit of USP standard. Compound 7 stabilize the White lotion USP from microbial growth for a period of six months under accelerated storage condition. Compound 7 was further evaluated for toxicity by using the Draize test in rabbits and showed no sign of eye and skin irritation. The outcome demonstrated that synthesized naringin compounds showed glorious antioxidant, antimicrobial, preservative efficacy, stable and safe as compared to standards.

Adverse effects of honey on low-density lipoprotein cholesterol and adiponectin concentrations in patients with type 2 diabetes: a randomized controlled cross-over trial

Background

Due to phenolic and fructose content, honey may be a suitable sweetener for patients with type 2 diabetes. However, its effect on oxidative and inflammatory status of diabetes patients is not clear. We aimed to investigate the effect of natural honey on some of oxidative, inflammatory, and anti-inflammatory markers of patients with type 2 diabetes.

Methods

In a randomized controlled cross-over trial, 43 patients with type 2 diabetes were allocated to isocaloric conditions with either dietary recommendations (control) or natural honey (50 g/day) plus dietary recommendations (honey) for 8 weeks with one month washout period in between. Serum lipids, malondialdehyde (MDA), total antioxidant capacity (TAC), high-sensitivity C-reactive protein (hs-CRP), and adiponectin levels were measured at baseline and the end of each sequence.

Results

Malondialdehyde (10.9%, P = 0.01), hs-C reactive protein (10.6%, P = 0.003), and adiponectin (7.1%, P < 0.001) concentrations significantly decreased in honey condition. Low-density lipoprotein cholesterol (LDL-C) (16.8%, P < 0.001) significantly decreased in control and high-density lipoprotein cholesterol (HDL-C) significantly increased in both conditions. Between-group differences were only statistically significant for adiponectin (P = 0.005) and LDL-C (P = 0.005).

Conclusions

Consumption of 50 g/day honey had adverse effects on LDL-C and adiponectin levels in patients with type 2 diabetes. Honey may need to be consumed with caution in type 2 diabetes patients.

Extraction approaches used for the determination of biologically active compounds (cyclitols, polyphenols and saponins) isolated from plant material

Based on the bioactive properties of certain compounds, such as antioxidant and anti-inflammatory activities, an interesting subject of research are natural substances present in various parts of plants. The choice of the most appropriate method for separation and quantification of biologically active compounds from plants and natural products is a crucial step of any analytical procedure. The aim of this review article is to present an overview of a comprehensive literature study from the last 10 years (2007-2017), where relevant articles exposed the latest trends and the most appropriate methods applicable for separation and quantification of biologically active compounds from plant material and natural products. Consequently, various extraction methods have been discussed, together with the available procedures for purification and pre-concentration and dedicated methods used for analysis.

Isolation, Separation, and Preconcentration of Biologically Active Compounds from Plant Matrices by Extraction Techniques

Development of efficient methods for isolation and separation of biologically active compounds remains an important challenge for researchers. Designing systems such as organomineral composite materials that allow extraction of a wide range of biologically active compounds, acting as broad-utility solid-phase extraction agents, remains an important and necessary task. Selective sorbents can be easily used for highly selective and reliable extraction of specific components present in complex matrices. Herein, state-of-the-art approaches for selective isolation, preconcentration, and separation of biologically active compounds from a range of matrices are discussed. Primary focus is given to novel extraction methods for some biologically active compounds including cyclic polyols, flavonoids, and oligosaccharides from plants. In addition, application of silica-, carbon-, and polymer-based solid-phase extraction adsorbents and membrane extraction for selective separation of these compounds is discussed. Potential separation process interactions are recommended; their understanding is of utmost importance for the creation of optimal conditions to extract biologically active compounds including those with estrogenic properties.

Honey flavonoids inhibit hOATP2B1 and hOATP1A2 transporters and hOATP-mediated rosuvastatin cell uptake in vitro

1. Some flavonoids contained in the common diet have been shown to interact with important membrane uptake transporters, including organic anion transporting polypeptides (OATPs). OATP2B1 and OATP1A2 expressed in the apical membrane of human enterocytes may significantly contribute to the intestinal absorption of drugs, e.g. statins. This study is aimed at an evaluation of the inhibitory potency of selected food honey flavonoids (namely galangin, myricetin, pinocembrin, pinobanksin, chrysin and fisetin) toward hOATP2B1 and hOATP1A2 as well as at examining their effect on the cellular uptake of the known OATP substrate rosuvastatin. 2. Cell lines overexpressing the hOATP2B1 or hOATP1A2 transporter were employed as in vitro model to determine the inhibitory potency of the flavonoids toward the OATPs. 3. Chrysin, galangin and pinocembrin were found to inhibit both hOATP2B1 and hOATP1A2 in lower or comparable concentrations as the known flavonoid OATP inhibitor quercetin. Galangin, chrysin and pinocembrin effectively inhibited rosuvastatin uptake by hOATP2B1 with IC₅₀ ∼1-10 μM. The inhibition of the hOATP1A2-mediated transport of rosuvastatin by these flavonoids was weaker. 4. The found data indicate that several of the tested natural compounds could potentially affect drug cellular uptake by hOATP2B1 and/or hOATP1A2 at relative low concentrations, a finding which suggests their potential for food-drug interactions.

Recent Advances in the Analysis of Phenolic Compounds in Unifloral Honeys

Honey is one of the most renowned natural foods. Its composition is extremely variable, depending on its botanical and geographical origins, and the abundant presence of functional compounds has contributed to the increased worldwide interest is this foodstuff. In particular, great attention has been paid by the scientific community towards classes of compounds like phenolic compounds, due to their capability to act as markers of unifloral honey origin. In this contribution the most recent progress in the assessment of new analytical procedures aimed at the definition of the qualitative and quantitative profile of phenolic compounds of honey have been highlighted. A special emphasis has been placed on the innovative aspects concerning the extraction procedures, along with the most recent strategies proposed for the analysis of phenolic compounds. Moreover, the centrality of validation procedures has been claimed and extensively discussed in order to ensure the fitness-for-purpose of the proposed analytical methods. In addition, the exploitation of the phenolic profile as a tool for the classification of the botanical and geographical origin has been described, pointing out the usefulness of chemometrics in the interpretation of data sets originating from the analysis of polyphenols. Finally, recent results in concerning the evaluation of the antioxidant properties of unifloral honeys and the development of new analytical approaches aimed at measuring this parameter have been reviewed.