Decrease In Anthocyanin Content Research Articles

Development of Ultrasound-Processed Poppy (Papaver rhoeas L.) Sherbet Enriched with Bee Bread Using Response Surface Methodology: Changes in Shelf Life.

This research aimed to investigate the effects of ultrasound treatment on the quality characteristics of optimized functional bee bread-enriched poppy sherbet. Antioxidant activity capacity, antimicrobial activity, phenolic compounds, ascorbic acid, organic acid and sugar composition, and sensory properties were performed under storage conditions. The present research was the first to express the effect of ultrasound on the bioactive components in a functional poppy sherbet enriched with bread, using the response surface methodology (RSM) optimization. The maximum optimization, radical scavenging activity (DPPH), total phenolic content (TPC), total anthocyanin content (TAC), and general acceptability values were determined. When comparing the 0th- and 21st-day samples of bee bread-fortified functional poppy sherbets, it was observed that the TPC was decreased (p < 0.05). It was also noted that there was no significant decrease in the total flavonoids on day 21. In storage, a decrease in anthocyanin content was observed. Among phenolic compounds, gallic acid had the highest content. While citric acid was found in the highest amount of organic acid, sucrose (6.25 g/L) was found in the highest amount of sugar components 0th day, while MIC values against Micrococcus luteus were lower. The data from this study will be important input for future work.

Evaluation of mechanical properties, heating rate and radio frequency explosive puffing (RFEP) quality of purple sweet potato under different moisture contents and moisture equilibrium process

The effects of different initial moisture contents (15–55%) and moisture equilibrium process (MEP) on the mechanical properties of the gas-blocking surface layer of purple sweet potato chips and the radio frequency (RF) heating rate, uniformity, and radio frequency explosion puffing (RFEP) quality were discussed in this article. Low-field nuclear magnetic resonance indicated that hot-air pre-drying reduced the amount of free water and caused the transfer of immovable water to bound water. This process was accompanied by an increase in the thickness and elastic modulus of the gas-blocking surface layer, resulting in a significant increase in the RF heating rate and uniformity. Prolonged RF heating time led to a decrease in anthocyanin content. The results demonstrated that the puffing rate initially increased and then decreased with increasing initial moisture content. The puffed sample with an initial moisture content of 45% exhibited the highest puffing rate, crispiness, and porosity. X-ray micro-tomography results reveal that MEP improved the morphology of puffed products, ensuring even distribution of small pores and reducing the presence of hard edges. In conclusion, considering the heating time and anthocyanin retention rate, the initial moisture content ranges from 35% to 45% after MEP was the best pre-treatment.

Accumulation patterns of anthocyanin and γ-oryzanol during black rice grain development.

Pigmented rice, especially black rice, is gaining popularity as it is rich in antioxidants such as anthocyanins and γ-oryzanol. At present, knowledge about temporal control of biosynthesis and accumulation of antioxidants during grain development is limited. To address this, the accumulation patterns of anthocyanins and γ-oryzanol were assessed in two distinct black rice genotypes over the course of grain development, and the expression of known regulatory genes for anthocyanin biosynthesis was examined. The results indicated that total γ-oryzanol content increased continuously throughout grain development, while total anthocyanins peaked at dough stage (15 to 21 days after flowering) followed by a decline until grain maturity in both genotypes. However, the rate of decrease in anthocyanin content differed between genotypes, and a more prominent decline in cyanidin 3-O-glucoside (C3G) relative to peonidin 3-O-glucoside (P3G) was observed for both. Anthocyanin content was closely linked with the expression of key regulatory genes in the MBW (MYB-bHLH-WD40) complex. This improved knowledge of the genotype-specific biosynthesis (anthocyanins only) and accumulation patterns of anthocyanins and γ-oryzanol can inform subsequent research efforts to increase concentrations of these key antioxidants in black rice grains.

Sucrose-delaying flower color fading associated with delaying anthocyanin accumulation decrease in cut chrysanthemum

As fresh ornamental crops, vase life and post-harvested quality of cut flowers have attracted much attention. Flower color fading is the prominent defect in red and purple cut flowers, especially in cut chrysanthemum which have a relative long vase life. Here, the effect of sucrose on change in anthocyanin contents during the vase life of ‘Dante Purple’ cut chrysanthemum was studied. Results showed that 500 mM sucrose as holding solution could significantly delay the decrease in anthocyanin content and maintain the ornamental value for as long as 38 vase days. Moreover, the sucrose also increased the flower diameter, soluble sugar contents and total antioxidant capacity, while decreasing the malondialdehyde contents. Further studies suggested that the transcript levels of anthocyanin biosynthetic genes and transcription factors, CmMYB6 and CmMYB#7, had continuously decreased during the vase life. The changes in these genes expression patterns was retarded by the sucrose treatment, except for CmMYB#7 which is a repressor of anthocyanin biosynthesis gene expression. The decline in relative expression of CmMYB#7 was accelerated by sucrose. These results have supplied clues to study the mechanism whereby sucrose serves as a signal molecule to regulate anthocyanin biosynthesis.

Effect of radiation processing on physico-chemical quality and inhibition of yeast and mold and aerobic bacterial count in natural plum juice during refrigerated storage

Fully red plums (Cv. Santa Rosa) harvested at proper maturity were processed into juice and packed in polypropylene (PP) bottles. The packaged juice was irradiated at 0.5 kGy and stored at 3 ± 1 °C for 50 days. Samples were evaluated at intervals of 10 days for physico-chemical, microbiological and sensory quality attributes. Results indicated that dose of 0.5 kGy maintained higher levels of total soluble solids, sugars and total ascorbic acid in juice towards later storage periods compared to control. Dose of 0.5 kGy significantly (p ≤ 0.05) enhanced total phenols in plum juice by 2.3 % following irradiation. Anthocyanins content of plum juice decreased both with dose and storage, however after 50 days decrease in anthocyanin content was 30.8 % in un-irradiated juice compared to 23.3 % in 0.5 kGy treated juice. Among individual anthocyanins, monoglycoside anthocyanins especially cyanidin-3-rutinoside was less stable to irradiation compared to diglycoside anthocyanins. DPPH and hydroxyl radical scavenging activity of juice increased by 6.8 % and 4.9 % above control after irradiation at 0.5 kGy. Microbial populations significantly reduced by irradiation at 0.5 kGy and about 1 log reduction in yeast and mold count was observed after irradiation. Dose of 0.5 kGy was sufficient to reduce total bacterial levels below detection limit up to 20 days of storage. Sensory analysis indicated that un-irradiated plum juice was unacceptable within 20–30 days while 0.5 kGy treated juice was acceptable up to 50 days of refrigerated storage.

ATP-binding cassette protein ABCC8 promotes anthocyanin accumulation in strawberry fruits

Anthocyanins are important health-promoting flavonoid compounds that substantially contribute to fruit quality. Anthocyanin biosynthesis and most regulatory mechanisms are relatively well understood. However, the functions of anthocyanin transport genes in strawberry fruit remain unclear. In this study, a gene encoding an ATP-binding cassette (ABC) protein of type C, ABCC8, was isolated from strawberry fruits. qRT-PCR analysis demonstrated that the transcript levels of FvABCC8 were the highest and were strongly correlated with anthocyanin accumulation during strawberry fruit ripening. Transient overexpression and RNAi of FvABCC8 led to an increase and decrease in anthocyanin content in strawberry fruits, respectively. Moreover, the ABCC8 promoter was activated by MYB and bHLH transcription factors MYB10, bHLH33, and MYC1. Sucrose enhanced anthocyanin accumulation in FvABCC8-overexpressing Arabidopsis, particularly at higher concentrations. FvABCC8-overexpressing lines were less sensitive to ABA during seed germination and seedling development. These results suggest that strawberry vacuolar anthocyanin transport may be mediated by the ABCC transporter ABCC8, the expression of which may be regulated by transcription factors MYB10, bHLH33, and MYC1.

Integrated Transcriptome and Biochemical Analysis Provides New Insights into the Leaf Color Change in Acer fabri

Acer fabri is a widely distributed ornamental tree with colorful leaves and high ornamental value. Its young leaves change from red to red and green until turning fully green. To understand the mechanism of leaf color change, transcriptome sequencing and pigment content determination were performed in three stages during the leaf color change of A. fabri. In total, 53,550 genes, including 838 transcription factors (TFs), were identified by transcriptome sequencing. In addition, the results of orthogonal partial least squares-discriminant analysis (OPLS-DA) of three pigments in the three stages of leaf color development suggested that carotenoids played a major role in the process of leaf color change from red to red-green, whereas anthocyanins played an important role in the process of leaf color change from red to green. Based on weighted gene co-expression network analysis (WGCNA), Af0034384 (HSFB2A), Af0051627 (NMT1), and Af0052541 (THY-1) were selected as hub genes from characteristic modules with significant correlation between carotenoids and anthocyanins. The results of gene network regulation maps and real-time fluorescence quantitative PCR (qRT-PCR) showed that Af0010511 (NAC100) upregulated the expression of Af0034384 (HSFB2A), leading to an increase in carotenoid content and the gradual greening of leaves during the transition from red to green. However, during the transition from red to green leaves, Af0033232 (NAC83) and Af0049421 (WRKY24) downregulated the expression of Af0051627 (NMT1) and Af0052541 (THY-1), respectively, leading to a decrease in anthocyanin content and the complete greening of leaves. These results could provide new ideas for studying the molecular mechanism of leaf color change in A. fabri and other species.

The multifaceted roles of R2R3 transcription factor HlMYB7 in the regulation of flavonoid and bitter acids biosynthesis, development and biotic stress tolerance in hop (Humulus lupulus L.)

Hop (Humulus lupulus) biosynthesizes the highly economically valuable secondary metabolites, which include flavonoids, bitter acids, polyphenols and essential oils. These compounds have important pharmacological properties and are widely implicated in the brewing industry owing to bittering flavor, floral aroma and preservative activity. Our previous studies documented that ternary MYB-bHLH-WD40 (MBW) and binary WRKY1-WD40 (WW) protein complexes transcriptionally regulate the accumulation of bitter acid (BA) and prenylflavonoids (PF). In the present study, we investigated the regulatory functions of the R2R3-MYB repressor HlMYB7 transcription factor, which contains a conserved N-terminal domain along with the repressive motif EAR, in regulating the PF- and BA-biosynthetic pathway and their accumulation in hop. Constitutive expression of HlMYB7 resulted in transcriptional repression of structural genes involved in the terminal steps of biosynthesis of PF and BA, as well as stunted growth, delayed flowering, and reduced tolerance to viroid infection in hop. Furthermore, yeast two-hybrid and transient reporter assays revealed that HlMYB7 targets both PF and BA pathway genes and suppresses MBW and WW protein complexes. Heterologous expression of HlMYB7 leads to down-regulation of structural genes of flavonoid pathway in Arabidopsis thaliana, including a decrease in anthocyanin content in Nicotiana tabacum. The combined results from functional and transcriptomic analyses highlight the important role of HlMYB7 in fine-tuning and balancing the accumulation of secondary metabolites at the transcriptional level, thus offer a plausible target for metabolic engineering in hop.

Fortification of Pectin/Blackberry Hydrogels with Apple Fibers: Effect on Phenolics, Antioxidant Activity and Inhibition of α-Glucosidase.

The objective of this study was to prepare hydrogels based on pectin and blackberry juice and additionally to fortify those hydrogels with apple fiber. For that purpose, two types of pectin (low methoxylated and high methoxylated) were used, and fortification was conducted with the addition of 10% of apple fiber. The hydrogels were evaluated for phenolic compounds, antioxidant activity and inhibition of α-glucosidase. In addition, the stability of these parameters after 8 months of storage was evaluated. Pectin type and addition of apple fiber had an impact on investigated parameters. Low methoxylated pectin hydrogels had a higher concentration of anthocyanins than high methoxylated pectin hydrogels, while the addition of apple fibers caused a decrease in anthocyanin content. However, fortified hydrogels had higher antioxidant activity due to the presence of phenolics from apple fibers. The results showed that anthocyanins were more favorable in inhibiting α-glucosidase because samples with higher anthocyanins concentration had lower IC50 values. Obtained hydrogels can be used as intermediate products or ingredients (like fruit fillings or spreads) for the improvement or development of novel food products to increase their fiber content and antioxidant potential.

Colorful and health improving Chinese steamed bread fortified by anthocyanin‐rich extract of butterfly pea flower

Butterfly pea flower contains many bioactive substances. To make more use of it, an approach of adding butterfly pea flower extract (BPFE) to Chinese steamed bread (CSB) as a natural colorant and functional ingredient was applied. The objective of this study was to investigate the effect of BPFE levels (0–30%) on phytochemical, textural, and sensory properties of CSB. Total anthocyanins, free polyphenols, DPPH radical scavenging capacity, and reducing power of CSB were enhanced by increasing BPFE level. BPFE-fortified CSB appeared blue in color. However, steaming process caused obvious decrease in anthocyanin content and blueness of CSB. Although addition of 30% BPFE significantly reduced the springiness, cohesiveness and elasticity of CSB, CSB with 0–30% BPFE had similar sensory scores in flavor, texture, and overall preferences. Blue healthy CSB having high phytochemicals and antioxidant activities as well as acceptable sensory attributes can be manufactured by the addition of 20–30% BPFE. Practical applications Consumption of traditional staple foods fortified with natural functional ingredients having more bioactive components is a great benefit to the health of human beings and fits current clean-label trend in food market. Since the flowers of butterfly pea are rich in bioactive anthocyanins, phenolic acids, and flavonols, they were extracted by hot water and prepared into BPFE in this study. The study demonstrated that butterfly pea flower or its extract as a natural functional ingredient can be utilized in steamed bread. Blue healthy CSB having good nutritional, antioxidantive, and sensory quality can be produced by using butterfly pea flowers.

Functional Characterization of Flavanone 3-Hydroxylase (F3H) and Its Role in Anthocyanin and Flavonoid Biosynthesis in Mulberry.

Mulberry (Morus spp., Moraceae) is an important economic crop plant and is rich in flavonoids and anthocyanidins in ripe fruits. Anthocyanins are glycosides of anthocyanidins. Flavanone 3-hydroxylase (F3H) catalyzes the conversion of naringenin into dihydroflavonols and is responsible for the biosynthesis of flavonols and anthocyanidins. In this study, MazsF3H was cloned and characterized from Morus atropurpurea var. Zhongshen 1. Conserved motif analysis based on alignment and phylogenetic analysis indicated that MazsF3H belonged to 2-oxoglutarate-dependent dioxygenase and MazsF3H clustered with F3Hs from other plants. MazsF3H was located in both nucleus and cytosol. MazsF3H was expressed in stems, leaves, stigmas and ovaries, except buds. F3H expression levels showed a positive and close relationship with anthocyanin content during the anthocyanin-rich fruit ripening process, while it showed a negative correlation with anthocyanin content in LvShenZi, whose fruits are white and would not experience anthocyanin accumulation during fruit ripening. Significantly different F3H expression levels were also found in different mulberry varieties that have quite different anthocyanin contents in ripe fruits. Overexpression MazsF3H in tobacco showed unexpected results, including decreased anthocyanin content. Down-regulation of F3H expression levels resulted in co-expression of the genes involved in anthocyanin biosynthesis and a significant decrease in anthocyanin content, but the change in total flavonoid content was subtle. Our results indicated that F3H may play quite different roles in different varieties that have quite different fruit colors. In addition, possible complex regulation of flavonoid biosynthesis should be further explored in some of the featured plant species.

Rainfall-induced premature senescence modulates biochemical and essential oils profiles in Pelargonium graveolens L′Hér. under sub-tropical climate

Pelargonium graveolens L′Hér is a commercially important aromatic plant. The essential oil is used in fragrances, flavour and cosmeceutical industries. The essential oil is secreted in the glandular trichomes distributed mainly on the leaves. In India, P. graveolens is growing only in specific climatic conditions due to the susceptibility of plants to rainfall, high humidity and waterlogging stress. This study aims to analyze rainfall-induced premature senescence in P. graveolens at six phenotypic leaf senescence stages. The physiological and biochemical parameters, cell viability, trichomes density, essential oil yield and variation in chemical constituents were evaluated. Results show a significant increase in chlorophyll-a and b, and a decrease in anthocyanin content. Also, the protein content, MDA, SOD, H2O2, catalase, electrolyte leakage was significantly higher, and cell viability decreased with the progression of senescence. The gland density on leaves was reduced during the advancement of senescence. The GC and GC-MS analysis showed that the senescence significantly modulates oil constituents and oils yield (0.048–0.123%) at different senescence stages. Overall, this study confirms that rainfall induces premature senescence in P. graveolens, significantly affecting essential oil yield and constituents.

Addition of Medicinal Plants Increases Antioxidant Activity, Color, and Anthocyanin Stability of Black Chokeberry (Aronia melanocarpa) Functional Beverages.

The present study investigates the effect of the addition of medicinal plants, such as lady’s mantle, lavender, rosehip, and meadowsweet, on the chemical composition, antioxidant activity, and color intensity of ready-to-drink aronia nectar during pasteurization and long-term storage. Pasteurization caused a significant decrease in anthocyanin content of aronia nectar, which reduced to 20% of the initial value after four months of storage. Herbs provided different protection to aronia anthocyanins that degraded more slowly during the four-month storage compared to pasteurized control without herbs. The addition of medicinal plants enriched aronia nectar with phenolic compounds and increased its antioxidant activity by up to 52% in meadowsweet-aronia nectar. Moreover, it was accompanied by a color intensity magnification due to co-pigmentation of aronia anthocyanins and herbal phenolics. In contrast to anthocyanins, which constantly degraded during the whole period, color intensity began to stabilize after 30 days, demonstrating that co-pigmentation was progressively established during the time and rosehip provided the best stabilization of aronia nectar color. Current research demonstrates for the first time that medicinal plants such as lady’s mantle, rosehip, and especially meadowsweet can be used to increase antioxidant activity, color, and anthocyanin stability of black chokeberry functional beverages.

Anthocyanin content in raspberry and elderberry: The impact of cooking and recipe composition

BackgroundAnthocyanins are known phytochemicals with beneficial properties for human health. The most important route of entry is by consumption of anthocyanins’ naturally rich food such as berries and red wine, in its natural form or as a part of recipes. The effect of cooking methods (boiling, steaming and baking) and recipe composition with two different berries, raspberry and elderberry, on the content of anthocyanins was investigated. Raspberries and elderberries were cooked either in a pan with water, in steam, or baked in the oven. Four recipes containing raspberries and elderberries were prepared: jam, crumble, muffin and mousse. Anthocyanin content was quantified by HPLC-DAD. ResultsGenerally, and compared to raw fruit, a reduction of anthocyanin content after cooking was observed, independently of the heating process. Elderberries were more prone to decrease anthocyanin content after cooking process. Nevertheless, about 70% of the anthocyanins were recovered from the fruit and the water used in the cooking process. Berry anthocyanins’ content decreased the most in jam, and in recipes with baking soda. As opposed to jam, their inclusion in mousse led to almost no decrease in anthocyanin content. ConclusionAll cooking methods tested led to a loss of the original anthocyanin content in berries but, in recipes without a thermal treatment, anthocyanin lost was minimal. These results support the incorporation of berries in cooking processes, particularly those that do not require heat, as a valid alternative to increase phytochemical consumption such as anthocyanins.

Functional characterization of two chalcone isomerase (CHI) revealing their responsibility for anthocyanins accumulation in mulberry

Mulberry (Morus sp., Moraceae) is an important economic crop plant and mulberry fruits are rich in anthocyanidins. Chalcone isomerase (CHI) catalyzes the conversion of chalcones to flavanones providing precursors for biosynthesis of anthocyanidins. In this study, bona fide CHIs were cloned and characterized from different Morus species with differently colored fruits (Morus multicaulis, Mm and Morus alba variety LvShenZi, LSZ). Enzymatic assay of MmCHI1 and MmCHI2 showed that they can utilize naringenin chalcone as substrate. The catalytic efficiency of MmCHI2 and LSZCHI2 are approximately 200 and 120-fold greater than that of MmCHI1 respectively. Phylogenetic analysis showed the two mulberry CHIs belonged to different sub-clade of Type I CHI1 named type IA (CHI2) and type IB (CHI1). Type IB CHIs are mulberry specific. MmCHI1 and MmCHI2 had similar expression profiles and showed preferred expression in fruits. In addition, both mulberry CHI1 and CHI2 played roles in the response to excess zinc stress and sclerotiniose pathogen infection. Both MmCHI1 and MmCHI2 expression levels showed positive close relationship with anthocyanins content during fruit ripening process. The co-expression of MmCHI1 and MmCHI2 was observed during fruit ripening process and in transgenic mulberry. VIGS (virus induced gene silence) targeting on MmCHI1 and MmCHI2 showed significant down-regulation of MmCHI2 instead of MmCHI1 would result in significant (about 50%) decrease in anthocyanins content. MmCHI2 is the dominant CHI for anthocyanins accumulation in mulberry. The results presented in this work provided insight on bona fide CHIs in mulberry and reveal their roles in anthocyanins accumulation.

Ectopic expression of DoFLS1 from Dendrobium officinale enhances flavonol accumulation and abiotic stress tolerance in Arabidopsis thaliana.

Flavonols are important active ingredients that are found in abundance in Dendrobium officinale. Research on flavonol biosynthesis currently focuses on the more ubiquitous kaempferol and quercetin, but little is known on the biosynthesis of myricetin. Notably, flavonol synthase (FLS), which is responsible for the biosynthesis of flavonols, has not yet been identified. In this study, we isolated a flavonol synthase, DoFLS1, from Dendrobium officinale. DoFLS1 harbors conserved 2-oxoglutarate-dependent dioxygenase-specific and FLS-specific motifs. DoFLS1 is a cytoplasmic protein. DoFLS1 was universally expressed in roots, stems, and leaves of juvenile and adult D. officinale plants. DoFLS1 expression was strongly correlated in juvenile and adult D. officinale plants (R2 = 0.86 and 0.98, respectively; p < 0.01) with the average of corresponding flavonol levels. Transgenic Arabidopsis thaliana expressing DoFLS1 exhibited a 1.24-fold increase in flavonol content and a 25.78% decrease in anthocyanin content compare to wild-type plants, possibly resulting from a 78.61% increase in myricetin level. Moreover, the loss of anthocyanin was attributed to decreased expression of dihydroflavonol reductase (DFR) and anthocyanidin synthase (ANS) genes in transgenic A. thaliana that expressed DoFLS1. DoFLS1 also complemented the deficiency in flavonol of the A. thaliana fls1-3 mutant, which had reduced anthocyanin but increased flavonol content relative to the fls1-3 mutant. In addition, DoFLS1 was significantly upregulated after treatment with cold, drought or salicylic acid. These findings provide genetic evidence for the involvement of DoFLS1 in the biosynthesis of flavonol and in response to abiotic stresses.

Influence of Biofortified Colored Wheats (Purple, Blue, Black) on Physicochemical, Antioxidant and Sensory Characteristics of Chapatti (Indian Flatbread).

Biofortified colored wheat (black, blue, and purple) is rich in anthocyanins and phenolic acid compounds that impart positive physiological effects in humans. A large proportion of wheat is consumed in the form of Chapatti in Asian countries. The effect of chapatti cooking on the proximate composition, bioactive compounds (anthocyanins and phenolics), and antioxidant activities of these wheat varieties were checked in this study. Apart from acceptable sensory parameters, good taste, and soft texture of chapatti, biofortified colored wheat chapatti and flour had higher dietary fibers, protein content, and lower carbohydrate content. Higher soluble and insoluble phenolic compounds, anthocyanin content, and antioxidant activity were in the order of black > blue > purple > white. Chapatti making has reduced their antioxidant activity and anthocyanin content in comparison to flour. Moreover, the reduction in antioxidant activity is less as compared to the decrease in anthocyanin content. Our results suggest that colored wheat can be a better alternative to normal wheat for preparing chapatti as it would have additional health-promoting activities.

Physicochemical, microstructural, bioactivity and viability characteristics of probiotic spray-dried raisin powder

This study aims to assess the effect of different concentrations of maltodextrin (MD; 0, 10, and 20% w/w) and pectin (PC; 0, 5, and 10% w/w) as wall materials on the survival of Bacillus coagulans (B. coagulans) in the raisin juice powder (RJP). After drying process, various physicochemical, structural, bioactivity and viability of probiotic-incorporated RJPs were investigated. Results showed that all powders exhibited viable cell counts above 4.0 log CFU/g after spray drying. A positive impact on survival of B. coagulans from the use of a mixed carrier coatings (MD-PC) was observed throughout the experiments. Moreover, RJP yield was significantly increased compared to the control, varied from 19.6 to 48.0% based on the combination of carriers (20% MD: 5% PC). Also, among carrier treatments, those containing high levels of MD (20%) exhibited lowest moisture content and water activity, while solubility was changed vice versa, reaching values above 80%. RJP formulated with 10% MD and 10% PC indicated the highest value of total phenolic compound content. Also, based on our results, a slight decrease in anthocyanin content was found with increasing carrier concentrations, which it negatively correlated with lightness value (L*). In conclusion, the spray dried treatment composed of 10% MD and 5% PC was demonstrated to be efficient as coating carriers to protect the viability of probiotic and to maintain the quality attributes of RJP and can be comparably applied for other types of fruit juices with similar chemical composition.

Expression of the subgroup IIIf bHLH transcription factor CpbHLH1 from Chimonanthus praecox (L.) in transgenic model plants inhibits anthocyanin accumulation.

Overexpression of CpbHLH1 in Arabidopsis and tobacco resulted in a dramatic decrease in anthocyanin accumulation by repressing the expression of late biosynthesis genes in the flavonoid biosynthesis pathway. Many basic helix-loop-helix (bHLH) transcription factors (TFs) of subgroup IIIf have been characterized as anthocyanin-associated activators in higher plants, but information regarding bHLH TFs that inhibit anthocyanin accumulation remains scarce. In this study, the subgroup IIIf bHLH TF CpbHLH1 from Chimonanthus praecox (L.) was identified as a negative regulator of anthocyanin accumulation. Our results showed that overexpression of CpbHLH1 in model plant species, Arabidopsis and tobacco, resulted in a dramatic decrease in anthocyanin content, whereas the content of proanthocyanidin was little affected. Quantitative RT-PCR (qRT-PCR) assays of the structural genes in the flavonoid biosynthesis pathway revealed that CpbHLH1 inhibits anthocyanin accumulation mainly through repressing the expression of late biosynthesis genes (LBGs). Interactions between CpbHLH1 protein and AtPAP1/NtAN2 protein were detected via yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. This is the first bHLH repressor of anthocyanin biosynthesis identified in dicotyledons. These results can help us better understand the anthocyanin regulatory network in plants and may provide insights into the diverse functions of bHLH proteins.

Transcriptome and chemical analysis reveal putative genes involved in flower color change in Paeonia ‘Coral Sunset’

The flower color of Paeonia ‘Coral Sunset’ and ‘Pink Hawaiian Coral’ changes from coral to pink to pale yellow during flowering, which confers high ornamental value to these two cultivars. However, the molecular mechanism underlying flower color change is still unclear. In this study, flavonoids in petals of Paeonia ‘Coral Sunset’ and ‘Pink Hawaiian Coral’ at seven flowering stages were analyzed to explore the effects of the flavonoid component on changes in flower color. In addition, four cDNA libraries of ‘Coral Sunset’ during the critical blooming stages were constructed and the transcriptome was sequenced to investigate the molecular mechanism underlying changes to flower color. Two anthocyanins (cyanidin-3,5-di-O-glucoside and peonidin-3,5-di-O-glucoside) were detected in both cultivars. Total anthocyanin content in both cultivars accumulated continuously from stages 1–3 and then decreased sharply. Correlation analysis showed that the change in flower color from coral to pink to pale yellow is due to a significant decrease in anthocyanin content. A total of 91,583 Unigenes were obtained in ‘Coral Sunset’, 33,962 (37.08%) of which were annotated to major databases. Based on the enrichment analysis of differentially expressed genes, eight structural genes (CHS, F3H, F3′H, FLS, DRF, ANS, ANR and UFGT) and 13 transcription factors (five MYB, three bHLH, one WD40, one HY5, one PIF3, one COP1 and two PHY) related to flavonoid biosynthesis were screened. The qRT-PCR results were generally consistent with the high-throughput sequencing results. This research will provide a foundation to clarify the mechanisms underlying changes in flower color of herbaceous peony.