Lamiaceae species are promising potential sources of natural antioxidants, owing to their high polyphenol content. In addition, increasing scientific and epidemiological evidence have associated consumption of foods rich in polyphenols with health benefits such as decreased risk of cardiovascular diseases mediated through anti-inflammatory effects. The complex and diverse nature of polyphenols and the huge variation in their levels in commonly consumed herbs make their analysis challenging. Innovative robust analytical tools are constantly developing to meet these challenges. In this review, we present advances in the state of the art for the identification and quantification of polyphenols in Lamiaceae species. Novel chromatographic techniques that have been employed in the past decades are discussed, ranging from ultra-high-pressure liquid chromatography to hyphenated spectroscopic methods, whereas performance characteristics such as selectivity and specificity are also summarized.

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Background and objectives:Aging is characterized by a functional shift of the immune system towards a proinflammatory phenotype. This derangement has been associated with cognitive decline and has been implicated in the pathogenesis of dementia. Diet can modulate systemic inflammation; thus, it may be a valuable tool to counteract the associated risks for cognitive impairment and dementia. The present study aimed to explore the associations between the inflammatory potential of diet, assessed using an easily applicable, population-based, biomarker-validated diet inflammatory index (DII), and the risk for dementia in community-dwelling older adults.Methods:Individuals from the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD) were included in the present cohort study. Participants were recruited through random population sampling, and were followed for a mean of 3.05 (SD=0.85) years. Dementia diagnosis was based on standard clinical criteria. Those with baseline dementia and/or missing cognitive follow-up data were excluded from the analyses. The inflammatory potential of diet was assessed through a DII score which considers literature-derived associations of 45 food parameters with levels of pro- and anti-inflammatory cytokines in the blood; higher values indicated a more pro-inflammatory diet. Consumption frequencies were derived from a detailed food frequency questionnaire, and were standardized to representative dietary intake normative data from 11 different countries. Analysis of dementia incidence as a function of baseline DII scores was performed by Cox proportional hazards models.Results:Analyses included 1059 individuals (mean age=73.1 years; 40.3% males; mean education=8.2 years), 62 of whom developed incident dementia. Each additional unit of DII was associated with a 21% increase in the risk for dementia incidence [HR=1.21 (1.03 – 1.42); p=0.023]. Compared to participants in the lowest DII tertile, participants in the highest one (maximal pro-inflammatory diet potential) were 3 [(1.2 – 7.3); p=0.014] times more likely to develop incident dementia. The test for trend was also significant, indicating a potential dose-response relationship (p=0.014).Conclusions:In the present study, higher DII scores (indicating greater pro-inflammatory diet potential) were associated with an increased risk for incident dementia. These findings might avail the development of primary dementia preventive strategies through tailored and precise dietary interventions.

The impact of dechlorophyllization (n‐hexane: water partitioning, activated charcoal bleaching, and ChloroFiltr® decolorization) on major polyphenols of two herbal by‐products (rosemary and thyme) was assessed. The aim was to produce decolorized extracts for food preservation and improve the quantification of their main phenolics. Activated charcoal bleaching and ChloroFiltr® decolorization effectively removed the chlorophyll a and b, whereas traces were detected after n‐hexane: water partitioning. Dechlorophyllized thyme extracts prepared using activated charcoal and ChloroFiltr® had the lowest relative antioxidant capacity index (RACI) values based on 2,2‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS), ferric reducing antioxidant power (FRAP), and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) antioxidant assays. Conversely, rosemary extracts had positive RACI values following treatment with activated charcoal, whereas n‐hexane led to a significant antioxidant loss. Chromatography‐mass spectrometry analyses indicated that phenolic diterpenes (carnosol and carnosic acid), as well as rosmarinic acid were in general not significantly decreased (p ˃ .05) after activated charcoal treatment, while n‐hexane maintained the flavonoids and phenolic acids with nonsignificant losses. Practical applications Commercial exploitation of polyphenol‐rich plant based extracts as natural antioxidant agents is impeded by their high chlorophyll content, which when incorporated in food products can result in products that do not meet the consumer expectations for appearance. This study has shown that the activated charcoal bleaching has potentials to remove chlorophyll and retain antioxidant polyphenols in particular diterpenes in fresh herb by‐products. Moreover, the commonly used n‐hexane was less effective in removing chlorophyll but retained the major flavonoids and phenolic acids. Thus, the choice of chlorophyll removal methods depend on retaining the class of antioxidant polyphenols abundant in the plant matrix.

This study was undertaken with the aim of establishing a correlation between the extraction yield in total flavonoids from red grape pomace and the extraction temperature, using 0.5% (w/v) aqueous lactic acid as the solvent system. Extraction of flavonoids was found to obey second-order kinetics, and on such a basis, the yield in total flavonoids at saturation could be very effectively determined and correlated with temperature using non-linear regression. The results indicated that the extraction yield at saturation is highly correlated with temperature, following a quadratic function. The extract obtained at 40 °C had an optimal predicted total flavonoid yield of 13.27 mg rutin equivalents per gram of dry weight, and it was further analyzed by liquid chromatography-mass spectrometry to characterize its major constituents. The polyphenols detected were flavanols, flavonols and an anthocyanin. The outcome of this study outlined that temperatures above 40 °C are rather unfavorable for flavonoid extraction from red grape pomace, as suggested by the model established through kinetics.

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Berries have been widely assessed for their beneficial health effects, predominately due to their high (poly)phenol content of anthocyanins and ellagitannins. After ellagitannins and ellagic acid are metabolized by the gut microbiome, a class of compounds known as urolithins are produced, which exert potential advantageous health effects. Anthocyanins, on the other hand, undergo a complex metabolic pathway after their interaction with microbial and endogenous enzymes, forming a broad range of metabolites and catabolic products. In most cases, in vitro models and cell lines are used to generate metabolites, whereas their assessment in vivo is currently limited. Thus far, several analytical methods have been developed for the qualitative and quantitative analysis of phenolic metabolites in berries, including liquid chromatography, mass spectrometry, and other hyphenated techniques, and have been undoubtedly valuable tools for the detailed metabolite characterization and profiling. In this review, a compilation of studies providing information on the qualitative and quantitative analysis of (poly)phenol metabolites in blackberries and raspberries after the utilization of in vitro and in vivo methods is presented. The different analytical techniques employed are assessed, focusing on the fate of the produced metabolic compounds in order to provide evidence on their characteristics, formation, and beneficial effects.

Potato is one of the most important and common tubers for human consumption globally, constituting an excellent source of energy and nutrients. In modern times, there is an increasing demand of minimally processed, that is, ready‐to‐cook, potatoes as a result of a busy lifestyle and/or preference for convenience of consumers. However, minimally processed potatoes are prone to enzymatic browning which is the main challenge of industrial potato processing. The use of chemicals such as sulfites as anti‐browning agents is being questioned for health‐safety since they are categorized as severe allergens. The potato processing industry is thus looking for alternative methods of preservation to prevent browning. This review summarizes critical information on anti‐browning methods of minimally processed potato products providing key‐findings of studies using various heating treatments, anti‐browning chemical agents, packaging formulations, and emerging non‐thermal technologies. Novelty impact statement Consumption of minimally processed potatoes has increased owing to their convenience for commercialization. However, the partial processing causes an increase in the perishability of potatoes. This review covers recent progress and advances in anti‐browning methods of minimally processed potatoes that can be used as alternatives or complementary to the conventional methods.