Optimisation of antioxidant activity of grape cane extracts using response surface methodology

Karacabey, Erkan
Mazza, Giuseppe
Solid-liquid extraction and response surface methodology were used to optimise conditions for the antioxidant activity of grape cane extracts. The independent processing variables were ethanol concentration, temperature and solvent to solid ratio. Ethanol concentration and temperature significantly affected antioxidant activity measured by the Trolox equivalent antioxidant capacity (TEAC) assay and the oxygen radical absorbance capacity using fluorescein (ORAC(FL)) method (p 0.05). Antioxidant activity of the extracts, determined by the TEAC assay, varied from 85.6 to 238.6 mu mol Trolox equivalents/g of dry sample. ORAC(FL) values ranged from 308.4 to 1302.7 mu mol Trolox equivalents/g of dry sample. Ethanol concentrations of 40.4% and 55.4% were optimal for the highest antioxidant activities measured by the TEAC assay and the ORAC(FL) method, respectively. The optimal temperature was 83.6 degrees C. Antioxidant activity correlates with total phenolic content of extracts. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.


Optimising clarification of carrot juice by bacterial crude pectinase
Uzuner, Sibel; Çekmecelioğlu, Deniz (2015-12-01)
This study was undertaken to search for potential use of crude bacterial pectinase enzyme produced from Bacillus subtilis grown on hazelnut shell hydrolysate in clarification of carrot juice and to optimize the enzyme load, pH and time using the Box-Behnken response surface methodology (RSM). The carrot juice was treated with the crude pectinase enzyme (5.60 U mL(-1)) at different concentrations (0.1-0.5%), pH (4-7), and time (2-6 h). The obtained enzyme was also compared with commercial fungal pectinase at...
Optimization and Comparison of High-Pressure-Assisted Extraction of Phenolic Compounds from Olive Pomace
Okur, İlhami; Öztop, Halil Mecit; Alpas, Hami (2022-12-16)
In this study, it was aimed to find the optimum condition for extraction of phenolic compounds from olive pomace by using high-pressure-assisted extraction (HPAE). In this method, different pressure parameters (300-500 MPa), times (5-15 min), and ethanol concentrations (50-90% v/v) were used. According to Box-Behnken design, 15 experimental runs were performed to find the optimum condition of total phenolic and oleuropein contents. Also, the optimum HPAE condition was compared with that of classical solvent...
Enzymatic hydrolysis of fruit peels and other lignocellulosic biomass as a source of sugar for fermentation
Poçan, Pelin; Öztop, Halil Mecit; Hamamcı, Haluk; Department of Food Engineering (2015)
In this study, enzymatic hydrolysis of corn cobs, orange and pomegranate peels were evaluated. For the hydrolysis of corn cobs, effect of alkaline pretreatment was examined and it was found that glucose and reducing sugar yield (%) for the pretreated corn cobs increased from 7% to 21.5% and 14% to 33.6% respectively. Effect of cellobiase loading on hydrolysis efficiency was also investigated. It was observed that when cellobiase was added to hydrolysate in addition to cellulase, glucose and total reducing s...
Comparison of antioxidant enzyme activities and DNA damage in chickpea (Cicer arietinum L.) genotypes exposed to vanadium
Imtiaz, Muhammad; Mushtaq, Muhammad Adnan; Rizwan, Muhammad Shahid; Arif, Muhammad Saleem; Yousaf, Balal; Ashraf, Muhammad; Xiong Shuanglian, Xiong Shuanglian; Rizwan, Muhammad; Mehmood, Sajid; Tu, Shuxin (2016-10-01)
The present study was done to elucidate the effects of vanadium (V) on photosynthetic pigments, membrane damage, antioxidant enzymes, protein, and deoxyribonucleic acid (DNA) integrity in the following chickpea genotypes: C-44 (tolerant) and Balkasar (sensitive). Changes in these parameters were strikingly dependent on levels of V, at 60 and 120 mg V L-1 induced DNA damage in Balkasar only, while photosynthetic pigments and protein were decreased from 15 to 120 mg V L-1 and membrane was also damaged. It was...
Proteomics of phanerochaete chrysosporium under heavy metal stress
Yıldırım, Volkan; Özcengiz, Gülay; Department of Biology (2014)
In this study, time-dependent heavy metal response of the white rot fungus P. chrysosporium was analyzed by using 2D-PAGE-MS for soluble cytosolic fraction and GeLC-MS approach for membrane enriched fraction. After the 2D-PAGE-MS analysis, a total of 123 protein spots were detected as differentially expressed for Cu-exposed samples and 89 of them were identifed. Further analysis revealed that the 89 protein spots are the products of the 58 distinct ORFs. Overall, strongly up-regulated proteins included (i) ...
Citation Formats
E. Karacabey and G. Mazza, “Optimisation of antioxidant activity of grape cane extracts using response surface methodology,” FOOD CHEMISTRY, pp. 343–348, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/64535.