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1.
Braz. j. biol ; 79(2): 213-219, Apr.-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989457

RESUMO

Abstract Species of the Carapa spp. complex, occurring in the Neotropics, Africa and India, have multiple uses, including timber, with the seed oil being used in phyto-pharmaceutical products and cosmetics. This study aimed to determine the thermal ranges of the germination process, comparing germination criteria used by seed physiologists and seed technologists, and to suggest recommendations for seed quality assessment. Germination was assessed at constant temperatures between 10 ─ 40 °C using three germination criteria: (1) radicle length ≥ 0.5 cm (physiological criterion); (2) epicotyl length ≥ 1 cm; and (3) epicotyl length ≥ 5 cm (criterion for seed quality tests). The base temperature was similar for the three criteria and ranged between 10 ─ 2 °C. The Maguire's Speed Index indicated 30 °C as most adequate. However, the upper temperature limit differed: for radicle protrusion it was above 40 ºC; and for both epicotyl lengths, it was between 35 ─ 40 °C. Seed coat removal accelerated the germination process of these recalcitrant seeds, and is recommended for seed quality assessment, which allows completion of the germination trial in approximately one month.


Resumo As espécies do complexo Carapa spp. ocorrem na região Neotropical, na África e na Índia, têm usos múltiplos, fornece madeira de valor comercial e o óleo extraído das sementes tem uso fitoterápico e cosmético. O objetivo deste trabalho foi determinar a faixa térmica tolerável do processo germinativo, comparando os critérios de germinação utilizados pelos fisiologistas e os tecnólogos de sementes, e sugerir recomendações para a avaliação da qualidade das sementes. A germinação foi avaliada em temperaturas constantes entre 10 e 40 °C utilizando três critérios de germinação: (1) formação da radícula ≥ 0,5 cm (critério fisiológico); (2) alongamento de epicótilo ≥ 1 cm; e (3) alongamento de epicótilo ≥ 5 cm (critério para testes de qualidade de sementes). A temperatura de base foi semelhante para os três critérios entre 10 e 12 °C. O índice de velocidade de Maguire indicou 30 °C como a temperatura mais adequada. O limite superior de temperatura diferiu entre os critérios, sendo acima de 40 ºC para protrusão da radícula e para ambos os alongamentos de epicótilo entre 35 e 40 °C. A remoção do tegumento de semente acelerou o processo de germinação dessas sementes recalcitrantes sendo recomendada para a avaliação da qualidade da semente, o que permite concluir o teste de germinação em aproximadamente um mês.


Assuntos
Germinação/efeitos da radiação , Germinação/fisiologia , Meliaceae/crescimento & desenvolvimento , Meliaceae/efeitos da radiação , Meliaceae/fisiologia , Agricultura , Sementes/fisiologia , Temperatura Alta
2.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467182

RESUMO

Abstract Species of the Carapa spp. complex, occurring in the Neotropics, Africa and India, have multiple uses, including timber, with the seed oil being used in phyto-pharmaceutical products and cosmetics. This study aimed to determine the thermal ranges of the germination process, comparing germination criteria used by seed physiologists and seed technologists, and to suggest recommendations for seed quality assessment. Germination was assessed at constant temperatures between 10 40 °C using three germination criteria: (1) radicle length 0.5 cm (physiological criterion); (2) epicotyl length 1 cm; and (3) epicotyl length 5 cm (criterion for seed quality tests). The base temperature was similar for the three criteria and ranged between 10 2 °C. The Maguires Speed Index indicated 30 °C as most adequate. However, the upper temperature limit differed: for radicle protrusion it was above 40 ºC; and for both epicotyl lengths, it was between 35 40 °C. Seed coat removal accelerated the germination process of these recalcitrant seeds, and is recommended for seed quality assessment, which allows completion of the germination trial in approximately one month.


Resumo As espécies do complexo Carapa spp. ocorrem na região Neotropical, na África e na Índia, têm usos múltiplos, fornece madeira de valor comercial e o óleo extraído das sementes tem uso fitoterápico e cosmético. O objetivo deste trabalho foi determinar a faixa térmica tolerável do processo germinativo, comparando os critérios de germinação utilizados pelos fisiologistas e os tecnólogos de sementes, e sugerir recomendações para a avaliação da qualidade das sementes. A germinação foi avaliada em temperaturas constantes entre 10 e 40 °C utilizando três critérios de germinação: (1) formação da radícula 0,5 cm (critério fisiológico); (2) alongamento de epicótilo 1 cm; e (3) alongamento de epicótilo 5 cm (critério para testes de qualidade de sementes). A temperatura de base foi semelhante para os três critérios entre 10 e 12 °C. O índice de velocidade de Maguire indicou 30 °C como a temperatura mais adequada. O limite superior de temperatura diferiu entre os critérios, sendo acima de 40 ºC para protrusão da radícula e para ambos os alongamentos de epicótilo entre 35 e 40 °C. A remoção do tegumento de semente acelerou o processo de germinação dessas sementes recalcitrantes sendo recomendada para a avaliação da qualidade da semente, o que permite concluir o teste de germinação em aproximadamente um mês.

3.
Academic Journal of Second Military Medical University ; (12): 81-85, 2017.
Artigo em Chinês | WPRIM | ID: wpr-838355

RESUMO

Objective To investigate the characteristics of hyaluronic acid-uricase multivesicular liposomes (UHMVLs) in vitro and the pharmacodynamics of UHMVLs in rats. Methods UHMVLs was prepared by multiple emulsion method. The entrapment efficiency and physicochemical properties were detected. Twelve healthy male SD rats were enrolled in this study. The rat model of hyperuricemia was established with hypoxanthine and oteracil potassium, while the normal rats (n=3) were set as controls. Intravenous UHMVLs, uricase (UC) and nothing were given to the rats of UHMVLs group (n=3), UC group (n=3) and hyperuricemia model group (n=3), respectively; the levels of serum uric acid (UA) were detected in rats of the 4 groups. Results The average entrapment efficiency of UHMVLs was (62.48±3.87)%. The optimum temperatures of UHMVLs and UC were 40°, while the optimum pH values of UHMVLs and free UC were 8.0 and 8.5, respectively. The activity of UC in UHMVLs was significantly higher than that in free UC at the same temperature (20-70°) and pH value (6.5-9.5) (P<0.05). UHMVLs was more effective than free UC in decreasing serum UA in rats with hyperuricemia at all time points (P<0.05), except for 1 h, 36 h and 48 h. Conclusion Under the same condition, UHMVLs can improve not only the activity, but also the stability of UC. UHMVLs is more effective in decreasing serum uric acid in rats compared with free UC, which may pave a way for clinical application of UC.

4.
Ciênc. rural (Online) ; 47(10): e20160824, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1044864

RESUMO

ABSTRACT: The objective of this study was to determine the cardinal temperatures for the planting-emergence phase of gladiolus. A controlled environment experiment was performed in a growth chamber in the Universidade Federal do Pampa - Campus Itaqui, using the completely randomized experimental design with 12 temperature treatments (5°C, 7°C, 10°C, 13°C, 16°C, 18°C, 20°C, 22°C, 25°C, 30°C, 33°C, 35°C) and ten replicates. Corms of the cultivar 'Amsterdam' were planted at a depth of 10cm in 1.7dm3 pots. Every day the date of emergence of the gladiolus plants was observed. Then for each treatment, the emergence rate was calculated as the inverse of the duration of the budding phase, and estimated data were achieved employing the non-linear model of simulation. The lower base and upper base temperatures were identified at the non-emergence temperatures. To estimate the optimum temperature, the root of mean square error was used. Between 22 and 25ºC the planting-emergence phase was reported to be completed in a shorter time span, although the smaller root mean square error was achieved at 22.5ºC. The cardinal temperatures of the planting-emergence phase of gladiolus, lower base, optimum and upper base temperature were 5°C, 22.5°C and 35°C, respectively.


RESUMO: Objetivou-se determinar as temperaturas cardinais para a fase de plantio-emergência de cormos de gladíolo. O experimento foi conduzido em ambiente controlado, em câmara de crescimento localizada no laboratório de fitotecnia do Campus Itaqui da Universidade Federal do Pampa. O delineamento experimental foi inteiramente casualizado sendo os tratamentos 12 níveis térmicos (5°C, 7°C, 10°C, 13°C, 16°C, 18°C, 20°C, 22°C, 25°C, 30°C, 33°C, 35°C), com dez repetições. Utilizou-se a cultivar 'Amsterdam', sendo o plantio dos cormos a 10cm de profundidade. Foi observada diariamente a data de emergência das plantas de gladíolo. A taxa de emergência foi calculada para cada tratamento como o inverso da duração da fase de brotação, sendo os dados estimados obtidos através de um modelo não linear de simulação. Nas temperaturas que não houve emergência, definiu-se a temperatura basal inferior e basal superior. Para determinar a temperatura ótima, utilizou-se a raiz do quadrado médio do erro. Na faixa de temperatura de 22ºC a 25ºC a fase plantio-emergência é completada em menor tempo, porém a menor raiz quadrada do erro foi obtida na temperatura de 22,5ºC. As temperaturas cardinais para a fase plantio-emergência de gladíolo são temperatura basal inferior de 5°C, temperatura ótima de 22,5°C e temperatura basal superior de 35°C.

5.
Artigo em Inglês | IMSEAR | ID: sea-179723

RESUMO

Aim: Partial purification and characterization of amyloglucosidase from an insect were carried out to determine the physicochemical properties of the enzyme. Study Design: It was designed to dissect digestive tracts from the American cockroach, Periplaneta americana, and to investigate the properties of the gut amyloglucosidase with a view to predicting possible industrial and pest control applications. Place and Duration of Study: The study was carried out in the Insect Physiology Laboratory of the Department of Crop Production and Protection and Department of Biochemistry, Obafemi Awolowo University, Ile-Ife, Nigeria between June and October, 2013. Methodology: Newly emerged cockroaches were dissected in ice-cold phosphate buffer and digestive tracts were collected to prepare the crude enzyme extract. Standard bioassays were constituted to purify and characterize amyloglucosidase. Results: The purification had a 71.6% yield and a specific activity of 2.53 U/mg protein. On soluble starch, the enzyme exhibited optimum activity at pH 4.0 with a Michaelis constant (Km) of 1.67 mg/ml and a maximum velocity (Vmax) of 10mg/ml/min. Amyloglucosidase activity was enhanced by Mn2+ but it was slightly inhibited by Sn2+, Mg2+ and Ni2+, while Zn2+ caused a 50% inhibition. Optimum temperature for the partially purified enzyme was 40°C and it lost about 90% of its original activity when incubated beyond 20 min at 60°C. Conclusion: Obtained results suggested that starch degradation using amyloglucosidase from P. americana could be done around pH 4 and at temperature around 40°C. This work appears to give the first report on physicochemical properties of amyloglucosidase in insects. Further studies would be needed to determine the possibility of using molecular techniques in inducing amyloglucosidase- Zn2+ complex in P. americana and to find a probable source of thermophilic amyloglucosidase which would be of importance in an industrial context.

6.
Electron. j. biotechnol ; 15(1): 7-7, Jan. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640533

RESUMO

Background: Support vector machine (SVM), a novel powerful machine learning technology, was used to develop the non-linear quantitative structure-property relationship (QSPR) model of the G/11 xylanase based on the amino acid composition. The uniform design (UD) method was applied to optimize the running parameters of SVM for the first time. Results: Results showed that the predicted optimum temperature of leave-one-out (LOO) cross-validation fitted the experimental optimum temperature very well, when the running parameter C, ξ, and γ was 50, 0.001 and 1.5, respectively. The average root-mean-square errors (RMSE) of the LOO cross-validation were 9.53ºC, while the RMSE of the back propagation neural network (BPNN), was 11.55ºC. The predictive ability of SVM is a minor improvement over BPNN, but it is superior to the reported method based on stepwise regression. Two experimental examples proved the validation of the model for predicting the optimal temperature of xylanase. Conclusion: The results indicated that UD might be an effective method to optimize the parameters of SVM, which could be used as an alternative powerful modeling tool for QSPR studies of xylanase.


Assuntos
Biologia Computacional/métodos , /química , Redes Neurais de Computação , Temperatura , Modelos Logísticos
7.
Mycobiology ; : 171-175, 2010.
Artigo em Inglês | WPRIM | ID: wpr-729470

RESUMO

Metacordyceps yongmunensis is a newly reported species from Korea, which is very similar to Cordyceps species in morphological characters. It grows on large lepidopteran pupa, and numerous white stromata grow on a single host. Mycelial growth characteristics of M. yongmunensis isolates were studied in different media and at different temperatures. Also, different carbon sources, nitrogen sources, and mineral salts were tested for mycelial growth of M. yongmunensis. Schizophyllum (mushroom) genetics complete medium plus yeast extract, Schizophyllum (mushroom) genetics minimal medium, and Martin's peptone dextrose agar produced longer colony diameters and more compact mycelial density than other media. The optimum temperature for mycelial growth was 25degrees C. Carbon sources such as sucrose, soluble starch, dextrose, glucose, dextrin, maltose, and fructose showed better mycelial growth, whereas peptone, yeast extract and tryptone resulted in the best mycelial growth of all of the nitrogen sources tested. All of the mineral salts tested showed similar growth as the control, except K2HPO4 which showed longer colony diameter and more compact mycelial density. The compact colonies were white and cottony with a greenish margin. The results showed that M. yongmunensis is an easy fungus to growas it grew from 30 to more than 50 mm in 2 wk.


Assuntos
Humanos , Ágar , Carbono , Cordyceps , População Branca , Frutose , Fungos , Glucose , Coreia (Geográfico) , Maltose , Nitrogênio , Peptonas , Fosfatos , Compostos de Potássio , Pupa , Sais , Schizophyllum , Amido , Sacarose , Leveduras
8.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM | ID: wpr-684660

RESUMO

In order to improve the optimum temperature of lipases, The Penicillum expansum lipase (PEL) gene was mutated by site-directed mutagenesis using overlap extension PCR technique. The recombinant plasmid pPIC3.5K-lip-E83V containing matant gene was expressed in Pichia pastoris GS115. The comparison experiments of the mutant PEL-E83V-GS with the wild-type PEL-GS showed that: the optimum temperature of the mutant (45℃) was higher by 5℃ than that of the wild type. The thermostability of the mutant was similar to the wild type. The enzymatic activity of the mutant was 188 U/mL at 37 ℃, which was 80% that of the wild type at the same conditions. The hydrophobic interaction may be enhanced in the surface region by the hydrophilic amino acid, Glu substituted with the hydrophobic amino acid, Val, and be responsible for the improvement of optimum temperature.

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