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Rice protein isolates (RPI) are promising plant-protein sources but present low solubility and poor surface activity in neutral conditions. Improving these characteristics is a crucial challenge to capitalize on them. This is the first work performing pH-shifting, ultrasound, and heat treatments on a commercial RPI. The combined approaches increased the protein solubility (from ∼2.7% to ∼91.8%) and surface hydrophobicity (up to ∼283%) and induced the formation of less compact and more dispersed protein aggregates. The pH-shifting induced the unfolding of protein molecules and aggregates making them available for modification by both ultrasound and heating, which are supposed to induce further protein unfolding, exposure of buried hydrophobic amino acid, and protein hydrolysis. Also, the combined approaches generated modified RPI able to form oil-in-water emulsions with reduced particle size and enhanced stability than the untreated RPI. Therefore, this work presents an effective combined approach to enhance the techno-functional properties of rice proteins., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Using buffalo whey proteins as carrier agents of sensitive molecules raises an interesting approach allowing adding value and minimizing the pollution impact of this by-product. In this context, this work aims to explore the molecular interactions between buffalo whey proteins concentrate (BWPC) and folic acid (FA). For this purpose, fluorescence, UV and FTIR analysis were performed on aqueous or solid dispersions of a buffalo whey protein concentrate (5 μM) (BWPC), with variable concentrations (0-20 μM) of FA. Fluorescence and absorption data were fitted by Stern-Volmer, Beckett, Förster resonance energy transfer, and sphere-of-action models (R 2  > 0.9). Derived results suggest that BWPC strongly bind to FA through non-covalent interactions and form ground-state complexes. Additionally, BWPC improves the photostability of FA against UV radiation, and chemical denaturation negatively affects the binding properties. Obtained results encourage further studies of BWPC as carrier agents, which could promote innovative applications for this under-utilized proteins source., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The symbiotic community of bacteria and yeast (SCOBY) of Kombucha beverage produces a floating film composed of bacterial cellulose, a distinctive biobased material. In this work, Kombucha fermentation was carried out in six different herbal infusions, where SCOBY was able to synthesise cellulosic films. Infusions of black and green tea, yerba mate, lavender, oregano and fennel added with sucrose (100 g/l) were used as culture media. In all cultures, film production resulted in a maximum after 21 days. Yield conversion, process productivity and antioxidant activity were quantified. Macroscopic and microscopic features of films were determined based on electronic microscopy, calorimetric and mechanical properties and hydration behaviour. Native films from yerba mate had a remarkable antioxidant activity of 93 ± 4% of radical inhibition due to plant polyphenols, which could prevent food oxidation. Results revealed that films retained natural bioactive substances preserving important physicochemical properties, essential for developing active materials., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The objective of this work was to deepen on the study of functional properties of the phytochemicals present in Prosopis alba exudate gum (G), as well as to rule out possible adverse effects of some of its components. Commonly employed purification methods were compared. Filtration prevents further loss of potentially bioactive compounds. The filtrated gum showed a higher concentration of phenolics, flavonoids and tannins than arabic gum, which was correlated with better in vitro antioxidant properties. Particularly, tannins, commonly considered as toxic compounds in exudate gums, were found in lower concentration than in others gums obtained from genus Prosopis and Acacia. The toxicological evaluation performed on rats did not show symptoms of intoxication associated with the administration of the gum. These results provide useful evidence to support the potential use of G as a safe functional food additive with the added benefit of taking advantage of a non-exploited natural resource., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This study was conducted to evaluate the effect of Prosopis alba exudate gum (G) as encapsulating matrix component on water-solid interactions, physical state, oxidative damage and appearance properties of alginate-chitosan encapsulates containing fish oil. With this purpose, water sorption isotherms were obtained at 25 °C. G increased the hygroscopicity of encapsulates, showing a higher monolayer water content (7.87 ± 0.47% db.) than control (1.07 ± 0.04% db.). G introduction reduced the plasticizing effect of water, increasing the a w range (a w  < 0.45) at which samples were in amorphous state and providing the highest protection against lipid oxidation. Appearance properties (chromatic and optical) were affected by hydration and were better maintained in samples containing G at a w  > 0.52. These results allow considering Prosopis alba exudate gum, as a novel excipient to protect fish oil encapsulated in low moisture polyelectrolyte systems, with the added benefits of employing an undervalued natural resource., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In this work, a bottom-up approach based on the study of polyelectrolyte interactions was performed in order to evaluate the effect of Prosopis alba exudate gum as novel excipient for fish oil encapsulation in composed calcium-alginate-chitosan beads. Emulsion and beads properties such as oil distribution, encapsulation efficiency, yield, microstructure and thermo-oxidative protection were evaluated. Alginate and gum exert a synergistic effect on emulsion stability properties, which conducted to better oil distribution in the beads and higher encapsulation efficiencies (98%) and yield (89%). The positive effect of including the gum as wall material was observed in terms of a higher oil retention capacity of the alginate beads, improved oxidative thermal stability and better microstructural features. Present results are promising and allowed considering P. alba gum as a novel non-conventional polyelectrolyte for improving Ca-alginate beads microstructure and stability with the added benefit of taking advantage of an available resource currently untapped., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Derivatized-agarose supports are suitable for enzyme immobilization by different methods, taking advantage of different physical, chemical and biological conditions of the protein and the support. In this study, agarose particles were modified with MANAE, PEI and glyoxyl groups and evaluated to stabilize polygalacturonase from Streptomyces halstedii ATCC 10897. A new immobilized biocatalyst was developed using glyoxyl-agarose as support; it exhibited high performance in degrading polygalacturonic acid and releasing oligogalacturonides. Maximal enzyme activity was detected at 5h of reaction using 0.05g/mL of immobilized biocatalyst, which released 3mg/mL of reducing sugars and allowed the highest product yield conversion and increased stability. These results are very favorable for pectin degradation with reusability up to 18 successive reactions (90h) and application in juice clarification. Plum (4.7°Bx) and grape (10.6°Bx) juices were successfully clarified, increasing reducing sugars content and markedly decreasing turbidity and viscosity., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The aim of the present work was to employ an exudate gum obtained from a South American wild tree (Prosopis alba), as wall material component to enhance the oxidative stability of fish oil encapsulated in alginate-chitosan beads. For this purpose, beads were vacuum-dried and stored under controlled conditions. Oxidation products, fatty acid profiles and lipid health indices were measured during storage. Alginate-chitosan interactions and the effect of gum were manifested in the FT-IR spectra. The inclusion of the gum in the gelation media allowed decreasing the oxidative damage during storage in comparison to the free oil and alginate-chitosan beads. The gum also improved wall material properties, providing higher oil retention during the drying step and subsequent storage. Fatty acids quality and lipid health indices were widely preserved in beads containing the gum. Present results showed a positive influence of the gum on oil encapsulation and stability, being the main mechanism attributed to a physical barrier effect., (Copyright © 2015 Elsevier Ltd. All rights reserved.)