Antioxidant and emulsifying properties of a galactose-rich heteropolysaccharide from Plinia cauliflora peels.

In this study functional properties of a galactose-rich heteropolysaccharide (GH) were accessed. The bands of a galactose-rich polysaccharide were found in FTIR spectra, including those from the fingerprint region. GH was characterized as a dark-red material (L* 25.86 ± 0.75, a* 9.46 ± 1.01, b* 0.65 ± 0.14, Chroma 9.48 ± 1.02) with antioxidant activity of 21.5 ± 0.08, 12.1 ± 0.06 and 0.46 ± 0.04 mmol Trolox Eq/mg GH in FRAP, DPPH and ABTS, respectively. GH presented 44.9% of esterification degree and 10.73 ± 0. 01 mg of GAE/g. The production parameters of GH emulsions (GH concentration, time and ultrasound power) were optimized using a 23 Central Composite Rotatable Design (CCRD). Emulsion droplets presented particle size (d µm) varying from 0.823 ± 0.065 to 1.926 ± 0.151, polydispersity index (PDI) from 0.10 ± 0.05 to 0.40 ± 0.01 and zeta potential from -29.25 ± 3.98 to -33.75 ± 1.77. Finally, the high emulsifying activity (EA) (96.67%) and emulsion stability (ES) (97.44%) allow suggesting that GH is a promising polysaccharide for food applications.

Production of anti-inflammatory films based on cashew gum polysaccharide and polyvinyl alcohol for wound dressing applications.

In the present study, we aimed to produce CGP/PVA films containing entrapped anti-inflammatory drugs for wound dressing applications. Using a 33-1 fractional factorial design, the effect of each component was evaluated on the physicochemical and morphological properties of the produced materials. The best formulation for entrapment of diclofenac sodium and ketoprofen was also determined. The produced films presented high swelling capacity, with some formulations showing o porous structure. CGP/PVA films showed a maximum retention of 75.6% for diclofenac sodium and 32.2% for ketoprofen, and both drugs were released in a controlled manner for up to 7 h. The drug release kinetic was studied, and the data were fitted using a Korsmeyer-Peppas model, which suggested that the release mechanism is controlled by diffusion. These results indicate that CGP/PVA-based matrices have great potential to be used as drug-delivery systems for wound dressing applications, contributing to prolonging the drug's action time and then improving their anti-inflammatory efficacy.

Development of a Halochromic, Antimicrobial, and Antioxidant Starch-Based Film Containing Phenolic Extract from Jaboticaba Peel.

In this study, the antioxidant, antimicrobial, mechanical, optical, and barrier attributes of Solanum lycocarpum starch bio-based edible films incorporated with a phenolic extract from jaboticaba peel were investigated. Aiming to determine the effect of the polymers and the phenolic extract on the properties of the films, a three-factor simplex-lattice design was employed, and the formulation optimization was based on the produced films' antioxidant potential. The optimized formulation of the starch-PEJP film showed a reddish-pink color with no cracks or bubbles and 91% antioxidant activity against DPPH radical. The optimized starch-PEJP film showed good transparency properties and a potent UV-blocking action, presenting color variation as a function of the pH values. The optimized film was also considerably resistant and highly flexible, showing a water vapor permeability of 3.28 × 10-6 g m-1 h-1 Pa-1. The microbial permeation test and antimicrobial evaluation demonstrated that the optimized starch-PEJP film avoided microbial contamination and was potent in reducing the growth of Escherichia coli, Staphylococcus aureus, and Salmonella spp. In summary, the active starch-PEJP film showed great potential as an environmentally friendly and halochromic material, presenting antioxidant and antimicrobial properties and high UV-protecting activity.

Effect of extrusion and autoclaving on the biological potential of proteins and naturally-occurring peptides from common beans: Antioxidant and vasorelaxant properties.

Aiming to understand the impact of hardening on the biological potential of bean protein and peptides, we evaluated the antioxidant and vasorelaxant properties of common beans after and before hardening. It was also evaluated the effect of extrusion and autoclaving in the biological potential of hardened beans. In general, hardening caused a reduction from 13.5 to 39.6% on the antioxidant activity of the peptide-rich fractions. On the other hand, hardening did not strongly interfere with the vascular reactivity in thoracic aorta rings, being observed maximal relation varying from 801% to 84.7%. The thermal treatment caused a general increase in the antioxidant and vasorelaxant potential of these fractions, being observed EC50 values ranging from 0.22 mg mL-1 to 0.26 mg mL-1. We can conclude that hardening did not seem to affect definitively the bioactivity of the obtained peptide-rich fractions. Finally, this study allows suggesting practical applications of extrusion as a thermal process in the production of functional food ingredients, and as ready-to-eat products presenting nutraceutical potential. In addition, autoclaving can be used as a pre-treatment of the hardened grains aiming to use them as whole grains with potentialized benefits for human health.

Morphological and physicochemical characterization of starches from underground stems of Trimezia juncifolia collected in different phenological stages.

In this study, starches from underground stems of Trimezia juncifolia were evaluated during dry season (DSS), wet season (WSS) and sprouting (SS). Results evidenced that drought stress did not interfere with the yield, amylose content and degree of polymerization (DP) of amylopectin. However, the extraction yield in SS was 58% lower, being observed and increase of 7.5% in the content of amylose, and 13.5% in DP values for SS amylopectin, with a predominance of A-chains. The amount of total sugar, the starch granules size as well as solubility and swelling properties varied as function of the phenological status. Also, starch granules changed from A-type polymorph in DSS and SS to a CA-type in WSS. Nevertheless, it was observed a crystallinity reduction from 56% in DSS to 37.1% in SS. In addition, thermograms evidenced the presence of amylose-lipid complexes, with endothermic transition temperatures being affected by drought stress and sprouting. Finally, results demonstrate that underground stems from T. juncifolia have adaptative strategies involving changes in the morphological and physicochemical properties of the starch granules.

A galactose-rich heteropolysaccharide extracted from "jaboticaba" (Plinia cauliflora) peels.

The objective of this work was to extract, identify and characterize a galactose-rich heteropolysaccharide (GH) from "jaboticaba" peel. The best conditions to extract the GH according to a 23 full-factorial experimental design were 90 °C/30 min/pH 1.0, resulting in a 32.32 % yield using lyophilized sample. The chemical structure analyzed by GC/MS and NMR spectra (HSQC/HSQC-TOCSY) showed that the main chain of GH consists of a (1→4) galactoside branched at carbon 3, containing galactose (67.21 %), glucose (15.78 %), arabinose (9.78 %), rhamnose (2.26 %) and traces of esterified and non-esterified uronic acids. Rheological studies revealed that GH suspensions behave as a Newtonian fluid, with calculated molecular mass of 1.48 × 105 Da. The absolute viscosity of 1 % (w/v) aqueous suspension of GH decreased from 25 mPa s to 10 mPa s in NaCl and 7 mPa s in CaCl2, indicating the polyelectrolyte character of GH.

Antihyperglycemic and hypoglycemic activity of naturally occurring peptides and protein hydrolysates from easy-to-cook and hard-to-cook beans (Phaseolus vulgaris L.).

The present study was undertaken to examine the antidiabetic potential of naturally occurring peptides and hydrolysate fractions from easy-to-cook (ETC) and hard-to-cook (HTC) beans. All fractions were tested regarding their in vitro inhibitory activities against α-amylase and α-glucosidase as well as in vivo anti-hyperglycemic and hypoglycemic effects. Results evidenced that the peptide fractions with the lowest molecular weight (<3 kDa) have the highest inhibitory activities, and a 16.9%-89.1% inhibition of α-amylase and 34.4%-89.2% inhibition of α-glucosidase were observed. Regarding the antihyperglycemic activity, the fraction ETCNO3-10 showed a better performance than the positive control (acarbose). In addition, results from hypoglycemic activity evidenced that the tested peptide fractions were able to decrease the glucose levels at the same extension of glibenclamide, maintaining a constant basal glucose level without a postprandial hyperglycemia peak. Finally, it is possible to suggest that the naturally occurring peptides and hydrolysate fractions obtained from ETC and HTC common beans could be used in functional food production or pharmaceutical formulations to prevent diabetes.

Use of Statistical Design Strategies to Produce Biodegradable and Eco-Friendly Films from Cashew Gum Polysaccharide and Polyvinyl Alcohol.

This work reports the production and characterization of biodegradable and eco-friendly films based on cashew gum polysaccharide (CGP) and polyvinyl alcohol (PVA), using the statistical design strategy. Results show that CGP/PVA films are pH stimuli-responsive, allowing their use in a magnitude of biotechnological applications. The morphological and dimensional characterization evidences a positive influence of polymers in the dimensional properties. In addition, the microstructural analysis shows that films have different morphologies depending on the content of polymers and oxidant agent. On the other hand, the thickness and light transmission values are positively influenced by CGP and PVA and negatively influenced by NaIO4. Results from mechanical properties show that the traction force is positively influenced by NaIO4, while the elongation is only affected by the PVA concentration. In summary, considering the morphological, optical and mechanical properties of the CGP/PVA films it is possible to suggest their utilization in different fields as promising packaging materials or matrices for immobilization and/or encapsulation of biomolecules.

Effect of drought stress on the morphological and physicochemical properties of starches from Trimezia juncifolia.

In this study corms from Trimezia juncifolia were collected in the wet (WSS) and dry (DSS) seasons and used for extraction of starch. Results evidenced that drought stress interfered with the yield, morphological and physicochemical properties of the starches. In addition, it was observed a higher content of amylose for DSS (44%) when compared with WSS (41%). Drought stress did not interfere with the degree of polymerization (DP) of amylopectin, whereas decreased the amylose DP for DSS. Also, starch granules changed from A-type polymorph in the DSS to a CC-type in WSS. Drought stress reduced the starch crystallinity from 27% in WSS to 25.9% in DSS. In addition, the endothermic transition temperatures and enthalpy change of transition were also affected by drought stress. Finally, results clearly demonstrate that changes in the morphological and physicochemical properties of the starch granules figure as adaptive strategies of T. junciolia to drought stress.

Immobilization of antimicrobial trypsin inhibitors onto cashew gum polysaccharide/PVA films.

In this work, films produced by blending cashew gum polysaccharide (CGP) with PVA were used as support for immobilization of trypsin inhibitors with antimicrobial activity obtained from Platypodium elegans (PeTI) and Inga laurina (ILTI). The produced films had a homogeneous macroscopic surface with an absence of bubbles and cracks. SEM of CGP/PVA confirmed the porous structure of these materials, being observed a high incidence of pores with a diameter ranging from 0.4 to 7 µm after swelling in a solution with basic pH. CGP/PVA-F2 presented improved mechanical properties when compared with CGP/PVA-F1, showing higher values of tensile strength and elongation. Results from immobilization efficiency proved that both CGP/PVA formulations were able to entrap trypsin inhibitors. However, the inhibitory activity of the immobilized PeTI was two-fold higher than that observed for ILTI, independently of the film formulation. The release profile of PeTI was similar in both formulations, with an increase in the amount of released inhibitor as a function of time. For ILTI, the CGP/PVA-F2 presented higher release than that from CGP/PVA-F1, achieving a maximum release after 720 min. Also, the released inhibitors showed high stability after 24 h of storage. This study confirmed that CGP/PVA films are versatile and efficient materials to be used as support for immobilization of biomolecules.

A stimuli-responsive and bioactive film based on blended polyvinyl alcohol and cashew gum polysaccharide.

In this study, a stimuli-responsive, biodegradable and bioactive film was produced by blending cashew gum polysaccharide (CGP) and polyvinyl alcohol (PVA). The film presented malleability and mechanical properties enabling an easy handling. Wetting the film changed the optical property from opacity to levels of transparency higher than 70% and resulted in up to 2-fold increase in its superficial area. Different swelling indexes were obtained varying the pH of solvent, which allows classifying the CGP/PVA film as pH sensitive stimuli-responsive material. The bioactivity was achieved through covalent immobilization of papain, which remained active after storage of CGP/PVA-papain film for 24h in the presence of buffer or in a dry form. These results evidenced that CGP/PVA-papain film is a very promising material for biomedical applications.

Development and optimization of a new culture media using extruded bean as nitrogen source.

The composition of a culture medium is one of the most important parameters to be analyzed in biotechnological processes with industrial purposes, because around 30-40% of the production costs were estimated to be accounted for the cost of the growth medium [1]. Since medium optimization using a one-factor-at-a-time approach is time-consuming, expensive, and often leads to misinterpretation of results, statistical experimental design has been applied to medium optimization for growth and metabolite production [2-5]. In this scenario, the use of mixture design to develop a culture medium containing a cheaper nitrogen source seems to be more appropriate and simple. In this sense, the focus of this work is to present a detailed description of the steps involved in the development of a optimized culture medium containing extruded bean as nitrogen source. •In a previous work we tested a development of new culture media based on the composition of YPD medium, aiming to reduce bioprocess costs as well as to improve the biomass production and heterologous expression.•The developed medium was tested for growth of Saccharomyces cerevisiae and Pichia pastoris (GS 115).•The use of culture media containing extruded bean as sole nitrogen source showed better biomass production and protein expression than those observed in the standard YPD medium.

A bioactive film based on cashew gum polysaccharide for wound dressing applications.

This work presents the development of a new bioactive material for wound therapeutics which may play a dual role of modulate metallo proteinases activity while prevents infection blocking out pathogenic microorganisms and foreign materials. A CGP/PVA film was activated by covalent immobilization of trypsin. Results from biocompatibility test revealed that PDL fibroblasts grown on the surface of CGP/PVA and the high amount of viable cells proved absence of cytotoxicity. Trypsin immobilized onto CGP/PVA film remained 100% active after 28 days stored dried at room temperature. In addition, CGP/PVA-trypsin film could be used for 9 cycles of storage/use without loss of activity. After immobilization, trypsin retained its collagenolytic activity, indicating this material as a promising material for wound dressing applications.

Rheological and biochemical properties of Solanum lycocarpum starch.

This study was conducted to evaluate the rheological and physicochemical properties of Solanum lycocarpum starch. The thermogravimetric analysis of S. lycocarpum starch showed a typical three-step weight loss pattern. Microscopy revealed significant changes in the granule morphology after hydrothermal treatment. Samples hydrothermally treated at 50°C for 10 min lost 52% of their crystallinity, which was recovered after storage for 7 days at 4°C. However, samples hydrothermally treated at 65°C were totally amorphous. This treatment was sufficient to completely disrupt the starch granule, as evidenced by the absence of an endothermic peak in the DSC thermogram. The RVA of S. lycocarpum starch revealed 4440.7cP peak viscosity, 2660.5cP breakdown viscosity, 2414.1cP final viscosity, 834.3cP setback viscosity, and a pasting temperature of 49.6°C. The low content of resistant starch (10.25%) and high content of digestible starch (89.78%) in S. lycocarpum suggest that this starch may be a good source for the production of hydrolysates, such as glucose syrup and its derivatives.

Development of culture medium using extruded bean as a nitrogen source for yeast growth.

In this study extruded bean was used as a nitrogen source substitute in culture medium formulation. A 3-factor simplex-lattice mixture design was used to establish better growth conditions. Completely substituted medium resulted in 43% of increase in the growth of Saccharomyces cerevisiae. Mixtures containing 1% extruded bean and 1% yeast extract, or 1% extruded bean and 1% peptone presented growths of 76-79% higher than the commercial YPD medium for S. cerevisiae. Pichia pastoris (GS115) growth was enhanced by 20% using a completely substituted medium. The protein expression patterns in P. pastoris (GS115) remained unchanged when growth was conducted in a medium containing extruded bean as unique nitrogen source. The total amount of recombinant protein expressed in extruded bean medium was 88.5% higher than in control expression medium. These results evidenced that extruded bean can be successfully used as a substitute of peptone and yeast extract in culture media for S. cerevisiae's and P. pastoris' (GS115) growth.

Lipase entrapment in PVA/Chitosan biodegradable film for reactor coatings.

This study reports the development and characterization of novel biodegradable film, based on chitosan and polyvinyl alcohol containing lipase entrapped. The films showed a thickness of 70.4 and 79 µm to PVA/Chitosan and PVA/Chitosan/Lipase, respectively. The entrapment of lipase in PVA/Chitosan film resulted in increasing of 69.4% tensile strength (TS), and 52.4% of elongation. SEM images showed the formation of a continuous film, without pores or cracks. The lipase entrapment efficiency was estimated in 92% and the films were repeatedly used for 25 hydrolytic cycles, maintaining 62% of initial activity. The PVA/Chitosan/Lipase film was used for olive oil hydrolysis of high performance. These results indicate that PVA/Chitosan/Lipase is a promising material for biotechnology applications such as triacylglycerol hydrolysis and biodiesel production.

Extraction and chemical characterization of starch from S. lycocarpum fruits.

In this study the pulp from Solanum lycocarpum fruits was used as raw material for extraction of starch, resulting in a yield of 51%. The starch granules were heterogeneous in size, presenting a conical appearance, very similar to a high-amylose cassava starch. The elemental analysis (CHNS) revealed 64.33% carbon, 7.16% hydrogen and 0.80% nitrogen. FT-IR spectroscopy showed characteristic peaks of polysaccharides and NMR analysis confirmed the presence of the α-anomer of d-glucose. The S. lycocarpum starch was characterized by high value of intrinsic viscosity (3515 mPa s) and estimated molecular weight around 645.69 kDa. Furthermore, this starch was classified as a B-type and high amylose content starch, presenting 34.66% of amylose and 38% crystallinity. Endothermic transition temperatures (To=61.25 °C, Tp=64.5 °C, Tc=67.5 °C), gelatinization temperature (ΔT=6.3 °C) ranges and enthalpy changes (ΔH=13.21 J g(-1)) were accessed by DCS analysis. These results make the S. lycocarpum fruit a very promising source of starch for biotechnological applications.

Chitin hydrolysis assisted by cell wall degrading enzymes immobilized of Thichoderma asperellum on totally cinnamoylated D-sorbitol beads.

In this study, cell wall degrading enzymes produced by Thrichoderma asperellum (TCWDE) were immobilized on totally cinnamoylated D-sorbitol (TCNSO) beads and used for chitin hydrolysis. In order to optimize immobilization efficiency, the reaction time was varied from 2 to 12 h and reactions were conducted in the presence or absence of Na2SO4. Immobilized enzymes were analysed concerning to thermal and operational stability. Immobilization in presence of Na2SO4 was 54% more efficient than immobilization in absence of salt. After optimization, 32% of the total enzyme offered was immobilized, with 100% of bounding efficiency, measured as the relation between protein and enzyme immobilized. Free and TCNSO-TCWDE presented very similar kinetics with maximum hydrolysis reached at 90 min of reaction. Thermal stability of both free and TCNSO-TCWDE was similar, with losses in activity after 55 °C. Moreover, free and TCNSO-TCWDE retained 100% activity after 3h incubation at 55 °C. TCNSO-TCWDE were used in a bath-wise reactor during 14 cycles, producing 1825 µg of N-acetylglucosamine (NAG) maintaining 83% of initial activity.

Biodegradable and bioactive CGP/PVA film for fungal growth inhibition.

In this study, chitinolytic enzymes produced by Trichoderma asperellum were immobilized on a biodegradable film manufactured with a blend of cashew gum polysaccharide (CGP) and polyvinyl alcohol (PVA), and tested as a fungal growth inhibitor. The film was produced by casting a blend of CGP and PVA solution on glass molds. The CGP/PVA film showed 68% water solubility, tensile strength of 23.7 MPa, 187.2% elongation and 52% of mass loss after 90 days in soil. The presence of T-CWD enzymes immobilized by adsorption or covalent attachment resulted in effective inhibition of fungal growth. Sclerotinia sclerotiorum was the most sensitive organism, followed by Aspergillus niger and Penicillium sp. SEM micrograph showed that the presence of immobilized T-CWD enzymes on CGP/PVA film produced morphological modifications on vegetative and germinative structures of the microorganisms, particularly hyphae disruption and changes of spores shape.

Wheat bread enrichment with hard-to-cook bean extruded flours: nutritional and acceptance evaluation.

This study describes the enrichment of wheat bread with hard-to-cook black bean (BBEF) and cowpea (CEF) extruded flours. Breads containing 10% BBEF and 10% CEF presented increase of, respectively, 9% and 10% in protein content. In addition the fiber content was 2.6 higher in 10% BBEF bread and 2.2 higher in 10% CEF bread in comparison with standard bread. Despite protein and fiber increasing, the energetic value of substituted breads remained unchanged. An increase in the substitution to 15% resulted in decrease of specific volume and density of the breads. Results of sensory analysis to 10% BBEF bread presented overall appearance scores higher than standard bread and overall flavor acceptance very similar to standard. A total of 10% CEF bread presented similar appearance to those standard bread and 73% overall flavor acceptance. It is interesting to point out that distribution of 10% CEF bread overall flavor scores showed 3 distinct levels of consumer's sensibility. Practical Application: Breads enriched with extruded bean flours presented fiber and protein content improved and a very good consumer's acceptance. These results indicate that extruded bean flours constitute ingredients nutritionally and economically viable for technological application in breads elaboration, conferring improvement of nutritional characteristics without changing sensory attributes.