Amounts of total phenolics, anthocyanins, and ascorbic acid in 4 American cranberry varieties harvested at 4 stages of maturity were measured. The larger amount of phenolic compounds was found in berries of "Black Veil" cultivar (504 mg/100 g) at II stage of maturity. Significantly larger amounts of anthocyanins were determined in the overripe berries of the cultivars "Ben Lear" and "Black Veil." The amount of ascorbic acid in berries increased during ripening from I to III stage, and slightly decreased in the overripe berries. The biggest quantities of ascorbic acid were found in the ripe berries of "Ben Lear" cultivar (15.8 mg/100 g). The distribution of anthocyanins pigments was determined by HPLC-UV/MS in mature berries. The composition of individual anthocyanins in berries was quite similar in all the studied cranberry cultivars. While skins of cranberries are rich in anthocyanins and other phenolic compounds, the extracts of the by-products of cranberries juice-berry cakes, were analyzed and obtained results were compared with the properties of extracts made from whole berries. The anthocyanins and total phenolics content, radical scavenging activity, antimicrobial activity of the whole berries, and their press cakes extracts were measured. All investigated extracts from berries and their press cakes showed good radical scavenging activity and revealed antimicrobial properties. It was found that Bacillus cereus (ATCC 10876) and Micrococcus luteus (ATCC 9341) were the most sensitive among 10 tested Gram-negative and Gram-positive bacteria.

No abstract

In this study, the phytochemical composition (total phenolics, total anthocyanins and ellagitannins) and antimicrobial properties of raspberry fruit, pulp, and marc extracts obtained with 80% methanol and 80% acetone from different plant cultivars were assessed. The extracts were also subjected to screening for their possible antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) assay. The content of total phenolics in berry pulp extracts varied from 20.4 to 35.5, in whole berry extracts from 43.6 to 83.1 and in berry marc extracts from 93.9 to 163.8 mg/g (dry weight of extract). The content of ellagitannins was higher by 63-80% in raspberry marc extracts than in pulp extracts. Raspberry fruit, pulp and marc extracts isolated with aqueous acetone possessed stronger antimicrobial activity than the corresponding extracts isolated with aqueous methanol. The highest inhibitory effect against the investigated Gram-positive bacteria and yeast strains was shown by the extracts isolated from raspberry marc and containing the highest concentrations of total phenolics and ellagitannins.Keywords: raspberry extracts; antimicrobial properties; phenolics; ellagitannins En el presente estudio, se analizaron tanto la composicio´n fitoquı´mica -feno´licos totales, antocianinas totales y elagitaninos-, como las propiedades antimicrobianas del fruto, de la pulpa y de los extractos de bagazo de frambuesa, obtenidos a partir de distintas especies cultivadas que fueron aisladas en metanol al 80% y en acetona al 80%. Adema´s, se aplico´un proceso de cribado a los extractos por su posible actividad antioxidante, usa´ndose para ello la prueba DPPH. Se constato´que el contenido de feno´licos totales presento´variaciones: en los extractos de pulpa de frambuesa de 20,4 a 35,5 mg/g; en los extractos de frambuesas enteras de 43,6 a 83,1 mg/g; y, en los de extractos de bagazo de frambuesas, de 93,9 a 163,8 mg/g (peso en seco del extracto). Asimismo, se observo´que el contenido de elagitaninos fue entre 63% y 80% ma´s elevado en los extractos de bagazo de frambuesa que en los extractos de pulpa. El fruto, la pulpa y los extractos de bagazo de frambuesa que habı´an sido aislados con acetona acuosa presentaron una actividad antimicrobiana ma´s pronunciada que aquellos que lo fueron con metanol acuoso. El efecto inhibitorio ma´s fuerte contra bacteria gram positiva y contra cepas de levadura correspondio´a los extractos de bagazo de frambuesa aislados que contenı´an concentraciones ma´s elevadas de feno´licos y elagitaninos.

European cranberry is a berry plant rich in biologically active substances, making it valued by both the phyto-pharmaceutical and food industries. The aim of this study was to examine the accumulation of phenolic compounds and anthocyanins in berries of European cranberry and to assess their antibacterial activity. Material and methods. Different wild clones of European cranberry were investigated according to berry weight and the amounts of total phenolics and anthocyanins. Anthocyanin profiles of extracts were evaluated by HPLC, whereas the antimicrobial properties were determined by the agar well diffusion method. A strong negative correlation between berry weight and the amount of anthocyanins was found. The amount of total phenolics among different cranberry clones in the field collection ranged from 224.0 mg/100 g to 498.0 mg/100 g, and the amount of total anthocyanins ranged from 40.7 mg/100 g to 207.3 mg/100 g. Quantitative HPLC-UV analysis revealed six anthocyanins in the berries of European cranberry, among which the anthocyanin peonidin-3-galactoside was most prevalent. Conclusions. Investigation of the antimicrobial properties showed that European cranberry extracts inhibited the growth of wide range of human pathogenic bacteria, both gram-negative (Escherichia coli and Salmonella typhimurium) and gram-positive (Enterococcus faecalis, Listeria monocytogenes, Staphylococcus aureus, and Bacillus subtilis).

The value of fruits is determined by the quantity and variety of biologically active compounds they contain, and their benefits on human health. This work presents the first study of the biochemical composition and antibacterial activity of the new Japanese quince (JQ) cultivars ‘Darius’, ‘Rondo’, and ‘Rasa’ fruits. The total phenolic content (TPC) was determined using the Folin–Ciocalteu method and each compound was identified by HPLC High Performance Liquid Chromatography. The antimicrobial activity against three Gram-positive and three Gram-negative bacteria, and one yeast strain, was evaluated by the agar well diffusion method using three different concentrations. The free radical scavenging activity was determined using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid) methods and ranged from 99.1 to 115.9 μmolTE/100 g, and from 372 to 682 μmolTE/100 g, respectively. TPC ranged from 3906 to 4550 mgGAE/100 g, and five compounds, isoquercitrin, rutin, (+)-catechin, (–)-epicatechin, and chlorogenic acid were identified. All JQ extracts possessed antimicrobial activity against Gram-positive and Gram-negative bacteria, and Enterococcus faecalis (ATCC 29212) was the most sensitive strain. These results indicate that JQ fruits are a significant source of bio-compounds, which can enrich the diet with strong antioxidants, and they are very promising as a substitute for chemical preservatives in the food and cosmetic industry.