Vitamin and bioactive compound diversity of seven fruit species from south Brazil.

BACKGROUND: The consumption of native tropical fruits represents an important source of bioactive food and vitamins for consumers. The aim of this study was to determine the composition of vitamins, bioactive compounds and the antioxidant activity of seven native fruits of the Myrtaceae family from south Brazil. RESULTS: Sample 1 of Eugenia pyriformis presented the highest value of ß-carotene (0.1021 g kg-1 ), lutein (0.0511 g kg-1 ), zeaxanthin (0.0370 g kg-1 ), and α-carotene (0.0112 g kg-1 ), of all analyzed samples. The three samples of Eugenia uniflora L presented the highest lycopene (0.1876, 0.1240 and 0.1615 g kg-1 ) and vitamin A content (0.106, 0.035 and 0.178 g kg-1 RAE) of all seven species analyzed. The cyanidin 3-glucoside was the most common anthocyanin found in fruits in the present study. Two samples of Plinia peruviana presented higher antioxidant capacity by the ABTS radical method (0.80 and 0.67 mol TEs kg-1 ) among the fruits analyzed. The samples of Campomanesia xanthocarpa analyzed stood out owing to the high content of vitamin C present (23.89, 36.83 and 35.05 g kg-1 ). The values of pantothenic acid in Plinia peruviana account for 20% of daily requirements. CONCLUSION: In conclusion, the native fruits studied can provide an appreciable amount of vitamins and bioactive compounds. © 2018 Society of Chemical Industry.

Characterization of dietary constituents and antioxidant capacity of Tropaeolum pentaphyllum Lam.

The aim of this study was to evaluate the nutritional content and antioxidant capacity of the tubers, leaves and, flowers of the species Tropaeolum pentaphyllum Lam. The three parts of the plant were analyzed by physicochemical methods, atomic absorption spectrometry, spectrophotometric and chromatographic techniques. The tubers, leaves, and flowers exhibited significant differences in all parameters evaluated. The leaves showed significantly higher values of protein (16.28 ± 0.02 g/100 g), total dietary fiber (27.78 ± 0.15 g/100 g) and quercetin (3798.61 ± 37.57 µg/g) when compared to the tubers and flowers. The study revealed a potential content of the protein, dietary fiber, and flavonoids the species Tropaeolum pentaphyllum, when compared with the sweet potatoes leaves (Ipomoea batatas L.). In addition, the antioxidant activities of leaves and flowers were also higher measured by ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), DPPH (2,2-diphenyl-1-picrylhydrazyl), and TRAP (total radical-trapping antioxidant potential) methods. Tropaeolum pentaphyllum have high nutritional potential that can be exploited to improve nutritional value of various food products.

Bioactive compounds in pindo palm (Butia capitata) juice and in pomace resulting of the extraction process.

BACKGROUND: Pindo palm (Butia capitata, Becc. 1916) is a tropical fruit native to South America and is relatively rich in bioactive compounds. It is often consumed as juice. The aim of this study was, first, to identify the degradation of these compounds by pasteurization and by cold storage (4 °C) of pindo palm juice. Physicochemical properties and concentrations of phenolic compounds, carotenoids and vitamin C have been evaluated on fresh and pasteurized juices. Moreover, another objective was to characterize the nutritional composition and the bioactive compounds of pindo palm pomace, the by-product of juice processing. RESULTS: The results demonstrated a degradation of carotenoids with pasteurization and a degradation of vitamin C with both pasteurization and cold storage of juices. Furthermore, the evaluation of pindo palm pomace showed that it is relatively rich in total phenols (20.06 g gallic acid equivalents kg(-1) dry matter) and in ß-carotene (0.22 g kg(-1) dry matter). CONCLUSION: Thus, from the nutrition viewpoint, it does not seem interesting to pasteurize juice. On the other hand, extraction of carotenoids and phenolic compounds from the pomace appears to be a relevant process.

Development of active biofilms of quinoa (Chenopodium quinoa W.) starch containing gold nanoparticles and evaluation of antimicrobial activity.

Active biofilms of quinoa (Chenopodium quinoa, W.) starch were prepared by incorporating gold nanoparticles stabilised by an ionic silsesquioxane that contains the 1,4-diazoniabicyclo[2.2.2]octane chloride group. The biofilms were characterised and their antimicrobial activity was evaluated against Escherichiacoli and Staphylococcusaureus. The presence of gold nanoparticles produces an improvement in the mechanical, optical and morphological properties, maintaining the thermal and barrier properties unchanged when compared to the standard biofilm. The active biofilms exhibited strong antibacterial activity against food-borne pathogens with inhibition percentages of 99% against E. coli and 98% against S. aureus. These quinoa starch biofilms containing gold nanoparticles are very promising to be used as active food packaging for the maintenance of food safety and extension of the shelf life of packaged foods.

Characterization and antioxidant potential of Brazilian fruits from the Myrtaceae family.

The objective of this study is to evaluating the Brazilian biodiversity through physicochemical characterization and determination of antioxidant potential of three species from the Myrtaceae family, namely yellow guava (Psidium cattleyanum Sabine), guabiroba (Campomanesia xanthocarpa O. Berg), and uvaia ( Eugenia pyriformis Cambess). Guabiroba had the greater quantity of phenolic compounds (9033 mg chlorogenic acid/100 g) and vitamin C (30.58 mg/g) and showed the best TSS/TTA (total soluble solid/total titratable acid) ratio (45.12). For the ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic) method, the guabiroba (507.49 µM Trolox/g) presented the highest antioxidant potential; however, in the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, uvaia (170.26 g/g DPPH) and guabiroba (161.29 g/g DPPH) were not statistically different. The uvaia outranked the other fruits with respect to its high carotenoid (909.33 µg/g) and vitamin A (37.83 µg/g) contents, and the yellow guava, although showing a lower bioactive compound content and antioxidant activity, nevertheless presented much higher values than many traditionally consumed fruits.

The optimization of biohydrogen production by bacteria using residual glycerol from biodiesel synthesis.

In this research the production of hydrogen by Klebsiella pneumoniae BLb01 using residual glycerol discharged from a biodiesel fuel production plant was investigated. Klebsiella pneumoniae BLb01 was isolated from a bacteria-rich sludge of an upflow anaerobic sludge blanket reactor (UASB) of a soybean processing plant. A Plackett-Burman design (P-B) and Response Surface Methodology (RSM) were employed to determine the optimal condition for enhanced hydrogen production. The maximal hydrogen production, which was 45.0 mol % and with 98% of glycerol degradation, was achieved with the optimized medium with the following composition: 30 g L(-1) glycerol; 3 g L(-1) yeast ex tract 3 g L(-1) K(2)HPO(4); 1 g L(-1) KH(2)PO(4); temperature 39°C and pH 9.0. These results show the ability of this new strain of effectively converting residual glycerol into value-added energy products.