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1.
Nutr Metab Cardiovasc Dis ; 32(1): 279-289, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34893407

RESUMO

BACKGROUND AND AIMS: High-fat diet (HFD) intake during gestation and lactation has been associated with an increased risk of developing cardiometabolic disorders in adult offspring. We investigated whether metabolic alterations resulting from the maternal consumption of HFD are prevented by the addition of omega-3 (É·3) in the diet. METHODS AND RESULTS: Wistar rat dams were fed a control (C: 19% of lipids and É·6:É·3 = 12), HF (HF: 33% lipids and É·6:É·3 = 21), or HF enriched with É·3 (HFω3: 33% lipids and É·6:É·3 = 9) diet during gestation and lactation, and their offspring food consumption, murinometric measurements, serum levels of metabolic markers, insulin and pyruvate sensitivity tests were evaluated. The maternal HFD increased body weight at birth, dyslipidemia, and elevated fasting glucose levels in the HF group. The enrichment of É·3 in the maternal HFD led to lower birth weight and improved lipid, glycemic, and transaminase biochemical profile of the HFω3 group until the beginning of adulthood. However, at later adulthood of the offspring, there was no improvement in these biochemical parameters. CONCLUSION: Our findings show the maternal consumption of high-fat É·3-rich diet is able to attenuate or prevent metabolic disruption elicited by HFD in offspring until 90 days old, but not in the long term, as observed at 300 days old of the offspring.


Assuntos
Ácidos Graxos Ômega-3 , Efeitos Tardios da Exposição Pré-Natal , Animais , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos , Feminino , Humanos , Lactação , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Ratos , Ratos Wistar
2.
Artigo em Inglês | MEDLINE | ID: mdl-34659431

RESUMO

In the present study, the antifungal activity and toxicity of the geranyl cinnamate ester (GCE) were investigated. The GCE showed antifungal activity at a minimum concentration of 0.16 µL/mL against Candida albicans and at concentrations greater than 2.5 µL/mL against Aspergillus niger. In acute toxicity studies, the administration of GCE (2.000 mg/kg) affected the body weight gain and food intake but did not induce the mortality of the animals studied. After the investigation of repeated-dose toxicity of GCE at 2 and 4 mg/kg, the hematological and biochemical parameters were changed. In addition, the adrenal weight of male mice treated with GCE at 4 mg/kg was affected. In conclusion, according to the Organization for Economic Cooperation and Development (OECD) acute toxicity parameters, the geranyl cinnamate ester can be classified into safety category number 5. The results of this study suggested that the geranyl cinnamate ester may be a source of natural antifungals.

3.
Food Res Int ; 149: 110706, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600698

RESUMO

Banana peel is a source of polysaccharides: pectin, hemicellulose and cellulose. Recent studies have shown that these carbohydrate fractions can be converted into oligomers, which have applications in food, feed and pharmaceuticals, claiming important technical, functional and biological activities. Potential prebiotic activity of pectin and cellulose oligosaccharides obtained from banana peel was already reported. Based on technologies developed for fractionation and extraction of polysaccharides, such as pectin, hemicellulose and cellulose, banana peel can be explored to obtain functional oligosaccharides.


Assuntos
Musa , Oligossacarídeos , Pectinas , Polissacarídeos , Prebióticos
4.
J Bodyw Mov Ther ; 25: 53-60, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33714511

RESUMO

BACKGROUND: Stroke is the leading cause of long-term disability in adults, causing residual sensorimotor deficits in many survivors. Patients may have different impairments according to laterality of injury, as well as different responses to some therapies. OBJECTIVE: This preliminary study sought to investigate motor learning in rehabilitation of stroke patients with non-immersive virtual environment by process (electroencephalography) and product (performance) measures in stroke patients with left and right cerebral hemispheres damage. METHODS: The study included 10 chronic stroke patients; 5 with left brain injury (LI), mean age 48.8 years (±4.76), and 5 with right brain injury (RI), mean age 52 years (±10.93). Patients were evaluated for electroencephalographic activity (alpha and beta frequencies) and performance (absolute error) in a darts game on XBOX Kinect (Microsoft®). Then they underwent a virtual darts game training task, 12 sessions for 4 weeks (acquisition stage). After training, they were revaluated (long-term retention). RESULTS: RI group increased alpha power and decreased beta in ipsilesional areas, increased activation on left hemisphere and decreased the absolute error of performance; LI group increased right hemisphere activation and did not decrease the absolute error. CONCLUSIONS: Patients with right brain injury reduce neural effort and errors after virtual darts training, which did not happen to patients with left brain injury. Therefore, the laterality of lesion should be considered in studies that use virtual reality for stroke rehabilitation.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Realidade Virtual , Adulto , Eletroencefalografia , Lateralidade Funcional , Humanos , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações
5.
World J Microbiol Biotechnol ; 37(2): 21, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33428050

RESUMO

Biosurfactants can be widely used in industries as pharmaceutical agents, for microbial enhanced oil recovery, crop biostimulation, among others. Surfactin and rhamnolipids are well-known biosurfactants. These compounds have several advantages over chemical surfactants, however they are not economically competitive, since their production cost is up to 12 times higher than chemical surfactants. In this sense, an interesting approach is to replace synthetic culture medium, which represents ≈ 30% of the production cost by agro-industrial wastes. In addition, biosurfactant productivity can be easily enhanced by inductor supplementation into culture medium that triggers biosurfactant metabolism. Biosurfactant inducers are mainly a pool of hydrophobic molecules (e.g. olive oil-saturated and unsaturated fatty acids, proteins and vitamins). Nevertheless, there is little information on inducer effects of specific molecules (e.g. oleic acid). In general, hydrophobic inducers lead to higher fatty acid chain lengths (biosurfactant chemical structure). Therefore, the aim of this review was to critically discuss the current state of the art and future trends on biosurfactant production, in particular biosurfactant inducers. Taking into account the last 10 years, there is a clear lack of information on correlation between "inducers" or "hydrophobic inducers" AND "biosurfactants", since only 13 documents were found (Scopus database). Thus, it is essential to deeply investigate all inducer effects on biosurfactant production, mainly yield and chemical structure.


Assuntos
Glicolipídeos/química , Glicolipídeos/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Meios de Cultura , Ácidos Graxos , Interações Hidrofóbicas e Hidrofílicas , Resíduos Industriais , Lipopeptídeos
6.
Nat Prod Res ; 35(24): 5981-5987, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32840398

RESUMO

The chemical composition and biological properties of citronella essential oil were modified by enzymatic esterification reaction of the major monoterpenic alcohols with cinnamic acid. The almost complete conversion of geraniol and citronellol present in the citronella (Cymbopogon winterianus) essential oil, into geranyl (99%) and citronellyl (98%) cinnamates was obtained after 48 hours of reaction using a molar ratio of 3:1 (cinnamic acid/alcohol), lipase concentration (Novozym 435) of 15% (w/w) and 70 °C. The esterified oil showed higher antimicrobial activity against Staphylococcus aureus bacteria resistant to oxacillin and penicillin and also greater larvicidal activity against Aedes aegypti larvae compared to unesterified oil. The results concerning the evaluation of toxicity against Artemia salina and cytotoxicity against monkey kidney epithelial cells also showed the superiority of the esterified oil.


Assuntos
Cymbopogon , Óleos Voláteis , Monoterpenos Acíclicos , Animais , Esterificação , Óleos de Plantas
7.
Bioprocess Biosyst Eng ; 44(2): 297-306, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32948889

RESUMO

The deconstruction of banana peel for carbohydrate recovery was performed by sequential treatment (acid, alkaline, and enzymatic). The pretreatment with citric acid promoted the extraction of pectin, resulting in a yield of 8%. In addition, xylose and XOS, 348.5 and 17.3 mg/g xylan, respectively, were also quantified in acidic liquor as a result of partial depolymerization of hemicellulose. The spent solid was pretreated with alkaline solution (NaOH or KOH) for delignification and release of residual carbohydrates from the hemicellulose. The yields of xylose and arabinose (225.2 and 174.0 mg/g hemicellulose) were approximately 40% higher in the pretreatment with KOH, while pretreatment with NaOH promoted higher delignification (67%), XOS yield (32.6 mg/g xylan), and preservation of cellulosic fraction. Finally, the spent alkaline solid, rich in cellulose (76%), was treated enzymatically to release glucose, reaching the final concentration of 28.2 g/L. The mass balance showed that through sequential treatment, 9.9 g of xylose, 0.5 g of XOS, and 8.2 g of glucose were obtained from 100 g of raw banana peels, representing 65.8% and 46.5% conversion of hemicellulose and cellulose, respectively. The study of the fractionation of carbohydrates in banana peel proved to be a useful tool for valorization, mainly of the hemicellulose fraction for the production of XOS and xylose with high value applications in the food industry.


Assuntos
Arabinose/química , Frutas/química , Musa/química , Pectinas/química , Polissacarídeos/química , Xilose/química , Hidrólise , Hidróxidos/química , Compostos de Potássio/química , Hidróxido de Sódio/química
8.
Environ Technol ; 41(20): 2648-2656, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30712503

RESUMO

The adsorption of annatto dye was analysed using kaolin clay as the adsorbent. In this work, the influence of the adsorbent particle size, agitation (0 and 100 rpm), temperature (25, 40, and 60°C), and salt presence (sodium chloride and sodium sulphate at 1, 2 and 3 wt%) on the adsorption process was studied. The adsorption increased 14.21% for particles smaller than 45 µm and the agitation (100 rpm) led to an increase of 22.41% compared to the system without agitation. The ΔG° (237.711 kJmol-1) indicated that the adsorption process was spontaneous. The negative value of ΔS° (-408.999 Jmol-1K-1) and ΔH° (-115.829 kJmol-1) showed an exothermic physisorption process. The adsorption kinetics follows the pseudo-second-order model. In the adsorption equilibrium, the tested models provided good correlation coefficients ranging from 0.744 to 0.999 with the best fit observed for the Langmuir model. The maximum adsorption capacity of the kaolin clay for the annatto dye was obtained at 25°C with 1% of sodium sulphate (q max = 59.88 mgg-1).


Assuntos
Caulim , Poluentes Químicos da Água , Adsorção , Bixaceae , Carotenoides , Concentração de Íons de Hidrogênio , Cinética , Extratos Vegetais , Temperatura , Termodinâmica
9.
J Ethnopharmacol ; 236: 21-30, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-30802613

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Popular medicine use stems of Philodendron bipinnatifidum (Araceae) in inflammation cases, such as in erysipelas, as well as orchitis and rheumatism treatment. The present study, conducted for the first time in literature, investigate the antinociceptive and anti-inflammatory activities of P. bipinnatifidum stems ethyl acetate extract (EPB). MATERIALS AND METHODS: GC/MS and HPLC analysis were performed for EPB extract. We used EPB at 250, 375 and 500 mg/kg (oral route, p.o.) in male Swiss mice. The antinociceptive activity of the plant extract assessed by acetic acid induced writhing and formalin tests. To investigate the possible participation of opioid system in EPB-mediated effects, we previously administered naloxone to the mice. Anti-inflammatory activity was evaluated using carrageenan-induced paw oedema. The open-field test aimed to investigate the possible EPB effects on the locomotor and exploratory activities. To assess the protective role of EPB on carrageenan-induced oxidative stress, the levels of NPSH, TBARS, as well as SOD and CAT activities were evaluated in blood and paw tissue. The acute toxicity of the EPB was investigated using OECD 423 guideline. RESULTS: The EPB chemical analysis by GC/MS and HPLC revealed the presence of flavonoids (luteolin and quercetin) and phytosterols (ß-sitosterol and stigmasterol). The oral treatment with the EPB inhibited mice abdominal writhings (P < 0.01) at 375 and 500 mg/kg, and reduced the formalin effect at the first-phase (500 mg/kg, P < 0.05) and also at the second-phase (500 mg/kg, P < 0.001) of the test. EPB (375 and 500 mg/kg) did not alter spontaneous locomotion in open field test, however the number of fecal bolus was significantly lower for the EPB group at 500 mg/kg when compared to the vehicle group (P < 0.05). The pretreatment with naloxone caused significant inhibition of antinociceptive activity induced by EPB in the formalin test, revealing the possible involvement of opioid receptors. EPB extract administered at 500 mg/kg (p.o.) prevented carrageenan-induced paw oedema (P < 0.05 and 0.01) until 6 h after carragenan injection. Evaluation of TBARS and NPSH levels, SOD and CAT activities in the blood and paw tissue of animals submitted to the carrageenan assay suggested that the anti-inflammatory effect of EPB may be linked to oxidative stress inhibition. The acute administration of the EPB (2000 mg/kg, p.o.) caused no mortality, demonstrating low toxicity. CONCLUSIONS: The extract of P. bipinnatifidum displays antinociceptive and anti-inflammatory activities, causing no toxicological effects. The pharmacological activity of this vegetal species may be related to the presence of flavonoids and phytosterols. Our results support the ethnomedical use of this vegetal species as analgesic and anti-inflammatory agent.


Assuntos
Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Dor/tratamento farmacológico , Philodendron/química , Extratos Vegetais/uso terapêutico , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/isolamento & purificação , Edema/induzido quimicamente , Edema/tratamento farmacológico , Inflamação , Masculino , Camundongos , Dor/induzido quimicamente , Fitoterapia , Extratos Vegetais/isolamento & purificação
10.
Compr Rev Food Sci Food Saf ; 18(4): 883-909, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33336991

RESUMO

Morinda citrifolia commonly known as noni is a perennial plant originating in Southeast Asia, consumed over 2000 years. Due to its versatility of adaptation and use of the structures of the plant for different therapeutic purposes, noni attracted the attention of researchers from the pharmaceutical and food industry. Chemical and nutritional analyzes already performed in M. citrifolia reveal the existence of more than 200 phytochemical substances with bioactive properties such as acids, alcohols, phenols, saccharides, anthraquinones, carotenoids, esters, triterpenoids, flavonoids, glycosides, lactones, iridoids, ketones, lactones, lignans, nucleosides, triterpenides, sterols, and aromatic compounds. The high nutritional value of M. citrifolia may induce therapeutic effects, including antimicrobial and antioxidant properties. The main industrial products from this plant are beverages (juice drinks), powders (from dried fruits), oil (from seeds), and leaf powders. Biological and phytotherapeutic applications of M. citrifolia are promising, but more extensive studies are still required. Thus, this review aims to gather updated and comprehensive information on Morinda citrifolia, discussing its traditional use, biochemical, phytotherapics, and toxicological properties, as well as the recent advances in the processing and standardization of products derived from noni fruit.

11.
Appl Biochem Biotechnol ; 185(3): 705-716, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29297136

RESUMO

The performance of two new commercial low-cost lipases Eversa® Transform and Eversa® Transform 2.0 immobilized in different supports was investigated. The two lipases were adsorbed on four different hydrophobic supports. Interesting results were obtained for both lipases and for the four supports. However, the most active derivative was prepared by immobilization of Eversa® Transform 2.0 on Sepabeads C-18. Ninety-nine percent of fatty acid ethyl ester was obtained, in 3 h at 40 °C, by using hexane as solvent, a molar ratio of 4:1 (ethanol/oil), and 10 wt% of immobilized biocatalyst. The final reaction mixture contained traces of monoacylglycerols but was completely free of diacylglycerols. After four reaction cycles, the immobilized biocatalyst preserved 75% of activity. Both lipases immobilized in Sepabeads C-18 were very active with ethanol and methanol as acceptors, but they were much more stable in the presence of ethanol.


Assuntos
Enzimas Imobilizadas/química , Etanol/química , Ácidos Graxos/biossíntese , Lipase/química , Óleo de Girassol/química , Biocatálise , Cromatografia Líquida de Alta Pressão , Diglicerídeos/análise , Esterificação , Ésteres , Hexanos/química , Interações Hidrofóbicas e Hidrofílicas , Monoglicerídeos/análise , Polímeros/química
12.
Bioprocess Biosyst Eng ; 38(9): 1739-48, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26037641

RESUMO

With the aim of studying the best method for the interaction of polyurethane (PU) foam and Candida antarctica lipase B, different methods of CalB immobilization were studied: adsorption (PU-ADS), bond (using polyethyleneimine) (PU-PEI), ionic adsorption by PEI with cross-linking with glutaraldehyde (PU-PEI-GA) and entrapment (PU). The characterization of immobilized enzyme derivatives was performed by apparent density and Fourier transform infrared spectroscopy. The free enzyme and enzyme preparations were evaluated at different pH values and temperatures. The highest enzyme activity was obtained using the PU method (5.52 U/g). The methods that stood out to compare the stabilities and kinetic parameters were the PU and PU-ADS. Conversions of 83.5 and 95.9 % for PU and PU-ADS derivatives were obtained, in 24 h reaction, using citronella oil and propionic acid as substrates.


Assuntos
Aromatizantes/síntese química , Proteínas Fúngicas/química , Lipase/química , Óleos de Plantas/química , Poliuretanos/química , Propionatos/síntese química , Adsorção , Reagentes de Ligações Cruzadas/química , Ativação Enzimática , Estabilidade Enzimática , Enzimas Imobilizadas/química , Gases/química , Concentração de Íons de Hidrogênio , Propionatos/química , Especificidade por Substrato , Temperatura
13.
Bioprocess Biosyst Eng ; 38(8): 1569-77, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25894295

RESUMO

The hybrid alginate/gelatin/calcium oxalate (AGOCa) support was successfully synthesized through the biomimetic mineralization method for immobilization in situ of a pectinolytic extract from Aspergillus niger ATCC 9642 via entrapment technique. The efficiency of immobilization reached 72.7%. Sodium oxalate buffer (100 mM, pH 5.5) was selected as adjuvant of the immobilization process by allowing the formation of a calcified shell around the calcium alginate capsule, significantly increasing the stability to storage, thermal and recycling of the enzymatic immobilized pectinolytic extract. The pH and temperature for maximum activity were from 5.0 to 6.0 and 60 to 80 °C, respectively. The new hybrid support can be a potential alternative to obtain immobilized pectinases with properties for advantageous industrial applications.


Assuntos
Alginatos/química , Aspergillus niger/enzimologia , Materiais Biomiméticos/síntese química , Oxalato de Cálcio/química , Proteínas Fúngicas/química , Gelatina/química , Poligalacturonase/química , Materiais Biomiméticos/química , Enzimas Imobilizadas/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química
14.
Appl Biochem Biotechnol ; 176(3): 850-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25875788

RESUMO

This work shows new and promising experimental data of soybean oil and canola oil glycerolysis using Novozym 435 enzyme as catalyst in a solvent-free system using ultrasound bath for the emulsifier, monoglyceride (MAG), and diacylglycerol (DAG) production. The experiments were conducted in batch mode to study the influence of process variables as temperature (40 to 70 °C), immobilized enzyme content (2.5 to 10 wt%, relative to substrates), molar ratio glycerol/oil (0.8:1 to 3:1), agitation (0 to 1200 rpm) and ultrasound intensity (0 to 132 W cm(-2)). Highest yields of DAG+MAG (75 wt%) were obtained with molar ratio glycerol/canola oil 0.8:1, 70 °C, 900 rpm, 120 min of reaction time, 10 wt% of enzyme concentration, and 52.8 W cm(-2) of ultrasound intensity. When soybean oil was used, the best results in terms of DAG+MAGs (65 wt%) were using molar ratio of glycerol/soybean oil 0.8:1, 70 °C, 900 rpm, 90 min of reaction time, 10 wt% of enzyme content, and 40 % of ultrasound intensity (52.8 W cm(-2)). The results showed that the lipase-catalyzed glycerolysis in a solvent-free system with ultrasound bath can be a potential route for high content production of DAGs and MAGs.


Assuntos
Biocatálise , Ácidos Graxos Monoinsaturados/química , Glicerol/química , Lipase/metabolismo , Solventes/química , Óleo de Soja/química , Ondas Ultrassônicas , Candida/enzimologia , Diglicerídeos/química , Emulsificantes/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Alimentos , Proteínas Fúngicas , Cinética , Lipase/química , Monoglicerídeos/química , Óleo de Brassica napus
15.
Bioprocess Biosyst Eng ; 38(3): 437-48, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25362889

RESUMO

This work reports the transesterification of soybean oil with ethanol using a commercial immobilized lipase, Novozym 435, under the influence of ultrasound irradiation, in a solvent-free s. The experiments were performed in an ultrasonic water bath, following a sequence of experimental designs to evaluate the effects of temperature, enzyme and water concentrations, oil to ethanol molar ratio and output irradiation power on the reaction yield. Besides, a kinetic study varying the substrates molar ratio and enzyme concentration was also carried out. Results show that ultrasound-assisted lipase-catalyzed transesterification of soybean oil with ethanol in solvent-free system might be a potential alternative route to conventional alkali-catalyzed and/or traditional enzymatic methods, as high reaction yields (~78 wt%) were obtained at mild irradiation power supply (~132 W), and temperature (63 °C) in a relatively short reaction time, 1 h. Additionally, a study regarding the enzyme reuse was carried out at the experimental condition that afforded the best reaction yield.


Assuntos
Biocombustíveis , Lipase/química , Som , Óleo de Soja/química , Catálise , Enzimas Imobilizadas , Proteínas Fúngicas
16.
Ultrason Sonochem ; 19(3): 452-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22182652

RESUMO

This work reports the transesterification of soybean oil with ethanol using two commercial immobilized lipases under the influence of ultrasound irradiation. The experiments were performed in an ultrasonic water bath, following a sequence of experimental designs to assess the effects of temperature, enzyme and water concentrations, oil to ethanol molar ratio and output irradiation power on the reaction yield. Results show that ultrasound-assisted lipase-catalyzed transesterification of soybean oil with ethanol might be a potential alternative route to conventional alkali-catalyzed method, as high reaction yields (~90 wt.%) were obtained at mild irradiation power supply (~100 W), and temperature (60 °C) in a relatively short reaction time, 4h, using Lipozyme RM IM as catalyst. The repeated use of the catalyst under the optimum experimental condition resulted in a decay in both enzyme activity and product conversion after two cycles. The use of Novozym 435 led to lower conversions (about 57%) but the enzyme activity was stable after eight cycles of use, showing, however, a reduction in product conversion after the forth cycle.


Assuntos
Lipase/química , Lipase/efeitos da radiação , Compostos Orgânicos/química , Compostos Orgânicos/efeitos da radiação , Sonicação/métodos , Óleo de Soja/química , Óleo de Soja/efeitos da radiação , Ativação Enzimática/efeitos da radiação , Enzimas Imobilizadas , Esterificação/efeitos da radiação , Proteínas Fúngicas , Ondas de Choque de Alta Energia , Cinética , Doses de Radiação , Solventes/química , Solventes/efeitos da radiação , Especificidade por Substrato/efeitos da radiação
17.
Ultrason Sonochem ; 19(3): 440-51, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21982936

RESUMO

This work reports experimental kinetic data of solvent-free glycerolysis of olive oil using a commercial immobilized lipase (Novozym 435) under the influence of ultrasound irradiation. The experiments were performed in a mechanically stirred reactor under ultrasound irradiation, evaluating the effects of temperature (50-70 °C), enzyme concentration (2.5-10 wt%) and glycerol to oil molar ratio (0.8:1-3:1). Results show that ultrasound-assisted lipase-catalyzed glycerolysis might be a potential alternative route to conventional methods, as high contents of reaction products, especially monoglycerides, were achieved at mild irradiation power supply (~130 W) and temperature, in a relatively short reaction time (2h) and low enzyme content (7.5 wt%). To completeness, two simplified kinetic modeling approaches, based on the ordered-sequential bi bi mechanism and reaction stoichiometry, were employed to represent the experimental data, thus allowing a better understanding of the reaction kinetics.


Assuntos
Glicerol/química , Glicerol/efeitos da radiação , Lipase/química , Lipase/efeitos da radiação , Óleos de Plantas/química , Óleos de Plantas/efeitos da radiação , Sonicação/métodos , Ativação Enzimática/efeitos da radiação , Enzimas Imobilizadas , Proteínas Fúngicas , Ondas de Choque de Alta Energia , Cinética , Azeite de Oliva , Doses de Radiação , Solventes , Especificidade por Substrato/efeitos da radiação
18.
Int J Food Sci Nutr ; 62(7): 703-10, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21591987

RESUMO

The objective of this work is to evaluate the effects of the addition of dried extract from mate leaves on the oxidative stability (lipid and protein), microbiological characteristics (lactic and Micrococcaceae bacteria) and sensory attributes of formulations of Italian-type sausages. The different Italian-type sausages formulations tested in this work were in agreement with the legislation in terms of chemical and microbiological parameters. During storage, the formulation with 0.4 wt% of mate leaves extract presented lower thiobarbituric acid reactive substances and carbonyl values compared with the control, proving the antioxidant action of the extract. The sensory characteristics of flavour, texture and global acceptation were not affected by the addition of mate extract compared with the formulation with artificial antioxidant.


Assuntos
Antioxidantes/farmacologia , Comportamento do Consumidor , Ilex paraguariensis , Peroxidação de Lipídeos/efeitos dos fármacos , Produtos da Carne/análise , Extratos Vegetais/farmacologia , Carbonilação Proteica/efeitos dos fármacos , Animais , Gorduras na Dieta/metabolismo , Proteínas Alimentares/metabolismo , Tecnologia de Alimentos , Humanos , Oxirredução , Folhas de Planta , Paladar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
19.
Ultrason Sonochem ; 18(5): 981-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21256792

RESUMO

This work reports the enzymatic production of mono- and diacylglycerols under the influence of ultrasound irradiation, in a solvent-free system, with and without the presence of surfactants at a constant temperature of 65°C, glycerol to oil molar ratio of 2:1 and a commercial immobilized lipase (Novozym 435) as catalyst. For this purpose, two operation modes were adopted: the use of a sonotrode (ultrasonic probe), without agitation, varying reaction time, irradiation amplitude (25-45% of the total power) and type of surfactant, and a mechanically stirred reactor (600 rpm) under ultrasound irradiation in a water bath, testing different surfactants. Results show that very satisfactory MAG and DAG yields, above 50 wt.%, can be obtained without the use of surfactant, at mild irradiation power supply (∼130 W), with no important enzyme activity losses verified, in a relatively short reaction time (2h), and low enzyme content (7.5 wt.%). Also, reaction kinetic results show that contents of MAG+DAG as high as ∼65 wt.% can be achieved at longer times (6h), indicating a promising route for producing MAG and DAG using ultrasound irradiation.


Assuntos
Diglicerídeos/síntese química , Diglicerídeos/efeitos da radiação , Manipulação de Alimentos/métodos , Óleos de Plantas/química , Óleos de Plantas/efeitos da radiação , Sonicação/métodos , Diglicerídeos/isolamento & purificação , Lipase/química , Azeite de Oliva , Doses de Radiação , Solventes/química
20.
J Sci Food Agric ; 90(9): 1460-6, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20549797

RESUMO

BACKGROUND: This paper reports the catalytic oxidation of the concentrated orange oil phase using the complexes [Fe(III)(BMPP)Cl(micro-O)Fe(III)Cl(3)], [Cu(II)(BTMEA)(2)Cl]Cl and [Co(II)(BMPP)]Cl(2) biomimetic to methane monooxygenase enzyme as catalysts and hydrogen peroxide as oxidant. RESULTS: The reaction products of oil oxidation, mainly nootkatone, were identified by gas chromatography/mass spectrometry. A screening of catalysts was performed through a full 2(3) experimental design, varying the temperature from 30 to 70 degrees C, the catalyst concentration from 7.0 x 10(-4) to 1.5 x 10(-3) mol L(-1) and the oxidant/substrate molar ratio from 1:1 to 3:1. The results of reaction kinetics employing the most promising catalysts showed that conversions to nootkatone of up to 8% were achieved after 16 h at 70 degrees C. CONCLUSION: The results obtained in this study in terms of nootkatone production should be considered encouraging, since a real, industrially collected, raw material, instead of pure valencene, was employed in the reaction experiments, with a final content about ten times that present in the original concentrated oil.


Assuntos
Materiais Biomiméticos/química , Complexos de Coordenação/química , Metaloproteínas/química , Oxigenases/química , Óleos de Plantas/química , Materiais Biomiméticos/síntese química , Catálise , Complexos de Coordenação/síntese química , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Peróxido de Hidrogênio/química , Cinética , Concentração Osmolar , Oxidantes/química , Oxirredução , Oxigenases/metabolismo , Sesquiterpenos Policíclicos , Sesquiterpenos/análise , Sesquiterpenos/síntese química , Sesquiterpenos/química
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