RESUMO
BACKGROUND: Copper (Cu), an essential trace mineral regulating multiple actions of inflammation and oxidative stress, has been implicated in risk for preterm birth (PTB). OBJECTIVES: This study aimed to determine the association of maternal Cu concentration during pregnancy with PTB risk and gestational duration in a large multicohort study including diverse populations. METHODS: Maternal plasma or serum samples of 10,449 singleton live births were obtained from 18 geographically diverse study cohorts. Maternal Cu concentrations were determined using inductively coupled plasma mass spectrometry. The associations of maternal Cu with PTB and gestational duration were analyzed using logistic and linear regressions for each cohort. The estimates were then combined using meta-analysis. Associations between maternal Cu and acute-phase reactants (APRs) and infection status were analyzed in 1239 samples from the Malawi cohort. RESULTS: The maternal prenatal Cu concentration in our study samples followed normal distribution with mean of 1.92 µg/mL and standard deviation of 0.43 µg/mL, and Cu concentrations increased with gestational age up to 20 wk. The random-effect meta-analysis across 18 cohorts revealed that 1 µg/mL increase in maternal Cu concentration was associated with higher risk of PTB with odds ratio of 1.30 (95% confidence interval [CI]: 1.08, 1.57) and shorter gestational duration of 1.64 d (95% CI: 0.56, 2.73). In the Malawi cohort, higher maternal Cu concentration, concentrations of multiple APRs, and infections (malaria and HIV) were correlated and associated with greater risk of PTB and shorter gestational duration. CONCLUSIONS: Our study supports robust negative association between maternal Cu and gestational duration and positive association with risk for PTB. Cu concentration was strongly correlated with APRs and infection status suggesting its potential role in inflammation, a pathway implicated in the mechanisms of PTB. Therefore, maternal Cu could be used as potential marker of integrated inflammatory pathways during pregnancy and risk for PTB.
Assuntos
Nascimento Prematuro , Gravidez , Feminino , Humanos , Recém-Nascido , Cobre , Idade Gestacional , Nascido Vivo , Inflamação , Fatores de RiscoRESUMO
Aspergillus flavipes, a slow growing pectinase producing ascomycete, was isolated from soil identified and characterised in the previously done preliminary studies. Optimisation studies revealed that Citrus peel--groundnut oil cake [CG] production media is the best media for production of high levels of pectinase up to 39 U/ml using wild strain of A. flavipes. Strain improvement of this isolated strain for enhancement of pectinase production using multistep mutagenesis procedure is the endeavour of this project. For this, the wild strain of A. flavipes was treated with both physical (UV irradiation) and chemical [Colchicine, Ethidium bromide, H2O2] mutagens to obtain Ist generation mutants. The obtained mutants were assayed and differentiated basing on pectinase productivity. The better pectinase producing strains were further subjected to multistep mutagenesis to attain stability in mutants. The goal of this project was achieved by obtaining the best pectinase secreting mutant, UV80 of 45 U/ml compared to wild strain and sister mutants. This fact was confirmed by quantitatively analysing 3rd generation mutants obtained after multistep mutagenesis.
Assuntos
Aspergillus/enzimologia , Aspergillus/genética , Poligalacturonase/biossíntese , Aspergillus/efeitos da radiação , MutagêneseRESUMO
The Laccases production efficiency was investigated by the wild fungal strains Trametes hirsuta by treating it with physical mutagen [ultraviolet radiation (UV) and X-rays] and chemical mutagens [Ethidium bromide, Colchicine and Hydrogen peroxide]. The present work aimed to apply mutagenesis for enhancement of the enzyme production. Effective changes were observed in the efficiency of enzyme production when treated with physical and chemical mutagens. The effect of X-rays showed a decrease in production with increasing exposure in T. hirsuta (Max. at 2 sec.). UV irradiation influenced the enzyme production with higher exposure time (8 minutes) but the maximum dosage led to inhibition in fungal growth and low enzyme production. Among the three chemical mutagens used, hydrogen peroxide was found to be having lethal effects to the fungi but a minimum concentration (2 µg/mL) was positively effecting enzyme production. Colchicine showed increase in enzyme production with increasing concentrations (Max. at 9 µg) and with Ethidium bromide, maximum enzyme production was observed at concentration of 7 µg/ mL. The study on morphological differences in wild and mutant shows that there was an improvement in strains of the white rot fungi.
Assuntos
Mutagênicos/farmacologia , Trametes/efeitos dos fármacos , Trametes/efeitos da radiação , Raios Ultravioleta , Raios X , Cruzamento , Colchicina/farmacologia , Etídio/farmacologia , Peróxido de Hidrogênio/farmacologia , Lacase/biossíntese , Mutagênese/efeitos dos fármacos , Mutagênese/efeitos da radiação , Trametes/genética , Trametes/metabolismoRESUMO
The present study reveals that a potent laccases producer Pycnoporus cinnabarinus produces higher quantity of laccases in the Coll et al. Medium (M1 medium) and Potato dextrose broth medium (M4 medium) containing agricultural waste ‘wheat bran’ (1%w/v) after a great comparative study among the five laccases production media namely Coll et al. medium (M1 medium), Olga et al. medium (M2 medium), Slomczynski medium (M3 medium), Potato dextrose broth (PDB) medium (M4 medium) and nutrient salt medium (M5 medium). There was a tremendous increase in laccases production with alternative carbon source. There was about 265.2% increase in laccases production in M1 Medium with wheat bran (126.99±2.046 U/ml/min) which further increased by 305% (140.78±1.118 U/ml/min) after the addition of dairy waste ‘Ghee residue’. In the presence of rice bran there was a reduction in laccase production, which however improved in the presence of Ghee residue by a good 63.8% (56.96±1.005 U/ml/min) compared to the M1 medium with glucose. Similarly in case of M4 medium, there was an increase in laccases production by 45.6% with wheat bran (89.46±1.861U/ml/min) and on addition of ghee residue it increased to about 95.6% (115.00±2.048U/ml/min). The beneficial effect of ghee residue was proved by comparative study on effect of other inducers namely copper sulfate, ammonium tartrate, ethanol and peptone. The maximum production was obtained in 9 days at pH 3.0 and temperature 35°C in potato dextrose broth medium (M4) with 1% w/v wheat bran and 2% w/v Ghee residue. The presence of phenolic compounds in the Ghee residue was found to be encouraging laccases production.
RESUMO
Pectinase is one of the most important commercially synthesised enzyme having its application in several industrial sectors like food and beverages, fruit clarifications etc. A.carbonarius has the capacity to produce Exo-pectinase 50 U/ml by submerged fermentation process as per the previous study. The present study describes the improvement of previously identified fungal strain Aspergillus carbonarius for enhancement of pectinase production by inducing mutations using physical and chemical mutagens. Aiming to increase the potentiality in pectinase production, the parental strain was treated for three times with four mutagens - UV irradiation, Colchicine, Hydrogen peroxide and Ethidium bromide to obtain mutants. Mutants were selected based on higher enzyme activity, improved growth rates and varied morphology with increased pectinase production. All the surviving mutants were assessed quantitatively after first mutagenic treatment. The stability of the best mutants was tested by repeating the exposures for two times to obtain 3rd generation mutants. These mutants were tested quantitatively to assess the pectinase production. Of all the best mutants E8 showed maximum activity producing 65U/ml pectinase enzyme compared to wild and sister mutants. The wild strain of A. carbonarius is a low pectinase producing organism as per literature. This strain was successfully mutated to increase the productivity rate to 1.8 fold in comparison to wild strain. This overproduction and strain stability may be due to repeated mutagenic treatments.