Effects of Different Light Wavelengths on Fruit Quality and Gene Expression of Anthocyanin Biosynthesis in Blueberry (Vaccinium corymbosm).

Different light wavelengths display diverse effects on fruit quality formation and anthocyanin biosynthesis. Blueberry is a kind of fruit rich in anthocyanin with important economic and nutritional values. This study explored the effects of different light wavelengths (white (W), red (R), blue (B) and yellow (Y)) on fruit quality and gene expression of anthocyanin biosynthesis in blueberry. We found that the B and W treatments attained the maximum values of fruit width, fruit height and fruit weight in blueberry fruits. The R treatment attained the maximum activities of superoxide dismutase (SOD) and peroxidase (POD), and the Y treatment displayed the maximum contents of ascorbic acid (AsA), glutathione (GSH) and total phenol in fruits, thus improving blueberry-fruit antioxidant capacity. Interestingly, there were differences in the solidity-acid ratio of fruit under different light-wavelength treatments. Moreover, blue light could significantly improve the expression levels of anthocyanin biosynthesis genes and anthocyanin content in fruits. Correlation and principal component analysis showed that total acid content and antioxidant enzymes were significantly negatively correlated with anthocyanin content in blueberry fruits. These results provide new insights for the application of light wavelength to improve blueberry fruit quality and anthocyanin content.

Hierarchical regulation of MYBPA1 by anthocyanin- and proanthocyanidin-related MYB proteins is conserved in Vaccinium species.

Members of the Vaccinium genus bear fruits rich in anthocyanins, a class of red-purple flavonoid pigments that provide human health benefits, although the localization and concentrations of anthocyanins differ between species: blueberry (V. corymbosum) has white flesh, while bilberry (V. myrtillus) has red flesh. Comparative transcriptomics between blueberry and bilberry revealed that MYBPA1.1 and MYBA1 strongly correlated with the presence of anthocyanins, but were absent or weakly expressed in blueberry flesh. MYBPA1.1 had a biphasic expression profile, correlating with both proanthocyanidin biosynthesis early during fruit development and anthocyanin biosynthesis during berry ripening. MYBPA1.1 was unable to induce anthocyanin or proanthocyanidin accumulation in Nicotiana benthamiana, but activated promoters of flavonoid biosynthesis genes. The MYBPA1.1 promoter is directly activated by MYBA1 and MYBPA2 proteins, which regulate anthocyanins and proanthocyanidins, respectively. Our findings suggest that the lack of VcMYBA1 expression in blueberry flesh results in an absence of VcMYBPA1.1 expression, which are both required for anthocyanin regulation. In contrast, VmMYBA1 is well expressed in bilberry flesh, up-regulating VmMYBPA1.1, allowing coordinated regulation of flavonoid biosynthesis genes and anthocyanin accumulation. The hierarchal model described here for Vaccinium may also occur in a wider group of plants as a means to co-regulate different branches of the flavonoid pathway.

Effects of high hydrostatic pressure and thermal processing on anthocyanin content, polyphenol oxidase and ß-glucosidase activities, color, and antioxidant activities of blueberry (Vaccinium Spp.) puree.

Thermal processing (TP) and high hydrostatic pressure (HHP) are two important puree processing methods. In this study, the polyphenol oxidase (PPO) and ß-glucosidase activities, chromatic values, peroxide radical scavenging capacities (PSCs), cellular antioxidant activities (CAAs), and anthocyanin profiles were evaluated in blueberry puree following TP and HHP treatments. Nine anthocyanins were identified and cyanidin glycosides were the most abundant compounds in the blueberry puree sample. Petunidin-3-O-arabinoside, malvidin-3-O-galactoside, and malvidin-3-O-glucoside concentrations increased at temperatures of 70-90 °C (TP) and a pressure of 300 MPa (HHP). The highest total anthocyanin concentration (503.5 µg/mL) and PSC (13.45 µg VCE/mL) were observed following the TP (90 °C) treatment. Furthermore, a positive correlation was observed between the anthocyanin content and PSC (R2 = 0.655, P < 0.05). Finally, HHP treatment resulted in better puree color retention than TP treatment. The results of this study could provide valuable information for optimizing the processing methods for anthocyanin-rich products.

Immobilization of Andean berry (Vaccinium meridionale) polyphenols on nanocellulose isolated from banana residues: A natural food additive with antioxidant properties.

Nanocellulose obtained from banana rachis (NCBR) was loaded (through simple impregnation) with a polyphenolic-rich extract (PRE) of Andean berries (Vaccinium meridionale). The adsorption/desorption of polyphenols onto NCBR and the thermal stability and antioxidant activity of the polyphenolic-NCBR nanocomplex (NCX) was studied. Thermodynamic properties (ΔH°ads, ΔS°ads and ΔG°ads) showed that polyphenols interact with NCBR by physisorption through a spontaneous and exothermic process. The NCX kept the original color of PRE (magenta) and released polyphenols in aqueous medium (80% of phenolic compounds in the first hour and 50% of anthocyanins in the first few minutes). The NCX showed high antioxidant activity, as evidenced by traditional assays, and inhibited the peroxyl radicals mediated oxidation of a tryptophan-containing peptide. Additionally, NCX inhibited lipid peroxidation in an emulsified system of Sacha inchi oil exposed to accelerated oxidative conditions. In conclusion, the NCX showed good properties as an antioxidant with potential use as a food additive.

Binding of peanut allergen Ara h 2 with Vaccinium fruit polyphenols.

The potential for 42 different polyphenols found in Vaccinium fruits to bind to peanut allergen Ara h 2 and inhibit IgE binding epitopes was investigated using cheminformatics techniques. Out of 12 predicted binders, delphinidin-3-glucoside, cyanidin-3-glucoside, procyanidin C1, and chlorogenic acid were further evaluated in vitro. Circular dichroism, UV-Vis spectroscopy, and immunoblotting determined their capacity to (i) bind to Ara h 2, (ii) induce protein secondary structural changes, and (iii) inhibit IgE binding epitopes. UV-Vis spectroscopy clearly indicated that procyanidin C1 and chlorogenic acid interacted with Ara h 2, and circular dichroism results suggested that interactions with these polyphenols resulted in changes to Ara h 2 secondary structures. Immunoblotting showed that procyanidin C1 and chlorogenic acid bound to Ara h 2 significantly decreased the IgE binding capacity by 37% and 50%, respectively. These results suggest that certain polyphenols can inhibit IgE recognition of Ara h 2 by obstructing linear IgE epitopes.

Bioaccessibility during In Vitro Digestion and Antiproliferative Effect of Bioactive Compounds from Andean Berry ( Vaccinium meridionale Swartz) Juice.

Berry consumption is associated with colorectal-cancer chemoprevention, but digestive conditions can affect this property. The bioaccessibility and apparent permeability coefficients of bioactive compounds from Andean Berry Juice (ABJ) after in vitro gastrointestinal digestion and colonic fermentation were analyzed. The antiproliferative effect of the fermented nondigestible fraction was evaluated against SW480 colon-adenocarcinoma cells. Gallic acid displayed the highest bioaccessibility in the mouth, stomach, small intestine, and colon. However, chlorogenic acid exhibited the highest apparent permeability coefficients (up to 1.98 × 10-4 cm/s). The colonic-fermentation fraction showed an increase of ≥50% antiproliferative activity against SW480 cells (19.32%, v/v), equivalent to those of gallic acid (13.04 µg/g), chlorogenic acid (7.07 µg/g), caffeic acid (0.40 µg/g), ellagic acid (7.32 µg/g), rutin (6.50 µg/g), raffinose (0.14 mg/g), stachyose (0.70 mg/g), and xylose (9.41 mg/g). Bioactive compounds from ABJ are bioaccessible through the gastrointestinal tract and colon fermentation, resulting in antiproliferative activity.

Polyphenol profile and antioxidant activity of the fruit and leaf of Vaccinium glaucoalbum from the Tibetan Himalayas.

Vaccinium glaucoalbum, a perennial evergreen shrub, is naturally distributed in high-altitude areas. In this study, the composition and content of polyphenolic compounds in the fruit and leaf of V. glaucoalbum were characterized. In total, 24 chemical compounds were detected and identified by HPLC-DAD and HPLC-ESI-MS2. Among all the compounds determined, 15 were anthocyanins and detected in fruit, 5 were flavonols and monitored in leaf, and 4 were chlorogenic acids and found in both fruit and leaf. The total anthocyanin content (TAC) of fruit (682mg/100gFW) was the highest among wild Vaccinium berries in China which have been investigated for now, and the total flavonol content of leaf was 2764mg/100gFW. The antioxidant activity of both fruit and leaf was assessed by DPPH and FRAP assays. Given its high TAC and strong antioxidant activity, the fruit of V. glaucoalbum has great potential in functional food.

Hydroquinone analog 4-[(Tetrahydro-2H-pyran-2­yl) oxy] phenol induces C26 colon cancer cell apoptosis and inhibits tumor growth in vivo.

The 4[(Tetrahydro­2H­pyran­2­yl) oxy] phenol (XG­d) hydroquinone analog, is found in Vaccinium vitis­idaea  L. Although it is known for its antioxidant properties and high level of safety, its antitumor activity remains to be elucidated. In the present study, the anticancer effect of XG­d was determined in vitro and in vivo. The cytotoxicity of XG­d against C26 murine colon carcinoma cells was found to occur in a time­ and concentration­dependent manner, whereas little effect was observed in the two normal cell lines (HK­2 and L02) investigated. Oral administration of XG­d (100 mg/kg) had effects on the tumor growth of tumor­bearing mice. Furthermore, marked apoptosis was observed using Hoechst 33258 staining and flow cytometric analysis with annexin V/propidium iodide double staining. XG­d also downregulated the expression of B­cell lymphoma 2 (Bcl­2), increased the expression levels of Bcl­2­associated X protein and activated caspase­9, caspase­3 and poly(adenosine diphosphate­ribose) polymerase. The present study demonstrated for the first time, to the best of our knowledge, that XG­d inhibited cancer cell growth via the induction of apoptosis and was also able to inhibit tumor growth in vivo. These results demonstrated that XG­d may be used as a potential natural agent for cancer therapy with low toxicity.

Protective effect of Vaccinium myrtillus extract against UVA- and UVB-induced damage in a human keratinocyte cell line (HaCaT cells).

Recently, the field of skin protection have shown a considerable interest in the use of botanicals. Vaccinium myrtillus contains several polyphenols and anthocyanins with multiple pharmacological properties. The purpose of our study was to examine whether a water-soluble V. myrtillus extract (dry matter 12.4%; total polyphenols 339.3mg/100 g fw; total anthocyanins 297.4 mg/100 g fw) was able to reduce UVA- and UVB-induced damage using a human keratinocyte cell line (HaCaT). HaCaT cells were pretreated for 1h with extract in a serum-free medium and then irradiated with UVA (8-40 J/cm(2)) and UVB (0.008-0.72 J/cm(2)) rays. All experiments were performed 24h after the end of irradiation, except for oxidative stress tests. The extract was able to reduce the UVB-induced cytotoxicity and genotoxicity (studied by comet and micronucleous assays) at lower doses. V. myrtillus extract reduced lipid peroxidation UVB-induced, but had no effect against the ROS UVB-produced. With UVA-induced damage V. myrtillus reduced genotoxicity as well as the unbalance of redox intracellular status. Moreover our extract reduced the UVA-induced apoptosis, but had no effect against the UVB one. V. myrtillus extract showed its free radical scavenging properties reducing oxidative stress and apoptotic markers, especially in UVA-irradiated cells.

Berry antioxidants: small fruits providing large benefits.

Small berry fruits are consumed because of their attractive colour and special taste, and are considered one of the richest sources of natural antioxidants. Their consumption has been linked to the prevention of some chronic and degenerative diseases. The term 'berry fruits' encompasses the so-called 'soft fruits', primarily strawberry, currants, gooseberry, blackberry, raspberry, blueberry and cranberry. The objective of this review is to highlight the nutraceutical value of berries and to summarize the factors affecting berry fruit antioxidants. Particular attention is given to postharvest and processing operation factors that may affect fruit phytochemical content. The structure-antioxidant relationships for phenolic compounds - the main group of antioxidants in this fruit group - are presented and major areas for future research are identified.

Metabolite profiling of polyphenols in Vaccinium berries and determination of their chemopreventive properties.

A detailed investigation on the chemical composition and chemopreventive activity of Vaccinium floribundum Kunth berries was carried out in comparison with Vaccinium myrtillus L. Berry polyphenols were extracted by using two sequential dynamic maceration steps, which enabled to maximize the yields of secondary metabolites. In particular, phenolic acids and flavonols were extracted from berries using ethyl acetate (EtOAc), whereas anthocyanins were extracted from the residue with 0.6M HCl in methanol (MeOH). The analysis of secondary metabolites in berry extracts was performed by means of two specific HPLC methods. Phenolic acids and flavonols were analyzed on an Ascentis C18 column (250mm×4.6mm I.D., 5µm), with a gradient mobile phase composed of 0.1M HCOOH in H2O and ACN. Anthocyanin analysis was carried out on a Zorbax SB-C18 column (150mm×4.6mm I.D., 5µm), with a gradient mobile phase composed of H2O-HCOOH (9:1, v/v) and MeOH-H2O-HCOOH (5:4:1, v/v/v). Detection was performed by UV/DAD, MS and MS(2). The polyphenol composition of V. floribundum and V. myrtillus was studied in detail. The samples of V. floribundum analyzed in this study had a much higher content of both phenolic acids and flavonols in comparison with V. myrtillus (mean value 41.6±10.2 and 13.7±0.2mg/100g FW, respectively), while V. myrtillus showed a higher amount of anthocyanins if compared with V. floribundum (568.8±8.8 and mean value 376.2±49.9mg/100gFW, respectively). The extracts gave negative results in antimutagenic assays against carcinogens 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) and 4-nitroquinoline-1-oxide (4-NQO), while they performed similarly in both ABTS(+) and DPPH antioxidant assays.

Relationship between polyphenol content and anti-influenza viral effects of berries.

BACKGROUND: Berries are known to have many kinds of biological activities. We focused on their antiviral effect, which has not yet been well evaluated. RESULTS: We compared the anti-influenza viral effects of berries belonging to the genus Vaccinium - 35 species of blueberry (Vaccinium cyanococcus), the Natsuhaze (Vaccinium oldhamii), bilberry (Vaccinium myrtillus) and cranberry (Vaccinium oxycoccos)- with those belonging to the genus Ribes, i.e. blackcurrant (Ribes nigrum). Only Elliott and Legacy among Northern Highbush varieties but many Rabbiteye varieties such as Austin, Baldwin, Brightblue, Festival, T-100 and Tifblue showed anti-influenza viral activity. Natsuhaze, bilberry, cranberry and blackcurrant had high antiviral effects. A relationship was observed between the antiviral effect and total polyphenol content. CONCLUSIONS: Antiviral effects were found to differ markedly between berry species. Rabbiteye varieties tended to have higher antiviral effects than Northern, Southern and Half Highbush blueberry varieties. We also found that Natsuhaze, which has recently been harvested in Japan as a potential functional food, had an antiviral effect comparable to that of bilberry, cranberry and blackcurrant. There was a positive relationship between antiviral activity and polyphenol content, indicating the possibility that polyphenol is one of the key factors in the antiviral effects of berries.

Intraspecific variation in aphid resistance and constitutive phenolics exhibited by the wild blueberry Vaccinium darrowi.

Illinoia pepperi (MacGillivray) infests cultivated highbush blueberries, Vaccinium corymbosum L., in the Northeastern United States. Allopatric resistance to I. pepperi was examined in Vaccinium darrowi Camp, which evolved in the absence of I. pepperi in the Southeastern U.S. V. corymbosum cv. "Elliott", was used as a susceptible control. Between population variability in I. pepperi resistance was assessed by measuring length of the prereproductive period, fecundity, and survivorship on 14 V. darrowi accessions representing 11 discrete wild populations. Length of I. pepperi's prereproductive period and survivorship were not significantly affected. However, differences were detected in fecundity and the intrinsic rate of increase (r ( m )). Within population variability in resistance was measured by confining first instars to 24 accessions from a single wild population of V. darrowi (NJ88-06). Significant differences in the mean total number of aphids occurring after 20 d were only detected between 2 of the 24 V. darrowi accessions. A greater degree of diversity in I. pepperi resistance exists between populations of V. darrowi compared to within a population. Constitutive leaf and stem polyphenolics were identified by HPLC-MS and quantified from 14 of the V. darrowi accessions. The accessions varied in concentrations of five phenolic acids and seven flavonol glycosides, but a correlation was not found between individual or total phenolics and aphid performance. Overall, screening within and between populations of V. darrowi identified promising sources of aphid resistance, but phenolic acid and flavonol glycoside profiles did not predict resistance levels. The mechanism of resistance remains to be identified.

Isolation of high quality RNA from bilberry (Vaccinium myrtillus L.) fruit.

A simple and efficient method is described for isolating high quality RNA from bilberry fruit. The procedure is based on the use of hexadecyltrimethyl ammonium bromide (CTAB), polyvinylpyrrolidone (PVP), and beta-mercaptoethanol in an extraction buffer in order to eliminate the polysaccharides and prevent the oxidation of phenolic compounds. This method is a modification of the one described for pine trees, and yields high-quality RNA suitable for cDNA based methodologies. This method is applicable for a variety of plant tissues.