Flavonoid extracts from chrysanthemum with appropriate anthocyanins turn blue when exposed to iron ions

Although some species that accumulate only cyanidin(Cy)in nature can produce blue flowers through iron ions,there has been no evidence of blue chrysanthemums being generated in this manner.This study revealed that flavonoid extracts from the ray florets of the chrysanthemum cultivar‘Wandai Fengguang’turned blue when exposed to Fe^(3+).Samples that could turn blue were labeled as CB(Cy-determined blue flowers),while samples that did not turn blue were labeled as CN(Cy-determined non-blue flowers).After a series of experiments,a stable screening system was established using flavonoid extracts containing NaAc buffer at pH 5.5 and a total anthocyanin concentration(TAC)of 30 μmol·L^(-1),and the addition of Fe^(3+)from 0 to 0.25 μmol·L^(-1)allowed for the selection of five CB samples from 39 chrysanthemum cultivars.All five CB samples exhibited flower color phenotypes that belonged to Cluster-I with redness(a*)values ranging from 29.03 to 45.99,yellowness(b*)values from-11.31 to 3.77,and brightness(L*)values from 29.07 to 45.99.Additionally,the ratio of TAC to total luteolin concentration(TLC)was found to be a critical factor for distinguishing between CB and CN samples.To realize the desired blue hue in the flavonoid extracts with the participation of Fe^(3+),a TAC to TLC ratio of 2.25 and above is required.Moreover,the protoplasts and ray florets of CB samples that turned blue with the involvement of Fe^(2+)showed great potential for cultivating blue chrysanthemums through ferric-anthocyanin chelate.Overall,this study reveals that blue flowers can be cultivated through the increase in the iron ion concentration,combined with the accumulation of Cy.

松树皮原花青素提取纯化及降血脂作用研究

[目的]研究松树皮原花青素的提取纯化方法和降血脂作用。[方法]分别采用浓度70%乙醇和大孔树脂对松树皮中原花青素进行了提取和纯化;以小白鼠为对象建立动物模型进一步研究了原花青素精提物的降血脂作用。[结果]经NKA大孔树脂纯化后的原花青素纯度达到40%左右;松树皮中原花青素具有降低小白鼠血清中甘油三酯(TG)、总胆固醇(TC)和低密度脂蛋白(LDL-C)含量的作用。[结论]松树皮原花青素提取物在一定程度上能起到降血脂的作用,为其在保健和医药等方面进一步开发利用提供科学依据。

Isolation of three cyanins from Lonicera caerulea L. fruits and its anticancer activity

Lonicera caerulea L.fruit is an excellent source of bioactive compounds.An efficient separation method of cyanins is important for the development of many value-added products and functional food ingredients.High-speed counter-current chromatography(HSCCC) was applied to isolate cyanins from Lonicera caerulea fruits with a biphasic solvent system composed of methyl tert-butyl ether/n-butanol/acetonitrile/water/trifluoroacetic acid(2:2:1:5:0.01,volume ratio).1.41 mg of cyanidin 3,5-O-diglucoside,1.08 mg of cyanidin 3-O-rutinoside and 6.38 mg of cyanidin 3-O-glucoside were obtained from 40 mg of crude extract.The purities of these compounds were 95.8%,92.4% and 97.6%,respectively,as identified by high-performance liquid chromatography–diode array detection(HPLC-DAD) and high-performance liquid chromatography-electrospray ionization mass spectrometryn(HPLC-ESI/MSn).In addition,the dominant anthocyanin,cyanidin 3-O-glucoside was demonstrated cytotoxic response of human hepatocarcinoma SMMC-7721 cells,inducing live cancer cell apoptotic by flow cytometric analysis.

Cyanidin suppresses amyloid beta-induced neurotoxicity by inhibiting reactive oxygen speciesmediated DNA damage and apoptosis in PC12 cells

Amyloid beta（Aβ）-induced oxidative stress is a major pathologic hallmark of Alzheimer＇s disease. Cyanidin, a natural flavonoid compound, is neuroprotective against oxidative damage-mediated degeneration. However, its molecular mechanism remains unclear. Here, we investigated the effects of cyanidin pretreatment against Aβ-induced neurotoxicity in PC12 cells, and explored the underlying mechanisms. Cyanidin pretreatment significantly attenuated Aβ-induced cell mortality and morphological changes in PC12 cells. Mechanistically, cyanidin effectively blocked apoptosis induced by Aβ, by restoring the mitochondrial membrane potential via upregulation of Bcl-2 protein expression. Moreover, cyanidin markedly protected PC12 cells from Aβ-induced DNA damage by blocking reactive oxide species and superoxide accumulation. These results provide evidence that cyanidin suppresses Aβ-induced cytotoxicity, by preventing oxidative damage mediated by reactive oxide species, which in turn inhibits mitochondrial apoptosis. Our study demonstrates the therapeutic potential of cyanidin in the prevention of oxidative stress-mediated Aβ neurotoxicity.

Two diglucosylated anthocyanins from <i>Combretum paniculatum</i>flowers

From Combretum paniculatum flowers, two diglucosylated derivatives from cyanidin and pelargonidin were identified using chromatographic (TLC), chemical (degradation by hydrolysis, tests of revelations) and spectral [UV-visible, 1H-NMR (1H and 13C, TOCSY-1D, DQF-COSY, NOESY-2D)] methods. These pigments were found to consist of cyanidin 3,5-O-β-D-diglu-copyranoside and pelargonidin 3。

Studies on Anthocyanin in Purple Flower of Helichrysum bracteatum

This paper puts forward a biochemical analysis of the anthocyanins in the petals of Helichrysum bracteatum flower which takes a deep purple color. A pure antho-cyanin chloride crystal is obtained and identified as a cyanin glucoside by IR, UV and MS techniques. This paper also presents a study on the preservation mechanism of the flower color and flower shape according to the histochemical and anatomical characteristics of the petals.

Beneficial effects of anthocyanins against diabetes mellitus associated consequences——A mini review

Anthocyanins(ACN) are water-soluble pigments, belonging to flavonoids, and are present in almost all fruits, and vegetables at varying concentration. About 635 ACN were distinguished based on the position and number of methoxyl and hydroxyl moieties in the basic structure of ACN. Pelargonidin, cyanidin, delphinidin, malvidin, peonidin, and petunidin are extensively studied anthocyanidins. The absorption, bioavailability, metabolism, pharmacokinetics, molecular mechanism, and analytical techniques of several phytochemicals were described. The biological benefits(antidiabetic, anti-neuro-disorder, anti-cardiovascular diseases, antigastrointestinal diseases, and disorders) of flavonoids and ACN have been reported. Several in vitro, and in vivo reports demonstrated that ACN-rich plant extracts ameliorate the diabetesassociated consequences by reducing the glucose absorption, ROS production, oxidative stress, glomerular angiogenesis, lipid synthesis, and FoxO1 and adipose triglyceride lipase expressions, and improve the insulin secretion, insulin sensitivity, glucose tolerance, glucose uptake, glucose consumption, antioxidant activity. The literature search was made in Scopus, Google Scholar, PubMed using the keywords "anthocyanin" and "diabetes". The documents were carefully checked for the relevance to the current manuscript and the selection was made without any chronological restriction. The present manuscript summarizes the updated reports on antihyperglycemic properties of ACN.

Application of Cyanidin in Quantitative Estimation of Metals in Fish Samples

The use of cyanidin as a metallochromic agent in analyses of heavy metal is reported. Cyanidin is a ligand that was extracted from Gmelina arborea fruit and characterized. The cyanidin was used to form complexes with metals in five fish samples for the quantitative determination of Cu, Zn, Ca and Mg. The optimum pH for absorbances of the cyanidin-metal complexes was observed at 5. Experimental results obtained using cyanidin were compared with analyses results obtained by Atomic absorption spectrophotometry (AAS) and both methods were evaluated using paired T-test to ascertain the suitability of cyanidin as metallochromic agent for the quantitative determination of heavy metals in fish samples. A null hypothesis that cyanidin method is a good alternative to AAS was accepted for the analyses of Cu and Zn (p > 0.05). The paired T-test, however rejected the null hypothesis for the determination of Ca and Mg (p < 0.05). This study has provided a cheap, sensitive, rapid, simple and easy method for metal determination in analytical samples.

Isolation and Characterization of Anthocyanins in Four Varieties of Vigna subterranea (Fabaceae)

By chromatographic methods (HPLC, TLC) coupled with spectral methods (LC-MS, TLC-MS) and chemical revelation tests, anthocyanins from four Vigna subterranea varieties (M4, D3, KVS350, KVS97) were isolated and identified as malvidin 3-O-β-D-glucopyranoside, paeonidin-3-O-β-D-glucopyranoside, petunidin-3-O-β-D-glucopyranoside, cyanidin 3-O-β-D-glucopyranoside, del- pinidin-3-O-β-D-glucopyranoside.

Arabidopsis TT19 Functions as a Carrier to Transport Anthocyanin from the Cytosol to Tonoplasts

Anthocyanins are synthesized in the cytosolic surface of the endoplasmic reticulum （ER） but dominantly accumulate in the vacuole. Little is known about how anthocyanins are transported from the ER to the vacuole. Here, we provide evidence supporting that Transparent Testa 19 （TT19）, a glutathione 5-transferase （GST）, functions as a carrier to transport cyanidin and/or anthocyanins to the tonoplast. We identified a novel tt19 mutant （tt19-7）, which barely accumulates anthocyanins but produces a 36% higher level of flavonol than the wild-type （WT）, from ethyl methanesulfonate mutagenized seeds. Expressing TT19-fused green fluorescence protein （GFP） in tt19-7 rescues the mutant phenotype in defective anthocyanin biosynthesis, indicating that TT19-GFP is functional. We further showed that TT19-GFP is localized not only in the cytoplasm and nuclei, but also on the tonoplast. The membrane localization of TT19-GFP was further ascertained by immunoblot analysis. In vitro assay showed that the purified recombinant TT19 increases water solubility of cyanidin （Cya） and cyanidin-3-O-glycoside （C3G）. Compared with C3G, Cya can dramatically quench the intrinsic tryptophan fluorescence of TT19 to much lower levels, indicating a higher affinity of TT19 to Cya than to C3G. Isothermal titration calorimetry analysis also confirmed physical interaction between TT19 and C3G. Taken together, our data reveal molecular mechanism underlying TT19-mediated anthocyanin transportation.

The Formation of Anthocyanic Vacuolar Inclusions in Arabidopsis thaliana and Implications for the Sequestration of Anthocyanin Pigments

Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants. Inside the vacuole, anthocyanins can be found uniformly distributed or as part of sub-vacuolar pigment bodies, the Anthocyanic Vacuolar Inclusions （AVIs）. Using Arabidopsis seedlings grown under anthocyanin-inductive conditions as a model to un- derstand how AVIs are formed, we show here that the accumulation of AVIs strongly correlates with the formation of cyanidin 3-glucoside （C3G） and derivatives. Arabidopsis mutants that fail to glycosylate anthocyanidins at the 5-0 position （Sgt mutant） accumulate AVIs in almost every epidermal cell of the cotyledons, as compared to wild-type seedlings, where only a small fraction of the cells show AVIs. A similar phenomenon is observed when seedlings are treated with vanadate. Highlighting a role for autophagy in the formation of the AVIs, we show that various mutants that interfere with the autophagic process （atg mutants） display lower numbers of AVIs, in addition to a reduced accumulation of anthocyanins. Interestingly, vanadate increases the numbers of AVIs in the atg mutants, suggesting that several pathways might participate in AVl formation. Taken together, our results suggest novel mechanisms for the formation of sub-vacuolar compartments capable of accumulating anthocyanin pigments.