Diacylated anthocyanins from purple sweet potato (Ipomoeabatatas L.) attenuate hyperglycemia and hyperuricemia in mice induced by a high-fructose/high-fat diet / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Studies have shown that targeting xanthine oxidase (XO) can be a feasible treatment for fructose-induced hyperuricemia and hyperglycemia. This study aimed to evaluate the dual regulatory effects and molecular mechanisms of diacylated anthocyanins from purple sweet potato (diacylated AF-PSPs) on hyperglycemia and hyperuricemia induced by a high-fructose/high-fat diet. The body weight, organ index, serum biochemical indexes, and liver antioxidant indexes of mice were measured, and the kidneys were observed in pathological sections. The relative expression levels of messenger RNAs (mRNAs) of fructose metabolism pathway enzymes in kidney were detected by fluorescent real-time quantitative polymerase chain (qPCR) reaction technique, and the expression of renal transporter protein and inflammatory factor pathway protein was determined by immunohistochemistry (IHC) technique. Results showed that diacylated AF-PSPs alleviated hyperuricemia in mice, and that this effect might be related to the regulation of liver XO activity, lipid accumulation, and relevant renal transporters. Diacylated AF-PSPs reduced body weight and relieved lipid metabolism disorder, liver lipid accumulation, and liver oxidative stress, thereby enhancing insulin utilization and sensitivity, lowering blood sugar, and reducing hyperglycemia in mice. Also, diacylated AF-PSPs restored mRNA levels related to renal fructose metabolism, and reduced kidney injury and inflammation. This study provided experimental evidence for the mechanisms of dual regulation of blood glucose and uric acid (UA) by diacylated AF-PSPs and their utilization as functional foods in the management of metabolic syndrome.

Antifungal activity of selected plant extracts against Curvularia sp. infecting local purple sweet potato (Ipomoea batatas)

Aims@#The present study was designed to evaluate in vitro antifungal activity of plant extracts against Curvularia sp., a causative agent of leaf blotch in local purple sweet potato crops. @*Methodology and results@#The plants were selected on the basis of commonly used traditional remedies. Various dilutions, 1/2, 1/4, 1/6, 1/8 and 1/10 of black pepper, garden croton, garlic, tobacco and turmeric extracts were used for screening. The lesion characteristics on purple sweet potato leaves were collected from plots in MARDI Bachok. The “poisoning agar technique method” was used to get the antifungal activity. The results of antifungal activities were reported in terms of inhibition of mycelial growth of the test fungus. Out of five types of plant extracts used, only garlic and tobacco showed significantly high antifungal activity against the test pathogen based on poisoned food technique. Garlic extract showed complete inhibition (100%) at 1/2 dilution and more than 94% growth inhibition at concentrations as low as 1/10 dilution after seven days of incubation. However, black pepper and turmeric extracts showed moderate inhibition (20-70%) whereas, no inhibition was recorded in 1/8 and 1/10 dilution of garden croton extract. @*Conclusion, significance and impact of study@#Our findings suggested that garlic extract is the most potential antifungal agent against Curvularia sp. and can be used as bio-fungicide thus would reduce the dependency on synthetic fungicides by farmers.

Potential inhibition of glycation and free radical scavenging activities of purple sweet potato extracts / Potencial inibição da glicação e sequestro de radicais livres de extratos de batata doce roxa

Purple sweet potato (PSP) contains antioxidant compounds and it can be used to prevent oxidative damage to cellular components of human body. The research purpose is to find out the potential of PSP extract on inhibiting glycation process and free radicals scavenging activities. Purple sweet potato was extracted using ethanol 25, 50, and 75% (PSP25, PSP50, PSP75) and then it was analyzed for free radical scavenging activities and antiglycation in forming advanced glycation end products (AGEs) using spectrophotometric method. Then all the collected data were examined with one-way ANOVA (p<0.05). The results showed that PSP extract has antioxidant activities and antiglycation properties.Based on IC50 values, PSP75 extract has a lower IC50 value compared to PSP25 and PSP50 (P <0.05) and has better activity in scavenging DPPH, hydroxyl, and superoxide radicals. This potentiality was shown by the IC50 value of each PSP extract. The value of IC50 of scavenging DPPH radical acitivity for PSP25, PSP50, PSP75 extracts was respectively 281.08, 254.94, and 241.30 µg/mL. The value of IC50 scavenging hydroxyl radicals was respectively 1.03, 088, and 0,79 mg/mL, and the IC50 value of scavenging radicals of superoxide anion was respectively 1.10, 0.97, and 0.82 mg/mL. The absorbance value of PSP75 in the BNT test and Fluorescence intensity are lower than PSP25 and PSP50, so that PSP75 extract is better at inhibiting glycation reaction.It can be concluded that the PSP extract has the potential in the inhibition of the glycation reaction and in the activity of elimination of free radicals (DPPH, hydroxyl, and superoxide radicals).

Batata-doce roxa (PSP) contém compostos antioxidantes e pode ser usada para prevenir o dano oxidativo aos componentes celulares do corpo humano. O objetivo da pesquisa é descobrir o potencial do extrato de PSP na inibição do processo de glicação e atividades de eliminação de radicais livres. A batata-doce roxa foi extraída usando etanol 25, 50 e 75% (PSP25, PSP50, PSP75) e, em seguida, foi analisada quanto a atividades de eliminação de radicais livres e antiglicação na formação de produtos finais de glicação avançada (AGEs) usando método espectrofotométrico. Em seguida, todos os dados coletados foram examinados com uma análise de variância simples (one-way ANOVA) (p <0,05). Os resultados mostraram que o extrato de PSP possui atividade antioxidante e propriedades antiglicantes. O extrato de PSP75 apresentou a maior atividade de eliminação dos radicais DPPH, hidroxila e superóxido significativamente maiores (P <0,05) que os extratos PSP25 e PSP50. Esta potencialidade foi demonstrada pelo valor de IC50 de cada extrato de PSP. O valor de IC50 da atividade de eliminação do radical DPPH para os extractos PSP25, PSP50, PSP75 foi respectivamente de 281,08, 254,94 e 241,30 g/mL. O valor IC50 dos sequestrantes dos radicais hidroxila foi, respectivamente, de 1,03, 088 e 0,79 mg/mL, e o valor de IC50 dos radicais sequestrantes do superóxido foi, respectivamente, 1,10, 0,97 e 0,82 mg/mL. Como antiglicante, o extrato de PSP75 tem uma capacidade melhor do que PSP25 e PSP50 em inibir produtos de AGEs. Pode-se concluir que o extrato etanólico PSP75 possui alta atividade antioxidante e potencial como antiglicante.

Screening of Active Fractions for Purple Sweet Potato Flavonoids with Insulin Resistance Improving Ability of L6 Cells / 中国药师

Objective:To screen the active fractions from purple sweet potatoes containing flavonoids with insulin resistance impro -ving ability.Methods:L6 cell model with insulin resistance was established .The extracting solutions with different polarity of purple sweet potato flavonoids were used to affect the model .The residual glucose concentration in insulin resistant L 6 cells was observed and compared before and after the intervention .Results:The residual glucose concentration of total flavonoids extracting solution , butanol extracting solution at middle and high dose , and chloroform extracting solution at all doses of purple sweet potato were lower than that of IR group (P<0.05).Conclusion:The total flavonoids extract, chloroform extracting solution and butanol extracting solution of purple sweet potato can improve insulin resistance in L 6 cells.

Effects of Purple Sweet Potato Flavonoids in Extracts with Different Polarity on IR-HepG2 Cells / 中国药师

Objective:To investigate the effects of purple sweet potato flavonoids (PSPF)in the extracts with different polarity on the insulin resistant HepG2 (IR-HepG2) cells.Methods: PSPF in the extracts with different polarity was used to intervene the IR-HepG2 model, and the remaining glucose concentration in the IR-HepG2 group and PSPF intervention groups was compared .Results:The remaining glucose concentration in PSPF intervention group , PSPF with chloroform as the extracting solvent at high , medium and low dose of PSPF , and PSPF with butanol as the extracting solvent at high and medium dose of PSPF was obviously lower than that in the IR-HepG2 group(P<0.05).Conclusion:PSPF, the chloroform extract of PSPF and the butanol extract of PSPF can enhance the consumption of glucose in IR-HepG2 cells.

Effects of an aqueous extract of purple sweet potato on nonalcoholic fatty liver in high fat/cholesterol-fed mice / 한국영양학회지

PURPOSE: Anthocyanins from purple sweet potato (PSP) have been investigated in vitro and in animals and found to have a protective effect against oxidative hepatic damage. In this study, we investigated that aqueous extract of PSP can ameliorate the dysfunction of lipid metabolism in mice fed a high fat/cholesterol diet. METHODS: Forty C57BL/6J mice were randomly divided into 5 groups (n = 8) and fed one of the following diets for 8 weeks; normal fat (NF) diet; high fat/cholesterol (HFC) diet; HFC with 1.25% PSP (HFPL) diet; HFC with 2.5% PSP (HFPM) diet; HFC with 5% PSP (HFPH) diet. RESULTS: Non-alcoholic fatty liver was manifested in the HFC group by showing increased levels in plasma alanine aminotransferase (ALT) activity, total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C), increased level of TC and presence of many large lipid droplets in the liver, and increased fat cell size in the HFC group compared with the NF group. However, administration of HFC induced a significant decrease in food intake, resulting in decrease in fat mass. Coadministration of PSP did not lead to reversal of body weight changes, ALT activity, and lipid levels in plasma and the liver, but suppressed excess enlargement of the fat cell size through increasing carnitine palmitoyltransferase-1 (CPT-1) gene expression in the liver. Accordingly, the number of fat droplets in the liver was reduced in PSP administered groups. CONCLUSION: Taken together, these results suggest that PSP may have a protective effect on the dysfunction of lipid metabolism. Conduct of further studies on the coordinated regulation of PSP for lipid metabolic homeostasis at the liver-adipose tissue axis is needed.

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.

Optimization of Brown Rice Cookies using Purple Sweet Potato

The aim of this study was to use purple sweet potato powder to develop a recipe for a nutritional cookie with an optimal composition of ingredients and texture, in order to acquire strong preference responses by all age groups in sensory tests. Wheat flour was partially substituted with purple sweet potato powder to reduce the wheat flour content of the cookies. Measurements were made and analyzed according to the Response Surface Methodology technique, which showed 16 experimental points including 3 replicates for the purple sweet potato powder, sugar, and butter. The compositional and functional properties of the sample were measured, and the values obtained were applied to a mathematical model. A canonical form and perturbation plot showed the influence of each ingredient on the final product mixture. The results of sensory evaluations showed very significant values for flavor (P<0.0071), texture (P<0.0306), taste (P<0.0190), and overall quality (P<0.0142). Instrumental analysis showed significant values for hardness (P<0.0027), yellowness (P<0.0061) and spread ratio (P<0.0001). The optimal compositional ratios were determined to be 21.75 g for the purple sweet potato powder, 37.05 g for the sugar, and 60.59 g for the butter.

Determination of Anthocyanin Chloride in Purple Sweet Potato by HPLC / 中药新药与临床药理

Objective To develop a HPLC method for the determination of anthocyanin chloride in purple sweet potato.Methods The analysis was carried out by using Kromsail C18 column(4.6 mm? 250 mm,5 ? m).The mobile phase consists of acetonitrile-water-acetic acid(15 ∶ 76.5 ∶ 8.5).The wavelength of detection was at 530 nm.Results The linear range of anthocyanin was 0～ 0.208 9 ? g(r=0.999 8).The average recovery was 97.95 %(RSD=1.0 %,n=5).Conclusions This method is simple and reliable.