The article is a continuation of the book chapter entitled Recent Advances in Antioxidant Capacity Assays published by IntechOpen in 2021. The various methods for determining antioxidant capacity in a variety of materials (plant extracts, biological material, foods, etc.) are discussed, with a special emphasis on articles published in recent years and especially on reviews. Both chemical methods for determining antioxidant capacity and cellular antioxidant capacity assays were presented. In addition to the review published in 2021, the following methods for the determination of antioxidant capacity were presented: crocin bleaching assay, Briggs-Rauscher reaction inhibition assay, ferricyanide-Prussian blue assay, cerric reducing antioxidant capacity assay and Anti Oxidant Power 1 (AOP1) assay. Several applications of the cellular antioxidant capacity assay were also presented in tabular form.

This work presents a survey of the important antioxidant capacity/activity assays applied for a diversity of samples including plant extracts, foods, biological material, etc. The published materials are critically discussed, emphasizing the recent findings in the field. New and emergent antioxidant capacity assays, such as nanoparticles-based assay, are also presented. The discussion includes chemical-based methods as well as biochemical and cellular assays. Chemical methods detailed are radical/ROS-based scavenging assays (the trolox equivalent antioxidant capacity (TEAC/ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC) assays, chemiluminescence methods, total radical-trapping antioxidant parameter (TRAP), total oxy radical scavenging capacity (TOSC), and β-carotene bleaching assays), non-radical redox potential-based assays (ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), nanoparticle-based methods and electrochemical methods), metal chelation capacity and total phenolic content tests. The biochemical-based assays and in vivo assays discussed include the oxidation of low density lipoprotein (LDL), the thiobarbituric acid reactive substances (TBARS) and the cellular antioxidant activity (CAA) assays. While a direct link between the antioxidant capacity and health benefits is still a matter of debate, the antioxidant testing methodologies presented in this chapter remain valuable for the high efficiency and cost-effective evaluation of antioxidants, from compound discovery to quality control.

Antioxidant activity of some ethanol extracts of Calendula (marigold) flowers and chloroform fraction of extracts were evaluated. By an optimized electron paramagnetic resonance (EPR) spectroscopy method using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical was determined antioxidant activity of chloroform fraction of each extract. The decrease in time of DPPH center dot concentration in the reaction medium was studied and it was noted that the reaction mechanism is characterized by two different reaction rates. Antioxidant activity of ethanol extracts was determined by spectrophotometric DPPH free radical scavenging activity method and the content of polyphenols in extracts was performed by LC-MS and spectrophotometric analysis methods. Results showed that fat soluble compounds are mainly responsible of the antioxidant activity of extracts. Analyzed extracts showed higher antioxidant activity than BHT (butylated hydroxytoluen), synthetic antioxidant compound.

This work proposes a novel method for determining the composition of mixtures of natural polyphenolic compounds: caffeic acid, gallic acid, ellagic acid, rosmarinic acid and quercitrin in plants. The method is based on the formation of colored spots by these compounds upon reaction with nano-oxides of Al2O3, ZnO, MgO, CeO2, TiO2 and MoO3 impregnated on filter paper and constituting a colorimetric sensor array (CSA). The image of the colored spots was analyzed and the intensity of the blue colour (BCI) component has shown maximum sensitivity in relation to phenolic compounds. The inverse of BCI was linearly correlated with the logarithm of the individual phenolic compound concentrations. Chemometric analysis by partial least squares regression (PLSR) of 1/BCI values for 24 synthetic mixtures of the 5 phenolic compounds measured with the colorimetric sensor array has demonstrated good correlation between the actual and the predicted concentration of quercitrin. For the other phenolic compounds, the colors measured with the colorimetric sensor array were greatly influenced by the concentrations of the other components in the mixture. The method was applied to the determination of quercitrin in medicinal teas and the results were compared to those obtained by HPLC. The discussion of the results emphasizes possible interferences in the tea samples. While further optimization of the colorimetric sensor array-based method appears necessary, tailored to the particular targeted application in real samples, the proposed method for polyphenol determination has advantages that include simplicity, low cost, and portability.

The antioxidant properties of different plant extracts are usually claimed and used by food, medicine and cosmetic industry due to their health promoting capacities. In this study the presence of antioxidant compounds and the total antioxidant capacity of water-soluble extracts, prepared using two extraction methods and a variety of solvents, have been determined and a rapid screening method has been developed. Plant extracts characterisation, composition and antioxidant properties were confirmed by FTIR and Raman spectroscopies. Voltammetry, amperometry and electrochemical impedance were used to highlight the total antioxidant capacity of each extract using an electrochemical gold nanozyme-sensor based on the enzyme-like catalytic activity of gold nanoparticles. Both anodic area of cyclic voltammograms (10.31 μA V) and electrochemical index (153) calculated using differential potential voltammetry show the total content of antioxidant compounds, allowing to discriminate between different extracts. Amperometric total antioxidant capacity measurements were associated with those from classical chemiluminescence and good correlation has been found (Pearson's correlation coefficient of 0.958).

The antioxidant activity, total phenolic content, and total flavonoid content of 10 edible mushrooms species, including cultivated (Pleurotus ostreatus, Agaricus bisporus white and brown) and wild (P. ostreatus, Macrolepiota procera, Cantharellus cibarius, Russula vesca, Russula alutacea, Boletus edulis and Agaricus campestris), were determined. The extraction was performed using water and 50% water-ethanol and the caps and stipe were investigated separately. Water was the most appropriate solvent for phenolic compounds regardless of the sample. In contrast, the presence of ethanol in the solvent increased the extraction of flavonoids for cultivated P. ostreatus (caps and stipe), and wild R. alutacea, R. vesca, A. campestris, P. ostreatus (only caps) and C. cibarius, M. procera (only stipe). Significant differences between the antioxidant activities of the samples were registered in relationship with the different solvents. The antioxidant activity of water extract of dried A. bisporus brown (cultivated) showed the strongest 1,1-diphenyl-2-picrylhydrazyl radicals-scavenging assay (88.64%), while the B. edulis hydroalcoholic extract contained 74.93%. A detailed investigation into the functional group of phenolics and other organic compounds responsible with the antioxidant activity has been performed using Fourier transform infrared spectroscopy. The infrared spectra showed that the solvent-type directly influences the extraction process and, hence, the antioxidant activity. The present study contributes to information concerning mushrooms as sources of biologically active compounds. To investigate the correlations between phytochemical characteristics (i.e., phenolics, flavonoids and antioxidant activity) closely related to nature of solvents, the statistical analysis was performed.

This paper presents a new way to assess the environmental impact on historical artifacts using binary logistic regression. The prediction of the impact on the exhibits during certain pollution scenarios (environmental impact) was calculated by a mathematical model based on the binary logistic regression; it allows the identification of those environmental parameters from a multitude of possible parameters with a significant impact on exhibitions and ranks them according to their severity effect. Air quality (NO2, SO2, O3 and PM2.5) and microclimate parameters (temperature, humidity) monitoring data from a case study conducted within exhibition and storage spaces of the Romanian National Aviation Museum Bucharest have been used for developing and validating the binary logistic regression method and the mathematical model. The logistic regression analysis was used on 794 data combinations (715 to develop of the model and 79 to validate it) by a Statistical Package for Social Sciences (SPSS 20.0). The results from the binary logistic regression analysis demonstrated that from six parameters taken into consideration, four of them present a significant effect upon exhibits in the following order: O3>PM2.5>NO2>humidity followed at a significant distance by the effects of SO2 and temperature. The mathematical model, developed in this study, correctly predicted 95.1 % of the cumulated effect of the environmental parameters upon the exhibits. Moreover, this model could also be used in the decisional process regarding the preventive preservation measures that should be implemented within the exhibition space.IMPLICATIONS:The paper presents a new way to assess the environmental impact on historical artifacts using binary logistic regression. The mathematical model developed on the environmental parameters analyzed by the binary logistic regression method could be useful in a decision-making process establishing the best measures for pollution reduction and preventive preservation of exhibits.

Ten edible mushroom species collected from four sites of Dambovita County, Romania, were analyzed through ICP-MS technique in order to evaluate their content in Fe, Cu, Zn, Pb and Cd, both in cap and stipe. Wild growing species (Russula vesca, Russula alutacea, Macrolepiota procera, Cantharellus cibarius, Boletus edulis, Agaricus campestris and Pleurotus ostreatus) and cultivated species (Pleurotus ostreatus, Agaricus bisporus white and Agaricus bisporus brown) were taken into account. The data related to the elemental composition of the fruiting bodies of mushrooms are important to be known having in view the nutritional and food safety related aspects. Higher concentrations of copper, iron and zinc have been found in Pleurotus ostreatus (cap), Macrolepiota procera (stipe) and Pleurotus ostreatus cultivated (cap) respectively, as follows: 43.90 +/- 0.96 mu g/g d.w., 715.15 +/- 4.52 mu g/g d.w. and 379.33 +/- 2.05 mu g/g d.w. Although significant Health Risk Index were determined for lead in Agaricus campestris (about 0.1 both in cap and stipe) and for cadmium in Pleurotus ostreatus (0.58 in cap), these values are under the regulated PTWI limits for adult person.

It is studied a batch analytical method based on the system Co(II)EDTA/luminol/H2O2 for the determination of antioxidant capacity of different types of sample. The method is based on the oxidation and chemiluminescence of luminol under the influence of reactive oxygen species produced in a Fenton type reaction of hydrogen peroxide with Co(II). The antioxidants from a sample react with the reactive oxygen species and decrease the chemiluminescence signal. It was drawn a calibration graph by plotting the ratio of chemiluminescence intensity in the absence and in the presence of an antioxidant and the concentration of a standard antioxidant (gallic acid). The calibration graph is linear in the domain 10(-6) - 10(-4) M galic acid. The method was applied for the analysis of three types of fruit juices. It has been done a comparison between the results for antioxidant capacity determination obtained with the developed method and the literature data for similar types of samples. The acuracy of the method was verified by using standard addition method.

Valahia University of Targoviste, Faculty of Environmental Engineering and Food Science, 130004 Targoviste, Romania E-mail: antonia.georgescu@gmail.com 2 University of Bucharest, Faculty of Chemistry, 050657 Bucharest, Romania Valahia University of Targoviste, Faculty of Sciences and Arts, 130024 Targoviste, Romania Valahia University of Targoviste, Multidisciplinary Research Institute for Sciences and Technologies, 130004 Targoviste, Romania Horia Hulubei Institute of Physics and Nuclear Engineering, 077125 Magurele, Romania University of Bucharest, Doctoral School in Chemistry, 050657, Bucharest, Romania Corresponding author: Cristiana Radulescu E-mail: radulescucristiana@yahoo.com

National Museum of Romanian Aviation is the only museum of its kind in the country who holds in a historical succession the evolution of the Romanian aeronautics starting from Traian Vuia and Aurel Vlaicu until today. Documents, models and aircraft exhibited in the museum, many of them being unique, can be irreversibly degraded under the action of chemical air contaminants and/or inadequate microclimate conditions. The article presents the results of air quality assessment within the main exhibition space of the museum, Hangar 1, obtained in a study organized in 2014-2015. Given the specific of the museum and its location, in a city with intense traffic, both indoor and outdoor concentrations of NO2, SO2, CO, O-3 PM2.5 and microclimate parameters (temperature and relative humidity) were monitored. Monitoring results showed lower concentrations indoor than outdoor, I/O ratios fits in the interval [0.32; 0.81] except CO with an I/O ratio situated close to the value 1. Averages concentrations were below those recommended by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) for air chemical pollutants measured inside the museum, except ozone concentration whose average is in the hot season slightly above the recommended limit but below the lower intervention limit, 50 mu g/m(3). Microclimate parameter values also fall into a range that implies reduced risk for various objects and books according to ASHRAE; diurnal variations of microclimate parameters do not represent a danger for the exhibits in the museum, also. Analyzing the information obtained by monitoring indoor air quality and statistical interpretation of these data (I/O ratios, diagrams, Spearman correlation analysis) we can say that the air inside Hangar 1 and microclimate conditions provided do not raise major problems for long-term conservation of the exhibits in the museum and do not require additional measures in terms of air quality and microclimate parameters.

A big number of studies prove that there is a strong relation between the quality of indoor air in office environments and the health and productivity of people who work in these environments. The paper presents the results of a sampling campaign conducted in the autumn of 2014 in an office building in Bucharest, located in an area characterised by a low level of pollution, in order to determine the concentrations of PAHs and phenols from particulate matter. Parallel samplings have being conducted both indoor and outdoor (I/O): in an office, a smoking place and outside the building. The highest concentrations of particulate matter were found in outdoor air, 89.41 +/- 40.44 mu g/m(3); at the semi-opened smoking place the concentration was 70.89 +/- 26.24m/m(3), and inside the office, 45.89 +/- 19.65 g/m(3). The average I/O ratio was 0.53, indicating a good isolation of the building against particulate matter infiltration from outdoor and the absence of indoor sources of particulate matter. In samples taken from outdoor and from the smoking place have been identified a number of 13 PAHs with chrysene and benzo(a)pyrene being the most abundant and m, p-cresol and 2-3 xylenol among phenols. The results indicated that smoking places can have a big impact on indoor air quality if they are not properly located in order to avoid the infiltration of PAHs inside offices.

The determination of elements content in the fruiting bodies of mushrooms is essential in dietary intake studies, because this aliment is used in the diet of many countries. In this study the contents of several elements, including Mn, Fe, Cu, and Zn, in cap and stipe of ten edible mushroom species, were determinate by using ICP-MS technique. These edible mushrooms species were collected from four sites of Dambovita County, Romania. After this study it was observed that mushrooms accumulate elements in different levels, in caps and stipes, depending on its species. It is well known that some elements cause a metal stress in the cells, resulting in the formation of ROS, survival of the microorganism in this stress is attributed to the induced biosynthesis of enzymes responsible for antioxidant defense.

This study presents the results from two tests performed in one of Bucharest's main crossroads during the summer and winter of 2010. These tests monitored the air pollution based on PM 2.5 and PM 10 particulate matter as well as the total suspended particles (TSP) and polycyclic aromatic hydrocarbons (PAH). The PM2.5 concentration varied between 21.9 and 56.6 mu g/m(3), the higher concentrations being found during the winter. The PM2.5 concentration contributed 92% of the PM10 concentration in the winter and 79% in the summer. The relatively high molecular weight PAHs (4-6 rings), which are typical of traffic emissions, were found in all three particulate matter fractions. The most abundant PAH, benzo[k]fluoranthene, was found in PM2.5 between 1.96 - 22.5 ng/m(3). Based on the results, we showed that the air pollution level with particulate matter PM 2.5 and PAH detected in the ruttier traffic conditions is frequently above the legal limit having a potential harmful effect on the population.

This review presents some of the most recent aspects related to antioxidants and the basic kinetic models of inhibited autoxidation and analyzes the chemical principles of antioxidant capacity assays. Taking into account the reactions involved, in the antioxidant activity determinations, the assays can be classified into two main types: hydrogen atom transfer reactions and electron transfer. This review focuses on analytical methods used for antioxidant activity assay, published in the period 2009-2014.

To gain new insight into the antimicrobial potential of Ailanthus altissima Swingle, ethanol leaf extracts were evaluated for the antifungal effects against the model yeast Saccharomyces cerevisae. The extracts inhibited the yeast growth in a dose-dependent manner, and this effect could be augmented by heat shock, exposure to visible light or exposure to high concentrations of Ca2+. Using transgenic yeast cells expressing the Ca2+-dependent photoprotein, aequorin, it was found that the leaf extracts induced cytosolic Ca2+ elevation. Experiments on yeast mutants with defects in Ca2+ transport demonstrated that the cytotoxicity of the A. altissima leaf extracts (AaLEs) was mediated by transient pulses of Ca2+ ions which were released into the cytosol predominantly from the vacuole. The investigation of the antifungal synergies involving AaLEs may contribute to the development of optimal and safe combination therapies for the treatment of drug-resistant fungal infections.

The influence of some important experimental variables on the analytical signals of a flow injection analysis (FIA) method with chemiluminescence (CL) detection (FIA-CL) based on the use of the system luminol/Co(II)/EDTA/H2O2 was reported. The principle and application of the method for the determination of total antioxidant capacity (TAC) of different samples were described in several papers. However further studies on the method are necessary to avoid important errors in determinations. The following experimental variables of the FIA-CL method were studied and optimized: the flow rates of the reagents, the ratio of Co(II)/EDTA in the reagents, the injected sample volume, the concentrations of ethanol, methanol and acetone in the analyzed samples and the concentration of ethanol in the carrier. A calibration graph in different experimental conditions was traced by using caffeic acid as a standard. The optimized method was applied for total antioxidant capacity determination of several ethanolic extracts from nine Lamiaceae species.

phenolic acids (gallic, caffeic, chlorogenic, vanillic, syringic, ferrulic, rosmarinic, trans-2-hydroxycinamic) are common in citric seeds. Concentrations of these compounds are modified as a function of fruit matureness (and implicitly of the seeds) so that when ripe the fruit seeds contain large amount of antioxidants [10]. The polyphenolic composition of citrus seed compounds differs a great deal from one species to other but 7-O-glicozoflavones prevail in all of them. Different parts of the fruits (seeds, pulp, peel) have different polyphenolic composition. As example, eriocitrin and hesperidin prevail in lemon seeds, while neoeriocitrin, narginin and neohesperidin are mostly present in the peel [12]. Although naginin is found in the peel as well as seeds, it is absent in fruit pulp. Grape seeds contain approximately 7% polyphenols [13] among which an important part of is represented by proantocianides. The later form a group of bioflavonoids,

Instrumentation and operational FIA modes in industrial analysis and the advantages of the application of this technique to industrial process monitoring were discussed. Some relevant examples for the applications of FIA for industrial processes, biotechnological processes, food and beverage industry, and wastewater monitoring were presented.