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Concept: Anthocyanin


Shelf life is an important quality trait for many fruit, including tomatoes. We report that enrichment of anthocyanin, a natural pigment, in tomatoes can significantly extend shelf life. Processes late in ripening are suppressed by anthocyanin accumulation, and susceptibility to Botrytis cinerea, one of the most important postharvest pathogens, is reduced in purple tomato fruit. We show that reduced susceptibility to B. cinerea is dependent specifically on the accumulation of anthocyanins, which alter the spreading of the ROS burst during infection. The increased antioxidant capacity of purple fruit likely slows the processes of overripening. Enhancing the levels of natural antioxidants in tomato provides a novel strategy for extending shelf life by genetic engineering or conventional breeding.

Concepts: Bacteria, Antioxidant, Vitamin C, Fruit, Tomato, Ethylene, Anthocyanin, Raspberry


Cytochromes P450 play important roles in biosynthesis of flavonoids and their coloured class of compounds, anthocyanins, both of which are major floral pigments. The number of hydroxyl groups on the B-ring of anthocyanidins (the chromophores and precursors of anthocyanins) impact the anthocyanin colour, the more the bluer. The hydroxylation pattern is determined by two cytochromes P450, flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H) and thus they play a crucial role in the determination of flower colour. F3'H and F3'5'H mostly belong to CYP75B and CYP75A, respectively, except for the F3'5'Hs in Compositae that were derived from gene duplication of CYP75B and neofunctionalization. Roses and carnations lack blue/violet flower colours owing to the deficiency of F3'5'H and therefore lack the B-ring-trihydroxylated anthocyanins based upon delphinidin. Successful redirection of the anthocyanin biosynthesis pathway to delphinidin was achieved by expressing F3'5'H coding regions resulting in carnations and roses with novel blue hues that have been commercialized. Suppression of F3'5'H and F3'H in delphinidin-producing plants reduced the number of hydroxyl groups on the anthocyanidin B-ring resulting in the production of monohydroxylated anthocyanins based on pelargonidin with a shift in flower colour to orange/red. Pelargonidin biosynthesis is enhanced by additional expression of a dihydroflavonol 4-reductase that can use the monohydroxylated dihydrokaempferol (the pelargonidin precursor). Flavone synthase II (FNSII)-catalysing flavone biosynthesis from flavanones is also a P450 (CYP93B) and contributes to flower colour, because flavones act as co-pigments to anthocyanins and can cause blueing and darkening of colour. However, transgenic plants expression of a FNSII gene yielded paler flowers owing to a reduction of anthocyanins because flavanones are precursors of anthocyanins and flavones.

Concepts: DNA, Color, Flavonoid, Pigments, Flower, Hue, Anthocyanin, Anthocyanidin


In the present study, the production of a reduced-sugar pomegranate juice jelly supplemented with an aqueous extract of pomegranate peel (PE) is described. Influence of different carbohydrate polymers (guar (G), xanthan (X) and tragacanth (T) gums) on rheological properties was studied. Combination GXT presented the most similar rheological behaviour to commercial jelly. Jelly (J) and jelly with PE (JE) were stored at 4°C over an 8week period for physical, chemical, antioxidant, microbiological and sensory analysis. J and JE showed similar values for °Brix, colour and Aw, though the pH of JE was lower than J. Thiol and phenolic compounds were higher in JE than in J. Antioxidant activity (radical scavenging activity and autoxidation of linoleic acid) was higher in JE than in J at 0weeks, and were decreasing with time. Pomegranate juice with additives was generally less accepted than J and JE.

Concepts: Present, Time, Antioxidant, PH, Resveratrol, Olive oil, Anthocyanin, Pomegranate


Different dehydrated waste grape skins from the juice industry were added into aged and young red wines as an innovative way of compensating for colour loss before bottling. After addition of grape skins, colour intensity of wines increased a mean 11% and a maximum of 31% with predominance of the red component. Total polyphenols mean increase was 10% with a maximum value of 20%. Analysis of low molecular weight phenolic compounds by HPLC-DAD showed a significant (p<0.05) content increase of the bioactive compounds gallic acid, (+)-catechin, (-)-epicatechin, and (E)-resveratrol. Anthocyanins content also increased at an average of 50mg/l. The volatile profile of wines analysed by SBSE-GC-MS was only moderately influenced by the treatments. Mixtures of dehydrated waste grape skins were useful to improve the colour and polyphenol profile of red wines, considering them a useful tool for correcting colour loss before bottling.

Concepts: Catechin, Resveratrol, Wine, Tannin, Polyphenol, Fermentation, Anthocyanin, Polyphenols


The total phenolic content (TFC), total flavonoid content (TFC), antioxidant activity, and polyphenols composition of rabbiteye blueberry fruit polyphenols (BBFPs) extract, rabbiteye blueberry pomace polyphenols (BBPPs) extract, and rabbiteye blueberry leaves polyphenols (BBLPs) extract were investigated. The highest TPC and TFC were found in the BBLPs extract, followed by the BBPPs and BBFPs extracts. The BBLPs extract exhibited the highest antioxidant activity according to five antioxidant methods. All the three samples exhibited significantly higher antioxidant activity than the positive control rutin. HPLC-DAD-MSn analysis showed that the BBFPs extract contained nine different anthocyanins, while the BBPPs extract contained only four of them. In addition, four caffeoylquinic acids, quercetin, and its three derivatives were detected in the BBLPs extract. The results indicated that the fruits, pomace, and leaves of rabbiteye blueberry were good sources of polyphenols and natural antioxidants. These could be useful as functional food ingredient beneficial to human health.

Concepts: Nutrition, Antioxidant, Quercetin, Flavonoid, Resveratrol, Anthocyanin, Vaccinium, Blueberry


Understanding the factors that contribute to the degradation of bioactive compounds during microwave treatment is meaningful for the practical application of this novel technology. The influence of microwave power, energy density, temperature, pH value and the initial concentration of anthocyanin (Acys) on the degradation behavior of malvidin-3-glucoside (Mv-3-glu) and malvidin- 3,5- diglucoside (Mv-3,5-diglu) were investigated in this study. Results showed that the degradations of the both Acys were accelerated with the increase of power, microwave energy density, temperature, pH value and the initial concentration of Acys. The degradation process of the both Acys followed the first-order kinetics model (R2 > 0.94), whereas the relationship between Acys degradation and energy density fitted to the Logistic model well (R2 > 0.98). In addition, Mv-3-glu was more susceptible to the microwave treatment than Mv-3,5-diglu. Compared with the heating at 98 ºC ± 2 ºC water bath, the both Acys degraded more rapidly under microwave treatment at 100 ºC, indicating the occurrence of microwave effect. The results can provide a guide 20 for the scientific application of microwave treatment.

Concepts: Energy, Fundamental physics concepts, Density, Electromagnetic radiation, Temperature, Heat, Land degradation, Anthocyanin


Yan73 is a ‘teinturier’ red wine variety cultivated in China and widely used in winemaking to strengthen red wine colour. The objective of this study was to evaluate the effect of exogenous abscisic acid (ABA) applied to the grapevine cluster on the antioxidant capacity and phenolic content of the wine made from Yan73. Two hundred mg/l ABA was applied on Yan73 grapevine cluster during veraison. As they mature, these ABA-treated and untreated grape berries were transformed into wines, respectively, and the phenolic content and antioxidant capacity of these wines were compared. The results showed that phenolic content (total phenolics, tannins, flavonoids and anthocyanins) and antioxidant capacity were higher in the wine produced with ABA-treated Yan73 grapes than those in the wine from untreated grapes. Compared to Cabernet Sauvignon wine, Yan73 wine had higher phenolic content and stronger antioxidant capacity. These strongly suggest that exogenously applied ABA to Yan73 grapes can enhance phenolic content and antioxidant capacity of its wine, and Yan73 wine has the higher utilization value and potential for development.

Concepts: Vitis vinifera, Resveratrol, Wine, Oenology, Polyphenol, Grape, Cabernet Sauvignon, Anthocyanin


Grape anthocyanins reacted with diacetyl, a secondary metabolite of microorganisms involved in winemaking, to form 10-acetyl-pyranoanthocyanins, a type of anthocyanin-derived pigments similar to other vitisin-type pyranoanthocyanins found in red wines. The structures of 10-acetyl-pyranomalvidin-3-β-O-glucoside and 10-acetyl-pyranopeonidin-3-β-O-glucoside were confirmed by spectroscopic methods (UV-vis, MS/MS, and NMR) after their synthesis and isolation. In contrast to other vitisin-type pyranoanthocyanins, the newly described 10-acetyl-pyranoanthocyanins exhibited differentiated color-related properties. They showed an important tendency to occur as colorless hemiacetals at C-10 under wine pH conditions, while co-occurrence of flavylium cation and quinoidal base yield a broad visible absorbance band around 510-520 nm. Moreover, they easily reacted with bisulfite in acidic aqueous solution (pH 2.0), but the expected bleaching was not observed. Bisulfite bonded to the carbonyl of 10-acetyl substituent instead the expected C-10 position of the pyranoanthocyanin core, thus giving rise to a red pigment hypsochromically shifted towards orangish nuances (maximum absorbances at 487-491 nm).

Concepts: Spectroscopy, Chemistry, Color, Vermilion, Wine, Oenology, Base, Anthocyanin


Some fruits and their anthocyanin-rich extracts have been reported to exhibit chemopreventive activity in the oral cavity. Insights regarding oral metabolism of anthocyanins remain limited. Anthocyanin-rich extracts from blueberry, chokeberry, black raspberry, red grape, and strawberry were incubated ex vivo with human saliva from 14 healthy subjects. All anthocyanins were partially degraded in saliva. Degradation of chokeberry anthocyanins in saliva was temperature dependent and decreased by heating saliva to 80 °C and after removal of cells. Glycosides of delphinidin and petunidin were more susceptible to degradation than those of cyanidin, pelargonidin, peonidin and malvidin in both intact and artificial saliva. Stability of di- and tri-saccharide conjugates of anthocyanidins slightly, but significantly, exceeded that of monosaccharide compounds. Ex vivo degradation of anthocyanins in saliva was significantly decreased after oral rinsing with antibacterial chlorhexidine. These results suggest that anthocyanin degradation in the mouth is structure-dependent and largely mediated by oral microbiota.

Concepts: Mouth, Fruit, Anthocyanin, Raspberry, Rubus occidentalis, Anthocyanidin, Petunidin, Anthocyanidins


Gomphrena globosaL. is a popular edible plant used as food colourant and in traditional medicine. In this work, 24 phenolic compounds and eight betacyanins were determined by HPLC-DAD in three different extracts of G. globosa inflorescences. The decoction presented the highest amount of phenolic compounds, kaempferol-3-O-(6-rhamnosyl)hexoside plus kaempferol-3-O-hexoside being the main compounds. The rich betacyanins extract showed isogomphrenin III and gomphrenin III as major metabolites. Decreases in the nitric oxide amounts were observed in LPS-stimulated RAW 264.7 cells. In vitro scavenging micro assays against several reactive species revealed a great antioxidant capacity, particularly against superoxide radical. In general, the best results were obtained with decoction. Some relationships between activity and composition were established. The data provide evidence of the G. globosa inflorescences potential as a source of anti-inflammatory compounds, with relevance for the treatment of acute or chronic inflammatory conditions, and health-promoting antioxidants for use by both food and pharmaceutical industries.

Concepts: Nutrition, Antioxidant, Superoxide dismutase, Nitric oxide, Resveratrol, Anthocyanin, Amaranthaceae, Gomphrena globosa