RESUMO: São denominadas hortaliças não convencionais as espécies vegetais presentes em determinadas localidades ou regiões, mas que aos poucos foram esquecidas e desvalorizadas. Em virtude das mudanças no comportamento alimentar, o consumo destas hortaliças foi reduzido causando perdas econômicas, sociais e culturais. O resgate deste consumo é de grande importância, visando a preservação da biodiversidade brasileira, os benefícios nutricionais, assim como novas fontes de antioxidantes naturais para a indústria alimentícia. Avaliou-se a composição fitoquímica de espécies vegetais denominadas hortaliças não convencionais: beldroega (Portulaca oleracea), bertalha (Basella rubra), caruru (Amaranthus viridis), peixinho (Stachis lanata) e azedinha (Rumex acetosa), bem como o seu potencial alimentar com base no ranquemento do valor dessas características. Com relação aos minerais avaliados, o caruru apresentou os maiores teores de nitrogênio, cálcio, magnésio, enxofre e ferro. O maior conteúdo de compostos fenólicos foi detectado em peixinho, assim como a menor concentração de taninos condensados (0,14 Eag/g de extrato). Quanto aos carotenoides totais, caruru apresentou a maior concentração, mas o conteúdo de β-caroteno foi maior em peixinho, azedinha tipo I e bertalha. O extrato metanólico de peixinho apresentou forte capacidade de sequestro do radical livre. A maior percentagem de proteína foi detectada na azedinha (tipos I e II). Concluiu-se que os teores de componentes protéicos, minerais e compostos bioativos encontrados nessas hortaliças, caracterizam-nas pelo seu elevado potencial nutricional, podendo o seu consumo regular trazer benefícios à saúde humana.

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Polyhydroxyalcanoates copolymers with 3‐hydroxybutirate (3HB) and 3‐hydroxyvalerate (3HV) co‐monomers, P3(HB‐co‐x%HV), were produced in fed‐batch culture by Ralstonia eutropha DSM428 using fructose as a single carbon source in the first step and adding propionic acid in the second step by alternating feeding. Polymer yield was 0.18 g/L with a content of 24 mol% of the 3HV fraction determined by 1H NMR. NMR measurements indicated that the polymer obtained is isotactic. The copolymer attained 35% of crystallinity according to X‐ray diffraction measurements, and two (020) planes were observed. Thermal behavior presented melting temperature at 154°C and the crystallization temperature was 65°C. A glass transition temperature was observed at −10°C. Average molecular weight measured by GPC was 4.9 × 105 Dalton. Isothermal radial growth rates of spherulites of P3(HB‐co‐24%HV) were studied. All experimental facts and the analysis of the sequence distribution of diads and triads of 3HB and 3HV units led to the conclusion that it is not a completely statistical random copolymer once it contains different types of segments. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers.

Poly(3-hydroxybutyrate) was produced in fed-batch cultures of Ralstonia eutropha DSM 428 and Alcaligenes latus ATCC 29712 on a mineral medium with different carbon sources such as sucrose, sodium lactate, lactic acid, soybean oil and fatty acid. The bacteria converted the different carbon sources supplied into P3HB. The best results were obtained when lactate or soybean oil were supplied as the sole carbon source. The range of number average molar mass (Mn) for the polymers, analyzed by Gel Permeation Chromatography was 1.65 to 0.79 x 10(5) g mol-1. FTIR spectroscopy revealed a characteristic absorbance associated with polyester structures. The crystallinity degree, determinate from X-ray diffractograms, was about 69% in all synthesized polymers. The thermal properties associated to semicrystalline polymers indicated a glass transition at 0.1ºC and a melting point at about 175ºC and enthalpy of 63- 89 J g-1. The ¹H-NMR and 13C-NMR spectra of the polymers were in agreement with the calculated chemical shifts associated with P3HB structures.

The need to increase the product's shelf life and the growing concern to minimize the use of synthetic products encouraged the researchers to evaluate the antioxidant activity and quantify phenolic compounds as chlorogenic acid, caffeic acid, rutin, quercetin and apigenin through the use of HPLC, in 29 accesses of Capsicum baccatum. Capsicum baccatum var. pendulum is one species of the Capsicum genus widely consumed in Brazil. It is the second largest pepper produced in the world. However, its chemical composition and mainly its extract antioxidant activity have been poorly reported in literature. In order to deepen the study of the access properties relating the antioxidant activity versus content of phenolic compounds. It is suggested that the BRS, 1643a, 1611 and 1613, accession could be used as natural antioxidants in the food industry.