Influence of cultivar and of conventional and organic agricultural practices on phenolic and sensory profile of blackberries (Rubus fruticosus).

BACKGROUND: Consumer demand for organic products is increasing because of their claimed health benefits. Blackberries are a rich source of polyphenols, with high antioxidant activity; nevertheless, the impact of organic versus conventional agricultural practices on its phytochemical composition is unknown. 'Loch Ness' and 'Chester Thornless' were selected as blackberry cultivars for this study because of their desired sensory and technological properties, which make them more suitable for export. RESULTS: 'Loch Ness' variety presented a higher amounts of polyphenols and higher antioxidant activity when compared to the 'Chester Thornless' variety. The impact of agricultural practices on the phytochemical composition of the two varieties was contradictory. Under organic agricultural practices, levels of polyphenols increased for 'Loch Ness' and decreased for 'Chester Thornless', whereas the soluble solids content increased in both varieties. These changes in composition were correlated with changes observed in the blackberries' sensory profile. CONCLUSION: The effect of agricultural practices on the blackberries' chemical and sensory profile was dependent on the variety and cannot be generalized. © 2018 Society of Chemical Industry.

A comparative study on composition and antioxidant activities of supercritical carbon dioxide, hexane and ethanol extracts from blackberry (Rubus fruticosus) growing in Poland.

BACKGROUND: Large quantities of blackberry seeds are produced as a pomace during the processing of juice and jam production; this by-product is a very interesting raw material both for oil manufacturing and as a source of bioactive compounds. In this work the composition, yield and antioxidant activity of three types of Rubus fructicosus pomace extracts isolated by liquid extraction using solvents of different polarity, as well with supercritical CO2 fluid extraction have been compared. RESULTS: The highest extract yield was reported for Soxhlet extraction using ethanol as a solvent (14.2%). Supercritical carbon dioxide and hexane extracts were characterised by the highest content of phytosterols (1445 and 1583 mg 100 g-1 of extract, respectively) among which ß-sitosterol was the main one, while the concentration of tocopherols, with predominant γ-isomer, was the highest for both hexane and ethanol extracts, being 2364 and 2334 mg 100 g-1 , respectively. Using a GC-MS method 95 volatiles, in which non-saturated aldehydes were predominant, were identified in the essential oil of seed pomace and in the volatile oil isolated from supercritical extract. The ethanolic extract which is characterised by the highest phenolic content (9443 mg GAE 100 g-1 ) exhibited the highest antioxidant activity (according to the ABTS•+ and DPPH• assays). CONCLUSION: All pomace extracts examined were of high quality, rich in essential omega fatty acids and with a very high content of bioactive compounds, such as phytosterols and tocopherols. The high nutritional value of extracts from berry seed pomace could justify the commercialisation of specific extracts not only as food additives but also as cosmetic components. © 2017 Society of Chemical Industry.

Bioactive comparison of main components from unripe fruits of Rubus chingii Hu and identification of the effective component.

Dried and unripe fruit of Rubus chingii Hu, known as "Fu-pen-zi" in Chinese, has been used as a food and tonic in China for a long time. In order to analyze its effective ingredients, polysaccharides, flavonoids, saponins and alkaloids were extracted from the unripe fruits and their contents were determined. The in vitro antioxidant, anticomplementary and anticancer activities against human lung adenocarcinoma A549 cells of the four major constituents were investigated. Results showed that total flavonoids exhibited an obvious antioxidant activity, which was very close to ascorbic acid. The anticomplementary and anticancer activities of flavonoids were also the best among the four chemical compositions. Therefore, extraction process optimization of flavonoids was conducted using response surface methodology. The optimal conditions were as follows: extraction temperature 72.8 °C, ethanol concentration 30.67%, extraction time 2.66 h, and a liquid/solid ratio of 19.54 : 1. In addition, total flavonoids were subsequently separated by column chromatography and the major flavonoid was identified as tiliroside. Further experimental data revealed that tiliroside treatment could suppress the proliferation and induced the apoptosis of A549 cells.

Effect of cultural system and essential oil treatment on antioxidant capacity in raspberries.

The effects of cultural system and essential oil treatment on antioxidant capacities in raspberries were evaluated. Raspberries were hand-harvested from organic and conventional farms in Maryland, USA, and were treated with essential oil including carvacrol, anethole, cinnamic acid, perillaldehyde, cinnamaldehyde, and linalool. Results from this study showed that raspberries grown from organic culture exhibited higher value of antioxidant capacities and individual flavonoids contents. Moreover, the organic culture also enhanced the activities of antioxidant enzymes. In addition, essential oil treatments promoted the antioxidant enzymes activities and antioxidant capacities of raspberries, and the most effective compound was perillaldehyde. In conclusion, raspberries produced from organic culture contained significantly higher antioxidant capacities than those produce from conventional culture. Postharvest essential oil treatments have positive effect on enhancing antioxidant capacities in raspberries from both organic and conventional cultures.