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Amy F. Fulcher, Thomas G. Ranney, James D. Burton, James F. Walgenbach, and David A. Danehower

Japanese beetles (JB), Popillia japonica Newman, are destructive, highly polyphagous herbivores that show a general preference for Rosaceous plants. Choice and nochoice feeding assays were conducted to determine the level of resistance among 10 taxa of Malus spp. Mill. Under no-choice conditions, M. baccata (L.) Borkh. `Jackii', M. × `Hargozam' Harvest Gold and M. transitoria (Balatin) Schneider `Schmitcutleaf' Golden Raindrops were highly resistant, with <2 cm2 leaf area consumed in 24 hours. M. × `Radiant' was highly susceptible, with 7.6 cm2 consumed, and the remaining six cultivars were intermediate. Under choice conditions, eight taxa were resistant with <10% defoliation, M. × `Red Splendor' was intermediate with 26%, and M. × `Radiant' was susceptible with 73% defoliation. Feeding responses to eight individual phenolics were tested in artificial diets over a range from 0 to 100 mm. Phloridzin, phloretin, naringenin, and catechin were all feeding deterrents, whereas quercetin and rutin were feeding stimulants. Chlorogenic acid stimulated feeding at low concentrations and deterred feeding at higher concentrations (i.e., a peak response). Kaempferol had no effect. Analysis of endogenous foliar phenolics showed considerable variation in concentrations among taxa. Stepwise multiple regression analysis identified phloridzin as the only endogenous phenolic that was significantly related to resistance under both choice and no-choice feeding conditions.

Open access

Martina Göttingerová, Michal Kumšta, and Tomáš Nečas

The nutritive quality of food and the aesthetic aspect contribute to the appearance of consumed food. In this study, apricot (Prunus armeniaca L.) flowers were used to determine vitamin C, total phenolic content, flavonoids, antioxidant capacity, carotenoids, anthocyanins, and amygdalin. Vitamin C content fluctuated between 24.97 and 47.35 mg·100 g–1 fresh weight (FW). The results show that all apricot flowers are a good source of phenolic compounds [404.08–768.45 mg gallic acid equivalent (GAE)/100 g FW] and flavonoids [198.76–538.11 mg catechin equivalent (CE)/100 g FW], and have good antioxidant capacity [414.66–1026.18 mg Trolox equivalent (TE)/100 g FW]. A high value of anthocyanins was measured in ‘Vestar’ (28.41 mg·100 g–1 FW) and also in ‘Blenheim’ (13.40 mg·100 g–1 FW). On the contrary, a low value was found in ‘Scout’ (1.60 mg·100 g–1 FW). The highest value of carotenoids was measured in ‘Blenheim’ (6.41 mg·100 g–1 FW), and the lowest in ‘Chuang Zhi Hong’ (1.36 mg·100 g–1 FW). Amygdalin content fluctuated between 110.81 and 419.78 mg·100 g–1 FW. Newly acquired information about the composition and nutritional value of edible flowers give reasons for their consumption.

Free access

Lavanya Reddivari and J. Creighton Miller Jr.

Antioxidants have been widely reported to play an important role in disease prevention. In addition to preventing cancer, stroke, heart diseases, and inflammation, they are also involved in immune surveillance. Since the per capita consumption of potatoes in the U.S. is about 137 lb, even moderate levels of antioxidants in this most important vegetable crop probably have an important human health benefit. About 75% to 80% of antioxidant activity in specialty potatoes is due to phenolics and carotenoids. The objectives of this investigation were to evaluate antioxidant activity and total phenolic and carotenoid content of specialty potato selections from the Texas Potato Variety Development Program, and to identify candidate compounds for cancer cell culture investigations. Potato tubers were also used to identify and quantify individual phenolics and carotenoids. Some 320 specialty selections were screened for antioxidant activity (AA), total phenolic content (TP) and carotenoid content (CC) using DPPH (2,2-Diphenyl-1-picrylhydrazyl), FCR (Folin-Ciocalteu Reagent) and colorimetric assays, respectively. After the initial screening, the top 10% were used for analysis of individual phenolics and carotenoids using HPLC. Wide variability for antioxidant activity, phenolic content, and carotenoid content was found among specialty potato selections, providing evidence for genetic control of theses traits. The specialty selection CO112F2-2P/P (purple flesh, purple skin) had the highest AA (832 μg trolox equivalents/g fw), TP (1553 μg chlorogenic acid equivalents/g fw) and CC (590 μg lutein equivalents/100 g fw). Chlorogenic acid (55% to 60%), caffeic acid (≈5%), gallic acid (18% to 20%), and catechin (18% to 20%) were found to be the most prevalent phenolic acids, and lutein and zeaxanthin were the most prominent carotenoids contributing to antioxidant activity. Gallic acid was identified as the candidate compound for use in cancer cell culture investigations.

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Young-Hwan Shin, Rui Yang, Yun-Long Shi, Xu-Min Li, Qiu-Yue Fu, Jian-Liang Lu, Jian-Hui Ye, Kai-Rong Wang, Shi-Cheng Ma, Xin-Qiang Zheng, and Yue-Rong Liang

light-sensitive albino tea plants was reviewed in the present article, including their morphological and chemical characteristics as well as molecular genetic mechanism of the albino induced by light. Chemical Composition Amino acids, catechins, and

Free access

Allan F. Brown, Gad G. Yousef, Ivette Guzman, Kranthi K. Chebrolu, Dennis J. Werner, Mike Parker, Ksenija Gasic, and Penelope Perkins-Veazie

neochlorogenic acid), flavan 3-ols (catechin, epicatechin, procyanidins), flavonols (quercetin 3-glucoside and 3-rutinoside), and ANC (cyanidin 3-glucoside and 3-rutinoside) ( Tomás-Barberán et al., 2001 ). The carotenoid profile of peach includes β - carotene, β

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Zhongshuai Gai, Yu Wang, Jutang Jiang, Hui Xie, Zhaotang Ding, Shibo Ding, and Hui Wang

/v) was added into each tube. The tubes were kept at room temperature for 60 min before absorbance at 765 nm was measured against water. Catechins were extracted from leaves as described previously ( Fan et al., 2015 ). The extracts of standards and

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Maedza V. Khathutshelo, Nkomo Mpumelelo, Ngezimana Wonder, and Mudau N. Fhatuwani

the flask was made up to volume with distilled water and thoroughly mixed. Absorbance of the reactants was read after 2 h at 760 nm using an ultraviolet-visible GENESYS 20 spectrophotometer (Germany). Catechin was used as a standard to formulate a

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Muttalip Gündoğdu, Tuncay Kan, and Mustafa Kenan Gecer

) . Chlorogenic acid (5-caffeoylquinic acid) is the dominant phenolic compound in apricots. The other phenolic compounds determined in apricots are neochlorogenic acid, caffeic acid, p-coumaric acid, ferulic acid, and their esters. (+)-Catechin and (−)-epicatechin

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Vlasta Cunja, Maja Mikulic-Petkovsek, Franci Stampar, and Valentina Schmitzer

of flavanols, phenolic acids, and their derivatives and hydrolysable tannins were determined in leaves of selected Rosa species and cultivars using MS n ( Table 2 ). Rosaceae can generally be characterized as a family rich in catechin and

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Ambani R. Mudau, Mpumelelo M. Nkomo, Puffy Soundy, Hintsa T. Araya, Wonder Ngezimana, and Fhatuwani N. Mudau

-visible spectrophotometer (Genesys™ 20; Cecil Instruments, Cambridge, UK). Catechin was used as standard to prepare a standard curve and results were expressed as milligrams catechin equivalents (CE) per 100 mg of samples on dry weight (DW) basis. Carotenoids analysis. The