https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

There has been increasing interest in the research on flavonoids from plant sources because of their versatile health benefits reported in various epidemiological studies. Since flavonoids are directly associated with human dietary ingredients and health, there is need to evaluate structure and function relationship. The bioavailability, metabolism, and biological activity of flavonoids depend upon the configuration, total number of hydroxyl groups, and substitution of functional groups about their nuclear structure. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. Most recent researches have focused on the health aspects of flavonoids for humans. Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators. For pharmaceutical purposes cost-effective bulk production of different types of flavonoids has been made possible with the help of microbial biotechnology. This review highlights the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production.

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Chemistry and Biological Activities of Flavonoids: An Overview

Phenolics and polyphenolics in foods, beverages and spices: Antioxidant activity and health effects – A review

1.1. History
Formaldehyde was described in the year 1855 by the Russian scientist Alexander Michailowitsch Butlerow. The technical synthesis by dehydration of methanol was achieved in 1867 by the German chemist August Wilhelm von Hofmann. The versatility that makes it suitable for use in various industrial applications was soon discovered, and the compound was one of the first to be indexed by Chemical Abstracts Service (CAS). In 1944, Walker published the first edition of his classic work Formaldehyde.(1) Between 1900 and 1930, formaldehyde-based resins became important adhesives for wood and wood composites. The first commercial particle board was produced during World War II in Bremen, Germany. Since 1950, particle board has become an attractive alternative to solid wood for the manufacturing of furniture. Particle board and other wood-based panels were subsequently also used for the construction of housing. Adverse health effects from exposure to formaldehyde in prefabricated houses, especially irritation of the eyes and upper airways, were first reported in the mid-1960s. Formaldehyde emissions from particle boards bonded with urea formaldehyde resin were soon identified as the cause of the complaints. As a consequence, a guideline value of 0.1 ppm was proposed in 1977 by the former German Federal Agency of Health to limit human exposure in dwellings. Criteria for the limitation and regulation of formaldehyde emissions from wood-based materials were established in 1981 in Germany and Denmark. The first regulations followed in the United States in 1985 or thereabouts. In Germany and the United States, large-scale test chambers were used for the evaluation of emissions. Although the chamber method is very reliable, it is also time-consuming and expensive. This meant there was a strong demand for simple laboratory test methods.(2)

Formaldehyde in the Indoor Environment

Evolution of dispersive liquid-liquid microextraction method.

Grapefruit is a rich source of flavonoids but also contains furanocoumarins, which are known to strongly interact with a variety of medications. Thus, characterization of grapefruit furanocoumarin metabolites may help in a better understanding of grapefruit–drug interactions. In the present work, identification of the main metabolites of grapefruit juice furanocoumarins in urine was performed by ultraperformance liquid chromatography (UPLC) coupled to linear ion trap-Orbitrap mass spectrometry (LTQ-Orbitrap). Glucuronides of 6′,7′-dihydroxybergamottin and a hydroxybergamottin-like metabolite were identified for the first time as grapefruit juice metabolites. Afterward, a fast and sensitive method based on solid-phase extraction (SPE) and UPLC coupled to triple quadrupole-tandem mass spectrometry (QqQ-MS/MS) was developed for determination of the identified metabolites in urine. The proposed method was applied to urine samples of five volunteers after intakes of moderate doses of grapefruit, lemon, and ora...

Identification and quantification of grapefruit juice furanocoumarin metabolites in urine: an approach based on ultraperformance liquid chromatography coupled to linear ion trap-Orbitrap mass spectrometry and solid-phase extraction coupled to ultraperformance liquid chromatography coupled to triple quadrupole-tandem mass spectrometry.

Many contaminants are adsorbed by particulate matter suspended in indoor air, which later settles out as house dust, acting as a sink for semi- and non-volatile hazardous substances. Hence, inhalation of indoor air and particulate matter as well as dermal adsorption and unnoticed ingestion of indoor dust, have been recognized as important exposure pathways for organic contaminants. This chapter discusses recent methodological developments for the analysis of emerging pollutants in indoor suspended particulate matter and dust. Procedures for sample collection and enrichment, as well as analyte desorption and clean-up procedures, determination techniques, and method performance evaluation, are discussed. Finally, analytical methodologies available for several families of contaminants usually associated to indoor particulate matter and dust are presented.

Analytical Developments for Emerging Pollutants in Indoor Suspended Particulate Matter and Dust

This chapter reviews and discuses recent literature related to methodological developments for the analysis of pollutants in indoor air, focusing the attention on emergent contaminants and biocides, which their environmental and health concern are increasing and are extensively found in indoor air. Some of them are suspected to behave as priority organic pollutants and/or endocrine disrupting compounds, and can be found both in the air gas phase and also associated to the suspended particulate matter and settled dust. The high comfort achieved in developed countries, increased the demand and the widespread consumption of biocides and fragranced household products. In addition, people in developed countries spend up to 90% of their time indoors. Inadequate ventilation coupled with the slow indoor degradation processes may increase indoor pollution levels. High temperature and humidity levels can also increase concentrations of some pollutants. Hence, inhalation of indoor air is potentially the most important exposure pathway to many pollutants. The chemicals that are extensively found in indoor environments include compounds that are suspected to behave as priority organic pollutants and endocrine disrupting compounds such as phthalate esters, polybrominated and phosphate flame retardants, fragrances, pesticides, biocides, and other organic compounds such as organotin and perfluorinated alkyl compounds that are of increasing concern as indoor pollutants. This chapter reports analytical developments and applications regarding the considered contaminants in the indoor environment, paying main attention to the sampling and analysis of the gas phase indoors. Available sorbents for sample collection, as well as analyte desorption techniques, clean-up procedures, determination techniques, and method performance evaluation will be summarized and discussed. © 2009 Nova Science Publishers, Inc. All rights reserved.

Jorge Regueiro

Papers

Analytical Developments for Emerging Pollutants in Indoor Suspended Particulate Matter and Dust

The use of sorbents for the analysis of emerging pollutants in indoor air