Alginate Particles for Encapsulation of Phenolic Extract from Spirulina sp. LEB-18: Physicochemical Characterization and Assessment of In Vitro Gastrointestinal Behavior.

Encapsulation can be used as a strategy to protect and control the release of bioactive extracts. In this work, an extract from Spirulina sp. LEB-18, rich in phenolic compounds, was encapsulated in biopolymeric particles (i.e., composed of alginate) and characterized concerning their thermal behavior using differential scanning calorimetry (DSC), size, morphology, swelling index (S), and encapsulation efficiency (EE%); the release profile of the phenolic compounds at different pHs and the particle behavior under in vitro gastrointestinal digestion were also evaluated. It was shown that it is possible to encapsulate the phenolic extract from Spirulina sp. LEB-18 in alginate particles with high encapsulation efficiency (88.97%). It was also observed that the particles are amorphous and that the encapsulated phenolic compounds were released at a pH 7.2 but not at pH 1.5, which means that the alginate particles are able to protect the phenolic compounds from the harsh stomach conditions but lose their integrity under intestinal pH conditions. Regarding bioaccessibility, it was observed that the encapsulated phenolic compounds showed higher bioaccessibility compared to phenolic compounds in free form. This work increases the knowledge about the behavior of alginate particles encapsulating phenolic compounds during in vitro gastrointestinal digestion. It also provides essential information for designing biopolymeric particle formulations encapsulating phenolic compounds for application in pharmaceutical and food products.

Vinegar from Anacardium othonianum Rizzini using submerged fermentation.

BACKGROUND: Anacardium othonianum Rizzini is a native Cerrado fruit, recently described in the literature. Its use is restricted to its native region and there is a lack of studies regarding production of vinegar from the pulp. This work aims to investigate the production of A. othonianum Rizzini vinegar using submerged fermentation. RESULTS: The density, alcohol content, proximal composition, pH, color coordinates, and chromatographic profile of the volatile compounds were analyzed in the slurry, fermented juice, and vinegar produced from the corpulent parts of A. othonianum Rizz. Sensory acceptance and willingness to pay were also assessed with vinegar at 4% and 6% of total acidity. The results indicated compliance with European legislation and the presence of volatile compounds such as carbon dioxide, acetic acid, ethanol, and acetaldehyde in the analyzed vinegars. Our results indicate the potential of vinegar production from A. othonianum, with 74% and 86% willingness to pay. CONCLUSIONS: The process of transformation of the fruit pulp into new products can contribute to fruit valorization and consequent preservation of the plant in the Cerrado biome. To the best of our knowledge, this is the first report of volatile compounds and minerals in A. othonianum Rizz. slurry. Our observations can be used as a basis for future studies regarding the preparation of vinegars from this species and for investigating their application in cooking and guiding consumer perception. © 2020 Society of Chemical Industry.

Liposomes loaded with phenolic extracts of Spirulina LEB-18: Physicochemical characterization and behavior under simulated gastrointestinal conditions.

Liposomes composed of rice (RL) and soybean (SL) lecithins were produced by reverse phase evaporation and used for the encapsulation of phenolic extracts from Spirulina LEB-18 (S-RL and S-SL for liposomes of rice and soybean lechitin, respectively). Liposomes were characterized in terms of size distribution, polydispersity index, and ζ-potential; the chemical interactions between the phenolic compounds from Spirulina and liposomes were evaluated by Fourier Transform Infrared Spectroscopy (FTIR), and X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were used to evaluate their crystallinity pattern. The release behavior of phenolic extracts was evaluated under two different pH conditions. Afterwards, in vitro digestibility of liposomes was evaluated in a dynamic gastrointestinal system. Liposomes exhibited high encapsulation efficiency (88.28% and 97.35% for S-RL and S-SL, respectively) and sizes ranging between 250 and 291 nm, showing to be good candidates for the encapsulation of phenolic extracts obtained from microalgae. Results showed that liposomes are stable at low pH values and that they are able to resist to the stomach conditions but they lose their integrity under intestinal conditions. This work increases the knowledge about the effects of in vitro gastrointestinal digestion on liposomes and provides important information for the design of liposome formulations aiming their application in pharmaceutical and food applications.