Research on natural compounds is increasingly focused on their effects on human health. In this study, we were interested in the evaluation of nutritional value expressed as content of total phenolic compounds and antioxidant capacity of new apricot (Prunus armeniaca L.) genotypes resistant against Plum pox virus (PPV) cultivated on Department of Fruit Growing of Mendel University in Brno. Fruits of twenty one apricot genotypes were collected at the onset of consumption ripeness. Antioxidant capacities of the genotypes were determined spectrometrically using DPPH• (1,1-diphenyl-2-picryl-hydrazyl free radicals) scavenging test, TEAC (Trolox Equivalent Antioxidant Capacity), and FRAP (Ferric Reducing Antioxidant Power)methods. The highest antioxidant capacities were determined in the genotypes LE-3228 and LE-2527, the lowest ones in the LE-985 and LE-994 genotypes. Moreover, close correlation (r = 0.964) was determined between the TEAC and DPPH assays. Based on the antioxidant capacity and total polyphenols content, a clump analysis dendrogram of the monitored apricot genotypes was constructed. In addition, we optimized high performance liquid chromatography coupled with tandem electrochemical and spectrometric detection and determined phenolic profile consisting of the following fifteen phenolic compounds: gallic acid, 4-aminobenzoic acid, chlorogenic acid, ferulic acid, caffeic acid, procatechin, salicylic acid, p-coumaric acid, the flavonols quercetin and quercitrin, the flavonol glycoside rutin, resveratrol, vanillin, and the isomers epicatechin, (–)- and (+)- catechin.

The study of changes of nutritional value of fruit during the ripening process can help estimate the optimal date for fruit harvesting to achieve the best quality for direct consumption and further utilization. The aim of this study was to monitor the changes of chemical composition of medlar fruit (Mespilus germanica L.) measured at five various ripening stages including 134, 144, 154, 164 and 174 days after full bloom (DAFB). Fruits were analyzed and ascorbic acid (AA) and total phenolic compound content with respect to the total antioxidant activity were determined. In addition, selected micronutrients and macronutrients were monitored. The results of our experiments demonstrate that ascorbic acid, total phenolic compound content and total antioxidant activity decreased significantly with increasing time of ripeness. The decreasing tendency in potassium, calcium and magnesium contents during the ripening stages was also determined. During the ripening period, the content of all micronutrients as well as phosphorus and sodium was balanced, with no statistically significant differences between the monitored ripening stages, which can be considered as a positive fact with respect to ideal consumption quality of fruit.

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Plum pox virus (sharka; PPV) can cause severe crop loss in economically important Prunus species such as peach, plum, apricot, and cherry. Of these species, certain apricot cultivars ('Stark Early Orange', 'Goldrich', 'Harlayne') display significant levels of resistance to the disease and are the genetic substrate for studies of several xlaboratories working cooperatively to genetically characterize and mark the resistance locus or loci for marker-assisted breeding. The goals of the work presented in this communication are the characterization of the genetics of PPV resistance in 'Stark Early Orange' and the development of co-dominant molecular markers for marker-assisted selection (MAS) in PPV resistance breeding. We present the first genetic linkage map for an apricot backcross population of 'Stark Early Orange' and the susceptible cultivar 'Vestar' that segregates for resistance to PPV. This map is comprised of 357 loci (330 amplified fragment length polymorphisms (AFLPs), 26 simple sequence repeats (SSRs), and 1 morphological marker for PPV resistance) assigned to eight linkage groups. Twentytwo of the mapped SSRs are shared in common with genetic reference map for Prunus (T × E; Joobeur et al. 1998) and anchor our apricot map to the general Prunus map. A PPV resistance locus was mapped in linkage group 1 and four AFLP markers segregating with the PPV resistance trait, identified through bulk segregant analysis, facilitated the development of SSRs in this region.

In this study, biochemical profile of fruits of 9 Sorbus genotypes was analyzed. The content of total sugars ranged from 69.7 g/kg ('Titan') to 217.5 g/kg (Sorbus torminalis) and total organic acids from 17.7 g/kg ('Businka') to 40.2 g/kg (S. torminalis). The highest content of total anthocyanins had 'Burka' (871 mg/kg FW) and 'Businka' (856 mg/kg FW). Quercetin derivatives represented more than 95% of total flavonols. 'Alaja krupnaja' had 3.5- to 29-fold higher rutin content than other analyzed genotypes. S. torminalis fruits had the greatest diversity of isorhamnetin and kaempferol derivatives. Chlorogenic acid was the major hydroxycinnamic acid and its share was 33% to 73% of total analyzed hydoxycinnamic acid derivatives. The richest in chlorogenic acid were 'Krasavica' and 'Alaja krupnaja' fruits. Cultivar 'Businka' had the highest content of epicatechin (40.7 mg/kg) and neochlorogenic acid (1061 mg/kg). Different procyanidin oligomers were detected among flavanols in Sorbus fruits. The highest content of total flavanols was measured in 'Alaja Krupnaja' fruits. Cultivars 'Krasavica' (84.5 mg/kg) and 'Burka' (85.1 mg/kg) had 1.2- to 6.9-fold higher amount of total carotenoids. 'Businka' was highlighted as the richest in total tannin and phenolic contents (3768 mg GAE/kg) and consequently, it had the highest antioxidant activity (57.6 mM TE/kg FW). Being abundant in polyphenolics, some extracts of Sorbus genotypes, for example, 'Businka,' 'Burka,' and 'Alaja krupnaja' could serve as valuable resource of bioactive compounds to food and pharmaceutical industries.