The effects of hydrogen peroxide, gallic acid and resveratrol on growth and catalase production of aspergillus fumigatus

Download

index.pdf

Date

2008

Author

Doğan, Tunca

Metadata

Show full item record

Item Usage Stats

207
views

83
downloads

The aim of this study was to analyze the effect of hydrogen peroxide and selected phenolic compounds on growth and catalase production of Aspergillus fumigatus. As a result of growing A. fumigatus at different temperatures it was observed that, growth and catalase production of this species were highest at 37 °C. Catalase production was highest in the presence of 1 mM H2O2, yielding a significant 3 fold increase with respect to the control. Biomass was also increased by 1,44 fold with respect to the control sample. H2O2 increased catalase production possibly by inducing oxidative stress as biomass production significantly increased after the depletion of H2O2. Both gallic acid and trans-resveratrol significantly enhanced biomass generation of A. fumigatus (1,17 fold increase at 10 mM gallic acid and 1,45 fold increase at 3 mM resveratrol with respect to controls) and decreased extracellular catalase production (4,33 fold at 25 mM gallic acid and 16,7 fold decrease at 3 mM resveratrol with respect to controls) especially in the first 5 or 6 days of the cultivation where the anti-oxidant activity of the compounds were possibly at their maximum. A sudden and significant rise was observed in extracellular catalase activity between 5th and 7th days of the cultivation in phenolic compound applied samples, possibly owing to the depletion of the antioxidant activity of gallic acid and resveratrol followed by fungal cells’ response to a sudden increase of oxidative stress by boosting catalase production.

Subject Keywords

Food engineering.

URI

http://etd.lib.metu.edu.tr/upload/12609281/index.pdf
https://hdl.handle.net/11511/17513

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Influence of alcohols on citric acid production by Aspergillus niger A-9 entrapped in polyacrylamide gels Yaykasli, KO; Demirel, G; Yasar, A (Elsevier BV, 2005-10-01) In this study, the production of citric acid has been achieved by using Aspergillus niger conidiaspores, entrapped in polyacrylamide gels, and the factors that affect this production have been investigated. On citric acid production the effect of starting sucrose concentration (100-180 g/l), the initial nitrogen concentration (0-0.3 g/l), the effect of the methanol concentration in 100ml feeding medium (0-6 ml), and finally the effect of ethanol concentration (0-6 ml) in 100 ml feeding medium were studied a...
The impact of UV-C irradiation on spoilage microorganisms and colour of orange juice Taze, Bengi Hakguder; Unluturk, Sevcan; Buzrul, Sencer; Alpas, Hami (Springer Science and Business Media LLC, 2015-02-01) The effect of UV-C irradiation on inactivation of spoilage microorganisms and colour of freshly squeezed orange juice were investigated. Orange juice samples were intentionally fermented in order to increase the natural microflora which were mostly composed of yeasts and then exposed to UV-C irradiation at an intensity level of 1.32 mW/cm(2) and sample depth of 0.153 cm for several exposure times by using a collimated beam apparatus. Applied UV dose was in the range of 0 and 108.42 mJ/cm(2). Resistance of y...
Microwave assisted extraction of phenolic compounds from tomato and sour cherry pomaces Şimşek, Meriç; Şümnü, Servet Gülüm; Department of Food Engineering (2010) The objective of this study was to compare microwave assisted extraction (MAE) and conventional extraction methods for the extraction of total phenolic compounds (TPC) from tomato and sour cherry pomace. Antiradical efficiency (AE) of the extracts and also the concentration of phenolic compounds were determined. In MAE, the effects of microwave power (400 and 700 W), solvent type (water, ethanol and ethanol-water mixture at 1:1 v/v), extraction time (8-20 min) and solvent to solid ratio (10, 20 and 30 ml/g)...
THE EFFECT OF DEPECTINIZATION AND CLARIFICATION ON THE FILTRATION OF SOUR CHERRY JUICE Şahin, Serpil (Elsevier BV, 1993-01-01) Filtration rate and resistance are affected by the operations prior to filtration in fruit juice production lines. In this research, the effects of depectinization and clarification on filtration resistance and rate were evaluated. Filtration studies on raw juice, depectinized juice and depectinized plus clarified juice were compared It was observed that pretreatments reduce the resistance considerably.
Investigation of sensory and instrumental methods to predict shelf-life of jelly gums Tireki, Suzan; Şümnü, Servet Gülüm; Şahin, Serpil; Department of Food Engineering (2017) The main aim of this study was to correlate sensorial changes with instrumental techniques to predict shelf life during storage of jelly gums. Effects of glucose syrup:sucrose ratio, starch and gelatine content on quality and sensorial properties of jellies were investigated. Glucose syrup: sucrose ratio, starch and gelatine contents affected hardness significantly. Moisture content, water activity, total soluble solids, pH, springiness and gumminess was influenced by only glucose syrup:sucrose ratio. Moist...

Citation Formats

T. Doğan, “The effects of hydrogen peroxide, gallic acid and resveratrol on growth and catalase production of aspergillus fumigatus,” M.S. - Master of Science, Middle East Technical University, 2008.