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The genus Pleurotus is the third most commonly produced edible fungi in the world. In addition, species of genus Pleurotus have functional properties such as anticancer, antiviral, antimicrobial, anti-inflammatory, and antioxidant activities, which are mainly attributed to phenolic compounds. For these reasons, this study evaluated the productivity and antioxidant activity (AA) of 2 wild strains (white and pink), 2 reconstituted strains (called "BB" and "RR"), and 4 hybrid strains (H1, H2, H3, and H4) of P. djamor from monokaryotic components (neohaplonts). The results showed that the white wild-type strain and the reconstituted strains exhibited the best production potential, expressed as biological efficiency and mycelial growth rate. The carpophores of hybrid strains H1 and H3 had the greatest AA, as evaluated with DPPH radical scavenging and reducing power assays, respectively. The H3 strain had the highest total phenol (TP) content. Pearson correlations led us to conclude that the mycelial growth rate has a regular inverse correlation with TP and a regular direct correlation with AA of methanolic extracts from carpophores and myce-lia. This is, to our knowledge, the first report in the literature about the effect of Pleurotus strain hybridization through a chemical de-dikaryotization process on TP content.

The food industry is becoming more specialized and processing methods are continuously being developed to meet consumer needs. Consumers demand products that are safe and preferably free of synthetic additives. These additives are associated with health effects, in most cases without reasonable justification. Consequently, consumers are looking for clearly labelled products that guarantee the absence of synthetic additives. This has led to the need to search for natural additives, which the food industry claims arenatural antioxidant preservatives. The sources of natural antioxidants can be extremely varied, because practically all plants contain antioxidants that allow them to protect themselves from solar radiation and pests, as well as to regulate the production of chemical energy. However, the best alternatives for the food industry are fruits and spices, because they are already foods themselves. This article will describe fruits and spices considered as important sources of phenolic antioxidants. The main medicinal properties are related to phenolic compounds and their uses as additives, depending on their chemical structure.

Tomato is one of the principal crops worldwide due to its large consumption. In this work, biofertilization treatments, based on Bacillus licheniformis , with different nitrogen fertilization doses were investigated to improve the functional quality of tomato under greenhouse conditions. Treatments tested used nitrogen fertilization only (NF) or nitrogen combined with biofertilization (BF) with the following nitrogen doses: 0, 25, 50, 75 and 100% of the recommended nitrogen dose. The lycopene content increased with the nitrogen dose with the BF treatments resulting in lower lycopene contents in comparison with the NF counterparts. The contents of hydrophilic antioxidant compounds (vitamin C and total phenols), as well as antioxidant activity (DPPH scavenging capacity and FRAP) increased as the nitrogen dose was reduced. The biosynthesis of the hydrophilic antioxidant compounds appears to be an induced resistance mechanism caused by the nitrogen-deficiency stress. In addition, B. licheniformis had a positive net effect on the synthesis of flavonoids by the plant at a 75% nitrogen dose. A two-factorial ANOVA (nitrogen fertilizer dose × biofertilizer addition) evidenced that the greatest contribution of the nitrogen fertilizer dose was to the total phenols content and antioxidant activity, while the biofertilizer mainly contributed to the vitamin C and lycopene contents. In general, the content of antioxidant compounds was affected by the interaction of the two factors. Significantly, this is the first report about the combined effect of the nitrogen fertilization dose and biofertilization addition during tomato cultivation, on the content of antioxidant compounds in tomato fruits. [ABSTRACT FROM AUTHOR]

Abstract: A rotating tray drier was built and controlled for drying of tomato slices at different temperatures (45, 50 and 60 °C) and air velocities (0.6 and 1.2 m s−1) with and without tray rotation. Drying curves were fitted using the Page mathematical model. Effective diffusivities for the different drying conditions correlated well with the chemical composition variables; lycopene, ascorbic acid and total polyphenols (TPP). The effect of drying conditions over quality of dried tomato slices was evaluated by quantifying their contents of lycopene, ascorbic acid and TPP, and measuring their color and rehydration ratio. The best drying conditions were 60 °C drying temperature and 0.6 m s−1 air velocity with the use of tray rotation. These conditions minimized the degradation of lycopene (2.9%), ascorbic acid (17.3%) and TPP (2.1%) during drying. Tray rotation has a contribution on the a* color value, as well as on the lycopene and ascorbic acid concentrations (5% significance level). [Copyright &y& Elsevier]

Abstract: Annona diversifolia is a Central America native fruit which has become an important crop because of its tasty flavor, high pulp content, nutritional value and antioxidant properties. Color, crude protein, crude fat, crude fiber, ash, minerals, pH, titratable acidity, and carbohydrate contents were determinated in white, pink and deep pink varieties of A. diversifolia. Our results show that the three studied varieties of A. diversifolia could be considered as important sources of fiber, sugars, potassium and zinc. Color measuring was successfully used to objectively characterize the three A. diversifolia varieties, resulting in an excellent agreement with visual observations. The antioxidant activity also was determined and compared. An in vitro study was conducted in terms of vitamin C, total phenols, total flavonoids, and radical scavenging activity. A strong correlation between total polyphenols and radical scavenging activity was observed. This paper reports for the first time the total flavonoid content of Annona genus fruits. In addition, A. diversifolia extracts possessed greater radical scavenging activity and similar total polyphenol content compared to those of other Annona species reported elsewhere. [Copyright &y& Elsevier]