Cell rupture of Tetradesmus obliquus using high-pressure homogenization at the pilot scale and recovery of pigments and lipids.

Microalgae are promising sources of intracellular metabolites such as proteins, polysaccharides, pigments, and lipids. Thus, this study applied high-pressure homogenization (HPH) techniques on a pilot scale to disrupt the cells of Tetradesmus obliquus. The effects of pressure (P; 150, 250, and 350 bar), suspension concentration (Cs; 1.

Mathematical modeling for the prediction of biofilm formation and removal in the food industry as strategy to control microbiological resistance.

The formation of biofilms in the food industry poses significant economic, social, and public health challenges. Concurrently, mathematical models have emerged as promising tools for investigating microbial contamination and biofilm dynamics. This study evaluates the application of these models, highlighting their ability to identify critical parameters influencing microbial adhesion and to develop strategies for disrupting biofilm formation.

Delivery and controlled release abilities of chitosan/carboxymethylcellulose micropolyelectrolyte complexes (PECs) toward niacinamide (vitamin B3).

The administration of bioactive compounds presents challenges due to the numerous physiological barriers in the gastrointestinal tract. To deal with one of these challenges, chitosan (CHS)/carboxymethylcellulose (CMC) micropolyelectrolyte complexes (micro-PECs) were developed without the use of crosslinking agents to carry niacinamide, a model hydrophilic bioactive agent. A Box-Behnken design was used to study the effects of processing time (X = 60, 120 or 180 min), pH (X = 3, 4 or 5) and niacinamide concentration (X = 0.

Chitosan/carboxymethylcellulose polyelectrolyte complexes (PECs) are an effective material for dye and heavy metal adsorption from water.

Granular macroscopic chitosan/carboxymethylcellulose polyelectrolytic complexes (CHS/CMC macro-PECs) were produced and tested as adsorbents for six pollutants often present in wastewaters: sunset yellow (YS), methylene blue (MB), Congo red (CR) and safranin (S), cadmium (Cd) and lead (Pb). The optimum adsorption pH values at 25 °C were 3.0, 11.

Stabilization of oil-water emulsions with protein concentrates from the microalga .

The present work used water-soluble protein concentrates from the microalga to stabilize sunflower oil emulsions. Microalgal cells were disrupted by sonication, and proteins were separated from the biomass using two methods, isoelectric and solvent precipitations. The protein extracts were concentrated by lyophilization, and the concentrates were used to produce emulsions with three amounts of protein concentrate (TobPC) (0.

Obtention and evaluation of physico-chemical and techno-functional properties of macauba (Acrocomia aculeata) kernel protein isolate.

The consumption of plant proteins is increasing worldwide. These proteins have an important role in human nutrition as well as in the technological properties of foods. Thus, there is a great interest in exploring new sources of plant proteins, such as macauba (Acrocomia aculeata), which is a promising tropical palm tree, native to Brazil, whose fruits are rich in oil, proteins and dietary fiber.

Ultrasound-assisted enzymatic hydrolysis of goat milk casein: Effects on hydrolysis kinetics and on the solubility and antioxidant activity of hydrolysates.

This study evaluated the ability of ultrasound (US) bath to improve the hydrolysis of goat milk casein (GMC) by three commercial proteases (Alcalase, Brauzyn and Flavourzyme) using assisted reactions at 60 °C for up to 300 min. Process performance was evaluated based on the rate reaction, final hydrolysis degree, solubility, and antioxidant activity of the hydrolysates. For all enzymes, the US-assisted reaction increased the rate of GMC hydrolysis (up to 120%), the hydrolysis degree (23-48%), and the small peptides formed, i.

Impacts of Ca cation and temperature on bovine α-lactalbumin secondary structures and foamability - Insights from computational molecular dynamics.

We used computational molecular dynamics (MD) to assess molecular conformations of apo- and holo-forms (respectively without and with Ca) of bovine α-lactalbumin (α-La) at different temperatures, and to correlate them with the protein's foaming properties. At 4 °C and 25 °C no major protein conformation changes occurred. At 75 °C, lots of changes were evidenced: the Ca depletion triggered the complete loss of h2b, h3c helices and S1, S2 and S3 β-sheets, and partial losses of H1, H2 and H3 α-helices.

Influence of Homogenization in the Physicochemical Quality of Human Milk and Fat Retention in Gastric Tubes.

Background: The retention of human milk nutrients in gastric tubes used to feed premature infants is a challenge to be overcome.

Research Aims: To evaluate (1) the performance of six homogenizers (mixing processor, piston valve, ultrasonic bath, ultraturrax, stirring mixer, and ultrasound probe) for the fat retention reduction in gastric tubes; (2) the influence of the best homogenization conditions on the fatty acid and protein profiles of human milk; and (3) the cost/benefit ratio for the inclusion of homogenization as a new step in human milk processing.

Methods: The influence of different levels and times of homogenization on reducing fat retention of human milk in probes was evaluated in this comparative prospective cross-sectional study.

Aqueous solutions of glycolic, propionic, or lactic acid in substitution of acetic acid to prepare chitosan dispersions: a study based on rheological and physicochemical properties.

Chitosan (CH) is a biopolymer derived from chitin, which is the second most abundant polysaccharide in nature, after cellulose. Their functional groups -NH and -OH can form intermolecular interactions with water and other molecules, enabling a variety of applications for CH. -NH groups become protonated in acidic solutions, causing an increase in electrostatic repulsion between CH chains, which facilitates their dispersion in aqueous media.

Mixed starch/chitosan hydrogels: elastic properties as modelled through simulated annealing algorithm and their ability to strongly reduce yellow sunset (INS 110) release.

Biopolymers mixtures appear as a strategy to improve sensorial/technological characteristics of gel-like products. Thus, self-sustaining starch (S100/C0) hydrogels were prepared with a partial replacement of the gelling agent by 5.0 % (S95/C5), 7.

Structural and molecular bases of angiotensin-converting enzyme inhibition by bovine casein-derived peptides: an molecular dynamics approach.

The angiotensin-converting enzyme (ACE) plays a key role in blood pressure regulation process, and its inhibition is one of the main drug targets for the treatment of hypertension. Though various peptides from milk proteins are well-known for their ACE-inhibitory capacity, research devoted to understand the molecular bases of such property remain scarce, specifically for such peptides. Therefore, in this work, computational molecular docking and molecular dynamics calculations were performed to enlighten the intermolecular interactions involved in ACE inhibition by six different casein-derived peptides (FFVAPFPEVFGK, FALPQYLK, ALNEINQFYQK, YLGYLEQLLR, HQGLPQEVLNENLLR and NAVPITPTLNR).

Nanostructured conjugates from tara gum and α-lactalbumin. Part 1. Structural characterization.

Nanostructures from conjugates of tara gum and α-lactalbumin were obtained via the heat-gelation process with pH adjustment. The conjugates were produced by Maillard reaction using the dry-heating method in lyophilized or spray-dried mixtures of TG and α-la and were characterized by browning index (BI) and percentage of free amino groups (% FAG). Nanostructured systems were characterized by dynamic light scattering, ζ-potential, circular dichroism, and intrinsic fluorescence to evaluate the structures.

Chitosan dispersed in aqueous solutions of acetic, glycolic, propionic or lactic acid as a thickener/stabilizer agent of O/W emulsions produced by ultrasonic homogenization.

Chitosan is a natural polycationic polysaccharide with several known biotechnological functionalities, but its application in food products as ingredient or additive remains nowadays unusual. Additionally, ultrasonic production of food-grade emulsions is still an open research field, so ultrasound applicability for such purpose must be evaluated case by case. In this study, chitosan was dispersed in acid aqueous media containing acetic, glycolic, propionic or lactic acid (50 mmol·L), then added of the emulsifier Tween 20, and finally mixed to sunflower oil, through ultrasonic homogenization (20 kHz, 500 W, 4 min), in order to prepare O/W emulsions (oil fraction = 0.

Use of gelatin and gum arabic for microencapsulation of probiotic cells from Lactobacillus plantarum by a dual process combining double emulsification followed by complex coacervation.

The objectives of this study were i) to microencapsulate probiotic cells of Lactobacillus plantarum through a dual process consisting of emulsification followed by complex coacervation using gelatin and gum arabic, ii) to characterize the lyophilized microcapsules, iii) to evaluate their behavior in simulated in vitro gastrointestinal conditions and iv) to evaluate the survival of microencapsulated probiotic cells during 45 days of storage at 8 °C, 25 °C and -18 °C. The optimized conditions for complex coacervation consisted of a 50:50 biopolymer ratio and pH = 4.0.

Insights on physicochemical aspects of chitosan dispersion in aqueous solutions of acetic, glycolic, propionic or lactic acid.

Chitosan is a polysaccharide well-known for its applicability as a biocompatible, biodegradable, and non-toxic material to produce drugs excipients and food coatings. Acidic media are required to disperse chitosan, and aqueous solutions of acetic acid have been typically used for this purpose. However, this acid has several sensory drawbacks.

Engineered GH11 xylanases from Orpinomyces sp. PC-2 improve techno-functional properties of bread dough.

Background: Endo-1,4-β-xylanases have marked hydrolytic activity towards arabinoxylans. Xylanases (xynA) produced by the anaerobic fungus Orpinomyces sp. strain PC-2 have been shown to be superior in specific activity, which strongly suggests their applicability in the bakery industry for the processing of whole-wheat flour containing xylans.

Increased thermal stability of anthocyanins at pH 4.0 by guar gum in aqueous dispersions and in double emulsions W/O/W.

This study investigated the potential of guar gum and a double emulsion to increase the thermal stability of anthocyanins. The effect of different guar gum concentrations (0%, 0.25%, 0.

Optimization of pectin extraction from Ubá mango peel through surface response methodology.

A central composite design was used to determine effects of pH (1.16-2.84), extraction temperature (63-97°C) and time (35-85min) on the yield, degree of degree of esterification (DE) and viscosity of pectins extracted.

Anti-Hypertensive Peptides Derived from Caseins: Mechanism of Physiological Action, Production Bioprocesses, and Challenges for Food Applications.

This review is focused on the state-of-art of peptides with inhibitory activity towards angiotensin I-converting enzyme (ACE) - thus, with anti-hypertensive potential - derived from enzymatic hydrolysis of caseins. Firstly, molecular characteristics of caseins relevant to a better understanding of this subject were concisely commented. Next, a brief description of the pathophysiology of hypertension was explained, focusing on the ACE role in regulation of blood pressure in human body.

Formation and characterization of supramolecular structures of β-lactoglobulin and lactoferrin proteins.

Combination of β-lactoglobulin (β-Lg) and lactoferrin (Lf), biomacromolecules derived from bovine whey, was used in the formation of supramolecular structures by thermal gelation technique to adjust the pH. Furthermore, the influence of the molar ratio, temperature, pH, and heating time in the formation of supramolecular structures were also studied. The characterization of the protein supramolecular structures was performed using dynamic light scattering, zeta potential measurements, molecular spectrofluorimetry, and circular dichroism spectroscopy.

Acacia gum as modifier of thermal stability, solubility and emulsifying properties of α-lactalbumin.

Protein-polysaccharide conjugates often display improved techno-functional properties when compared to their individual involved biomolecules. α-Lactalbumin:acacia gum (α-la:AG) conjugates were prepared via Maillard reaction by the dry-heating method. Conjugate formation was confirmed using results of absorbance, o-phthalaldehyde test, sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE) and size exclusion chromatography.

Recovery of casein-derived peptides with in vitro inhibitory activity of angiotensin converting enzyme (ACE) using aqueous two-phase systems.

Peptides inhibiting the activity of angiotensin converting enzyme (ACE) were obtained by trypsin-catalyzed hydrolysis of bovine milk casein, performed at 37°C, during 1, 2, 5, 8 and 24h. Results of in vitro inhibitory activity ranged between 13.4% and 78.