et al., 2011 ). Cluster roots are characterized to release organic acid anions at a high level, and citrate is demonstrated to be the predominant acid released by cluster roots of tobacco under a K-deficient condition ( Wu et al., 2013 ). Collectively
Yongfeng Yang, Zhixiao Yang, Shizhou Yu and Hongli Chen
T. Casey Barickman, Dean A. Kopsell and Carl E. Sams
antioxidants linked to inhibiting cancers such as prostate ( Giovannucci et al., 1995 ), skin ( Gonzalez et al., 2003 ), and colon ( Slattery et al., 1999 ). Organic acids, such as malic and citric, and soluble sugars, such as fructose and glucose, contribute
Seth DeBolt, Renata Ristic, Patrick G. Iland and Christopher M. Ford
between light exposure and organic acid biosynthesis by both immature and mature berries has been reported ( DeBolt et al., 2006 , 2007 ; Kliewer and Schultz, 1964 ) and showed that full sun exposure resulted in maximum levels of tartaric acid formation
Yifei Wang, Stephanie K. Fong, Ajay P. Singh, Nicholi Vorsa and Jennifer Johnson-Cicalese
, 2014 ; Horvat and Senter, 1985 ), blueberries also contain different organic acids, including citric, quinic, malic, and succinic acids that contribute to their unique flavor ( Ehlenfeldt et al., 1994 ). Moreover, they are also known for the rich
Yu Wang, Haobo Yang, Shuai Zhong, Xin Liu, Tong Li and Chengwen Zong
China is 7 million kilograms, which is primarily used for producing wine, juice, jam, and preserved products ( Zong et al., 2011 ). Anthocyanins, flavonoids, phenols, and organic acids in V. uliginosum fruit show various biological properties
Tripti Vashisth, Mercy A. Olmstead, James Olmstead and Thomas A. Colquhoun
to yield high quality, nutritious fruit, in addition to optimum production. Therefore, in the present study, we focused on the impact of different rates of N fertilization on fruit quality including organic acid, TSS, TA, total phenolic content
Mark K. Ehlenfeldt, Filmore I. Meredith and James R. Ballington
The fruit of six highbush (Vaccinium corymbosum L.) cultivars and eight rabbiteye (V. ashei Reade) cultivars and selections were evaluated by high-performance liquid chromatography for levels of the commonly found organic acids, citric, malic, succinic, and quinic. The two cultivar groups possessed distinctive patterns of relative organic acid proportions that could unambiguously separate pure rabbiteye and highbush clones in a principal component analysis. Highbush clones were characterized by high citric acid content, with percentages averaging 75% (range 38% to 90%). Succinic acid was the second most plentiful acid, averaging 17%. In contrast, rabbiteye cultivars and selections contained 10% citric acid, and no clone had >22%. Succinic acid and malic acid were found in greater quantities than in highbush, averaging 50% and 34%, respectively. Analysis of the fruit of seven albino-fruited highbush selections exhibited a profile similar to standard highbush cultivars, but with a citric acid average of <50%, and proportionally greater amounts of succinic and quinic acids. Given the differences in sensory quality of these four acids, it is likely that acid partitioning patterns can largely account for some of the perceived flavor differences between rabbiteye and highbush blueberries. Because several current breeding efforts involve hybridization between highbush and rabbiteye blueberries, a consideration of acid composition of breeding parents maybe worthwhile.
Franco Famiani and Robert P. Walker
ripening is mostly a result of the accumulation of fructose and glucose ( Kafkas et al., 2006 ; Perkins-Veazie et al., 2000 ; Wrolstad et al., 1980 ). Isocitric, lactoisocitric, and malic acids make up the bulk of organic acids in blackberry; however, the
Ki-Cheol Son, Ray F. Severson, Maurice E. Snook and Stanley J. Kays
Methanol extracts of external (outer 3 mm) and interior root tissue of four sweetpotato [Ipomoea batatas (L.) Lam.] cultivars (`Centennial', `Jewel', `Regal', and `Resisto') having different levels of susceptibility to the sweetpotato weevil [Cylas formicarius elegantulus Summer] were analyzed for simple carbohydrates (fructose, glucose, sucrose, inositol) and organic acids (malic, citric, quinic) by gas chromatography and for phenolics (caffeic acid, caffeoylquinic acids, rutin) by high-performance liquid chromatography. There were significant differences among cultivars in the concentrations of total sugars and phenolics in the external tissue (P < 0.05). In addition, the distribution of carbohydrates, organic acids, and chlorogenic acid [3-O-caffeoylquinic acid] differed between external and interior tissues. Sucrose was the major water-soluble carbohydrate in all cultivars. With the exception of malic acid, the concentration of carbohydrates, organic acids, and phenolics did not correlate with cultivar susceptibility to the sweetpotato weevil.
Michael Knee and Fernando L. Finger
Tomato (Lycopersicon esculentum Mill., cv. Ohio 7814) fruits were harvested weekly following flowering to relate changes in NADP+-malic enzyme (NADP-ME) activity and major organic acids (malate and citrate) to fruit development. Specific activity of NADP-ME and fresh weight concentrations of the acids reached maximal levels at the mature-green stage. During ripening, a decline in malate concentration was followed by decreases in NADP-ME activity and citrate concentration. Activity of NADP-ME and organic acid concentrations were highest in the locular gel, but activity also occurred in tomato leaves, stems, and roots. The data do not exclude a role for NADP-ME in the metabolism of organic acids during fruit ripening. However, it is also possible that the enzyme is involved in cytoplasmic pH regulation.