Raspberry leaves are a source of carotenoids and polyphenols, including ellagic acid and salicylic acid. The results of scientific research suggest that they have potential pro-health properties that contribute to human health. The aim of this study was to determine the polyphenolic and carotenoid profiles in the leaves of selected raspberry cultivars and their in vitro activity. The second aim was to determine the impact of organic and conventional farm management on the polyphenol, carotenoid, and chlorophyll contents in different raspberry cultivars: ‘Polana’, ‘Polka’, ‘Tulameen’, ‘Laszka’ and ‘Glen Ample’. Compared with conventional raspberry leaves, organic raspberry leaves were characterized by a significantly higher content of dry matter, total polyphenols, total phenolic acids, chlorogenic acid, caffeic acid, salicylic acid and quercetin-3-O-rutinoside; moreover, the organic leaves were characterized by higher antioxidant activity. Among examined cultivars, ‘Polka’ c. was characterized by the highest antioxidant status. However, raspberry leaves from conventional farms contained more total carotenoids, violaxanthin, alpha-carotene, beta-carotene, total chlorophyll and individual forms of chlorophylls: a and b.
1 April 2020 in Journal of Food Composition and Analysis
The aim of this study was to evaluate and compare the content of a number of bioactive compounds and antioxidant activity of fruits of selected local and commercial sweet cherry (Prunus avium L.) cultivars. The experiment showed that the selected cultivars of sweet cherries differ significantly in the content of polyphenolic compounds and carotenoids. The fruits of commercial sweet cherry cultivars were, on average, richer in polyphenols (the sum of phenolic compounds determined chromatographically), flavonoids, as well as anthocyanins and were characterized by higher antioxidant activity when compared to the local, traditional cultivars. In the group of the traditional sweet cherry cultivars, particular attention could be paid to Black Late cv., showing the highest antioxidant activity of fruits. In the group of commercial sweet cherry cultivars, Cordia and Sylvia fruits could be recognized as being rich in bioactive compounds with high antioxidant activity. Yellow skin cultivars were characterized by the highest concentrations of carotenoids. Strong positive correlations between the identified bioactive compounds and antioxidant activity of fruits were also found. Although different cultivars of sweet cherries show a high variability in phenolics and carotenoids profiles as well as in the antioxidant activity of fruits, they all should be, similarly to other types of cherries, recognized as a rich source of bioactive compounds with an antioxidant potential.
Anthocyanins are widely distributed secondary metabolites that play an essential role in skin pigmentation of many plant organs and microorganisms. Anthocyanins have been associated with a wide range of biological and pharmacological properties. They are also effective agents in the prevention and treatment of many chronic diseases. Berries are particularly abundant in these compounds; therefore, their dietary intake has health-promoting effects. The aim of this study was to identify and determine the anthocyanin content in selected species and cultivars of berry fruits, such as raspberry, blackberry, red currant, blackcurrant, and highbush blueberry, widely consumed by Europeans. The concentrations of anthocyanins were determined by HPLC, identifying individual compounds: cyanidin-3-O-glucoside, pelargonidin-3-O-glucoside, delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, cyanidin-3-O-rutinoside, delphinidin-3-O-galactoside, cyanidin-3-O-galactoside, and malvidin-3-O-galactoside. The experimental data showed that the selected species and cultivars of berry fruits differ significantly in the contents of anthocyanins. Among all species tested, blackberry and blackcurrant were characterized significantly by the highest content of anthocyanins (sum), while the lowest content was found in red currant fruits. Additionally, the content of individual anthocyanin compounds in particular species and cultivars was also different. Considering the high content of anthocyanins and their potential positive impact on human health and protection against disease, berries should be part of healthy nutrition.
The apple (Malus domestica Borkh.) is one of the most widely cultivated temperate fruits globally, gaining scientific interest as a rich source of antioxidants with a demonstrated beneficial human health impact. Since a growing number of consumers are increasingly seeking safe and healthy food options, alternative fruit production systems such as organic farming, and their potential to provide safe and nutritious foods, have been gaining increasing attention in the last decades. The aim of the presented study was, therefore, to analyse and to compare the concentrations of selected health-promoting antioxidants, such as phenolic acids, flavonols, and vitamin C, in fruits of three apple cultivars (Champion, Gala, and Idared) grown in conventional and certified organic orchards in Poland. All analyses were performed using the high-performance liquid chromatography (HPLC) method. Organic apples tested within the study, compared to the conventionally grown ones, were characterised by significantly higher concentrations of phenolic acids (av. >31%) and flavonols (av. >66%) with the identified differences being consistent in all three cultivars and two seasons. The greatest production system effect was observed in the case of Idared. Significant cultivar and production season effects on the concentration of the measured fruit phenolics, with strong interactions between the two factors, were also identified. Vitamin C content in the fruits was strongly dependent on the year-to-year differences in the fruit growing conditions. The study suggests that the organic production system has a potential to provide apple fruits rich in selected health-promoting phenolic antioxidants.