Identification and quantification of anthocyanin pigments in colored rice

Anthocyanin pigments from varieties of black, red and wild rice were identified and quantified to evaluate their potential as nutritional function, natural colorants or functional food ingredients. Anthocyanin extraction was conducted with acidified methanol with 0.1M HCl (85:15, v/v) and identification of anthocyanin, aglycone and sugar moieties was conducted by comparison with purified standards by HPLC, Ultraviolet-Visible absorption spectrophotometer and paper chromatography. Black and wild rice showed three different types of pigments by HPLC whereas red rice variety did not show any anthocyanins. Out of three pigments detected, one (peak 2) was characterized as cyanidin-3-glucoside (C3G) by comparison of spectroscopic and chromatographic properties with an authentic standard, and another (peak 3) was tentatively identified as cyanidin-fructoside on the basis of spectroscopic properties with λ_max of aglycone in 1% HCl methanol at 537 nm, electrospray ionization mass spectra with major ions at 449 and 287 m/z and chromatographic properties. But another pigment (peak 1) has not been characterized. The most abundant anthocyanin in black and wild rice was C3G.     

Environmental and genetic variation of phenolic compounds in red raspberry

Red raspberry (Rubus idaeus L.) is an economically important berry crop that contains numerous phenolic compounds with potential health benefits. It is known that the content of phenolics is affected by processing factors, but limited information is available on the influence of cultural factors or genotype. To clarify this issue, phenolic compounds were analysed from a diverse range of raspberry cultivars grown under northern European conditions, in Finland.The content of phenolic compounds varied widely and significantly between cultivars. The quercetin content ranged from 0.32 (yellow cultivar) to 1.55 mg/100 g fresh weight (fw) (cv. Balder). The ellagic acid content varied from 38 (cv. Gatineau and cv. Nova) to 118 mg/100 g fw (cv. Ville). The total anthocyanin content varied from close to 0 (yellow cultivars) to 51 mg/100 g fw (cv. Gatineau). The content of total phenolics varied from 192 (cv. Gatineau) to 359 mg/100 g fw (cv. Ville). In addition, environment had a significant effect on the content of quercetin. Thus, breeding material should be evaluated for their potential health benefits over several regions in northern raspberry breeding.     

蔗糖及一些渗透剂对紫草培养细胞中红色素释放的效应

紫草(Perilla frutescens)悬浮培养细胞在胞内产生并积蓄花青苷(红色素)。通过实验发现用一些渗透剂如甲苯、氯仿、聚乙二醇辛基苯基醚(Triton X—100)、二甲亚砜(dimethylsulfoxide)、醋酸和乙醇等处理培养细胞,可使细胞内的红色素释放出来。培养的紫草细胞一般在含3%蔗糖浓度的LS培养基中生长,当提高蔗糖浓度至4.0%～4.5%时,细胞生长量及色素的产量均有增加。实验结果表明,蔗糖浓度的提高不仅可以增加碳源,而且更重要的原因还可能是蔗糖渗透压的影响,在高糖浓度也即高渗透压下,细胞红色素的渗透性有所增加。     

In vivo antioxidant,hypoglycemic, and anti-tumor activities of anthocyanin extracts from purple sweet potato

Anthocyanin from purple sweet potato (PSP) extracted by microwave baking (MB) and acidified electrolyzed water (AEW) exhibited antioxidant activity. After further purification by macroporous AB-8 resin, the color value of PSP anthocyanin (PSPA) reached 30.15 with a total flavonoid concentration of 932.5 mg/g. The purified extracts had more potent antioxidant activities than the crude extracts. After continuously administering the PSP extracts to 12-mo-old mice for 1 mo, the anti-aging index of the experimental group was not significantly different from that of 5-mo-old mice. To a certain degree, PSPA was also effective for controlling plasma glucose levels in male Streptozocin (STZ)-treated diabetic mice. In addition, the extracts inhibited Sarcoma S180 cell growth in ICR mice. Mice consuming the PSP extracts formed significantly fewer and smaller sarcomas than mice consuming the control diets. The highest inhibition rate was 69.03%. These results suggest that anthocyanin extracts from PSP not only exert strong antioxidant effects in vitro, but also had anti-aging, anti-hyperglycemic, and anti-tumor activities.     

紫肉甘薯中氯化花青素含量测定方法的建立

目的建立用液相色谱法测定紫肉甘薯中氯化花青素含量的方法。方法高效液相色谱法,用Kromasil C18柱(4.6mm×250mm,5μm);流动相:乙腈-水-冰醋酸(15∶76.5∶8.5);紫外检测波长:530nm。结果建立了高效液相色谱法测定氯化花青素含量的方法;氯化花青素的线性范围为0～0.2089μg(r=0.9998);平均回收率为97.95%,RSD=1.0%。结论方法简单、快速,结果准确。     

Cyanidin-3-O-β-glucoside protects primary mouse hepatocytes against high glucose-induced apoptosis by modulating mitochondrial dysfunction and the PI3K/Akt pathway

Apoptosis is an early event of steatohepatitis in non-alcoholic fatty liver disease (NAFLD), and an increase in oxidative stress induced by hyperglycemia has been linked to an acceleration of apoptosis in hepatocytes. Cyanidin-3-O-β-glucoside (C3G), a classic anthocyanin, has been reported to reduce oxidative stress and attenuate non-alcoholic steatohepatitis in mice. In this study, we evaluated the toxicity of high glucose in primary hepatocytes of mice fed with a high fat diet and amelioration of this toxicity by C3G. Incubation of hepatocytes with 35 mM glucose for 12 h resulted in a significant decrease in cell viability and increase in apoptotic cell death. Furthermore, hyperglycemia-induced mitochondrial depolarization was accompanied by the release of cytochrome c and altered expression of Bax and Bcl-2, suggesting a mitochondria-mediated apoptotic mode of cell death. Pre-incubation with 50 μM C3G induced changes associated with better cell survival and function, including a reduction in reactive species generation, improvement of mitochondrial membrane potential, inactivation of caspase-3 and -9, and down-regulation of the pro-apoptotic Bax protein. We further investigated the role of the phosphatidylinositol 3-kinase (PI3K)/Akt and mitogen-activated protein kinases (MAPKs) pathways with respect to the anti-apoptotic action of C3G, and our results showed that C3G could activate Akt. Additionally, C3G inactivated c-Jun N-terminal protein kinase (JNK), but not extracellular signal-regulated kinase or p38 MAPK, in glucose-stressed cells. Interestingly, JNK inhibitor enhanced the protective effect of C3G on cell survival. Our results suggest that anthocyanin C3G may exhibit hepatoprotective potential against NAFLD by promoting functional integrity and survival of hepatocytes.     

玉米紫色植株色素体外诱导人肺腺癌A549细胞凋亡的初步研究

[目的]研究玉米紫色植株色素(PMPP)对人肺腺癌A549细胞增殖、凋亡、细胞周期的影响。[方法]MTT法比较不同浓度的PMPP对体外培养的肺癌细胞增殖的影响,流式细胞术检测细胞凋亡率和细胞周期,同时应用倒置显微镜观察凋亡细胞的形态学特征。[结果]不同浓度PMPP溶液对A549细胞的增殖均有抑制作用,浓度为50mg/ml时的抑制率最大,约为85.35%。形态学表现为单位视野内细胞数量明显减少,细胞间隙增大,细胞体积明显缩小,细胞失去原有的形态,胞体皱缩变圆,出现膜发泡现象。流式细胞术结果表明,当PMPP浓度为40mg/ml时,处于S期的肿瘤细胞增多,凋亡率为41.52%。[结论]玉米紫色植株色素可通过诱导部分细胞凋亡抑制人肺腺癌A549细胞增殖。     

Neuroprotective Effect of Anthocyanin on Experimental Traumatic Spinal Cord Injury

Objective

We investigated the neuroprotective effect of anthocyanin, oxygen radical scavenger extracted from raspberries, after traumatic spinal cord injury (SCI) in rats.

Methods

The animals were divided into two groups : the vehicle-treated group (control group, n=20) received an oral administration of normal saline via stomach intubation immediately after SCI, and the anthocyanin-treated group (AT group, n=20) received 400 mg/kg of cyanidin 3-O-β-glucoside (C3G) in the same way. We compared the neurological functions, superoxide expressions and lesion volumes in two groups.

Results

At 14 days after SCI, the AT group showed significant improvement of the BBB score by 16.7±3.4%, platform hang by 40.0±9.1% and hind foot bar grab by 30.8±8.4% (p<0.05 in all outcomes). The degree of superoxide expression, represented by the ratio of red fluorescence intensity, was significantly lower in the AT group (0.98±0.38) than the control group (1.34±0.24) (p<0.05). The lesion volume in lesion periphery was 32.1±2.4 µL in the control and 24.5±2.3 µL in the AT group, respectively (p<0.05), and the motor neuron cell number of the anterior horn in lesion periphery was 8.3±5.1 cells/HPF in the control and 13.4±6.3 cells/HPF in the AT group, respectively (p<0.05).

Conclusion

Anthocyanin seemed to reduce lesion volume and neuronal loss by its antioxidant effect and these resulted in improved functional recovery.