IntroductionThere is an increasing interest in phytochemicals as new sources of natural antioxidant and antimicrobial agents. The use of synthetic antioxidants in the food industry is severely restricted as to both application and level (TAWAHA et al., 2007;PENG et al., 2005). Currently, there is a strong debate about the safety aspects of chemical preservatives, since they are considered responsible for many carcinogenic and teratogenic attributes, as well as residual toxicity (MOREIRA et al., 2005).Plant-derived polyphenols receive considerable attention because of their potential antioxidant and antimicrobial properties (MOREIRA et al., 2005;PROESTOS;SERELI;KOMAITIS, 2006). Phenolic compounds exhibit a considerable free-radical scavenging (antioxidant) activity, which is determined by their reactivity as hydrogen-or electron-donating agents, the stability of the resulting antioxidant-derived radical, their reactivity with other antioxidants and, finally, their metal chelating properties (RICE-EVANS; MILLER; PAGANGA, 1997).Rosemary (Rosmarinus officinalis L.) is a spice and medicinal herb widely used around the world. Of the natural antioxidants, rosemary has been widely accepted as one of the spices with the highest antioxidant activity (PENG et al., 2005). Rosemary essential oil is also used as an antibacterial, antifungal (OLUWATUYI; KAATZ;GIBBONS, 2004;FERNÁNDEZ-LÓPEZ et al., 2005;KABOUCHE et al., 2005;REZZOUG;BOUTEKEDJIRET;ALLAF, 2005) and anticancer agent (LEAL et al., 2003). Ouattara et al. (1997) investigated the antibacterial activity of selected essential oils against some food spoilage organisms. They concluded that the essential oils of cinnamon, clove and rosemary were the most active. Similar results were obtained by Valero and Salmeron (2003) for the antibacterial activity of rosemary essential oil against Bacillus cereus strains grown in carrot broth.Many compounds have been isolated from rosemary, including flavones, diterpenes, steroids, and triterpenes. Of these, ResumoExtratos das partes aéreas de alecrim foram obtidos utilizando fluidos supercríticos (FSC) e extrações Sohxlet. Sua composição foi analisada com GC-MS. Os extratos foram analisados com base nos compostos repostados na literatura como tendo atividade antimicrobiana e antioxidante. Os extratos de alecrim foram testados quanto à atividade antioxidante (radicais DPPH e conteúdo total de fenólicos -reagente

Due to its coloration, the fig (Ficus carica L.) peel, a by-product of fruit processing and/or consumption, is a potential source of anthocyanin compounds. In the present study different extraction techniques (heat, ultrasound, and microwave) were compared aiming to recover the anthocyanin pigments and optimize its extraction conditions. A response surface methodology tool with three factors and five levels for each factor was used according to a circumscribed central composite design. The variables tested for the heat and microwave extraction methods were time, temperature, and solvent proportion (ethanol/water ratio), meanwhile, for the ultrasound method, the variables tested were the ultrasonic power, time, and solvent proportion. The anthocyanin composition of the extract was determined by HPLC-DAD-ESI/MS, and the used criteria responses were: i) quantification of cyanidin 3-rutinoside (C) in the extracted residue (mg C/g R) and in the dried peel (mg C/g P dw), and the extraction yield of the obtained residue (g R/g P dw). Ultrasound extraction was the most effective method, yielding 3.82 mg C/g R at the optimal global extraction conditions (21 min, 310 W, and 100% of ethanol). Additionally, the solid-to-liquid ratio effect was studied at the optimal conditions, using a dose-response format, in view of its plausible transference to industrial level. For the ultrasound method, an increased non-linear relationship was observed for concentrations in the range 5 to 200 g/L, being the optimal solution close to 150 g/L. In brief, the obtained results show the potential of fig peels as a source of anthocyanin pigments, with potential uses in various industrial fields, such as food, pharmaceutical, and cosmetic.

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The present work describes the evaluation of fig peels and blackthorn fruit extracts as natural purple colorants in doughnuts (icing) and in a typical Brazilian pastry called "beijinho". The extracts were screened for their antioxidant activity as well as their antibacterial capacity. Nutritionally, the employed extracts did not induce significant changes, contrarily to the observed for the rheological features, mainly the darker purple tone observed when blackthorn extract was used in the icing solution. After 24 h, both prepared formulations showed a decrease in color intensity, with no significant differences between fig and blackthorn extracts. In turn, the firmness and consistency of the doughnuts benefited from using natural colorants in the icing solution, while "beijinhos" became softer and chewier, which are valued attributes. A significant increase in the antioxidant and antimicrobial activities was also observed for both natural extracts. Accordingly, the evaluated extracts are promising candidates as natural food colorants.