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BACKGROUND: Essential oils (EOs) are natural substances that serve as sources of bioactive compounds with antioxidant and antimicrobial properties. OBJECTIVE: This objective is to understand intellectual property related to patent documents on EOs and nanotechnology. METHODS: The nanotechnology growth curve applied to EOs demonstrated that the period from 2015 to 2017 was the most prominent, with a peak in 2016. China is the dominant country, mainly through research developed in the academic area. RESULTS: The food industry area had the highest number of patents filed, highlighting the preservation line. Ginger essential oil, chitosan and Tween 80 were preferentially used as a core, wall material, and emulsifier, respectively. In the market, the use of EOs is more associated with the pharmaceutical/ cosmetics industry. In addition, the food industry market bets more on products based on hemp oil nanocapsules. CONCLUSION: EO nanotechnology is promising for the development of sustainable food systems. However, this nanotechnology in Brazil has not yet advanced enough in the food industry, although there are government incentives that may change this paradigm in the future. The profile of the patent documents and the products in the market differ between the application and the types of oils. In addition, there is a gap between the volume of patent documents investigated and the transfer of technology to the commercial sector, but this constitution could be better explored, given the properties of EOs.
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Óleos Voláteis , Cannabis , Análise de Dados , Nanotecnologia , Patentes como Assunto , Extratos VegetaisRESUMO
Starch derivatives are versatile compounds that are widely used in the pharmaceutical industry. This article reviews the advances in the research on hydrophilic and hydrophobic starch derivatives used to develop drug delivery systems over the last ten years, specifically microparticles, nanoparticles, nanocrystals, hydrogels, and scaffolds using these materials. The fundamentals of drug delivery systems, regulatory aspects, and chemical modifications are also discussed, along with the synthesis of starch derivatives via oxidation, etherification, acid hydrolysis, esterification, and cross-linking. The chemical modification of starch as a means to overcome the challenges in obtaining solid dosage forms is also reviewed. In particular, dialdehyde starches are potential derivatives for direct drug attachment; carboxymethyl starches are used for drug encapsulation and release, giving rise to pH-sensitive devices through electrostatic interactions; and starch nanocrystals have high potential as hydrogel fillers to improve mechanical properties and control drug release through hydrophilic interactions. Starch esterification with alginate and acidic drugs could be very useful for site-specific, controlled release. Starch cross-linking with other biopolymers such as xanthan gum is promising for obtaining novel polyelectrolyte hydrogels with improved functional properties. Surface modification of starch nanoparticles by cross-linking and esterification reactions is a potential approach to obtain novel, smart solid dosages.
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Aprovação de Drogas/organização & administração , Sistemas de Liberação de Medicamentos/métodos , Amido/química , Reagentes de Ligações Cruzadas/química , Esterificação , Legislação de Medicamentos , Estados Unidos , United States Food and Drug AdministrationRESUMO
Natural colorants from microbial fermentation have gained significant attention in the market to replace the synthetic ones. Talaromyces spp. produce yellow-orange-red colorants, appearing as a potential microorganism to be used for this purpose. In this work, the production of natural colorants by T. amestolkiae in a stirred-tank bioreactor is studied, followed by its application as additives in bio-based films. The effect of the pH-shift control strategy from 4.5 to 8.0 after 96 h of cultivation is evaluated at 500 rpm, resulting in an improvement of natural colorant production, with this increase being more significant for the orange and red ones, both close to 4-fold. Next, the fermented broth containing the colorants is applied to the preparation of cassava starch-based films in order to incorporate functional activity in biodegradable films for food packaging. The presence of fermented broth did not affect the water activity and total solids of biodegradable films as compared with the standard one. In the end, the films are used to pack butter samples (for 45 days) showing excellent results regarding antioxidant activity. It is demonstrated that the presence of natural colorants is obtained by a biotechnology process, which can provide protection against oxidative action, as well as be a functional food additive in food packing biomaterials.
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The objective of this study was to determine the best operational conditions for obtaining red propolis extract with high antioxidant potential through supercritical fluid extraction (SFE) technology, using carbon dioxide (CO2) as the supercritical fluid and ethanol as the cosolvent. The following parameters were studied: overall extraction curve, S/F (mass of CO2/mass of sample), cosolvent percentage (0, 1, 2 and 4%) and global yield isotherms as a function of different pressures (250, 350 and 450 bar) and temperatures (31.7, 40 and 50 °C). Within the investigated parameters, the best conditions found were an S/F of 131 and the use of ethanol at the highest concentration (4% w/w), which resulted in higher extract yields and higher content of antioxidant compounds. Formononetin, the main biomarker of red propolis, was the compound found at the highest amounts in the extracts. As expected, the temperature and pressure conditions also influenced the process yield, with 350 bar and 40 °C being the best conditions for obtaining bioactive compounds from a sample of red propolis. The novel results for red propolis found in this study show that it is possible to obtain extracts with high antioxidant potential using a clean technology under the defined conditions.
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Antioxidantes/química , Cromatografia com Fluido Supercrítico/métodos , Fenóis/química , Própole/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Ascomicetos/efeitos dos fármacos , Dióxido de Carbono/química , Cromatografia Líquida de Alta Pressão , Etanol/química , Flavonoides/química , Flavonoides/farmacologia , Humanos , Isoflavonas/química , Fenóis/farmacologia , Própole/isolamento & purificação , Própole/farmacologia , Solventes/químicaRESUMO
The present study aims to produce arrowroot flour fermented by kefir grains, in addition to assessing the physicochemical, nutritional, and microbiological characteristics. Fermented arrowroot flour was produced at room temperature (approximately 25 to 28 °C). Fermentation was conducted in batch (6 kg of the substrate and 10% of kefir grains were added with homogenization every 3 hr). Samples were evaluated every 12 hr for both fermentation processes (fermentation process 1: 24 hr and fermentation process 2: 48 hr). The flours were evaluated for physicochemical, nutritional, and microbiological qualities, using a completely randomized design, considering only the variation in the duration of both fermentation processes (from 24 to 48 hr). The fermentation process positively modified the physicochemical, nutritional, and microbial characteristics of the flours. An increase in antioxidant activity (IC50 : control flour [CF] = 18.9 ± 0.13; arrowroot kefir flour [24 hr of fermentation; AKF1] = 15.36 ± 0.14; and arrowroot kefir flour [48 hr of fermentation; AKF2] = 13.84 ± 0.15), protein percentage (CF = 3.08 ± 0.12; AKF1 = 4.87 ± 0.33; and AKF2 = 6.00 ± 0.07), and organic acid (lactic, acetic, and propionic acids) production was observed, as well as modification in color (browning), the conformation of starch structures, and carbohydrate reduction. These results suggested that the "arrowroot kefir flours" open a new perspective for introduction in the market as a new product that can be used as food in nature or food ingredient for making bread, biscuits, pasta, and others, showing microbiological safety and functions properties. PRACTICAL APPLICATION: The fermented flours present improved nutritional characteristics due to the fermentation process, such as higher antioxidant activity and protein levels. Regarding the population growth and societal demand for healthier food, one possibility is to provide a fermented flour with added nutritional value and raise knowledge about the arrowroot. Thus, these flours can be used in various food items or as an ingredient in food preparations for consumers that desire a healthy diet.
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Farinha/análise , Kefir/análise , Marantaceae/química , Pão/análise , Fermentação , Indústria Alimentícia , Valor Nutritivo , Amido/análiseRESUMO
The effects of the drying process using the conventional oven and freeze-drying on the thermogravimetric profile, proximate composition, color parameters, individual bioactive compounds, and antioxidant activity in the grape residue (skin) were evaluated. Twenty individual phenolic compounds were identified, where a variation in concentration was observed for flavonols, stilbenes, phenolic acids, flavonoids, procyanidins, and particularly anthocyanins (malvidin-3,5-di-O-glucoside of 253.2-536.9 mg/kg) due to the drying process. Drying in a conventional oven caused a decrease of 23% of the total polyphenols. The skin of the BRS magna grape has a high concentration of total phenolic content of 489.5-148.3 mg.GAE/100 g, total anthocyanin content of 124.9-260.1 mg.CE/100 g, and total flavonoid content of 12.7-26.0 mg.QE/100 g. The results of free radical scavenging activity (1.26-4.91 µg/mL, as EC50) and ferric reducing antioxidant power (82.93-184.10 µmol/g of skin as equivalent to Fe2SO4) indicate high antioxidant activity, independently of the drying process applied. It was concluded that, if the application is directed to anthocyanin compounds, the use of lyophilization is recommended. On the other hand, if the interest is in bioactive compounds that exert antioxidant activity, conventional oven-drying can be used.
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Antioxidantes/análise , Dessecação/métodos , Flavonoides/análise , Liofilização/métodos , Polifenóis/análise , Proantocianidinas/análise , Vitis/química , Cromatografia Líquida de Alta PressãoRESUMO
This study aimed to evaluate the biomass production of Spirulina sp. LEB 18 cultivated in wastewater from the desalination process. The outdoor cultivations (210 L) were performed using as culture medium 100% wastewater supplemented with 25% of Zarrouk constituents (Tcs). In parallel, it was performed a control assay using 100% Zarrouk constituents. The biomass production in Tcs assay (1.14 g L-1) was only 9% lower than the control assay (1.25 g L-1). The Tcs assay showed a higher content of carbohydrates (52.29%), lipids (12.79%) and ash (2.69%) compared to the control assay (47.91; 7.59 and 1.29%, respectively). The biomass from the control and Tcs assays had mostly monounsaturated fatty acids C15:1 and C18:2n6t. The Spirulina sp. LEB 18 could use efficiently the nutrients from the wastewater, showing high removal efficiency of NO3- (96.99%), PO4 (83.11%) and Z (96.43%). At the same time, high added value biomolecules were produced for different purposes.
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Microalgas , Spirulina , Biomassa , Reatores Biológicos , Carboidratos , Águas ResiduáriasRESUMO
This work aimed to use sodium trimetaphosphate/sodium tripolyphosphate cross-linked potato, banana, corn, cassava, and breadfruit starches as wall materials for C-phycocyanin encapsulation, characterize them and evaluate their in vivo pharmacological effects in an inflammation model. The cross-linked starches were successfully obtained, characterized, and submitted to C-phycocyanin encapsulation by freeze-drying. The characterization of cross-linked starches-C-phycocyanin composites by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetry, and differential scanning calorimetry demonstrated that the C-phycocyanin was encapsulated between amorphous chains of cross-linked starches. Among the five preparations, the cross-linked potato starch presented the highest phosphorous content (0.084%), substitution degree (0.004), water uptake capacity (0.88 g g-1), and C-phycocyanin encapsulation efficiency (67.58%), thus was tested in vivo. The cross-linked potato starch-C-phycocyanin prolonged the antihyperalgesic effects attributed to C-phycocyanin, evaluated by complete Freund's adjuvant (CFA) model. Starch cross-linking promoted the formation of a hydrogel network in swollen state entrapping C-phycocyanin, thus, acting as a barrier to its release to the medium and promoting long-lasting in vivo effects. The combination of chemical modification of starches followed by physical treatment presented itself as a useful tool for the development of pharmaceutical formulations.
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Materiais Revestidos Biocompatíveis/química , Reagentes de Ligações Cruzadas/química , Compostos Organofosforados/química , Ficocianina/química , Amido/química , Ácidos Esteáricos/química , Varredura Diferencial de Calorimetria , Cromatografia Líquida de Alta Pressão , Óleos/química , Fósforo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Água/química , Difração de Raios XRESUMO
Beer has been one of the most consumed alcoholic beverages worldwide. However, the incorporation of adjuncts in the beer can add new organoleptic and functional characteristics to the beverage. For this, Beauregard sweet potato shows high potential due to being a rich source of starch and many bioactive compounds. The aim of this study was to develop the best process condition to produce a Sweet potato beer with enhanced nutritional and antioxidant properties and good sensory characteristics. Beer samples showed increased antioxidant activity especially due to ß-carotene and their total phenolic content. The phytochemical profile of sweet potato biocompounds demonstrated a direct effect of this adjunct on sensory and functional characteristics of the finished beer. In conclusion, it was found that Beauregard sweet potato is a promising adjunct for beer brewing with nutraceutical properties due to its rich composition of bioactive compounds.
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Cerveja/análise , Ipomoea batatas/química , Antioxidantes/análise , Fenômenos Químicos , Fenóis/análise , Amido/química , beta Caroteno/análiseRESUMO
The composition of brackish groundwater from Brazilian backlands contains important elements necessary for metabolism in microalgae. This study evaluated the use of 100% brackish groundwater with different amounts of Zarrouk nutrients for Spirulina sp. LEB 18 cultivation. The growth parameters and biomass composition, including the concentrations of proteins, carbohydrates, ash, lipids, and fatty acids, were evaluated. The best growth parameter results were obtained in the assay using 100% brackish groundwater and only 25% of Zarrouk nutrients, which were equal to those obtained for the control culture. The concentrations of carbohydrates and polyunsaturated fatty acids were increased by as much as 4- and 3.3-fold, respectively, when brackish groundwater was used in the cultures. The lipid profile demonstrated that the biomass had the potential for use in biodiesel production. The use of brackish groundwater is a sustainable, economical way to obtain high-quality biomass for different applications during Spirulina sp. LEB 18 cultivation.
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Metabolismo dos Carboidratos , Ácidos Graxos Insaturados/biossíntese , Água Subterrânea , Spirulina/metabolismo , Proteínas de Bactérias/metabolismo , Biomassa , Brasil , Spirulina/genéticaRESUMO
Propolis is a complex mixture of resinous and balsamic material collected from the exudates of plants, shoots, and leaves by bees. This study evaluated red propolis extracts obtained by conventional (ethanolic) extraction and ultrasound-assisted extraction of six samples from different regions of northeastern Brazil. The total phenolic compounds and flavonoids, in vitro antioxidant activity, concentration of formononetin and kaempferol and the cytotoxicity against four human tumor cell lines were determined for all twelve obtained extracts. Significant variations in the levels of the investigated compounds were identified in the red propolis extracts, confirming that the chemical composition varied according to the sampling region. The extraction method used also influenced the resulting propolis compounds. The highest concentration of the compounds of interest and the highest in vitro antioxidant activity were exhibited by the extracts obtained from samples from state of Alagoas. Formononetin and kaempferol were identified in all samples. The highest formononetin concentrations were identified in extracts obtained by ultrasound, thus indicating a greater selectivity for the extraction of this compound by this method. Regarding cytotoxic activity, for the HCT-116 line, all of the extracts showed an inhibition of greater than 90%, whereas for the HL-60 and PC3 lines, the minimum identified was 80%. In general, there was no significant difference (p>0.05) in the antiproliferative potential when comparing the extraction methods. The results showed that the composition of Brazilian red propolis varies significantly depending on the geographical origin and that the method used influences the resulting compounds that are present in propolis. However, regardless of the geographical origin and the extraction method used, all the red propolis samples studied presented great biological potential and high antioxidant activity. Furthermore, the ultrasound-assisted method can be efficiently applied to obtain extracts of red propolis more quickly and with high concentration of biomarkers of interest.
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Antioxidantes/farmacologia , Flavonoides/química , Isoflavonas/farmacologia , Quempferóis/farmacologia , Própole/química , Antioxidantes/química , Brasil , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Células HCT116 , Células HL-60 , Humanos , Isoflavonas/química , Quempferóis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , EspectrofotometriaRESUMO
In this study, we evaluated the effects of the storage time on the physicochemical properties, bioactive compound content, and antioxidant capacity of jam prepared from grape peel extract to explore its potential as a supplementary food and/or functional ingredient. The ethanolic extract from Syrah var. grape peel exhibited high bioactive compound concentrations and antioxidant activity. The jam stability (prepared with 8.9% of extract) at 14°C was evaluated at 0, 15, 30, 45, and 60 days. The jam was found to contain high concentrations of polyphenolic compounds (137.0 ± 3.2 mg of gallic acid equivalent/100 g), total flavonoids (128.5 ± 23.0 mg of equivalent/100 g), and total anthocyanins (92.5 ± 4.0 mg of cyanidin equivalent/100 g). However, a large reduction in the flavonoid (70%-90%), anthocyanin (29%-35%), and phenolic (23%-30%) content was observed during storage. The free radical-scavenging activity (DPPH-), ferric reducing antioxidant power (FRAP), and ß-carotene-linoleic acid assays revealed the great antioxidant potential of the jam prepared from grape peel extract, which exhibited significant levels of radical-neutralizing activity, especially as determined by the DPPH method with EC50 values ranging from 2.3 ± 0.1 to 3.9 ± 0.1 µg/ml. High R 2 values (p > 0.90) were obtained for the correlation between the DPPH results and the concentrations of the compounds of interest. In summary, the high bioactive compound contents and antioxidant capacity of the jam produced from grape peel suggest that it may provide health benefits as a source of natural antioxidants upon incorporation to several food industry products.
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Interest in nanocellulose obtained from natural resources has grown, mainly due to the characteristics that these materials provide when incorporated in biodegradable films as an alternative for the improvement of the properties of nanocomposites. The main purpose of this work was to investigate the effect of the incorporation of nanocellulose obtained from different fibers (corncob, corn husk, coconut shell, and wheat bran) into the chitosan/glycerol films. The nanocellulose were obtained through acid hydrolysis. The properties of the different nanobiocomposites were comparatively evaluated, including their barrier and mechanical properties. The nanocrystals obtained for coconut shell (CS), corn husk (CH), and corncob (CC) presented a length / diameter ratio of 40.18, 40.86, and 32.19, respectively. Wheat bran (WB) was not considered an interesting source of nanocrystals, which may be justified due to the low percentage of cellulose. Significant differences were observed in the properties of the films studied. The water activity varied from 0.601 (WB Film) to 0.658 (CH Film) and the moisture content from 15.13 (CS Film) to 20.86 (WB Film). The highest values for tensile strength were presented for CC (11.43 MPa) and CS (11.38 MPa) films, and this propriety was significantly increased by nanocellulose addition. The results showed that the source of the nanocrystal determined the properties of the chitosan/glycerol films.
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The objective was to evaluate the effect of reusing Zarrouk's medium on a Spirulina sp. LEB 18 culture by determining kinetic parameters, chemical composition, biofuels, and thermal characterization. Cultivation was performed in a raceway bioreactor for 7â¯days, the supernatant was reused for four cycles. Culturing the microalga in the reused medium resulted in a cellular yield of 2.30â¯g L-1 (control) and 2.04, 1.89, 1.73, and 1.15â¯g L-1 for four cycles with no influence on cell growth and productivity. Biomass with high contents of carbohydrates (58.00%, 3rd cycle), phycocyanin (2.47â¯mgâ¯mL-1, 1st cycle), and saturated fatty acids (60.13%, 4th cycle) were obtained with an increase in the profiles of C16:0 (45.85%) and C18:2n6 (47.40%) in the 1st cycle. The reuse of Zarrouk's medium allowed obtaining biomass with reduced cost and differentiated characteristics, allowing the exploration of commercially important biomolecules by the completion of up to four cycles.
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Reatores Biológicos , Spirulina/metabolismo , Biocombustíveis , Biomassa , Metabolismo dos Carboidratos , Carboidratos , Ficocianina/metabolismoRESUMO
Analytical techniques such HPSEC, DSC, and TGA have been employed for amylose determination in starch samples, though spectrophotometry by iodine binding is most commonly used. The vast majority of these techniques require an analytical curve, using amylose and amylopectin standards with physicochemical properties similar to those found in the original starch. The current study aimed to obtain the amylose and amylopectin fractions from potato, banana, corn, and cassava starches, characterize them, and evaluate their behavior via thermogravimetric curves. Blue amylose iodine complex and HPSEC-DRI methods have obtained high purity amylose and amylopectin fractions. All molecular weights of the obtained amylose and amylopectin fractions were similar to those presented in other reports. Different results were obtained by deconvolution of the amylopectin polymodal distribution. All amyloses presented as semi-crystalline V-type polymorphs, while all amylopectin fractions were amorphous. The Tg of all Vamyloses presented were directly proportional to their respective crystalline index. TGA evaluations have shown that selective precipitation of amylose with 1-butanol strongly changes its thermal behavior. Therefore, the separation procedure used was an ineffective pathway for obtaining standards for thermal studies.
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Amilopectina/química , Amilose/química , Manihot/química , Musa/química , Solanum tuberosum/química , Zea mays/química , Amilopectina/isolamento & purificação , Amilose/isolamento & purificaçãoRESUMO
Polyhydroxyalkanoates (PHA) are biopolymers synthesized by different microorganisms and considered substitute powers for petroleum-based plastics because they have similar mechanical properties as synthetic polymers, can be processed in a similar way and are fully biodegradable. Currently commercial PHAs are produced in fermenters using bacteria and large amounts of organic carbon sources and salts in the culture media, accounting for approximately 50% of the total production costs. A greater commercial application of the PHA is limited to a decrease in the cost of production. Several studies suggest that microalgae are a type of microorganisms that can be used to obtain PHAs at a lower cost because they have minimum nutrient requirements for growth and are photoautotrophic in nature, i.e. they use light and CO2 as their main sources of energy. Thus, this work aims to provide a review on the production of PHAs of different microalgae, focusing on the properties and composition of biopolymers, verifying the potential of using these bioplastics instead of petroleum based plastics. Studies of stimulation PHA synthesis by microalgae are still considered incipient. Still, it is clear that microalgae have the potential to produce biopolymers with lower cost and can play a vital role in the environment.
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Microalgas/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Biopolímeros/química , Biopolímeros/metabolismo , Vias Biossintéticas , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/isolamento & purificaçãoRESUMO
Researches about light emitting diodes (LEDs) as energy source in microalgae cultivations has been growing in recent years due to its spectral quality, durability and reduced energy consumption. In this study, green, red and yellow LEDs were evaluated as energy source in Synechococcus nidulans LEB 115 cultures. Productivities and specific growth rates were up to 2.5 times greater than in cultures using fluorescent light. The different LED colors evaluated did not influence the chlorophyll, carotenoid or lipid productions. Biomass cultivated with LEDs showed high amounts of saturated fatty acids (above 48%), which is desirable for biodiesel production. In addition to the Synechococcus nidulans LEB 115 growth stimulation, the application of green, red and yellow LEDs in the cultivations produces potential biomass for biodiesel synthesis and other industrial interest biomolecules utilization.
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Carotenoides/biossíntese , Clorofila/biossíntese , Lipídeos/análise , Synechococcus/metabolismo , Biocombustíveis , Biomassa , Cor , Luz , Lipídeos/biossíntese , Microalgas/metabolismo , Pigmentação , Synechococcus/crescimento & desenvolvimentoRESUMO
The nanoencapsulation of carotenoids is presented as a positive alternative to broaden the application of these pigments in the food industry. In this study, we investigated the use of yellow passion fruit albedo flour as an encapsulating material for the production of nanodispersions of carotenoid extract obtained from Spirulina sp. LEB 18. Nanodispersions were characterized for their physicochemical properties, antioxidant activity, stability, and retention of carotenoids after 60â¯days of storage (4⯰C). The nanodispersions made from yellow passion fruit albedo flour and microalgae carotenoid extract presented an average particle diameter at the nanometer scale, high antioxidant activity, and carotenoid retention compared to nanodispersions containing synthetic ß-carotene. Yellow passion fruit albedo flour as a polymeric material in the production of carotenoid nanodispersions is an alternative to commercial polymers and allows greater stability and broader application of these pigments.
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Carotenoides/química , Nanoestruturas/química , Passiflora/química , Spirulina/química , Antioxidantes/química , Antioxidantes/farmacologia , Farinha , Armazenamento de Alimentos , Frutas/química , Extratos Vegetais/química , beta Caroteno/análiseRESUMO
Bacteria that are capable of accumulating lipids in their cells as storage compounds can also produce polyhydroxyalkanoates of high technological value, depending on the specific culture conditions. The objective of this study was to utilize crude glycerol from biodiesel (CGB) as a substrate, which is a major byproduct from biodiesel production, to produce lipophilic compounds. Bacillus megaterium INCQS 425 was cultivated and evaluated for the production of lipophilic compounds and the properties of these compounds were investigated. Cultivation of the bacteria in a medium with a C:N ratio of 0.60:1 favored the accumulation of lipids by (17.5%) comprising mainly palmitic acid (13.08%), palmitoleic (39.48%), and especially oleic acid (37.02%), which imparts good characteristics to biodiesel. Meanwhile, cultivation of the bacteria in a medium with a C:N ratio of 4:1 favored the accumulation of polyhydroxyalkanoates (PHA) (3.31gL-1) mainly comprising medium and long chain PHA. Low crystallinity (<30%) and excellent thermal properties make them suitable for processes that demand high temperatures, such as extrusion. The lipids produced in the present study had satisfactory oxidative stability for the production of quality biodiesel. The polyhydroxyalkanoates produced in the study are of low cost and have promising thermal properties that justify its technological potential, thereby configuring highly competitive bioproducts.
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Glicerol/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Bacillus megaterium/metabolismo , Biocombustíveis , Biotecnologia , Ácidos Graxos/metabolismo , Peso Molecular , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/metabolismoRESUMO
This objective of this work was to monitor the EPS production during the growth of Spirulina sp. LEB-18, evaluate the productivity and to characterize the exopolymers obtained on pilot-scale under outdoor conditions. The production of crude EPS occurred in all phases of biomass growth and was approximately ten folds higher than that biomass concentration of Spirulina sp. LEB-18 at the end cultivation, demonstrating the importance of the use of supernatant after harvesting of Spirulina to obtain high value bioproducts. The EPS extracted by Spirulina sp. LEB-18 are typically heteropolymers with one high molecular weight fraction (polysaccharides) with potential to be utilized as an alternative bioflocculant and another fraction of lower molecular mass (proteins). The presence of uronic acids, pyruvates and acyl groups of carbohydrates or carboxylic groups of amino acids in protein moiety is the main responsible for overall negative charge of EPS, which is also of biotechnological importance. Moreover, due to the pseudoplastic behavior of the solutions and high thermal stability, the obtained EPS can be widely applied in several industrial sectors, thus determining its technological and market potentiality.