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Food processing produces large volumes of waste that can be transformed into useful and relevant ingredients. The by-product of oil extraction from faveleira seeds is a potentially low-cost raw material that can be used for obtaining functional foods. This study aimed to analyze the physicochemical properties, chemical composition, and antioxidant activity of faveleira (Cnidoscolus quercifolius Pohl) seed press cake flour (FSPCF). Additionally, the chemical composition, antioxidant activity, and physical, microbiological, and sensory aspects of cookies with 0, 25%, or 50% substitution of refined wheat flour (RWF) with FSPCF (0-FSPCF, 25-FSPCF, and 50-FSPCF cookies, respectively) were evaluated.FSPCF exhibited good physicochemical properties, high antioxidant activity (0.45 ± 0.00 and 42.83 ± 1.30 g TE gFaveleira flour possesses high nutritional and bioactive value and can be used as a functional ingredient in cookies and possibly in other bakery products such as bread, cakes, and pastas. © 2022 Society of Chemical Industry.

This work aimed to evaluate the effects of ultrasound pretreatment on the microstructure, antioxidant activity, and carotenoid retention of biofortified Beauregard sweet potato (BBSP). The pretreatment was carried out in an ultrasonic bath at 30 °C for 10 min, and it was evaluated in terms of water loss and solid gain. The drying process was performed at two different temperatures (50 and 70 °C). Six different semi-theoretical mathematical models were examined to characterize the drying curves, and quality analyses were executed. The two-terms exponential model provided the best simulation of the drying curves. Drying time was reduced by performing ultrasound pretreatment and by increasing drying temperature. The ultrasound treatment caused greater agglomeration, breakage, or strangulation of the BBSP structure, increasing porosity, and thus increasing drying rates. Drying caused a diminution of total carotenoids content and influenced antioxidant activity. However, the samples pretreated with ultrasound and dried produced lower total carotenoids loss.

This study aimed to verify the action of edible chitosan–citric acid (CHI–CA) coating to control Colletotrichum gloeosporioides and maintain quality parameters of fresh-cut guava. Chitosan was obtained from Litopenaeus vannamei shells using high temperature and short exposure times. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of CHI–CA against C. gloeosporioides were determined by macrodilutions at 28 °C/120 h in the absence/presence of CHI–CA (0–10 mg/mL). Scanning electron microscopy was used to evaluate morphological changes in the fungus. Guava slices were coated with CHI–CA (MIC) or 5 mg/mL glycerol (control). Rot incidence and physicochemical, physical, and microbiological factors were determined at 0, 3, 7, and 14 days at 24 °C and 4 °C. Chitosan presented typical structural characterization, 64% deacetylation, and a molecular weight of 1.6 × 104 g/mol. CHI–CA exhibited MIC and MFC values of 5 mg/mL and 10 mg/mL, respectively, and promoted changes in the morphology and cell surface of fungal spores. The fresh-cut guava coated with CHI–CA maintained quality parameters during storage and preserved their sensorial characteristics. Therefore, the use of CHI–CA as a coating is a promising strategy for improving postharvest quality of fresh-cut fruits.

This study developed a palatable, acceptable, and functional mixed juice of pineapple (Ananas comosus var. Comosus), passion fruit (Passiflora edulis flavicarpa degener), and yacon (Smallanthus sonchifolius), with enhanced bioactive and prebiotic compounds. The ideal proportion of fruit and yacon was derived after planning a mixture with six formulations and by evaluating their bioactive compounds and organic acid profile. The best formulation sensory evaluation was performed by the Just-About-Right test (JAR) and global acceptance. The chosen mixed juice (M6 - 30% pineapple, 45% passion fruit, and 30% yacon) presented results that showed elevated levels of antioxidant activity (82.5% DPPH* inhibition), carotenoids (0.97 mg.100g-1), and total polyphenols (70.28 mg.100g-1). Total flavonols (23.95 mg.100g-1), total anthocyanins (1.37 mg.100g-1), gallic acid (3.13 μg.mL-1), quercetin (2.25 μg.mL-1), syringic acid (1.01 μg.mL-1), citric acid (949.30 mg.100g-1), malic acid (140.35 mg.100g-1), and 0.58% of dietary fiber were also reported. Sensorially, consumers perceived high acidity, strong flavor, and a fibrous texture, which might have affected the global acceptance of the juice (6.0). Results indicated the feasibility of obtaining a functional and palatable mixed juice using yacon. RESUMO: Este estudo objetivou desenvolver suco misto funcional, palatável e aceitável de abacaxi (Ananas comosus var. Comosus), maracujá (Passiflora edulis flavicarpa degenerer) e yacon (Smallanthus sonchifolius), enriquecido com compostos bioativos e prebióticos. A proporção ideal entre as frutas e o yacon foi resultado de planejamento de mistura com seis formulações e avaliação de perfil de compostos bioativos e ácidos orgânicos. A melhor formulação foi avaliada sensorialmente pelo teste Just About Right (JAR) e por aceitação global. O suco misto escolhido (M6 - 30% de abacaxi, 45% de maracujá e 30% de yacon) apresentou altos valores para atividade antioxidante (82,5% de inibição de DPPH *), carotenoides (0,97 mg/100g) polifenóis totais (70,28 mg/100g). Também foram detectados flavonóis totais (23,95 mg/100g), antocianinas totais (1,37 mg/100g), ácido gálico (3,13 μg/mL), quercetina (2,25 μg/mL), ácido siríngico (1,01 μg/mL), ácido cítrico (949,30 mg/100g), ácido málico (140,35 mg/100g) e 0,58% de fibra alimentar. Sensorialmente, os consumidores perceberam alta acidez, sabor forte e textura fibrosa, o que pode ter afetado a aceitação global (6,0). Os resultados indicam a possibilidade de obtenção de um suco misto funcional e palatável com yacon.

The aim of the present study was to formulate toothpastes containing biosurfactants and either fungal chitosan or sodium fluoride and evaluate the cytotoxicity, antimicrobial action and inhibition potential against biofilm formed by Streptococcus mutans. Chitosan was extracted from the biomass of the fungus Mucorales. We tested biosurfactants produced by Pseudomonas aeruginosa UCP 0992 (PB), Bacillus metylotrophicus UCP 1616 (BB) and Candida bombicola URM 3718 (CB). Fractional inhibitory concentration analysis was performed to determine the type of interaction between the compounds. Six toothpaste were prepared, the active ingredients of which were the biosurfactants, chitosan or sodium fluoride. The cytotoxicity tests were performed using the 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay for the L929 (mouse fibroblast) and RAW 264.7 (mouse macrophage) cell lines. The toothpastes were tested with regard to pH, consistency and foaming capacity. The inhibition of biofilm was investigated by applying the toothpaste to biofilm formed in modified artificial saliva for 24 h at 37 °C in anaerobiosis. All substances had a minimum inhibitory concentration (MIC) for S. mutans. The combinations of CB and PB with chitosan had an additive effect against S. mutans, whereas BB combined with chitosan had an indifferent effect. The toothpastes were non-toxic. The formulations had pH around 9, spreading capacity between 8 and 17 mm and foaming capacity between 63 and 95%. All formulations inhibited the cellular viability of S. mutans in the biofilm, with similar results compared to the commercial toothpaste tested. The present results show that the formulations suggested are promising when compared to a commercial tooth paste.

The aim of the present study was to determine the antimicrobial action and toxicity of mouthwashes formulated with a biosurfactant, chitosan of a microbial origin and peppermint (Mentha piperita) essential oil (POE). Chitosan was extracted from the biomass of a fungus from the order Mucorales grown in yam bean broth. Three biosurfactants produced by Pseudomonas aeruginosa UCP 0992 (PB), Bacillus cereus UCP 1615 (BB) and Candida bombicola URM 3718 (CB) were tested. Six mouthwashes were prepared, the active ingredients of which were the biosurfactant, chitosan and POE. The minimum inhibitory concentration (MIC) was determined for the test substances separately, in combinations and in the mouthwash formulas. The toxicity of the mouthwashes was tested using MTT (3-(4,5-dimethylthiazole-2-il)-2,5-diphenyltetrazolium bromide) for the L929 (mouse fibroblast) and RAW 264.7 (mouse macrophage) cell lines. All substances tested had a MIC for cariogenic microorganisms. The combinations of the CB and PB biosurfactants with chitosan demonstrated an additive effect on the majority of microorganisms tested. The toxicity of the mouthwashes was significantly lower than that of the commercial mouthwash. The present findings demonstrate that mouthwashes containing natural products constitute a safe, effective, natural alternative to commercially available mouthwashes for the control of oral microorganisms.

This research verified the behavior of Lactobacillus rhamnosus and Lactobacillus casei added to ice cream in free form or encapsulated with alginate-chitosan by comparing their: (1) resistance to low temperature; (2) encapsulation efficiency and (3) cell survivability in a simulated gastrointestinal environment. Calcium alginate-chitosan capsules were produced by extrusion method. The ice cream samples with probiotics were stored at −18 °C for 150 days, and the pH, titratable acidity, the cell viability of the probiotics and the gastrointestinal simulation were analyzed. Free L. casei (−1.64 log) were more resistant to freezing than free L. rhamnosus (−1.92 log). L. rhamnosus and L. casei presented encapsulation efficiencies of 73.8% and 79.5%, respectively. In the gastrointestinal simulation, 86.2% L. rhamnosus (−0,83 log) and 84% L. casei (−1,3 log) were protected by the alginate-chitosan capsules. The results demonstrated that microcapsules reduce cell loss in frozen storage and in simulated gastrointestinal conditions. The reduction in cell viability of encapsulated L. rhamnosus was superior to that of its free form, showing that the encapsulation process is not advantageous for all probiotic species. Therefore, considering cellular losses, the best option for preparing functional yellow mombin ice cream is to use free L. rhamnosus or encapsulated L. casei.

This work aimed to evaluate the effects of ultrasound pretreatment on the microstructure, antioxidant activity, and carotenoid retention of biofortified Beauregard sweet potato (BBSP). The pretreatment was carried out in an ultrasonic bath at 30 °C for 10 min, and it was evaluated in terms of water loss and solid gain. The drying process was performed at two different temperatures (50 and 70 °C). Six different semi-theoretical mathematical models were examined to characterize the drying curves, and quality analyses were executed. The two-terms exponential model provided the best simulation of the drying curves. Drying time was reduced by performing ultrasound pretreatment and by increasing drying temperature. The ultrasound treatment caused greater agglomeration, breakage, or strangulation of the BBSP structure, increasing porosity, and thus increasing drying rates. Drying caused a diminution of total carotenoids content and influenced antioxidant activity. However, the samples pretreated with ultrasound and dried produced lower total carotenoids loss.

The effect of microencapsulation of L. acidophilus La-05 (8 log CFU/mL) by external ionic gelation technique in alginate (30 g/L; AM) and alginate coated with a low molecular weight chitosan solution (5 g/L; AC5M) on the survival of the freeze-dried probiotic culture during storage (7 °C; 0, 7, 15, 30, 60, 90 and 120 days), and exposure to temperature (72, 85 and 90 °C), pH (2, 4, and 6), and NaCl (10, 15 and 20 g/L) were studied. Furthermore, vegan milks (soybean and rice milks) added with microencapsulated probiotic cultures were evaluated for the physicochemical characteristics and survival of the probiotic culture during refrigerated storage (7 °C; 7 days) and in vitro digestion. Free cells were used as control. AM and AC5M showed similar microencapsulation yield (>90%) with uniform and spherical microparticles dispersed without agglomeration. Scanning electron microscopy showed that chitosan was able to cover the porous structure of the alginate particles, resulting in a more stabilized microparticle. The microencapsulation provided higher probiotic protection to storage, thermal treatment, NaCl and pH (decreases of ~1 log CFU/mL) compared to the free cells (decreases of ~3, 4, 2 and 3 log CFU/mL, respectively), and increased probiotic survival during refrigerated storage and in vitro digestion of vegan milks compared to free cells (decreases of ~1 and 4 log CFU/mL, respectively). Only microencapsulated probiotic cultures (AM and AC5M) maintained suitable probiotic counts (>6 log CFU/mL) during storage, exposure to stress conditions and simulated gastrointestinal digestion. Chitosan coating increased the probiotic survival in the vegan milks during refrigerated storage. Microencapsulation by external ionic gelation in alginate proved to be a suitable microencapsulation technique to improve the probiotic survival to storage, stress conditions (temperature, pH and NaCl) and simulated gastrointestinal conditions. This was the first study that evaluated the addition of probiotic cultures to rice and soybean milks, proving that the vegan milks could be considered suitable carriers for microencapsulated probiotic cultures.

Faveleira (Cnidoscolus quercifolius) is an emerging Brazilian plant, with seeds rich in edible oil. This study investigates physicochemical properties, chemical composition, thermal and oxidative stability, in vitro and in vivo toxicity, antioxidant, antinociceptive and anti-inflammatory activities of faveleira seed oil. It was observed that the oil has low acidity, value of peroxide, chlorophyll, carotenoids, β-carotene and high concentrations of unsaturated fatty acids. In addition to presenting thermal and oxidative stability and high total phenolic content, with vanillin, eugenol and quercetin were predominating. The oil showed no toxicity in vitro and in vivo, and presented antioxidant, anti-inflammatory and antinociceptive activities. These findings provide relevant and appropriate conditions for processing of faveleira seed oil as functional food.

This study compared, for the first time, the postharvest conservative action of edible fungal chitosan coatings (gel, nanoparticles and gel-nanoparticle) on the physico-chemical, sensorial and microbiological characteristics of strawberries. The nanoparticles were prepared by an ionic gelation method and characterized by dynamic light scattering and scanning electron microscopy. The antioxidant (DPPH* and ABTS*) activity of the edible coatings and the antimicrobial (macrodilution method) action against phytopathogenic fungi were verified. The nanoparticles had a size of 331.1 nm and a zeta potential of+ 34 mV. The gel, nanoparticles and gel+nanoparticles exhibited minimum inhibitory concentration values ranging from 4 to 5, 1.5 to 2.5 and 1.0 + 0.5 to 2.0 + 1.5 g.L-1, respectively. All the edible coatings exhibited antifungal action. All the coatings had high scavenging activity, especially the gel edible coating. The coatings, especially the gel+nanoparticles, decreased the weight loss, microbiological growth, soluble solids, maturity index and moisture loss of the strawberry and preserved the pH values, anthocyanin content, titratable acidity and sensory characteristics. Therefore, the use of chitosan edible coating containing nanoparticles can be a promising strategy to improve the post-harvest quality of strawberries.

Chitosan edible coatings are a potential alternative for extending the postharvest life of fruit. The properties of chitosan can be enhanced when it is used in the form of nanoparticles. The aim of this study was to evaluate the in vitro antimicrobial activity and the effect of gel + fungal chitosan nanoparticles on some physicochemical properties (total soluble solids, pH, titratable acidity, reducing sugar content and moisture content) and sensory characteristics of grapes stored at 12 °C and 25 °C. The chitosan nanoparticles were prepared by ionic gelation and then underwent a heat treatment (50 °C/1200 × g/30 min). Characterization of the particles was carried out by dynamic light scattering and scanning electron microscopy. The microdilution test was used to determine the minimum inhibitory (MIC) and bactericidal concentration (MBC) of chitosan nanoparticles against food-borne pathogenic bacteria. To obtain the coatings to be tested, chitosan was solubilized in 1% acetic acid (20 g/L−1) and nanoparticles were subsequently added (MIC/2, MIC and 2MIC). The produced nanoparticles were spherical, had a medium size of 128.3 nm and showed an inhibitory effect against pathogenic foodborne bacteria with MIC values ranging from 2 to 3 g/L−1. The edible chitosan nanoparticle coatings were responsible for delaying the ripening process of the grapes resulting in decreased weight loss, soluble solids and reducing sugar contents as well as increased moisture retention and preservation of the titratable acidity values and sensory characteristics. Therefore, the use of edible coatings containing chitosan nanoparticles at different concentrations (MIC/2, MIC, 2MIC) can be a promising strategy to improve the post-harvest quality of grapes.

This study evaluated corn steep liquor (CSL) and papaya peel juice (PPJ) in mixture as substrates for the cultivation (96 h, 28 °C, pH 5.6, 150 rpm) of Mucorales fungi for chitosan production, and determined the growth-inhibitory effect of the fungal chitosan (FuCS) obtained under optimized conditions against phytopathogenic Colletotrichum species. All Mucorales fungi tested were capable of growing in CSL-PPJ medium, showing FuCS production in the range of 5.02 (Fennelomyces heterothalicus SIS 28) − 15.63 mg/g (Cunninghamella elegans SIS 41). Highest FuCS production (37.25 mg/g) was achieved when C. elegans was cultivated in medium containing 9.43% CSL and 42.5% PPJ. FuCS obtained under these conditions showed a deacetylation degree of 86%, viscosity of 120 cP and molecular weight of 4.08 × 104 g/mol. FuCS at 5000, 7500 and 10,000 ppm inhibited the growth of all Colletotrichum species tested. FuCS also induced alterations in the morphology of C. fructicola hyphae. CSL-PPJ mixtures are suitable substrates for the cultivation of Mucorales fungi for FuCS production. Chitosan from C. elegans cultivated in CSL-PPJ medium is effective in inhibiting phytopathogenic Colletotrichum species.

The purpose of this study was to evaluate the antimicrobial properties of a new formulation containing silver nanoparticles, named Nano Silver Fluoride (NSF), to inhibit Streptococcus mutans biofilm formation on children’s dental enamel. The variations in dental biofilm pH and in the Simplified-Oral-Hygiene-Index (OHI-S) also were evaluated after the treatment with NSF. This was a randomized, double-blind, crossover and prospective pilot clinical trial study in which 12 schoolchildren, aged between 7-8 years, had their dental enamel treated with two solutions: S1 - Nano Silver Fluoride and S2 - negative control (saline solution), in different experimental moments. The dental biofilm adhered to enamel treated with NSF had lower values of S. mutans viability (absorbance) and colony forming units (CFU) than the S0 (baseline) and S2. There was a statistically significant difference between the OHI-S mean values of S0 and S1. There were no differences between the biofilm pH (both before and after the use of the test substances) and among the different groups. These properties suggest that NSF has bactericidal effect against S. mutans biofilm and it may be used for clinical control and prevention of dental biofilm formation.