Apricot fruits are a favorite for consumption; however, their kernels are a rich source of nutritionally interesting substances, too. Nevertheless, in processing of apricots, the kernels remain often unused. In this study, 32 cultivars of different origin were analyzed for their protein content and content of secondary metabolites (phenolics and flavonoids). The weight and taste of kernels were assessed and these data were summarized for an evaluation of the attractiveness of the studied apricot kernels. Results showed that the protein content of kernels ranged from 14.56% to 28.77% and did not depend on the origin or weight of kernel, or taste. In addition, total phenolic (63.5–1277.3 mg GAE/100 g DW) and total flavonoid (0–153.1 mg CE/100 g DW) contents and antioxidant capacity (483.4–2348.4 mg TE/100 g DW) were measured in kernels. In conclusion, the Czech hybrids LE-5959, LE-5500 and French cultivar Koolgat are prospective for kernel processing and consumption because of their high protein content and sweet taste. Hybrid LI-3-6, originating in China, showed high protein content as well but because of bitter taste could be useful rather in medicine.

The apricot is attractive for several reasons, with the most important being the harvest period and the significant amount of contained substances that positively affect human health. This report discusses the identification and quantification of phenolic substances in 15 selected apricots. The following 14 phenolic compounds were identified: 4aminobenzoic acid, chlorogenic acid, cinnamic acid, flavonols quercetin and quercitrin, isoquercetin (quercetin-3-β-D-glucoside), rutin, resveratrol, vanillin, phloridzin, phloretin, epicatechin, catechin, and transpiceid. Significant amounts of phytochemicals found in apricot fruits are chlorogenic acid [0.69–21.94 mg/100 g fresh weight (FW)], catechin (0.55–10.75 mg/100 g FW), epicatechin (0.04–13.52 mg/100 g FW), and rutin (1.49–20.44 mg/100 g FW). Rutin and chlorogenic acid were the dominant compounds found in the studied set of cultivars. Furthermore, other important analytical properties of fruits (total acids, vitamin C, total content of phenolic substances, flavonoids, antioxidant capacity, and carotenoids) were also determined.

Peaches (Prunus persica L.) are a popular and sought-after dessert fruit. This is mainly due to their flavour, aroma, attractive appearance, and high content of substances that play an important role in human nutrition. The present study was carried out to determine some important analytical properties (sugars/sucrose, glucose, fructose and sorbitol), total acid, total phenolics, flavonoids, antioxidant capacity, carotenoids and anthocyanins of 34 selected peach varieties. The analyses are also complemented by colorimetric measurements of peach skin colour using CIELAB and other chromatic parameters. The results show, for example, that all peach varieties are good sources of phenolic compounds (9.43–577 mg gallic acid equivalent (GAE).100 g−1), flavonoids (1.12–95.1 mg catechin equivalent (CAE).100 g−1), and antioxidant capacity (136–462 mg Trolox equivalent (TE).100 g−1).

Various treatments are carried out in order to extend both the shelf life and storage life of fresh fruit and vegetables after harvest and among them non-toxic for humans, environmentally and economically friendly alternative treatments are gained more importance. In the current study, methyl jasmonate (MeJA), cytokinin, and lavender oil which are eco-friendly and safe for human health were applied on apricot fruit. The treated fruit were stored at 0 °C and 90–95% relative humidity for 25 days and catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX) enzyme activities and lipid peroxidation of apricots after treatments were studied. According to the findings obtained from the study, it was observed that 5 ppm cytokinin and 1000 ppm lavender oil treatments of apricot fruit gave better APX and CAT enzyme activity, respectively. In addition, better SOD enzyme activity in fruit was obtained with MeJA + lavender oil treatments. As a result, it can be emphasized that the product quality of apricot fruit is preserved as both the eco-friendly application of MeJA, cytokinin, and lavender oil separately from each other and the treatment of combinations between these compounds activate the enzymatic antioxidant defense systems of apricot fruit after harvest.

Fruits are a rich source of vitamins and antioxidants and their consumption is important for human health. Anthocyanins contribute to antioxidant characteristics in colourful fruits, especially with blue, purple and red tones of colour. The aim of this work was to study the correlation between anthocyanin content and the external colour of plums. European (Prunus domestica) and Asian (Prunus salicina) plum plum and the apricot (Prunus armeniaca) -pluotswere chosen for this investigation. Results showed that total anthocyanin content in fruits ranged between 0.2 and 217.0 mg kg -1 fresh weight (FW) among varieties. High anthocyanin values were measured in cultivars derived from the Japanese plums 'Black Amber' and 'Black Star', however, the highest values were surprisingly measured in the pluot 'Flavorich pluot ® '. Anthocyanin values for European plum cul--1 FW. The colour of the fruit was measured using the colour scale set by the Commission Internationale de L'Eclairage (CIELAB) and from chromatic parameters L*, a*, b* the chroma parameter (C * ab ), hue angle (h°a b )and colour index of red grapes (CIRG) were calculated. Correlation of the colour parameters with the anthocyanin content in plum fruits was determined and it was found that CIRG is a suitable comparison parameter with exponential positive correlation to anthocyanin content. The present work highlights that colour parameters, especially CIRG, are a good tent with using founded regression function. This method could be used to obtain an overview about healthy substances of fruit without its destruction or using chemical analyses.