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BACKGROUND: Blackberries have a high content of bioactive compounds such as anthocyanins and ellagitannins, which are associated with health benefits against cardiovascular diseases, cancer, diabetes, and other inflammatory conditions. OBJECTIVE: This study evaluated the effect of a tropical highland blackberry (Rubus adenotrichos Schltdl.) beverage (50% v/v) on lipids, glucose and antioxidant parameters of healthy individuals. METHODS: Thirteen healthy individuals of both sexes were assigned into two groups in a randomized crossover design. Each participant was subjected to a high fat and high carbohydrate diet challenge and drank 250 mL of either blackberry beverage or water with every meal, three times a day for 14 days. Total cholesterol, triglycerides, LDL cholesterol, HDL cholesterol, glucose level, superoxide dismutase (SOD), and catalase (CAT) enzymatic activities were assessed from plasma. RESULTS: Plasma levels of triglycerides, total cholesterol, and glucose levels significantly decreased (p < 0.05) after consuming the blackberry beverage. Changes in LDL and HDL cholesterol levels were not statistically significant (p > 0.05). CAT and SOD enzymatic activities increased slightly, although not statistically significant (p > 0.05). CONCLUSION: Drinking a beverage from a blackberry micro-filtered juice improved plasma lipid and glucose profiles, as well as CATand SOD enzymatic activities in healthy participants. [ABSTRACT FROM AUTHOR]

Summary: Slices (1.5 mm thick) of green papaya were impregnated through osmotic dehydration with a blackberry juice–sucrose solution to produce an intermediate moisture product. The effect of processing temperature (T) and sucrose‐added molality (msucrose) on mass transfer during the operation was assessed, using a response surface methodology (RSM). The RSM was used to model water loss, sugar and anthocyanin gain during the process. Increasing sucrose molality resulted in increasing water loss and sugar gain, but decreasing anthocyanin gain. Water transfer therefore limits anthocyanin impregnation, but not sucrose incorporation. Afterwards, the impact of heat treatment at high temperatures was analysed, using numerical simulation. The conditions of the combined process, designed to achieve an anthocyanin‐rich final product, are low sucrose‐added molalities (sucrose molality < 1 mol kg–1) and high processing temperatures (T > 50 ºC) for osmotic dehydration, coupled with high‐temperature, short‐time (HTST) heat treatments for product stabilisation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Blackberry fruits have recently gained attention because of their considerable amounts of polyphenols. OBJETIVE: The aim of this study is to compare the physicochemical composition and contents of the main polyphenolic compounds of nine tropical highland blackberry genotypes grown in Costa Rica, and to evaluate the effect of environmental conditions and farming practices on physicochemical composition of fruits of 'Wine red thorn', which is the most widely grown blackberry genotype in Costa Rica. METHODS: Nine blackberry genotypes were harvested at fully ripe stage. Environmental conditions (geographic location and harvest season) and farming practices (organic and conventional techniques) were evaluated to determine their effects on physicochemical composition and polyphenolic compounds of 'Wine red thorn' blackberries. Anthocyanins and ellagitannins contents were determined by HPLC-DAD. RESULTS: The tropical highland blackberries contained appreciable levels of polyphenols. Anthocyanin content ranged from 2.9±0.1 to 12±1 g cyanidin-3-glucoside equivalents/kg dry weight (DW); ellagitannin content ranged from 9.3±0.8 to 47±3 g ellagic acid equivalents/kg DW. The influence of environmental conditions and farming practices on physicochemical characteristics of 'Wine red thorn' blackberries was significant (p < 0.05). Blackberries harvested during the dry season had higher contents of sugars and anthocyanins than blackberries harvested during the rainy season. Organic blackberries had higher levels of ellagitannins than conventionally grown fruits. CONCLUSIONS: These data prove that Costa Rican blackberries are a good source of polyphenolic compounds, especially ellagitannins. Environmental and farming conditions can be exploited to obtain high quality blackberry fruits. [ABSTRACT FROM AUTHOR]

The health benefits attributed to berries are largely dependent on their bioavailability. This study evaluated the antioxidant activity for different samples of blackberry juice submitted to an in vitro digestion. The HPLC analysis demonstrated that gastric conditions had only a slight impact on the phenolic composition, but the digestion simulating intestine conditions caused marked changes. The dialyzed fraction, which represents the serum available material, showed 33% and 35% less activity against nitrogen-derived radicals and a significant reduction of 46% in the inhibitory capacity against intracellular ROS. Other models used to evaluate the capacity to inhibit lipid peroxidation did not show significant differences in any of the digestion samples. Our results suggest that blackberry polyphenols could exert their antioxidant capacity after passage through the GIT. However, the dialyzed fraction suffers a partial depletion of its antioxidant ability, this could be attributed to the absence of ellagitannins. [ABSTRACT FROM AUTHOR]

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This study evaluated the effects of mechanical and enzymatic pretreatments on the extraction of anthocyanins and ellagitannins from blackberries. Continuous pressing yielded significantly higher turbidity values and content of anthocyanins and ellagitannins ( P < 0.05) compared with discontinuous pressing. The use of enzymatic pretreatment also significantly increased the extraction of polyphenolic compounds ( P < 0.05), in particular that of total ellagitannins, on average from 437 to 982 mg ellagic acid equivalents/100 g (dry basis) when using discontinuous pressing. When microfiltration was used, the content of ellagitannins and anthocyanins was found to be similar in both feed and permeate when discontinuous press was used to extract the juice, but a significant decrease of 34% (dry basis) was found in the concentration of ellagitannins when continuous pressing was used ( P < 0.05). These results should be useful for future efforts to increase the extraction of polyphenolic compounds from fruits and vegetables. Practical Applications Blackberries have high contents of potentially bioactive polyphenolic compounds, mainly anthocyanins and ellagitannins. Therefore, processes must be optimized not only to obtain large amounts of juice from this fruit, but also to efficiently extract the compounds of interest. The methodology and results presented in this study should be beneficial for processors that aim to increase the recovery of potentially bioactive polyphenolic compounds from fruit using mechanical and enzymatic pretreatments. Furthermore, this study evaluated the potential of cross-flow microfiltration as a viable operation for cold stabilization of blackberry juice, while obtaining acceptable permeate flux and membrane retention of the compounds of interest. It is envisioned that this technology could be used in the same manner to ensure the microbiological stability of polyphenolic-enriched fruit juices and extracts. [ABSTRACT FROM AUTHOR]

Solar ultraviolet ( UV) radiation, particularly its UVB (280-320 nm) spectrum, is the primary environmental stimulus leading to skin carcinogenesis. Several botanical species with antioxidant properties have shown photochemopreventive effects against UVB damage. Costa Rica's tropical highland blackberry ( Rubus adenotrichos) contains important levels of phenolic compounds, mainly ellagitannins and anthocyanins, with strong antioxidant properties. In this study, we examined the photochemopreventive effect of R. adenotrichos blackberry juice ( BBJ) on UVB-mediated responses in human epidermal keratinocytes and in a three-dimensional (3D) reconstituted normal human skin equivalent ( SE). Pretreatment (2 h) and posttreatment (24 h) of normal human epidermal keratinocytes ( NHEKs) with BBJ reduced UVB (25 mJ cm−2)-mediated (1) cyclobutane pyrimidine dimers (CPDs) and (2) 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) formation. Furthermore, treatment of NHEKs with BBJ increased UVB-mediated (1) poly(ADP-ribose) polymerase cleavage and (2) activation of caspases 3, 8 and 9. Thus, BBJ seems to alleviate UVB-induced effects by reducing DNA damage and increasing apoptosis of damaged cells. To establish the in vivo significance of these findings to human skin, immunohistochemistry studies were performed in a 3D SE model, where BBJ was also found to decrease CPDs formation. These data suggest that BBJ may be developed as an agent to ameliorate UV-induced skin damage. [ABSTRACT FROM AUTHOR]

Abstract: Tropical highland blackberry (Rubus adenotrichus Schltdl.) is a good source of antioxidants and contains appreciable levels of phenolic compounds, mainly ellagitannins and anthocyanins. This study examined the influence of three ripening stages on phenolic contents. Major anthocyanin pigments increased from 0.20 (red fruit) to 1.34mgg−1 fresh weight (FW) (fully ripe fruit), whereas ellagitannins and ellagic acid derivatives dropped from 3.8 to 2.2mg ellagic acid equivalents g−1 (FW). Flavonols also dropped from 5.1 to 2.0mg quercetin equivalents 100g−1 (FW). Consequently, values for total phenolic compounds ranged from 5.8 to 5.2mg gallic acid equivalents g−1 (FW), showing no specific trend. Antioxidant activity (H-ORAC) increased from 38.29 to 64.00μmol of Trolox equivalents g−1 (FW) during ripening. When compared with other commercial cultivars, R. adenotrichus stands out for high H-ORAC value, although comparatively it possesses low anthocyanin content and average total phenolic content. [Copyright &y& Elsevier]

Berries are commonly consumed as juice, and juice-processing conditions could affect their bioactive compounds. This study evaluated the effect of thermal treatments on the antioxidant capacity of blackberry juice polyphenols. Pasteurized blackberry juices were prepared at 75 °C for 15 s (JP75) and 92 °C for 10 s (JP92). Polyphenol analysis showed that for JP75 and JP92, anthocyanin concentrations decreased significantly, compared to non-pasteurized juice (NPJ), whereas ellagitannins were not significantly affected. The evaluation of the DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging capacity showed a significant decrease of 26% for JP75 and 27% for JP92, and, for the NO (nitric oxygen) scavenging capacity, the activity was reduced 15% for JP75 and 16% for JP92. There were no significant reductions observed for the peroxidation inhibitory capacity of the pasteurized juices for any of the oxidation substrates tested: liposomes, liver homogenates and erythrocytes. Furthermore, the intracellular antioxidant capacity showed no significant differences due to thermal treatments. The concentration of phenols necessary to scavenge 50% of the radical oxygen species was 204 ± 9 μg/mL for NPJ, 219 ± 10 μg/mL for JP75 and 220 ± 9 μg/mL for JP92. This study revealed that pasteurized blackberry juices maintained their biological properties related to inhibition of peroxidation and their capacity to scavenge intracellular radicals. [ABSTRACT FROM AUTHOR]