Can Storage Stability and Simulated Gastrointestinal Behavior Change the Cytotoxic Effects of Concentrated Guava Leaves Extract against Human Lung Cancer Cells?

The influence of storage stability and simulated gastrointestinal behavior of different extracts of guava leaves extracts (NC: not concentrated, and C10 and C20: concentrated by nanofiltration) was evaluated based on their total phenolic compound (TPC) contents and antioxidant activity as well as on their cytotoxic effects on A549 and Vero cells. The results showed that C10 and C20 presented high stability for 125 days probably due to their high TPC contents and antioxidant activity. The simulated gastrointestinal behavior modified their TPC contents; however, after all digestion steps, the TPC values were higher than 70%, which means that they were still available to exert their bioactivities. Additionally, the cytotoxic effects of these extracts were evaluated before and after the simulated gastrointestinal behavior or under different storage conditions. C10 presented the best selectivity indices (SI) values (IC50 Vero cells/IC50 A549 cells) at both conditions suggesting that it can be considered a potential extract to be developed as a functional food due to its resistance to the gastrointestinal digestion and storage conditions tested.

A review on membrane separation processes focusing on food industry environment-friendly processes.

Food processing industries have led to several environmental impacts due to their high water and energy consumption, as well as soil and water bodies' contamination through improper waste disposal. Membrane Separation Processes (MSP) emerge as an important alternative to enable the adoption of sustainable processes by food industries, since satisfying the requests of innovative processes and equipment design, such as smaller, cleaner, more energy-efficient processes (mild conditions) without the usage of chemical agents. Membrane-based processes fulfill these requirements, and their potential has been broadly recognized in the last few years. This review provides a comprehensive and up-to-date overview of the application of MSP in sustainable processes in the different segments of the food industry over the last 10 years. Waste and wastewater treatment, recovery of valuable compounds and water for reuse, and alternatives to high energy consumption processes were identified as sustainable processes in this context. One trend found is the potential for adding value to production chains by obtaining valuable compounds that have not been explored yet. As a perspective for future research, this review showed that it is advisable to implement MSP in different industrial environments in order to make current processes environmentally sustainable and less polluting.

Functional meat products: Trends in pro-, pre-, syn-, para- and post-biotic use.

In recent years, many studies have been conducted to develop functional meat products, focusing on strategies to maximize health-promoting compounds and reduce the presence of those that may cause negative impacts on the consumer's health. As such, the use of prebiotic, probiotic, and synbiotic agents in meat products has grown considerably. In addition, the use of new generation probiotics in meat products is a novel field that can be explored. With the most recent paraprobiotics/postbiotics update, several components could be tested in meat products. Some interventional studies using meat products added with biotic agents have shown great potential as functional foods by reducing the formation of nitrous compounds in the gut and improving the functionality of the gut microbiota. Although there are few studies focusing on synbiotic meat products, the results are also very promising in this field. As such, this review seeks to describe how probiotics, prebiotics, paraprobiotics and postbiotics can be employed in meat products to give them functional properties, as well as some of the major issues that may arise when using these agents.

Impact of MWCO and Dopamine/Polyethyleneimine Concentrations on Surface Properties and Filtration Performance of Modified Membranes.

The mussel-inspired method has been investigated to modify commercial ultrafiltration membranes to induce antifouling characteristics. Such features are essential to improve the feasibility of using membrane processes in protein recovery from waste streams, wastewater treatment, and reuse. However, some issues still need to be clarified, such as the influence of membrane pore size and the polymer concentration used in modifying the solution. The aim of the present work is to study a one-step deposition of dopamine (DA) and polyethyleneimine (PEI) on ultrafiltration membrane surfaces. The effects of different membrane molecular weight cut-offs (MWCO, 20, 30, and 50 kDa) and DA/PEI concentrations on membrane performance were assessed by surface characterization (FTIR, AFM, zeta potential, contact angle, protein adsorption) and permeation of protein solution. Results indicate that larger MWCO membranes (50 kDa) are most benefited by modification using DA and PEI. Moreover, PEI is primarily responsible for improving membrane performance in protein solution filtration. The membrane modified with 0.5:4.0 mg mL-1 (DA: PEI) presented a better performance in protein solution filtration, with only 15% of permeate flux drop after 2 h of filtration. The modified membrane can thus be potentially applied to the recovery of proteins from waste streams.

Optimization of subcritical water hydrolysis of pecan wastes biomasses in a semi-continuous mode.

Pecan cultivation has increased in recent years. Consequently, the amount of lignocellulosic residuals from its production has expanded. Thus, there is a necessity to explore and add value to their coproducts. The objective of this work was to obtain reducing sugars from pecan biomasses by the optimization of the subcritical water hydrolysis technology in a semi-continuous mode and the physicochemical and morphological characterization of these materials, such as SEM, TGA and FT-IR analysis. Temperatures of 180, 220 and 260 °C, water/solids mass ratio of 15 and 30 g water/g biomass and total reaction time of 15 min were used. The highest reducing sugar yield was 27.1 g/100 g of biomass, obtained at 220 °C and R-15 for pecan shells. TGA, SEM and FT-IR analysis indicated the modifications of structures and compositions of biomasses in fresh and hydrolyzed samples.

Performance of nanofiltration process during concentration of strawberry juice.

The aim of this study was to evaluate the microfiltration and nanofiltration of strawberry juice. Processes performance was evaluated in terms of resistances-in-series, flux decline modeling and extract quality (maintenance of the phenolic compounds). The results obtained showed that concentration polarization is the main resistance to permeate flux in nanofiltration process, representing around 95% of the total resistance. Microfiltration process suffered more influence of the concentration polarization and fouling, next to 47% for both resistances. For all the processes, Hermia's pore blocking models presented good fitting, with R2 over 0.85. The same behavior was observed for a conjugated model which provided a realistic description (R2 > 0.76). Also, nanofiltration process allowed phenolic compounds maintenance, demonstrating the efficiency of this process for strawberry juice concentration.

Enhancement of antioxidant activity and physicochemical properties of yogurt enriched with concentrated strawberry pulp obtained by block freeze concentration.

Strawberry juice was concentrated using block freeze concentration process. The concentrate was used to produce two yogurts with different concentrations of cryoconcentrated strawberry pulp (15% and 30%). Total lactic acid bacteria count, physicochemical and rheological properties was evaluated during storage (7days) for all yogurts. Also, the beverages produced were compared with two commercial trademarks. It was observed that the total lactic acid bacteria count remained higher than 108CFU·mL-1 during the storage time for all beverages studied. The viscosity of the yogurts decreased when the ratio of strawberry cryoconcentrate was increased. The Power Law model was successfully applied to describe the flow of the yogurts, which had a thixotropic behaviour. The incorporation of the cryoconcentrated strawberry pulp in the yogurt resulted in a product with 3-fold more anthocyanins content and antioxidant activity. The enrichment of natural yogurt with strawberry cryoconcentrated pulp proved to be effective in the production of a beverage with higher nutritional characteristics.

Desolventizing of soybean oil/azeotrope mixtures using ceramic membranes.

This work investigates the use of ceramic membranes with different molecular weight cut-offs (MWCOs: 5, 10 and 20 kDa) to desolventize azeotropic solvent mixtures (ethanol/n-hexane and isopropyl alcohol/n-hexane) from soybean oil/azeotrope micelles. Results show that a decrease in the MWCO of a membrane and an increase in the solvent mass ratio in the mixture resulted in a significant reduction in the permeate flux. The 20 kDa membrane presented the highest permeate flux, 80 and 60 kg/m2h for the soybean oil/n-hexane/isopropyl alcohol and soybean oil/n-hexane/ethanol azeotropes, respectively, for an oil to solvent ratio of 1:3 (w/w). The highest oil retention was found using the n-hexane/isopropyl alcohol azeotrope, around 25% in the membrane with the lowest MWCO, that is, 5 kDa. It is shown that the azeotropic mixtures provided intermediate characteristics compared to the original pure solvent behavior.

A solid-state bioprocess for selecting lipase-producing filamentous fungi.

A solid-state bioprocess with wheat bran and rice husk as substrate was used to isolate filamentous fungi with lipase activity from dairy effluent and soil contaminated with diesel oil. The lipase activity was measured in units, with one unit (U) being defined as the amount of enzyme required to liberate 1 micromol of fatty acids per minute per gram of bran substrate (1 U = 1 micromol min(-1) g(-1)). We obtained 24 isolates of filamentous fungi with lipase activity, 17 from the dairy effluent and 7 from the diesel oil-contaminated soil. The best lipase producers were the dairy effluent isolate Aspergillus E-6, with a maximum lipase activity of 49.81 U, and Aspergillus isolate O-4 recovered from the diesel oil-contaminated soil, with a maximum lipase activity of 45.49 U. Both isolates produced their maximum lipase activity eight days after the start of the bioprocess.