Comparative study of sugars, organic acids and trans-resveratrol in red and white grapes grown in Denizli region, Turkey

Grape berry ripening includes a broad range of physical and biochemical processes. In this study, compare the changes in organic acid, sugar and trans-resveratrol content during at four different ripening stages (lag phase, veraison, maturity and late harvest) between red (Çalkarasi and Shiraz) and white (Sultana and Round Seedless) grapes grown in Denizli region were investigated. Analysis was carried out using the high performance liquid chromatography-diode array detector (HPLC-DAD). Glucose and fructose content was increased between lag phase stages and late harvest stages. Tartaric and malic acid content of all cultivars decreased throughout the maturation period. A continuous decrease in trans-resveratrol content in all varieties was observed during ripening. © 2015, Chemical Publishing Co. All rights reserved

Zeytinyağı Üretiminde Verim Artırıcı Maddelerin Kullanımının Bazı Kalite Özellikleri Üzerine Etkileri

Bu çalışmada; zeytinyağı üretiminde verim artttırıcı maddelerin kullanımının yağ verimi ve yağın kalitesi üzerindeki etkileri incelenmiştir. Verim artırıcı maddeler olarak naturel mikronize talk, enzim ve naturel mikronize talk-enzim kombinasyonu kullanılmıştır. Naturel mikronize talk, % 1, % 1.5, ve % 2, enzim 0.02 ml enzim/ 100 g zeytin hamuru ve naturel mikronize talk-enzim kombinasyonu; en uygun naturel mikronize talk oranı olarak saptanan %1’e % 0.01, %0.015 ve % 0.02 oranlarında enzim ilave edilerek uygulanmıştır. Denemeler Abencor sisteminde, Ayvalık ve Memecik zeytin çeşitlerinde gerçekleştirilmiştir. Verim arttırıcı maddelerin her iki zeytin çeşidinde de yağ verimi ve kalitesi üzerine etkileri incelenmiştir. Zeytin çeşitlerinin; olgunlaşma indeksi, yağ ve su içerikleri, zeytinyağı örneklerinin ise; serbest asitlik değerleri, 232 ve 270 nm’deki U.V. absorbans değerleri ve toplam polifenol içerikleri saptanmıştır.Elde edilen sonuçlar ; %1 naturel mikronize talk kullanımının verim artışı açısından enzim kullanımdan daha etkili olduğunu ve yağın kalite kriterlerinde olumsuz bir değişiklik oluşturmadığını ortaya koymaktadır

Physicochemical and bioactive properties of edible methylcellulose films containing Rheum ribes L. extract

WOS: 000493283100031PubMed: 31639581Methylcellulose (MC) polymer was used to prepare the edible films. Then, the Rheum ribes L. ethanol extract (RE) was added to the films in order to act as a natural antimicrobial agent. All the methylcellulose films were characterized for bioactivity and the physicochemical analysis were carried out to define functional group interactions between the polymer and RE. The strongest antimicrobial effect was obtained with MC films enriched with 2% (w/w) RE against to Listeria monocytogenes with 20.3 +/- 2.5 mm zone diameter. In the presence of RE, the tensile strength of film decreased, whereas the extract concentration significantly increased. The elongation at break and the water vapor permeability (WVP) values of the films were found to have decreased significantly in parallel with the increase in RE content. Moreover, the increase in the concentration of RE caused an increment in the hydrophilic properties, especially contact angle values of the films

DPPH Radical Scavenging, Phenolic and Antimicrobial Activity of Momordica charantia and Rheum ribes

Guder, Aytac/0000-0002-1190-8749WOS: 000438848100055In this study was to investigate total phenolic contents, 1, 1-Diphenyl-2-picrylhydrazyl (DPPH center dot), antimicrobial and antifungal activity by using different extract of Momordica charantia and Rheum ribes. The extraction applied to different part of Momordica charantia as husk and fruit and Rheum ribes as blossom and stem. Three different were used extraction solvent such as hexane, ethanol and water/acetic acid (1%). The highest radical scavenging activity was observed in ethanol extract of rhubarb blossom, acetic acid (1%) extract of rhubarb showed remarkable radical scavenging activity and the highest phenolic content value was observed acetic acid (1%) extracts of bitter melon. The highest antimicrobial efficacy against C. albicans was provided by the ethanol extract of the part of crust of Momordica charantia and acetic acid-water extraction of the blossom of Rheum ribes.Giresun UniversityGiresun University [FEN-BAP-A-160317-45]This study was supported by Giresun University (FEN-BAP-A-160317-45) Scientific Research Project