Characterization of pressurized hot water extracts of grape pomace: Chemical and biological antioxidant activity

2015 ◽  
Vol 171 ◽  
pp. 62-69 ◽  
Author(s):  
J.R. Vergara-Salinas ◽  
Mauricio Vergara ◽  
Claudia Altamirano ◽  
Álvaro Gonzalez ◽  
J.R. Pérez-Correa
2011 ◽  
pp. 279-288 ◽  
Author(s):  
Anita Klaus ◽  
Maja Kozarski ◽  
Miomir Niksic

Ganoderma lucidum (Leyss.:Fr.) Karst is one of the medicinal mushrooms, which possesses enviable antioxidant properties. Objective of this investigation was to evaluate antioxidant activity, reducing power, scavenging abilities on 1.1-diphenyl-2-picrylhydrazyl (DPPH) radicals and chelating effects on ferrous ions of hot water extracts obtained from carpophore and spores of this mushroom. Hot water extract from carpophore (Gl-I) showed high antioxidant activity of 85.7 ? 0.7%, at 10 mg/ml, while antioxidant activity of hot water extract from spores (Gl-Is) was 9.2 ? 0.3% at 10 mg/ml. Reducing power of Gl-I reached a plateau of 3.4 ? 0.1 at 20 mg/ml, and 0.3 ? 0.0 at 20 mg/ml for Gl-Is. At 10 mg/ml, scavenging ability on DPPH radicals of Gl-I increased to 96.8 ? 2.5%, whereas Gl-Is scavenged DPPH radicals by 69.6 ? 2.5% at 10 mg/ml. Gl-I chelated 81.6 ? 3.6 % of ferrous ions at 20 mg/ml, while the chelating effect of Gl-Is was 73.8 ? 1.7%. The antioxidative activities of hot water extracts from carpophore and spores of the mushroom G. lucidum were concentration dependent and increased with an increase in the concentration.


2022 ◽  
Vol 62 ◽  
pp. 102619
Author(s):  
Simon Gregersen ◽  
Margarita Pertseva ◽  
Paolo Marcatili ◽  
Susan Løvstad Holdt ◽  
Charlotte Jacobsen ◽  
...  

2018 ◽  
Vol 67 ◽  
pp. 03039
Author(s):  
Muhamad Sahlan ◽  
Charion Gibreth Hannes ◽  
Yanni Sudiyani ◽  
Heri Hermansyah ◽  
Anondho Wijanarko

One of the potential co-product of the manufacture of bioethanol made from oil palm empty fruit bunches are yeasts, which have antioxidant activity. Source of antioxidants can be obtained from vitamins and enzymes. In the characterization study of the antioxidant properties of yeast extract refers to a method performed by Xiong, by varying solvent and extraction time using hot water and ethanol 25%. From the variation of time and solvent extraction will be tested with the GSH content of alloxan method, to obtain the maximum concentration. The results show the isolation of amino acids with a hot solvent, at 15 minutes is better. These results are then carried out the characterization of amino acids with LCMS methods. An amino acid which has antioxidant activity is methionine, using the solvent water and tested methods of abortion LCMS and 3402.91 ppm ethanol with LCMS method implies 4137.002 ppm. Characterization of amino acids can then be used as a source of raw materials economic cosmetics worth selling.


2011 ◽  
Vol 39 (2) ◽  
pp. 117 ◽  
Author(s):  
Abd El-Moneim M.R. AFIFY ◽  
Emad A. SHALABY ◽  
Hossam Saad EL-BELTAGI

The antioxidant activity of water extracts (cold and hot) of six caffeine products were carried out. The extracts were screened for total polyphenol contents and antioxidant activity using DPPH, ABTS methods and reducing power method at 50 and 100 μg/ml after 15 min and 30 min using DPPH, ABTS BHA and Caffeine as standard compounds. The results indicated that, the hot water extracts for different caffeine products showed higher antioxidant activity than those of cold extracts and this activity was time and concentration dependent. In addition, the activity was higher against ABTS radical more than DPPH and reducing power methods. Also, there is a positive correlation between the antioxidant and reducing compounds presented in water extracts of different caffeine products. The results of HPLC showed that fresh tea leaves are rich in flavanol monomers known as catechins. The most abundant catechin derivatives in green tea are EGC, EGCG and GC. On the other hand EGCG and GC are major catechin derivative in different caffeine product except El-Fakher tea and Cacao. Generally, these beverages had high antioxidant capacities and total phenolic contents, and could be important dietary sources of antioxidant phenolic for prevention of diseases caused by oxidative stress.


Sign in / Sign up

Export Citation Format

Share Document