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1.
J Nutr ; 152(9): 2080-2087, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35511604

RESUMO

BACKGROUND: Dietary interventions for high cholesterol, a primary risk factor for cardiovascular disease, are generally considered before prescribing drugs. OBJECTIVE: This study investigated the effects of whole Great Northern beans (wGNBs) and their hull (hGNB) incorporated into a high-saturated-fat (HSF) diet on cholesterol markers and hepatic/small intestinal genes involved in cholesterol regulation. METHODS: Each of the 4 groups of 11 male golden Syrian hamsters at 9 wk old were fed a normal-fat [NF; 5% (wt:wt) of soybean oil], HSF [5% (wt:wt) of soybean oil + 10% (wt:wt) of coconut oil], HSF+5% (wt:wt) wGNB, or HSF+0.5% (wt:wt) hGNB diet for 4 wk. Cholesterol markers and expression of genes involved in cholesterol metabolism and absorption were analyzed from plasma, liver, intestinal, and fecal samples. Data were analyzed by 1-factor ANOVA and Pearson correlations. RESULTS: Compared with the HSF group, the HSF+wGNB group had 62% and 85% lower plasma and liver cholesterol and 3.6-fold and 1.4-fold greater fecal excretion of neutral sterol and bile acid, respectively (P ≤ 0.05). The HSF+hGNB group had 54% lower plasma triglycerides (P < 0.001) and 53% lower liver esterified cholesterol (P = 0.0002) than the HSF group. Compared with the HSF group, the expression of small intestinal Niemann-Pick C1 like 1 (Npc1l1), acyl-coenzyme A:cholesterol acyltransferase 2 (Acat2), and ATP binding cassette transporter subfamily G member 5 (Abcg5) were 75%, 70%, and 49% lower, respectively, and expression of hepatic 3-hydroxy-3-methylglutaryl CoA reductase (Hmgr) was 11.5-fold greater in the HSF+wGNB group (P ≤ 0.05). CONCLUSIONS: Consumption of wGNBs resulted in lower cholesterol concentration in male hamsters fed an HSF diet by promoting fecal cholesterol excretion, most likely caused by Npc1l1 and Acat2 suppression. The hGNB may partially contribute to the cholesterol-lowering effect of the wGNBs.


Assuntos
Phaseolus , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Animais , Colesterol , Cricetinae , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Masculino , Mesocricetus , Óleo de Soja
2.
J Nutr ; 149(6): 996-1003, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31006805

RESUMO

BACKGROUND: Pinto beans contain multiple active agents such as polyphenols, flavonoids, and saponins, and have been shown to lower cholesterol, but the mechanisms involved in this effect have not been explored. OBJECTIVE: This study was to investigate the changes in cholesterol metabolism in response to whole pinto beans (wPB) and their hulls (hPB) supplemented into a diet rich in saturated fat and the molecular mechanisms potentially responsible for these effects in hamsters. METHODS: Forty-four 9-wk-old male Golden Syrian hamsters were randomly assigned to 4 diet groups (n = 11), including a 5% (wt:wt) fat diet [normal-fat diet (NF)], a 15% (wt:wt) fat diet [diet rich in saturated fat (HSF), saturated fatty acids accounted for 70% of total fatty acids], or HSF supplemented with 5% (wt:wt) wPB or 0.5% (wt:wt) hPB for 4 wk. Plasma, liver, intestinal, and fecal samples were collected to evaluate multiple cholesterol markers and gene targets. RESULTS: The plasma non-high-density lipoprotein (non-HDL) concentration was significantly reduced in the wPB- and hPB-supplemented groups by 31.9 ± 3.5% and 53.6 ± 3.2%, respectively, compared with the HSF group (P < 0.01), to concentrations comparable with the NF group. The wPB-supplemented hamsters had significantly lower liver cholesterol (45.1%, P < 0.001) and higher fecal cholesterol concentrations (94.8%, P = 0.001) than those fed the HSF. The expressions of hepatic 3-hydroxy-3-methylglutaryl CoA reductase (Hmgcr) and small intestinal acyl-coenzyme A: cholesterol acyltransferase 2 (Acat2) were significantly decreased in animals administered wPB (by 89.1% and 63.8%, respectively) and hPB (by 72.9% and 47.7%, respectively) compared with their HSF-fed counterparts (P < 0.05). The wPB normalized the expression of Acat2 to the level of the NF group. CONCLUSION: Pinto beans remediated high cholesterol induced by HSF in male hamsters by decreasing hepatic cholesterol synthesis and intestinal cholesterol absorption, effects which were partially exerted by the hulls.


Assuntos
Colesterol/sangue , Colesterol/genética , Gorduras na Dieta/administração & dosagem , Phaseolus , Fenômenos Fisiológicos da Nutrição Animal , Animais , Anticolesterolemiantes/administração & dosagem , Cricetinae , Dieta , Dieta Hiperlipídica , Expressão Gênica , Homeostase , Intestino Delgado/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Mesocricetus , Phaseolus/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
3.
Phytother Res ; 33(2): 319-326, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30375074

RESUMO

Novel treatments are needed to prevent candidiasis/candidemia infection due to the emergence of Candida species resistant to current antifungals. Considering the yeast-to-hyphae switch is a critical factor to Candida albicans virulence, phenols common in plant sources have been reported to demonstrating their ability to prevent dimorphism. Therefore, phenols present in many agricultural waste stress (ferulic (FA) and gallic (GA) acid) were initially screened in isolation for their yeast-to-hyphae inhibitory properties at times 3, 6, and 24 hr. Both FA and GA inhibited 50% of hyphae formation inhibitory concentration (IC50 ) but at a concentration of 8.0 ± 0.09 and 90.6 ± 1.05 mM, respectively, at 24 hr. However, the inhibitory effect of FA increased by 1.9-2.6 fold when combined with different GA concentrations. GA and FA values decreased even lower when sinapic acid (SA) was added as a third component. As evidenced by concave isobolograms and combination indexes less than 1, both GA:F A and GA:FA:SA combinations acted synergistically to inhibit 50% hyphae formation at 24 hr. Lastly, acetylation of histone H3 lysine 56 acetylation (H3K56) was higher in response to the triple phenolic cocktail (using the IC50 24 hr inhibitory concentration level) comparable with the nontreated samples, indicating that the phenols inhibited hyphal growth in part by targeting H3K56 acetylation.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Hifas/efeitos dos fármacos , Acetilação/efeitos dos fármacos , Candida albicans/fisiologia , Candidíase/metabolismo , Candidíase/microbiologia , Ácidos Cumáricos/farmacologia , Sinergismo Farmacológico , Ácido Gálico/farmacologia , Hifas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Regulação para Cima/efeitos dos fármacos , Virulência/efeitos dos fármacos
4.
Molecules ; 24(5)2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30862073

RESUMO

The chemical profile and antioxidant capacity of Juniperus virginiana, J. excelsa, and J. sabina essential oil (EO) fractions as a function of time was the subject of this study. The hypothesis was that, capturing EO in sequential timeframes during hydrodistillation would generate fractions containing unique compositions and antioxidant capacity. In J. virginiana, the highest limonene (43%) was found in the 0⁻5 min oil fraction, with safrole (37%) being highest in the 10⁻20 and 20⁻40 min fractions, and elemol (34%) being highest in the 160⁻240 min fraction. In J. excelsa, α-pinene (34-36%) was the highest in the 0⁻5 min fraction and in the control (non-stop 0⁻240 min distillation) oil, limonene (39%) was the highest in the 0⁻10 min fractions and cedrol (50-53%) was the highest in the 40⁻240 min fractions. In J. sabina, sabinene (80%) was highest in the 0⁻3 min fraction. The highest antioxidant capacity of J. virginiana was demonstrated by the 5⁻10 min fraction; the one in J. sabina by the 3⁻10 min fraction; and, the one in J. excelsa, by the control. The kinetics regression models that were developed can predict EO composition of the three juniper species eluted at different timeframes. Various industries could benefit from the results from this study.


Assuntos
Destilação , Juniperus/química , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Destilação/métodos , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química
5.
Analyst ; 143(22): 5404-5416, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30302456

RESUMO

Candida albicans is an opportunistic human pathogen that can become virulent due to its ability to switch from a benign yeast to virulent hyphae phenotype. The emergence of C. albicans resistant to commonly used antifungal agents has necessitated the development of innovative treatments, which must be accompanied by an understanding of the molecular changes that occur during the phenotypic shift. For this purpose, Fourier transform mid-infrared spectroscopy in attenuated total reflectance mode (FT-mIR-ATR) was applied to monitor the structural and compositional changes in C. albicans during the yeast-to-hyphae transition. FT-mIR-ATR measurements were completed on the whole cell of C. albicans (SC5314) during hyphal formation induced by N-acetylglucosamine at 0, 1, 2, 3, 6 and 24 h. Principal component analysis separated the FT-mIR-ATR spectra into four groups that were aligned with the morphological changes captured by microscopic imaging. Spectral signatures indicating the structural and compositional modifications during the transition were identified mainly in the fatty acid region (3100-2800 cm-1), the protein and peptide region (1800-1500 cm-1), the mixed region (1500-1200 cm-1) and the polysaccharide region (1200-900 cm-1). A spectral fingerprint of the transition via a heat map was generated based on the peak shift in position. Quantitative evaluation of the spectra by curve fitting further revealed the dynamics of the cell's main components during the transition. This work provides valuable structural and functional information on the C. albicans phenotypic transition to hyphae, which has diagnostic implications.


Assuntos
Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Hifas/crescimento & desenvolvimento , Fenótipo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Componente Principal
6.
Compr Rev Food Sci Food Saf ; 13(2): 98-113, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33412650

RESUMO

Many of the sauces used in frozen meals are oil-in-water emulsions that consist of fat droplets dispersed within an aqueous medium. This type of emulsion must remain physically and chemically stable throughout processing, freezing, storage, and defrosting conditions. Knowledge of the fundamental physicochemical mechanisms responsible for the stability of emulsion-based sauces is needed to design and fabricate high-quality sauces with the desired sensory attributes. This review provides an overview of the current understanding of the influence of freezing and thawing on the stability of oil-in-water emulsions. In particular, it focuses on the influence of product composition (such as emulsifiers, biopolymers, salts, and cryoprotectants), homogenization conditions, and freezing/thawing conditions on the stability of emulsions. The information contained in this review may be useful for optimizing the design of emulsion-based sauces for utilization in commercial food products.

7.
Br J Nutr ; 110(2): 321-9, 2013 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-23302490

RESUMO

Human biotin requirements are unknown and the identification of reliable markers of biotin status is necessary to fill this knowledge gap. Here, we used an outpatient feeding protocol to create states of biotin deficiency, sufficiency and supplementation in sixteen healthy men and women. A total of twenty possible markers of biotin status were assessed, including the abundance of biotinylated carboxylases in lymphocytes, the expression of genes from biotin metabolism and the urinary excretion of biotin and organic acids. Only the abundance of biotinylated 3-methylcrotonyl-CoA carboxylase (holo-MCC) and propionyl-CoA carboxylase (holo-PCC) allowed for distinguishing biotin-deficient and biotin-sufficient individuals. The urinary excretion of biotin reliably identified biotin-supplemented subjects, but did not distinguish between biotin-depleted and biotin-sufficient individuals. The urinary excretion of 3-hydroxyisovaleric acid detected some biotin-deficient subjects, but produced a meaningful number of false-negative results and did not distinguish between biotin-sufficient and biotin-supplemented individuals. None of the other organic acids that were tested were useful markers of biotin status. Likewise, the abundance of mRNA coding for biotin transporters, holocarboxylase synthetase and biotin-dependent carboxylases in lymphocytes were not different among the treatment groups. Generally, datasets were characterised by variations that exceeded those seen in studies in cell cultures. We conclude that holo-MCC and holo-PCC are the most reliable, single markers of biotin status tested in the present study.


Assuntos
Biotina/metabolismo , Carbono-Carbono Ligases/metabolismo , Carbono-Nitrogênio Ligases/metabolismo , Linfócitos/metabolismo , Metilmalonil-CoA Descarboxilase/metabolismo , Estado Nutricional , Deficiência de Vitaminas do Complexo B/metabolismo , Adulto , Biomarcadores/metabolismo , Suplementos Nutricionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necessidades Nutricionais , RNA Mensageiro/metabolismo , Valores de Referência , Adulto Jovem
8.
J Environ Qual ; 42(6): 1815-21, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25602421

RESUMO

Coal bed methane is extracted from underground coal seams that are flooded with water. To reduce the pressure and to release the methane, the water needs to be pumped out. The resulting waste water is known as coal bed methane water (CBMW). Major concerns with the use of CBMW are its high concentrations of S, Na, dissolved Ca, Mg, SO, and bicarbonate (HCO). Irrigation water is a scarce resource in most of the western states. The objective of this study was to evaluate the effect of various amounts of CBMW on the growth, essential oil content, composition, and antioxidant activity of spearmint ( L.) and peppermint ( L.) crops that were irrigated with the water. These two crops are grown in some western states and are potential specialty crops to Wyoming farmers. The irrigation treatments were 0% CBMW (tap water only), 25% CBMW (25% CBMW plus 75% tap water), 50% CBMW (50% CBMW and 50% tap water), 75% CBMW (75% CBMW plus 25% tap water), and 100% CBMW. Analyses of the data revealed that the CBMW treatments did not affect the antioxidant capacity of spearmint or peppermint oil (242 and 377 µmol L Trolox g, respectively) or their major oil constituents (carvone or menthol). Coal bed methane water at 100% increased total phenols and total flavonoids in spearmint but not in peppermint. Coal bed methane water also affected oil content in peppermint but not in spearmint. Spearmint and peppermint could be watered with CBMW at 50% without suppression of fresh herbage yields. However, CBMW at 75 and 100% reduced fresh herbage yields of both crops and oil yields of peppermint relative to the control.

9.
Plants (Basel) ; 11(9)2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35567228

RESUMO

Sagebrush (Artemisia spp.) are dominant wild plants in large areas of the U.S., Canada and Mexico, and they include several species and subspecies. The aim was to determine if there are significant differences in essential oil (EO) yield, composition, and biological activity of sagebrush within the Bighorn Mountains, U.S. The EO yield in fresh herbage varied from 0.15 to 1.69% for all species, including 0.25-1.69% in A. tridentata var. vaseyana, 0.64-1.44% in A. tridentata var. tridentata, 1% in A. tridentata var. wyomingensis, 0.8-1.2% in A. longifolia, 0.8-1% in A. cana, and 0.16% in A. ludoviciana. There was significant variability in the EO profile between species, and subspecies. Some EO constituents, such as α-pinene (0-35.5%), camphene (0-21.5%), eucalyptol (0-30.8%), and camphor (0-45.5%), were found in most species and varied with species and subspecies. The antioxidant capacity of the EOs varied between the species and subspecies. None of the sagebrush EOs had significant antimicrobial, antimalarial, antileishmanial activity, or contained podophyllotoxin. Some accessions yielded EO with significant concentrations of compounds including camphor, eucalyptol, cis-thujone, α-pinene, α-necrodol-acetate, fragranol, grandisol, para-cymene, and arthole. Therefore, chemotypes can be selected and possibly introduced into culture and be grown for commercial production of these compounds to meet specific industry needs.

10.
J Phys Condens Matter ; 32(3): 034001, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31639105

RESUMO

The addition of various dipolar molecules is shown to affect the temperature dependence of the spin state occupancy of the much studied spin crossover Fe(II) complex, [Fe{H2B(pz)2}2(bipy)] (pz = pyrazol-1-yl, bipy = 2,2'-bipyridine). Specifically, the addition of benzimidazole results in a re-entrant spin crossover transition, i.e. the spin state starts in the mostly low spin state, then high spin state occupancy increases, and finally the high spin state occupancy decreases with increasing temperature. This behavior contrasts with that observed when the highly polar p -benzoquinonemonoimine zwitterion C6H2(…NH2)2(…O)2 was mixed with [Fe{H2B(pz)2}2(bipy)], which resulted in locking [Fe{H2B(pz)2}2(bipy)] largely into a low spin state while addition of the ethyl derivative C6H2(…NHC2H5)2(…O)2 did not appear to perturb the spin crossover transition of [Fe{H2B(pz)2}2(bipy)].

11.
Nutrients ; 12(3)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178350

RESUMO

High-resolution 1H nuclear magnetic resonance (NMR) analysis was employed to molecularly screen the lipid, lipid oxidation product (LOP), and antioxidant compositions of four natural (unrefined) cod liver oil (CLO) products. Products 1-3 were non-fermented CLOs, whilst Product 4 was isolated from pre-fermented cod livers. Supporting analytical data that were acquired included biogenic amine, flavanone, tannin, phenolic antioxidant, α-tocopherol, and oxygen radical absorbance capacity (ORAC) determinations by recommended HPLC, LC/MS/MS, or spectrophotometric methods. SDS-PAGE, HPLC, and 1H NMR analyses investigated and determined collagenous antioxidants and their molecular mass ranges. 1H NMR analysis of aldehydic LOPs was employed to explore the susceptibilities/resistivities of each CLO product to peroxidation that is induced by thermal stressing episodes (TSEs) at 180°C, or following prolonged (42 day) storage episodes at 4 and 23 °C. Product 4 displayed extremely high ORAC values, which were much greater than those of Products 1-3, and that were predominantly ascribable to significant levels of peroxidation-blocking and/or aldehyde-consuming collagenous polypeptides/peptides and ammoniacal agents therein. Significantly lower levels of toxic aldehydes were generated in the pre-fermented Product 4 during exposure to TSEs, or the above long-term storage episodes. These results confirmed the enhanced peroxidative resistivity of a fermented, antioxidant-fortified natural CLO product over those of non-fermented unrefined products. Product 4: Green Pasture Blue Ice™ Fermented Cod Liver Oil.


Assuntos
Antioxidantes/análise , Aminas Biogênicas/análise , Óleo de Fígado de Bacalhau/análise , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas em Tandem , alfa-Tocoferol/análise , Oxirredução
12.
J Nutr ; 139(8): 1445-50, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19535421

RESUMO

Studies in our laboratory have previously demonstrated in hamsters a superior cholesterol-lowering ability of plant sterol (PS) esters enriched in stearate compared with linoleate. We therefore conducted a randomized, double-blind, 2-group parallel, placebo-controlled study to test the cholesterol-lowering properties of stearate-enriched PS esters in normo- and hypercholesterolemic adults. Thirty-two adults, 16 per group with equal number of males and females in each group, participated in the 4-wk study. Participants consumed 3 g/d (1 g three times per day with meals) of either PS esters or placebo delivered in capsules. Serum LDL cholesterol concentration significantly decreased 0.42 mmol/L (11%) and the LDL:HDL cholesterol ratio decreased 10% with PS ester supplementation, whereas LDL particle size and lipoprotein subclass particle concentrations (as measured by NMR) were not affected. The percent change in LDL cholesterol was positively correlated with baseline lathosterol concentration (r = 0.729; P = 0.0014), indicating an association between the magnitude of LDL change and the rate of whole-body cholesterol synthesis. Serum campesterol (but not sitosterol) concentration significantly increased in the PS ester group. Serum tocopherol, retinol, and beta-carotene concentrations were not affected by PS ester supplementation. Thus, our findings demonstrate the usefulness of a novel stearate-enriched PS ester compound in decreasing LDL cholesterol in both normo- and hypercholesterolemic adults. The extent to which PS ester fatty acid composition affects intestinal micelle formation and cholesterol absorption in humans requires further study.


Assuntos
Anticolesterolemiantes/uso terapêutico , LDL-Colesterol/sangue , Hipercolesterolemia/tratamento farmacológico , Fitosteróis/uso terapêutico , Estearatos/uso terapêutico , Adulto , Idoso , Anticolesterolemiantes/farmacologia , Celulose/farmacologia , Celulose/uso terapêutico , Colesterol/biossíntese , Colesterol/sangue , HDL-Colesterol/sangue , Método Duplo-Cego , Feminino , Humanos , Hipercolesterolemia/sangue , Masculino , Pessoa de Meia-Idade , Fitosteróis/farmacologia , Estearatos/farmacologia
13.
Bioresour Technol ; 99(5): 1373-82, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17383177

RESUMO

Experiments were carried out on a lab supercritical CO(2) extraction system to determine the effects of extraction conditions, including mass ratio of CO(2) consumed to distillers dry grain with solubles (DDGS) extracted, extraction pressure, extraction temperature and time, on yield and composition of extracted lipids. A maximum lipid yield of 150 g/kg DDGS was achieved with a mass ratio approximately 45, an extraction pressure at 27.5 MPa, an extraction temperature at 70 degrees C and an extraction time of 4 h. Under these extraction conditions, the contents of tocols, phytosterols, policosanols and free fatty acids were 0.44, 15.6, 31.2 and 155.3 mg/g in the extract. Experimental results indicated that shorter extraction time and higher flow rate of CO(2) can achieve higher contents of tocols, phytosterols and policosanols but lower content of free fatty acids in the lipid extract. Extraction conditions had no observed effects on the composition of free fatty acids in the extract. Palmitic, oleic and linoleic acids were three main free fatty acids extracted and constituted about 94% of all free fatty acids.


Assuntos
Dióxido de Carbono/química , Grão Comestível/química , Lipídeos/química , Sorghum/química , Cromatografia em Camada Fina , Temperatura
14.
Nutr Rev ; 76(9): 693-707, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29931328

RESUMO

Nutrient overload occurs worldwide as a consequence of the modern diet pattern and the physical inactivity that sometimes accompanies it. Cells initiate multiple protective mechanisms to adapt to elevated intracellular metabolites and restore metabolic homeostasis, but irreversible injury to the cells can occur in the event of prolonged nutrient overload. Many studies have advanced the understanding of the different detrimental effects of nutrient overload; however, few reports have made connections and given the full picture of the impact of nutrient overload on cellular metabolism. In this review, detailed changes in metabolic and energy homeostasis caused by chronic nutrient overload, as well as their associations with the development of metabolic disorders, are discussed. Overnutrition-induced changes in key organelles and sensors rewire cellular bioenergetic pathways and facilitate the shift of the metabolic state toward biosynthesis, thereby leading to the onset of various metabolic disorders, which are essentially the downstream manifestations of a misbalanced metabolic equilibrium. Based on these mechanisms, potential therapeutic targets for metabolic disorders and new research directions are proposed.


Assuntos
Metabolismo Energético/fisiologia , Homeostase , Doenças Metabólicas/etiologia , Nutrientes/efeitos adversos , Hipernutrição/fisiopatologia , Animais , Humanos , Hipernutrição/complicações
15.
Biotechnol Prog ; 23(3): 687-92, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17397184

RESUMO

Culture growth and recombinant protein yield of the Pichia pastoris GS115 methanol utilization positive system were studied in response to the types and levels of metals present in the growth medium and the supplemental salts typically used for these fermentations. Magnesium and zinc were both required to support cell growth but at significantly reduced levels compared to the control. However, supplementation with calcium, cobalt, iron, manganese, iodine, boron, and molybdenum were not required to sustain cell mass. When the medium was reformulated with only zinc and magnesium, the cells grew to 12-15 generations, which are expected for high cell density fed-batch fermentations. Product yields of the recombinant protein beta-galactosidase were significantly influenced by the trace metal concentrations. By using response surface and full factorial designs, maximum protein yield occurred when the concentration of zinc salt was limited to the level necessary only to support cell mass while protein yield positively correlated to increasing levels of the remaining trace metal salts. These studies are the first to show that excess trace metals must be optimized when developing P. pastoris based fed-batch fermentations.


Assuntos
Metais/farmacologia , Pichia/efeitos dos fármacos , Proteínas Recombinantes/biossíntese , beta-Galactosidase/metabolismo , Boro/farmacologia , Cálcio/farmacologia , Divisão Celular/efeitos dos fármacos , Cobalto/farmacologia , Meios de Cultura/farmacologia , Relação Dose-Resposta a Droga , Fermentação/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Iodo/farmacologia , Ferro/farmacologia , Magnésio/farmacologia , Manganês/farmacologia , Metanol/farmacologia , Modelos Biológicos , Molibdênio/farmacologia , Pichia/genética , Pichia/metabolismo , Zinco/farmacologia , beta-Galactosidase/genética
16.
J Food Sci ; 82(7): 1588-1593, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28556199

RESUMO

Egg yolk is an essential ingredient for many food products due to its excellent functional properties such as emulsification. However, the consumers' concern of its cholesterol level has led food industry to seek solutions for its replacement. Utilization of low-fat egg yolk granules as emulsifier can be an alternative strategy. In this study, granules with low cholesterol content were separated from egg yolk by a simple method under easily scalable centrifugal conditions. The egg yolk granules isolated within 0.17 M NaCl solution achieved a 22.5% yield that was similar to that using higher centrifugation speeds and longer time. The yield of egg yolk granules increased from 25% to 32% when the yolk:water ratio was changed from 1:1 to 1:2. Mayonnaise was prepared to evaluate the emulsifying capacity of the egg yolk granules. It was found that egg yolk granules exhibited similar emulsifying activity as that of whole egg yolk, but a better emulsion stabilizing property that is evidenced by the higher viscosity of mayonnaise prepared with the granules. In addition, the viscosities of mayonnaise prepared by spray dried yolk and granules were slightly higher than the liquid counterpart, showing a further improvement by spray drying on the emulsion stabilizing properties. The mechanical spectra of mayonnaise samples by frequency sweep also suggested that granules favored the formation of stronger 3-dimensional arrangements of oil droplets and therefore a more stable emulsion. Results suggest that granules isolated within 0.17 M NaCl solution present best emulsifying properties and can be applied as whole yolk replacer in food emulsions.


Assuntos
Gema de Ovo/química , Emulsificantes , Emulsões/química , Manipulação de Alimentos/métodos , Centrifugação , Colesterol/análise , Colesterol na Dieta , Alimentos , Viscosidade
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 173: 727-732, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27788471

RESUMO

Fungicides and plant growth regulators can impact plant growth outside of their effects on fungal pathogens. Although many of these chemicals are inhibitors of mitochondrial oxygen uptake, information remains limited as to whether they are able to modify other mitochondrial constituents. Fourier transform mid-infrared spectroscopy (FT-mIR) offers a high sample throughput method to comparatively and qualitatively evaluate the effects of exogenously added compounds on mitochondrial components. Therefore the objective of this study was to determine the ability of FT-mIR to detect effects mitochondrial fractions isolated from wheat (Triticum aestivum L.) seedlings in response to several agrochemical treatments, with an emphasis on fungicides. The accessed need was to develop FT-mIR analytical and statistical routines as an effective approach to differentiate spectra obtained from chemically-treated or untreated mitochondria. An NADH-dependent oxygen uptake approach was initially used as a comparative method to determine whether the fungicides (azoxystrobin, boscalid, cyazofamid, fluazinam, isopyrazam, and pyraclostrobin) and the plant growth regulator, (trinexapac-ethyl) reduced respiration inhibition on isolated mitochondria. Pyraclostrobin was the most effective inhibitor, whereas amisulbrom did not impact oxygen uptake. However, hierarchical clustering of FT-mIR spectra of isolated mitochondria treated with these different compounds separated into clades consistent with each of their expected mode of action. Analysis of the FT-mIR amide protein region indicated that amisulbrom and pyraclostrobin interacted with the isolated wheat mitochondria. Both chemicals were statistically different from the control signifying that respiration was indeed influenced by these treatments. Moreover, the entire FT-mIR region showed differences in various biological bands thereby providing additional information on mitochondria responses to agrochemicals, if so warranted.


Assuntos
Agroquímicos/farmacologia , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Plântula/metabolismo , Triticum/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
18.
PLoS One ; 10(12): e0144120, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26641276

RESUMO

A steam distillation extraction kinetics experiment was conducted to estimate essential oil yield, composition, antimalarial, and antioxidant capacity of cumin (Cuminum cyminum L.) seed (fruits). Furthermore, regression models were developed to predict essential oil yield and composition for a given duration of the steam distillation time (DT). Ten DT durations were tested in this study: 5, 7.5, 15, 30, 60, 120, 240, 360, 480, and 600 min. Oil yields increased with an increase in the DT. Maximum oil yield (content, 2.3 g/100 seed), was achieved at 480 min; longer DT did not increase oil yields. The concentrations of the major oil constituents α-pinene (0.14-0.5% concentration range), ß-pinene (3.7-10.3% range), γ-cymene (5-7.3% range), γ-terpinene (1.8-7.2% range), cumin aldehyde (50-66% range), α-terpinen-7-al (3.8-16% range), and ß-terpinen-7-al (12-20% range) varied as a function of the DT. The concentrations of α-pinene, ß-pinene, γ-cymene, γ-terpinene in the oil increased with the increase of the duration of the DT; α-pinene was highest in the oil obtained at 600 min DT, ß-pinene and γ-terpinene reached maximum concentrations in the oil at 360 min DT; γ-cymene reached a maximum in the oil at 60 min DT, cumin aldehyde was high in the oils obtained at 5-60 min DT, and low in the oils obtained at 240-600 min DT, α-terpinen-7-al reached maximum in the oils obtained at 480 or 600 min DT, whereas ß-terpinen-7-al reached a maximum concentration in the oil at 60 min DT. The yield of individual oil constituents (calculated from the oil yields and the concentration of a given compound at a particular DT) increased and reached a maximum at 480 or 600 min DT. The antimalarial activity of the cumin seed oil obtained during the 0-5 and at 5-7.5 min DT timeframes was twice higher than the antimalarial activity of the oils obtained at the other DT. This study opens the possibility for distinct marketing and utilization for these improved oils. The antioxidant capacity of the oil was highest in the oil obtained at 30 min DT and lowest in the oil from 360 min DT. The Michaelis-Menton and the Power nonlinear regression models developed in this study can be utilized to predict essential oil yield and composition of cumin seed at any given duration of DT and may also be useful to compare previous reports on cumin oil yield and composition. DT can be utilized to obtain cumin seed oil with improved antimalarial activity, improved antioxidant capacity, and with various compositions.


Assuntos
Antimaláricos , Antioxidantes , Cuminum/química , Óleos Voláteis/química , Sementes/química , Animais , Antimaláricos/química , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Humanos
19.
J Nutr Biochem ; 26(11): 1379-84, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26303405

RESUMO

Holocarboxylase synthetase (HLCS) is the sole protein-biotin ligase in the human proteome. HLCS has key regulatory functions in intermediary metabolism, including fatty acid metabolism, and in gene repression through epigenetic mechanisms. The objective of this study was to identify food-borne inhibitors of HLCS that alter HLCS-dependent pathways in metabolism and gene regulation. When libraries of extracts from natural products and chemically pure compounds were screened for HLCS inhibitor activity, resveratrol compounds in grape materials caused an HLCS inhibition of >98% in vitro. The potency of these compounds was piceatannol>resveratrol>piceid. Grape-borne compounds other than resveratrol metabolites also contributed toward HLCS inhibition, e.g., p-coumaric acid and cyanidin chloride. HLCS inhibitors had meaningful effects on body fat mass. When Drosophila melanogaster brummer mutants, which are genetically predisposed to storing excess amounts of lipids, were fed diets enriched with grape leaf extracts and piceid, body fat mass decreased by more than 30% in males and females. However, Drosophila responded to inhibitor treatment with an increase in the expression of HLCS, which elicited an increase in the abundance of biotinylated carboxylases in vivo. We conclude that mechanisms other than inhibition of HLCS cause body fat loss in flies. We propose that the primary candidate is the inhibition of the insulin receptor/Akt signaling pathway.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Carbono-Nitrogênio Ligases/antagonistas & inibidores , Drosophila melanogaster/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Estilbenos/farmacologia , Animais , Biotinilação/efeitos dos fármacos , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Humanos , Lipase/genética , Masculino , Extratos Vegetais/farmacologia , Resveratrol , Estilbenos/metabolismo , Vitis/química
20.
Biotechnol Prog ; 18(6): 1392-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12467476

RESUMO

The methylotrophic yeast Pichia pastoris is an effective system for recombinant protein productions that utilizes methanol as an inducer, and also as carbon and energy source for a Mut(+) (methanol utilization plus) strain. Pichia fermentation is conducted in a fed-batch mode to obtain a high cell density for a high productivity. An accurate methanol control is required in the methanol fed-batch phase (induction phase) in the fermentation. A simple "on-off" control strategy is inadequate for precise control of methanol concentrations in the fermentor. In this paper we employed a PID (proportional, integral and derivative) control system for the methanol concentration control and designed the PID controller settings on the basis of a Pichia growth model. The closed-loop system was built with four components: PID controller, methanol feed pump, fermentation process, and methanol sensor. First, modeling and transfer functions for all components were derived, followed by frequency response analysis, a powerful method for calculating the optimal PID parameters K(c) (controller gain), tau(I) (controller integral time constant), and tau(D) (controller derivative time constant). Bode stability criteria were used to develop the stability diagram for evaluating the designed settings during the entire methanol fed-batch phase. Fermentations were conducted using four Pichia strains, each expressing a different protein, to verify the control performance with optimal PID settings. The results showed that the methanol concentration matched the set point very well with only small overshoot when the set point was switched, which indicated that a very good control performance was achieved. The method developed in this paper is robust and can serve as a framework for the design of other PID feedback control systems in biological processes.


Assuntos
Reatores Biológicos , Metanol/metabolismo , Pichia/crescimento & desenvolvimento , Desenho de Equipamento , Fermentação , Modelos Biológicos
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