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1.
BMC Plant Biol ; 19(1): 120, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30935415

RESUMO

BACKGROUND: Polyunsaturated fatty acids such as linoleic acid (LA) and α-linolenic acid (ALA) are abundant in vegetable oils and are important for human health. In the body, LA and ALA are respectively converted to the omega-6 fatty acid γ-linolenic acid (GLA) and the omega-3 fatty acid stearidonic acid (SDA) by Δ6 desaturase (D6DES). Currently, dietary GLA and SDA are mainly obtained from marine organisms, but given their benefits to human health, many studies have aimed to enhance their accumulation in transgenic crops. Perilla frutescens (perilla) accumulates more ALA in its seed oil compared to other oilseed crops, making it a good candidate for the production of fatty acids via the fatty acid desaturase D6DES. RESULTS: In this study, we cloned the D6DES gene from Phytophthora citrophthora and confirmed its function in budding yeast. We then transformed the functional D6DES gene under the control of the seed-specific vicilin promoter into the perilla cultivar Yeobsil. The resulting transgenic perilla seeds accumulated significant levels of GLA and SDA, as well as putative C18:2Δ6,9 at minor levels. Developing seeds and leaves also accumulated GLA and SDA, although PcD6DES expression and GLA and SDA levels were much lower in leaves compared to developing seeds. GLA and SDA accumulated in both polar lipids and neutral lipids in mature perilla seeds expressing PcD6DES, especially in neutral lipids. Although the seed weight in PcD6DES perilla was 87-96% that of wild type, the total oil content per seed weight was similar between lines. The PcD6DES perilla plants contained very high content (over 45%) of both GLA and SDA in seed oil. CONCLUSIONS: Thus, PcD6DES perilla plants may represent a feasible alternative to traditional marine sources for the production of omega-3 oil capsules and to evening primrose seed oil for GLA as health food. In addition, these plants can be used to create other transgenic lines harboring additional genes to produce other desirable fish-oil like oils.


Assuntos
Ácidos Graxos Ômega-3/metabolismo , Perilla frutescens/metabolismo , Sementes/metabolismo , Ácido gama-Linolênico/metabolismo , Óleos de Plantas/metabolismo , Plantas Geneticamente Modificadas
2.
Food Chem ; 272: 688-693, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30309599

RESUMO

Anthocyanins are major components of purple sweet potatoes (PSP) with antioxidant, anti-obesity, and antidiabetic activity. In this study, we evaluated the hypoglycemic effects of 12 individual anthocyanins purified from PSP (Korean variety Shinzami). We separated the anthocyanins using liquid chromatography with diode array detection and electrospray ionization/mass spectrometry (LC-DAD-ESI/MS). Three anthocyanins were selected through a radical scavenging activity test. We examined whether individual anthocyanins inhibited glucose secretion in HepG2 cells (hepatic gluconeogenesis). Additionally, we determined the effect of each anthocyanin on fasting blood glucose levels in 6-week-old male C57BL/6J mice fed a 60% high-fat diet for 14 weeks. Mice were evaluated at 0, 1, 2, and 4 h after oral administration of anthocyanins (80 mg/kg), an anthocyanin-rich-fraction (80 mg/kg), positive control (metformin, 80 mg/kg), and distilled water (control). Cyanidin 3-caffeoyl-p-hydroxybenzoylsophoroside-5-glucoside (PEAK9) was the main PSP anthocyanin that inhibited hepatic glucose secretion and reduced blood glucose.


Assuntos
Antocianinas/química , Glucosídeos/química , Hipoglicemiantes/química , Ipomoea batatas/química , Animais , Antocianinas/administração & dosagem , Antocianinas/isolamento & purificação , Antioxidantes/química , Glicemia/análise , Cromatografia Líquida de Alta Pressão , Dieta Hiperlipídica , Glucosídeos/administração & dosagem , Glucosídeos/isolamento & purificação , Células Hep G2 , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/etiologia , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/isolamento & purificação , Ipomoea batatas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray
3.
Int J Mol Sci ; 19(6)2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29865165

RESUMO

Ultraviolet irradiation-induced hyperpigmentation of the skin is associated with excessive melanin production in melanocytes. Tyrosinase (TYR) is a key enzyme catalyzing the rate-limiting step in melanogenesis. TYR expression is controlled by microphthalmia-associated transcription factor (MITF) expression. Sorghum is a cereal crop widely used in a variety of foods worldwide. Sorghum contains many bioactive compounds and is beneficial to human health. However, the effects of sorghum in anti-melanogenesis have not been well characterized. In this study, the biological activity of sorghum ethanolic extract (SEE) on α-melanocyte-stimulating hormone (α-MSH)-induced TYR expression was evaluated in B16F10 melanoma cells. SEE attenuated α-MSH-induced TYR gene promoter activity through the downregulation of the transcription factor MITF. We found that paired box gene 3 (Pax3) contributes to the maximal induction of MITF gene promoter activity. Further analysis demonstrated that SEE inhibited α-MSH-induced Pax3 expression. The collective results indicate that SEE attenuates α-MSH-induced TYR expression through the suppression of Pax3-mediated MITF gene promoter activity. Targeting the Pax3-MITF axis pathway could be considered a potential strategy to increase the efficacy of anti-melanogenesis.


Assuntos
Regulação Neoplásica da Expressão Gênica , Melanoma/tratamento farmacológico , Monofenol Mono-Oxigenase/genética , Extratos Vegetais/farmacologia , Sorghum/química , alfa-MSH/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Melanoma/enzimologia , Melanoma/metabolismo , Camundongos , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Fator de Transcrição PAX3/metabolismo , Transdução de Sinais
4.
Sci Rep ; 7(1): 11175, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28894278

RESUMO

The juice of Ageratum houstonianum is used in folk medicine as an external wound healing aid for skin injuries. However, the active component of A. houstonianum and its mode of action in skin wound healing has not been investigated. This study was conducted to investigate the effect of A. houstonianum ethanolnolic extract (AHE) on the expression of aquaporin-3 (AQP3), an integral membrane protein for water and glycerol transport in keratinocytes, and to identify the structure of the A. houstonianum bioactive compound. Here, we show that AHE increased AQP3 gene expression at the transcriptional level through the p38 MAPK pathway in HaCaT cells. Furthermore, AHE ameliorated suppression of AQP3 expression caused by ultraviolet B (UVB) irradiation. Agerarin (6,7-dimethoxy-2,2-dimethyl-2H-chromene) was identified as the bioactive compound responsible for the up-regulation of AQP3 expression by enhancing the expression of the transcription factor circadian locomotor output cycles kaput (CLOCK). In conclusion, agerarin is a bioactive compound in AHE responsible for CLOCK-mediated AQP3 expression in keratinocytes.


Assuntos
Ageratum/química , Aquaporina 3/biossíntese , Relógios Circadianos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Compostos Fitoquímicos/metabolismo , Extratos Vegetais/metabolismo , Linhagem Celular , Humanos , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Transcrição Gênica/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
BMC Complement Altern Med ; 17(1): 442, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28870184

RESUMO

BACKGROUND: Agrimonia pilosa Ledeb. is a medicinal plant with physiological activities such as anti-cancer, antioxidant, anti-inflammatory activities and in vitro anti-diabetic activity. However, the effects of aqueous extracts from A. pilosa on insulin-resistant rats have not yet been examined. We investigated the effects of aqueous extract from A. pilosa on impaired glucose metabolism induced by a high-fat diet in rats. METHODS: Male Sprague-Dawley rats were assigned to the following groups: normal-fat diet (NF, n = 9); high-fat diet (HF, n = 9); high-fat diet with 0.1% A. pilosa aqueous extract (HFA, n = 10). Experimental diets were administered for 16 weeks. At the end of the treatment, liver and fat tissues were isolated, and serum was collected for biochemical analysis. RESULTS: The HF group rats had a significantly higher liver weight than the NF group rats did, and increased hepatic lipid accumulation (p < 0.05); however, supplementation with A. pilosa decreased liver weight. Blood glucose levels in the HFA group were lower than levels measured in the HF group 30, 60, and 120 min after glucose administration (p < 0.05). In addition, dietary A. pilosa supplementation decreased tumor necrosis factor α and interleukin 6 levels, while increasing serum adiponectin concentrations (p < 0.05 vs. the HF group). These effects were accompanied by reduced hepatic and adipose tissue expression of inflammation-related genes such as Tnf and Il1b (p < 0.05). CONCLUSIONS: Our findings indicate that A. pilosa aqueous extract can ameliorate insulin resistance in high-fat diet-fed rats by decreasing the inflammatory response.


Assuntos
Agrimonia/química , Intolerância à Glucose/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Glicemia/metabolismo , Dieta Hiperlipídica/efeitos adversos , Intolerância à Glucose/etiologia , Intolerância à Glucose/imunologia , Intolerância à Glucose/metabolismo , Humanos , Insulina/metabolismo , Interleucina-6/genética , Interleucina-6/imunologia , Fígado/metabolismo , Masculino , Obesidade/tratamento farmacológico , Obesidade/etiologia , Obesidade/imunologia , Obesidade/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
6.
J Med Food ; 20(9): 855-863, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28686509

RESUMO

The innate immune response is an important host primary defense system against pathogens. γ-Oryzanol is one of the nutritionally important phytoceutical components in rice bran oil. The goal of this study was to investigate the effect of γ-oryzanol-rich extract from black rice bran (γORE) on the activation of the innate immune system. In this study, we show that γORE increased the expression of CD14 and Toll-like receptor 4 and enhanced the phagocytic activity of RAW264.7 macrophages. Furthermore, γORE and its active ingredient γ-oryzanol promoted the secretion of innate cytokines, interleukin-8, and CCL2, which facilitate phagocytosis by RAW264.7 cells. These findings suggest that γ-oryzanol in the γORE enhances innate immune responses.


Assuntos
Imunidade Inata/efeitos dos fármacos , Oryza/química , Extratos Vegetais/farmacologia , Animais , Quimiocina CCL2/genética , Quimiocina CCL2/imunologia , Interleucina-8/genética , Interleucina-8/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Fenilpropionatos/farmacologia , Extratos Vegetais/química , Células RAW 264.7 , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia
7.
J Med Food ; 20(3): 309-319, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28296593

RESUMO

Abnormal activation of adipogenesis in mesenchymal stem cells (MSCs) and preadipocyte cells is associated with human metabolic disorders, such as osteoporosis and obesity. This study investigated the biological effects of protocatechuic acid (PCA) on the modulation of osteogenesis and adipogenesis in cultured cells. PCA stimulation of MSCs significantly increased intracellular mineralization during osteogenesis, but reduced lipid accumulation in both MSCs and 3T3-L1 preadipocyte cells during adipogenesis. Reverse transcription-polymerase chain reaction and immunoblotting analyses showed a dose-dependent upregulation of proosteogenic runt-related transcription factor 2 due to induction of ß-catenin. PCA reduced the expression of proadipogenic transcription factor, peroxisome proliferator-activated receptor-γ, and suppressed its promotor activity. These results suggest PCA exerts stimulatory effects on the osteogenesis of MSCs and inhibitory effects on the adipogenesis of MSCs and 3T3-L1 cells. PCA may contribute to maintain a coordinated metabolic balance between adipogenesis and osteogenesis, and thus may be useful for the prevention and alleviation of osteoporosis and obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Hidroxibenzoatos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Linhagem Celular , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , PPAR gama/genética , PPAR gama/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
8.
J Ind Microbiol Biotechnol ; 44(6): 845-855, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28190109

RESUMO

Microbial enhanced oil recovery (MEOR) is an emerging oil extraction technology that utilizes microorganisms to facilitate recovery of crude oil in depleted petroleum reservoirs. In the present study, effects of wheat bran utilization were investigated on stimulation of indigenous MEOR. Biostimulation conditions were optimized with the response surface methodology. The co-application of wheat bran with KNO3 and NH4H2PO4 significantly promoted indigenous MEOR (IMEOR) and exhibited sequential aerobic (O-), facultative (An-) and anaerobic (A0-) metabolic stages. The surface tension of fermented broth decreased by approximately 35%, and the crude oil was highly emulsified. Microbial community structure varied largely among and in different IMEOR metabolic stages. Pseudomonas sp., Citrobacter sp., and uncultured Burkholderia sp. dominated the O-, An- and early A0-stages. Bacillus sp., Achromobacter sp., Rhizobiales sp., Alcaligenes sp. and Clostridium sp. dominated the later A0-stage. This study illustrated occurrences of microbial community succession driven by wheat bran stimulation and its industrial potential.


Assuntos
Fibras na Dieta , Petróleo , Bactérias/isolamento & purificação , Fermentação , Petróleo/metabolismo , Petróleo/microbiologia , Triticum
9.
Biol Res ; 49(1): 41, 2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-27716424

RESUMO

BACKGROUND: Asthma is an increasing global health problem, and novel strategies to prevent or ameliorate the condition are needed. Here, the effects of 80 % ethanol extracts of Salvia plebeia R. Br. (SE) on an induced inflammatory response were investigated. RESULTS: Salvia plebeia R. Br. inhibited production of pro-inflammatory cytokines, such as TNF-α and IL-6, as well as nitric oxide (NO) in LPS-stimulated RAW 264.7 cells. NO and pro-inflammatory cytokine production was suppressed more effectively by SE of the aerial parts (SE-A) than of the roots (SE-R) of S. plebeia. In BEAS-2B cells, both SE-A and SE-R inhibited the increase in production of the inflammatory cytokines IL-6 and IL-8. We also investigated the anti-asthmatic effects of SE in an ovalbumin (OVA)-induced BALB/c mouse model. SE-A treatment significantly reduced the number of airway eosinophils, IL-4 and IL-13 levels, mucus production, and inflammatory infiltration, as compared with the corresponding levels in the untreated, OVA-induced mice, and had similar effects to dexamethasone. CONCLUSIONS: Salvia plebeia ethanol extract ameliorated the induced inflammatory response in RAW 264.7 and BEAS-2B cells, with more effective inhibition noted for SE-A than for SE-R. SE-A treatment was effective in improving the histopathological changes in the lungs of asthma model mice via modulation of eosinophils and Th2 cytokines. These results suggest that SE-A can be considered as a therapeutic agent that can potentially relieve asthma.


Assuntos
Antiasmáticos/farmacologia , Anti-Inflamatórios/farmacologia , Asma/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Animais , Asma/induzido quimicamente , Canfanos , Células Cultivadas , Citocinas/análise , Citocinas/efeitos dos fármacos , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Etanol/farmacologia , Feminino , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/análise , Ovalbumina , Panax notoginseng , Componentes Aéreos da Planta/química , Células RAW 264.7 , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Salvia miltiorrhiza
10.
Vet Parasitol ; 206(3-4): 115-22, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25468015

RESUMO

This study was conducted to investigate the effects of in ovo administration of selenium (Se) incorporated into hydrolyzed soybean protein (B-Taxim [BT]) on protection against experimental avian necrotic enteritis (NE). Broiler eggs were injected with either 100 µl of PBS alone (BT0), or 20 or 40 µg/egg of BT in PBS (BT20, BT40) at 18 days of embryogenesis. On day 14 post-hatch, the chickens were uninfected or orally infected with 1.0 × 10(4) oocysts of Eimeria maxima (E. maxima). On day 18 post-hatch, E. maxima-infected chickens were orally infected with 1.0 × 10(9) CFU of Clostridium perfringens (C. perfringens). Compared with untreated and infected BT0 controls, BT20 and/or BT40 birds showed increased body weights, decreased fecal shedding of E. maxima oocysts, lower serum α-toxin and NetB levels, increased levels of serum antibodies against C. perfringens α-toxin and NetB toxin, decreased levels of serum malondialdehyde, reduced serum catalase and superoxide dismutase catalytic activities, and increased intestinal levels of gene transcripts encoding interleukin (IL)-1ß, IL-6, IL-8, and peroxiredoxin-6, but decreased levels of transcripts for catalase and glutathione peroxidase. Interestingly, transcript levels for inducible nitric oxide synthase and paraoxonase/arylesterase 2 were decreased in the BT20 group and increased in the BT40 group, compared with BT0 controls. These results indicate that in ovo administration of broiler chickens with a Se-containing protein hydrolysate enhanced protection against experimental NE possibly by altering the expression of proinflammatory and anti-oxidant genes and their downstream pathways.


Assuntos
Galinhas/imunologia , Infecções por Clostridium/veterinária , Clostridium perfringens/efeitos dos fármacos , Enterite/veterinária , Doenças das Aves Domésticas/prevenção & controle , Selênio/farmacologia , Animais , Antioxidantes/metabolismo , Galinhas/microbiologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/prevenção & controle , Citocinas/metabolismo , Enterite/microbiologia , Enterite/prevenção & controle , Necrose/veterinária , Óvulo/metabolismo , Doenças das Aves Domésticas/microbiologia
11.
BMC Complement Altern Med ; 12: 260, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23259680

RESUMO

BACKGROUND: Postmenopausal women experience estrogen deficiency-related menopausal symptoms (e.g., hot flashes and mood swings) and a dramatic increase in the incidence of chronic diseases. Although estrogen-replacement therapy (ERT) can reduce mortality from cardiovascular disease and improve osteoporosis and menopausal symptoms, its side effects have limited recent use. This study investigated the estrogen-like activity of aqueous extract from Agrimonia pilosa Ledeb. METHODS: The estrogenic activity of A. pilosa was investigated by using several in vitro assays. The binding activity of A. pilosa on estrogen receptors was examined using a fluorescence polarization-based competitive binding assay. The proliferative activity of A. pilosa was also examined using MCF-7 cells. Furthermore, the effect of A. pilosa on the expression of 3 estrogen-dependent genes was assessed. RESULTS: Using liquid chromatography-mass spectrometry, the 3 major peaks of A. pilosa aqueous extract were identified as apigenin-hexose, luteolin-glucuronide, and apigenin-glucuronide. The aqueous extract induced the proliferation of estrogen receptor-positive MCF-7 cells (p < 0.05). A. pilosa-stimulated proliferation was blocked on adding the estrogen antagonist ICI 182,780. Moreover, A. pilosa treatment increased the mRNA expression of the estrogen-responsive genes pS2 and PR (p < 0.05). CONCLUSIONS: These results suggest A. pilosa can be used to improve estrogen deficiency-related menopausal symptoms or to treat diseases in postmenopausal women.


Assuntos
Agrimonia/química , Proliferação de Células/efeitos dos fármacos , Estrogênios/deficiência , Flavonoides/farmacologia , Fitoestrógenos/farmacologia , Extratos Vegetais/farmacologia , Receptores de Estrogênio/efeitos dos fármacos , Antagonistas de Estrogênios/farmacologia , Feminino , Flavonoides/análise , Humanos , Células MCF-7 , Menopausa , Fitoestrógenos/análise , Fitoterapia , Extratos Vegetais/química , RNA Mensageiro/metabolismo , Receptores de Estrogênio/metabolismo , Fator Trefoil-1 , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
12.
Biochem Biophys Res Commun ; 370(2): 322-6, 2008 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18381065

RESUMO

4-Hydroxyphenylpyruvate dioxygenase (HPPD) is a Fe(II)-dependent, non-heme oxygenase that converts 4-hydroxyphenylpyruvate to homogentisate. Essential cofactors, such as plastoquinone and tocopherol, are produced by HPPD-dependent anabolic pathways in plants. To isolate a novel hppd using culture-independent method, a cosmid metagenomic library was constructed from soil in Korea. Screening of Escherichia coli metagenomic libraries led to the identification of a positive clone, YS103B, producing dark brown pigment in Luria-Bertani medium supplemented with l-tyrosine. In vitro transposon mutagenesis of YS103B showed that the 1.3kb insert was sufficient to produce the hemolytic brown pigment. Sequence analysis of YS103B disclosed one open reading frame encoding a 41.4kDa protein with the well-conserved prokaryotic oxygenase motif of the HPPD family of enzymes. The HPPD-specific beta-triketone herbicide, sulcotrione, inhibited YS103B pigmentation. The recombinant protein expressed in E. coli generated homogentisic acid. Thus, we present the successful heterologous expression of a previously uncharacterized hppd gene from an uncultured soil bacterium.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase/genética , 4-Hidroxifenilpiruvato Dioxigenase/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Microbiologia do Solo , 4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , Sequência de Aminoácidos , Proteínas de Bactérias/antagonistas & inibidores , Células Cultivadas , Clonagem Molecular , Cicloexanonas/farmacologia , Escherichia coli/genética , Genoma Bacteriano , Biblioteca Genômica , Herbicidas/farmacologia , Mesilatos/farmacologia , Dados de Sequência Molecular , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Análise de Sequência de Proteína
13.
Cryo Letters ; 26(2): 103-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15897962

RESUMO

Changes in moisture content (MC), sucrose and glycerol concentration in garlic shoot tips were monitored during loading and unloading with PVS3 solution. Upon PVS3 treatment, shoot tip MC decreased rapidly and sucrose and glycerol concentrations increased rapidly during the first 30 min. Sucrose and glycerol concentrations increased more slowly thereafter. Shoot tip MC in after PVS3 treatment was affected by their size, but not by sucrose concentration of the preculture medium. As the size of shoot tips increased, so their MC increased after PVS3 treatment. However, sucrose and glycerol concentrations decreased after PVS3 incubation, and concentrations in dehydrated shoot tips were much lower than those measured in non-air dried controls. During unloading with 1.2 M sucrose medium, shoot tip MC increased rapidly during the first 10 min, whereas glycerol concentration decreased steadily over 90 min. Loading and unloading of PVS3 solution in garlic shoot tips follows the principle of solute bulk flow.


Assuntos
Criopreservação/métodos , Alho/metabolismo , Glicerol/farmacocinética , Brotos de Planta/metabolismo , Sacarose/farmacocinética , Crioprotetores/farmacocinética , Dessecação , Alho/ultraestrutura , Microscopia Eletrônica de Transmissão , Brotos de Planta/ultraestrutura , Água/metabolismo
14.
Cryo Letters ; 26(1): 33-44, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15772711

RESUMO

The thermal behavior of garlic shoot tips was analyzed during the course of a vitrification protocol using the PVS3 vitrification solution. The size of shoot tips did not significantly influence the thermal behavior of garlic shoot tips. Though there was no significance, endo-thermal enthalpy from melting of crystalline ice increased as preculture duration increased to 6 days. Preculture on medium with 0.5 M sucrose significantly lowered exo- and endothermal enthalpies of dehydration-control shoot tips. By contrast, after dehydration with PVS3 solution, the concentration of sucrose in preculture medium had no significant effect on the value of enthalpies. A big thermal event was observed in garlic shoot tips air-dried for 1-3 h before dehydration. Both vitrification solution and dehydration duration significantly (P < 0.0001) influenced exo- and endothermal enthalpies. After dehydration with PVS1, PVS2, Fahy or Steponkus solutions for 120 min, only a small peak was detected in some shoot tips, but recovery of cryopreserved shoot tips was low. Dehydration duration with PVS3 solution significantly (P < 0.0001) influenced exo- and endothermal enthalpies and onset temperatures during cooling and warming. After dehydration for 150 and 180 min with PVS3 vitrification solution, no crystallization was observed during cooling and warming in most replicates, and recovery of cryopreserved shoot tips was highest (> 80%). There was a significant (P < 0.001) negative correlation between moisture content of shoot tips and concentration of sucrose and glycerol, and regeneration of cryopreserved shoot tips. By contrast, there was a significant (P < 0.001) positive correlation between MC and enthalpy of ice melting, and onset temperature of crystallization. Overall, the results of the analysis of the thermal behavior of garlic shoot tips coincide very well with their recovery after cryopreservation and provide a very useful tool for the establishment and optimization of cryopreservation protocols.


Assuntos
Criopreservação/métodos , Alho/química , Brotos de Planta/química , Criopreservação/instrumentação , Crioprotetores/farmacologia , Análise Diferencial Térmica/métodos , Alho/metabolismo , Brotos de Planta/efeitos dos fármacos , Temperatura , Água/análise , Água/metabolismo
15.
Cryo Letters ; 25(2): 90-100, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15216390

RESUMO

In this paper, the evolution of dimethylsulfoxide (DMSO) concentration and moisture content (MC) of garlic shoot tips was studied during the course of a vitrification protocol using the PVS2 vitrification solution. DMSO concentration of shoot tips increased rapidly, reaching 34.1 mg per g fresh weight after 20 min of PVS2 treatment and remained stable afterwards, while moisture content decreased from 82 to 60 percent, reaching 53 percent after 60 min. A reverse process was observed during unloading. There was a highly significant negative correlation between shoot tip moisture content and DMSO concentration during the dehydration and unloading treatments. Using unloading solutions with osmolarities between 0.42 and 2.29 Osm led to very different shoot tip MCs, between 63.55 and 81.24 percent, while DMSO concentration was between 14.83 and 19.97 mg per g fresh weight. After 24 h on recovery medium, DMSO concentration of shoot tips had decreased to 3.2 mg per g fresh weight.


Assuntos
Criopreservação/métodos , Crioprotetores/análise , Dimetil Sulfóxido/análise , Alho , Brotos de Planta/química , Água/análise
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