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The purpose of this paper is to determine the total phenol content (TP) and total flavonoid content (TF) fluctuations in different infusions of lemon verbena. Dried leaves were harvested in May, July and October and prepared at various soaking times (5-20 min).

The Folin-Ciocalteu method was used to determine TP, while TF was determined by the aluminum chloride method.

According to the results, the July harvest had the highest content of TP and TF, followed by May and October. Temperature and soaking time play a role in the proportion of released phenols and flavonoids (p < 0.05), whereas the content in continuous infusion is higher than infusion (without boiling) .TP and TF in infusion increase until 20 min, while concentration is convergent in continuous infusion after10 minutes, where no significant difference is seen. In the flowering stage, TP is close in comparison with the vegetative stage.

Harvest time plays a role in the content, so it is best to prepare infusion from lemon verbena before the flowering period, when people drink it, as the results show. According to the authors’ knowledge, this is the first work that studied the variation in phenol and flavonoid content during different stages of growth with soaking time in drenched lemon verbena leaves.

The purpose of this paper is to determine the antioxidant properties and phenol content of methanolic extracts of six white varieties and six purple/brown varieties of Indian rice and to find some relationship between the antioxidant properties, phenolic content in the varieties analyzed.

Methanolic extracts of different rice varieties were analyzed for their superoxide radical scavenging activity, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity, total antioxidant capacity, reducing power and ferrous ion chelating properties. The extracts were analyzed for determination of total phenol content, anthocyanin content, oryzanol content. Phenolic acids were determined by HPLC.

All the rice varieties (white and purple/brown) showed activity in a dose‐dependent manner. Free phenolic acids, e.g. protocatechuic acid, caffeic acid, vanillic acid, p‐coumaric acid (PCA), ferulic acid and sinapic acid and the phenolic aldehyde vanillin could be detected in all the rice samples analyzed. No relationship could be established between activity and metabolite content. Principal component analysis and classification shows that superoxide radical scavenging activity, total phenolic acid, protocatechuic acid and ferulic acid are the components to differentiate the varieties from each other.

Little work has been done on the antioxidant activity of white rice. The authors report superoxide radical scavenging activity, DPPH radical scavenging activity, total antioxidant activity, reducing power and ferrous ion chelating properties and phenolic contents of six white varieties and six purple/brown varieties of Indian rice. Free phenolic acids like protocatechuic acid, caffeic acid, vanillic acid, PCA, ferulic acid and sinapic acid are reported from all the 12 varieties of rice.

The main purpose of this study is to create a complete physico‐chemical characterisation of Romanian heather honey.

A total of 30 samples of heather honey were harvested from three different geographical areas (Fântânele, Călăţele, Mărişel) from Transylvania region (Romania). This study contains a complete characterization of heather honey regarding its physico‐chemical composition, total phenols content, flavonoids content, antioxidant activity (expressed as radical scavenging activity – RSA) and micro‐ and macroelements content.

The results obtained for the total phenols content and total flavonoids demonstrate that honey samples have good bioactive properties and the antioxidant activities are similar to those of dark honeys. Heather honeys normally have a high content of minerals, having their origin in soil. All quantified minerals in heather honey presented values higher that those reported for other types of honey.

Heather honey is a very important type of honey for consumers, which due to its features has a high price on the local market. This study provides the main analytical methods for honey quality determination, which is very important for the students.

For the first time in Romania a complete study of heather honey was done.

Fenugreek (Trigonella foenum-graecum) leaves have received an enormous demand due to their uses in traditional Indian preparations. It is a green leafy vegetable that is highly perishable in nature, due to high respiration rate; consequently, sensory as well as nutrient loss occurs at a very high rate. The aim of this research was to enhance the shelf life of fresh fenugreek leaves under modified atmosphere and determine the effect of different physiochemical parameters on storability of fenugreek leaves.

Fresh fenugreek leaves were stored in polypropylene (PP) film package under four different treatments, viz., T1: perforated (one perforation), T2: perforated (two perforation, 0.3 mm each), T3: non-perforated and T4: control sample. The control samples were kept in packages under ambient conditions. All packed samples were stored at 15°C temperature and 75 per cent relative humidity (RH). The quality was determined on the basis of retention of pigments, flavonoids, antioxidants, ascorbic acid and total phenols. The sensory evaluation of the stored samples was also carried out at regular intervals.

The results of this study indicated that the quality of fresh fenugreek leaves in PP (34 μm) non-perforated package (T3) stored at 15°C and 75 per cent RH was superior to those packed under other treatments on the basis of color retention, β-carotene, ascorbic acid, 2,2-diphenyl-1-picrylhydrazyl, total phenols and overall acceptability. The produce could be safely stored for 9 days without any adverse effect on bioactive compounds.

Factors leading to deterioration of quality of fresh fenugreek leaves like pigments and phenolic content were largely influenced by in-pack gaseous atmosphere inside the polymeric film packages. Modified atmosphere packaging with different treatments for enhancing shelf life and retention of bioactive compound of fenugreek was carried out in the work.

Due to the importance attributed to the phenolic compounds present in cocoa samples for their beneficial effects on health, the purpose of this paper was to analyze four samples of organically and conventionally cultivated cocoa from the south area of Bahia for their composition of phenolics, flavonoids and their antioxidant activity.

Non‐fermented beans, fermented beans, roasted nibs and cocoa liquor were analyzed using spectrophotometry.

In general, the samples that contained a higher level of phenolics and flavonoids were the roasted nibs and the non‐fermented samples in both cultivation systems. The fermented beans and the liquor contained a lower level.

The relationship between the concentration of total phenols and the capacity to “mop up” free radicals from the cocoa extracts appears to be highly significant. The extracts with a higher concentration of phenols also show higher antioxidant activity (non‐fermented beans extracts and organically and conventionally cultivated nibs).

This work brings an important contribution in the field of agriculture at a time when organic systems of cultivation are an alternative to the conventional system and that pollutes the environment and produces food that contains quantities of chemical contaminants that can damage the health of the consumer. The comparison in phenolic compounds content, flavonoids and antioxidant activity in organic and conventional systems is original and of great importance, showing that the ecological cropping systems are less harmful to the environment and promote improvements to the chemical composition of foods.

This paper seeks to demonstrate a functional beverage incorporating pine bark which is an unutilized forestry waste, determine in vitro release kinetics of enriched beverages, and antioxidant activities, besides assessing their shelf stabilities.

Orange juice was enriched with Pinus brutia, Pinus pinea bark extracts, Pycnogenol^®. In vitro release kinetics was determined in pH 1.2 and pH 7.4. Ascorbic acid content, pH, titratable acidity, and colorimetric analyses were analyzed monthly for eight months to determine shelf life. Additionally, total phenol contents and radical scavenging activities were analyzed. Subsequently a consumer acceptance test was conducted among 200 participants.

The release of all extracts in orange juices in pH 1.2 were slower than pH 7.4. The release results were fitted to Higuchi square root of time kinetic model with high determination coefficients. Although total titratable acidity values were in agreement with the trend of minor pH changes, prominent losses in antioxidant capacities, ascorbic acid contents and color were observed for the last two months suggesting a shelf life of six months. Female participants and young people had a greater tendency to consume such a beverage. Health concerns and flavor were the primary factors affecting their purchasing decisions.

Findings of the study demonstrated the effects of fortification with a plant‐based extract as a substitute to the present practice of fortifying beverages with vitamins and minerals for a potential future market.

The paper shows that juices fortified with pine bark extracts show higher antioxidant capacities and ascorbic acid contents compared to the control, thereby providing improved functionality.

The purpose of this paper is to evaluate both nutrient and phytochemical content of Swiss chard grown under different fertilization and irrigation treatments and the effect of these treatments on the tested parameters.

Samples of fresh Swiss chard were collected from the experimental field of Ljeskopolje, Montenegro, where chard was grown under different fertilization and irrigation treatments. Swiss chard samples were analyzed for nutritional and antioxidant parameters.

In this study, the authors found that 100 g of Swiss chard is a good source of total chlorophyll (47.13 mg), carotenoids (9.85 mg), minerals as well as vitamin C (26.88 mg) expressed as mean values. Total phenol and flavonoid compounds content were (138.59 µg gallic acid equivalent (GAE) and 11.91 µg catechin equivalent (CAE) per mg of water extract, respectively), also expressed as mean values. The total antioxidant capacity (IC50 values) determined by 1,1-diphenyl-2-picrylhydrazyl assay ranged from 2.93 to 4.44 mg/mL of aquatic water extract. Different fertilization regimes affected the following parameters: phosphorous, protein content, chlorophyll a, chlorophyll b and vitamin C (p<0.05), while different irrigation regimes did not have any effect on the tested parameters (p>0.05), while interaction effect between fertilization and irrigation was found only for sodium and copper (p<0.05).

Swiss chard produced in Montenegro on a sandy clay loam soil with acid reaction contains appreciable amount of minerals, crude fibers, vitamin C, chlorophylls, carotenoids and polyphenols. The nutrient and phytochemical content of chard is equal or superior to other green leafy vegetables which are considered as functional food. It was identified as a potentially rich source of essential nutrients and phytochemical compounds. The promotion of higher consumption and production of Swiss chard may represent a natural and sustainable alternative for improving human health.

The antioxidant characteristics of fruits can be attributed to their contents of polyphenols and vitamins. Because of the interest in the role of antioxidants in human health, the purpose of this paper is to examine the major compounds associated with antioxidant activity, namely total phenolic and vitamin C contents, of some regularly cultivated and consumed fruits in Iran.

In total, 66 fruits from 22 families were chosen for this study. Terbium sensitized fluorescence assay and spectrophotometric method were used to determine total polyphenol and vitamin C contents respectively. The ANOVA with Tukey post‐hoc test was used for statistical analyses.

The total mean polyphenol content of fruits was 4.93 ± 2.86 mg QE/100 g that were ranging from 0.8 ± 0.05 to 11.94 ± 0.02 mg QE/100 g with the lowest amount obtained for pear and the highest amount detected in black grape. The polyphenol contents of black grape, sourcherry and pomegranate were significantly higher than those of other fruits (p < 0.001). The total mean vitamin C content of fresh fruits was 18.34 ± 9.77 mg/100 g that were ranging from 57.38 ± 0.02 (strawberry) to 11.44 ± 0.02 (melon) mg/100 g. The vitamin C contents of strawberry was significantly higher than all other fruits (p < 0.001). Despite the differences in the polyphenol and vitamin C contents of various fruits, as a good source of nutritious compounds and functional foods, they can be effective in enhancing health status.

This paper is believed to be the only one which provides information about the polyphenol and vitamin C contents of Iranian fruits. Also, the polyphenol content was measured by using a newly‐developed method.

This paper aims to study the effect of cooking and food additives, such as lemon juice and vinegar, on phenols and flavonoids contents and antioxidant activity of purslane.

The Folin–Ciocalteu method was used to determine total phenols content (TP), while total flavonoid content (TF) was determined by the aluminum chloride method. Two methods were used for determination of antioxidant activity: DPPH (1, 1-diphenyl-2-picrylhydrazyl) assay to determine radical scavenging activity, and ferric-reducing antioxidant power (FRAP) to measure the reducing power.

According to the results, leafs had higher values of TP, TF and antioxidant activity than aerial parts. Both lemon juice and vinegar retracted antioxidant properties of leafs. TP and TF of leaves showed deterioration after treatment with lemon by 58% and 21.8%, respectively, and FRAP and radical scavenging activity decreased by 75.8% and 74.5%, respectively (p < 0.001). Also, TP, TF, FRAP and DPPH radical scavenging activity decreased in leaves by 82.2%, 30.5%, 87.8% and 90.9%, respectively, after treatment of leaves with vinegar. TF increased after cooking in studied parts, where no significant statistical difference was observed in TP and antioxidant activity (DPPH assay and FRAP) of cooked aerial parts. Adding lemon juice after cooking increased antioxidant properties of purslane (p < 0.001).

Purslane has antioxidant activity because it is rich in polyphenols and flavonoids. Effects of food additives and cooking were studied using different measurements. According to the authors’ knowledge, this is the first work that studied the effect of food additives on antioxidant properties of purslane.

Bambara groundnut is a hard-to-cook grain and this has limited its utilisation to some extent. However, the grain is a good source of phytochemicals with antioxidant properties. This study investigated the total phenol content, antioxidant, anti-inflammatory and anti-microbial potentials of hot-water extract of four Bambara groundnuts differentiated by their seed coats (cream, black, maroon and brown).

Bambara grains were heated in water at a ratio 1:20 (w/v) and the grains brought to boiling in a controlled water bath. As soon as boiling started, the temperature was reduced to 90 °C to reduce the evaporation rate. The extracts were withdrawn within 30 min, which was chosen from a preliminary study where beyond this time, the extract was drying off and the amount of solution obtained was not sufficient for the initial run. Grain colour and composition and antioxidant, antimicrobial and anti-inflammatory properties of the extract were determined using standard methods.

Protein (20.57–26.31%) and carbohydrate (55.43–61.09%) were the major components of the grain. Grain type and boiling time generally affected the total phenolic content of the extract. Cream Bambara displayed substantially lower total phenolic content at all boiling times compared with the maroon, brown and black Bambara groundnuts. The total flavonoid contents and total phenolic contents of the Bambara groundnut extracts were dependent on the boiling time and type of grain. The extracts showed no activity against Candida albicans, but the maroon coat Bambara demonstrated a peak inhibition of 6.00 mm against Escherichia coli. The total phenolic, flavonoid contents and the antioxidant properties of the grains generally followed the order Maroon > Black > Brown.

This study has demonstrated the possibility of promoting the use of Bambara groundnut beyond the current level of usage by using simple processing method of boiling to extract phytochemicals with medicinal properties.