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•The capsules with up to 50 % extract present uniform morphology and thermal stability.•The encapsulated extracts have without toxicity to astrocyts.•The encapsulated extracts showed ...selective antitumor effect against glial tumor cells.
Gliomas, intracranial malignant tumors, are aggressive, asymptomatic and difficult to treat due to their degree of infiltration, alternatives are needed to treat the disease. In this sense, natural compounds from the specialized metabolism of plants can act to control the disease. Glucosinolates and phenolic compounds, present in broccoli, have a potential to promote tumor cell death, however due to the low stability of these compounds, encapsulation becomes an alternative for their preservation. The objective was to encapsulate the broccoli extract by electrospraying and to evaluate its cytotoxicity in the primary cell culture of astrocytes and gliomas. The capsules were produced and characterized by encapsulation efficiency, functional groups, thermal stability and morphology, the capsule that presented the best parameters was used for the evaluation of cell cytotoxicity and antitumor activity. Capsules with equal or less than 50 % extract showed high encapsulation efficiency, high thermal stability and uniform morphology due to non-saturation of the active zein sites, which allowed a complete encapsulation of the added extract, as well as a greater protection of the compounds. The capsule with 50 % of the extract showed good results of the efficiency, morphology and thermal stability and was used to evaluate the antitumor activity, since the addition of extract in proportions greater than 60 % promoted saturation of the active sites and lower encapsulation efficiency, and directly affects the morphology and thermal stability. The encapsulated and unencapsulated extracts showed strong selective antitumor effect against glial tumor cells without toxicity to non-tumor cells.
The need for biodegradable and innovative nanomaterials in the food packaging industry motivates the conduction of studies on the production and characterization of new nanomaterials. The aim of this ...study was to evaluate the encapsulation efficiency (EE), thermal resistance, and antioxidant and antimicrobial activities of carvacrol encapsulated in potato starch nanofibers. The nanofibers possessed low EE (26%–33%) and high thermal resistance, showing residual carvacrol quantities after exposure to high temperatures. They also showed reduced but stable inhibition of DPPH oxidation compared with free carvacrol (20%, 33%, and 52% for the nanofibers with 20%, 30%, and 40% carvacrol, respectively) and OH inhibition varying from 4% to 18% for the nanofibers in general. Moderate antimicrobial activity (0.98 mg/ml) was found for all nanofibers throughout minimal inhibitory concentration (MIC) values. Our findings highlight the potential of starch/carvacrol nanofibers for application in the food sector as an antimicrobial and antioxidant agent.
Practical applications
The nanomaterial developed in this study can be applied in the elaboration of active food packages, which can act as antioxidants and/or antimicrobial agents. The end use includes packages that undergo high temperatures in their production. In addition, the packages containing the starch/carvacrol nanofibers can preserve several types of food products.
Phenolic compounds were extracted from biphasic olive pomace and their biological potential was characterised. Two different extracts were prepared, E1 (40% methanol) and E2 (80% methanol), both ...subjected to agitation (180 min) and 70 °C. LC-ESI-qTOF-MS was used for individual quantification of the extracted phenolic compounds. The antioxidant activity was determined using different methods, including nitric oxide, DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl radical. The enzymes α-amylase and α-glucosidase were used to evaluate the antihyperglycemic potential and sulforhodamine B and MTT (tetrazolium salt) for antitumor activity. To evaluate the antimicrobial activity, minimum inhibitory concentration and minimum bactericidal concentration of the extracts, the disc diffusion technique was used. Among the phenolic compounds present, tyrosol was highlighted in both extracts, as well as the anti-hyperglycemic effects, antitumor action and antioxidant activity. The antimicrobial activity found in the extracts was considered moderate to weak.
Starch is considered an important ingredient in the preparation of safe food. Current study investigates the physicochemical, morphological, thermal and pasting properties of rice starches, subjected ...to HMT at 13 g/100 g moisture, at different treatment times (10, 30 and 60 min), directly in the grain paddy rice and in the isolated starch. HMT reduced extraction yield of rice starch with increasing HMT time. The HMT starches had lower gelatinisation enthalpy when compared to native starch. HMT in grain reduced extraction yield of starch by the alkaline method with increasing time of exposure to high temperatures, altering the structure of starch-protein. The HMT in grains decreases the setback of the isolated starches, due to amylose-lipid complexation induced by high temperatures applied on modification. The hydrothermal treatment increased the mechanical and thermal stability of rice starches and promoted the strengthening of links, forming a more stable structure.
•Rice grains and isolated starch were submitted to HMT at 13 g/100 g moisture.•HMT reduces extraction yield of rice starch by the alkaline method.•HMT performed in grain or directly in starch affects differently the starch properties.•HMT effects on starches are intensified by treatment time.
The brassicas have the potential to prevent chronic non-communicable diseases and it is proposed to evaluate the chemical composition, antioxidant and antimicrobial potential of broccoli, cabbage and ...extracts. The extracts were prepared and characterized and the antioxidant potential was evaluated against three radicals while the antimicrobial potential was analyzed using three techniques against four bacteria. The extracts have glucosinolates and phenolic compounds in their composition, and effectively inhibit the 2,2-diphenyl-1-picrylhydrazyl radical. The extracts of broccoli and cauliflower showed an inhibitory effect against hydroxyl radicals and nitric oxide. Disk diffusion showed that broccoli and cauliflower extract were active against three bacteria, while kale extract showed active halos for Gram-negative bacteria. Kale extract had an inhibitory effect Gram-positive bacteria, cauliflower extract inhibited the growth of Staphylococcus aureus. The cauliflower extract thus had a higher concentration of phenols, a strong antioxidant activity and promising results at a concentration of 100 mg/mL against S. aureus.The brassicas have the potential to prevent chronic non-communicable diseases and it is proposed to evaluate the chemical composition, antioxidant and antimicrobial potential of broccoli, cabbage and extracts. The extracts were prepared and characterized and the antioxidant potential was evaluated against three radicals while the antimicrobial potential was analyzed using three techniques against four bacteria. The extracts have glucosinolates and phenolic compounds in their composition, and effectively inhibit the 2,2-diphenyl-1-picrylhydrazyl radical. The extracts of broccoli and cauliflower showed an inhibitory effect against hydroxyl radicals and nitric oxide. Disk diffusion showed that broccoli and cauliflower extract were active against three bacteria, while kale extract showed active halos for Gram-negative bacteria. Kale extract had an inhibitory effect Gram-positive bacteria, cauliflower extract inhibited the growth of Staphylococcus aureus. The cauliflower extract thus had a higher concentration of phenols, a strong antioxidant activity and promising results at a concentration of 100 mg/mL against S. aureus.
Minimally processed apples (MPA) are tasty, easy to consume, nutritious (sugars, vitamins and minerals) and functional (dietary fiber and secondary metabolites such as flavonoids, isoflavonoids, ...carotenoids and phenolic acids). However, following processing, pulp browning rapidly compromises its natural color, texture, flavor, and health benefits. To deal with this problem, refrigerated storage combined with antioxidant treatment is usually employed. In this study, kojic acid (KA), a metabolite of fungi (
Aspergillus
and
Penicillium
) widely used as a food additive to prevent enzymatic browning and bacterial growth, was used as an antioxidant. It was tested at three different concentrations (0.03%, 0.05% and 0.07%) in minimally processed ‘Royal Gala’ apples, for up to 9 days of cold storage. Distilled water and 0.6% L-cysteine chloride were used as negative and positive controls, respectively. Browning index, Hue angle, antioxidant activity, total phenolic compounds, enzyme activity (peroxidase and polyphenoloxidase) and sensory attributes were evaluated. The browning of ‘Royal Gala’ apples was dependent on KA concentration for all related variables (L*, a* e b*, Hue angle and browning index). KA at concentrations of 0.05% and 0.07% showed results similar to the positive control (L-cysteine). The values of total phenolic compounds and antioxidant activity were stable for apples treated with KA 0.07% during the 9 days of storage. The peroxidase activity of apples treated with KA 0.07% was similar to that of apples treated with L-cysteine 0.6%. Sensorial analysis showed that KA-treated apples scored better than L-cysteine-treated apples. KA 0.07% was effective in controlling the browning of ‘Royal Gala’ apple pulp, without altering the sensory characteristics during the 9 days of refrigerated storage.
Tannic acid (TA) exhibits low bioavailability in the gastrointestinal tract, limiting its benefits due to small amounts reaching the CNS. Thus, the objective of this study was to develop zein ...capsules and fibers by electrospraying/electrospinning for encapsulation of TA. Polymeric solutions were evaluated by electrical conductivity, density, and viscosity. In zein capsules, up to 2 % TA was added, and in fibers, up to 1 % TA was added. Zein capsule and fiber with TA were evaluated by morphology, size distribution, encapsulation efficiency, thermal and thermogravimetric properties, and functional groups. Zein capsule with 1.5 % TA was evaluated in astrocyte culture for cytotoxicity and antioxidant activity. TA zein capsules and fibers exhibited high encapsulation efficiency and homogeneous morphology. TA encapsulated in zein presented higher thermal stability than free TA. TA zein capsule did not present toxicity and elicited antioxidant action in lipopolysaccharide-induced astrocyte culture. Capsules and fibers were successfully produced by electrospraying/electrospinning techniques.
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•The zein capsules and fibers with TA were produced by electrospraying/electrospinning•The capsules and fibers presented high encapsulation efficiency and thermal stability.•The zein capsule with 1.5 % TA did not demonstrate toxicity in astrocyte culture.•TA zein capsule showed antioxidant activity in the LPS-challenged astrocyte culture.
The aim of this study was to develop a star fruit extract (SFE) and incorporate it into aerogels based on native and phosphorylated potato starches. The phosphorylation of starch enhances its ...properties by incorporating phosphate groups that increase the spaces between starch molecules, resulting in a more resilient, intact aerogel with enhanced water absorption. The bioactive aerogels based on potato starch and 10, 15, and 20 % (w/w) of SFE were characterized by their morphological and thermogravimetric properties, infrared spectra, water absorption capacity, loading capacity, and antioxidant activity. Epicatechin was the major compound present in SFE. The thermal stability of SFE increased when incorporated into phosphorylated starch aerogels at a concentration of 20 %. The water absorption capacity was higher in phosphorylated starch aerogels (reaching 1577 %) than in their native counterparts (reaching 1100 %). Native starch aerogels with 15 and 20 % SFE exhibited higher antioxidant activity against hydroxyl free radicals compared to phosphorylated starch aerogels, achieving 79.9 % and 86.4 % inhibition for the hydroxyl and nitric oxide radicals, respectively. The ideal choice of freeze-dried aerogel depends on the desired effect, either to act as an antioxidant agent by releasing bioactive compounds from SFE or as a water-absorbent agent in food products.
Onion is rich in bioactive and volatile compounds with antioxidant activity. However, the pungent odor of volatile compounds (VOCs) released restricts its use. The encapsulation of red onion extract ...by electrospinning is an alternative to mask this odor and protect its bioactive compounds. The main objective of this study was to encapsulate red onion bulb extract (ROE) in different concentrations into zein nanofibers by electrospinning and evaluate their thermal, antioxidant, and hydrophilicity properties. The major VOC in ROE was 3(2H)‐furanone, 2‐hexyl‐5‐methyl. Incorporating ROE into the polymeric solutions increased electrical conductivity and decreased apparent viscosity, rendering nanofibers with a lower average diameter. The loading capacity of ROE on fibers was high, reaching 91.5% (10% ROE). The morphology of the nanofibers was random and continuous; however, it showed beads at the highest ROE concentration (40%). The addition of ROE to the nanofibers increased their hydrophilicity. The nanofibers’ antioxidant activity against 2,2‐diphenyl‐1‐picrylhydrazyl, nitric oxide, and hydroxyl radicals ranged from 32.5% to 57.3%. The electrospun nanofibers have the potential to protect and mask VOCs. In addition, they offer a sustainable alternative to the synthetic antioxidants commonly employed in the food and packaging industry due to their antioxidant activities.
ABSTRACT Synthetic preservatives are widely present in processed foods, but most of them have carcinogenic potential, requiring the development of new natural alternatives such as fruit extracts, for ...microbial control. The objective of the study was to evaluate the chemical characterization, antioxidant, and antimicrobial activity of the sugar apple pulp (Annona squamosa L.). Physicochemical characteristics were evaluated, an extract was prepared, and its antioxidant activity by DPPH method and antimicrobial by disk diffusion. Minimal inhibitory concentration and minimum bactericidal concentration against strains of Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were evaluated. The physicochemical analysis revealed that sugar apple pulp had 75.0% moisture, 3.0% ash, 4.0% protein, 0.2% lipids, 3.3% fibers, and 14.5% carbohydrates. The antioxidant activity of the extract by the DPPH method was 20.6%. The pulp extract from the sugar apple had inhibition zone for Staphylococcus aureus, satisfactory inhibitory effect against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium, but did not present a bactericidal effect. Sugar apple pulp presents adequate levels of nutrients and potential for food application due to its microbiological activity and antioxidant properties.
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