Extraction Characteristics of Anthocyanins from Preliminarily-processed Products of Purple Sweet Potatoes during the Gelatinization Process

Objective] This study aimed to investigate the method for efficient utilization and development of purple sweet potatoes. [Method] Purple sweet potatoes were dried at two specific temperatures and prepared into preliminarily-processed products for gelatinization simulation to analyze the extraction amount of anthocyanins from gelatinized samples at different gelatinization stages. [Result] During the gelatinization process, the extraction rate of anthocyanins from purple sweet potato samples reached the highest as the temperature rised from 90 ℃ to 95 ℃,and the extraction amount of anthocyanins reached the maximum at 15 min postheat preservation at 95 ℃. Purple sweet potato samples dried at 60 ℃ exhibited larger retention amount, larger maximum extraction amount and higher maximum extraction rate of anthocyanins compared with those dried at 110 ℃. [Conclusion] Drying at low temperatures and appropriately shortening the initial gelatinization stage below 90 ℃ is conducive to the retention and extraction of anthocyanins from purple sweet potatoes.

Genome-wide Analysis of MYB Gene Family in Potato Provides Insights into Tissue-specific Regulation of Anthocyanin Biosynthesis

The MYB transcription factor is one of the largest gene families in plants,playing an important role in regulating plant growth,development,response to stress,senescence,and especially the anthocyanin biosynthesis.In this study,A total of 217 MYB genes,including 901R-MYBs,124 R2R3-MYBs,and 3 R1R2R3-MYBs have been identified from the potato genome.The 1R-MYB and R2R3-MYB family members could be divided into 20 and 35 subgroups respectively.Analysis of gene structure and protein motifs revealed that members within the same subgroup presented similar exon/intron and motif organization,further supporting the results of phylogenetic analysis.Potato is an ideal plant to reveal the tissue-specific anthocyanins biosynthesis regulated by MYB,as the anthocyanins could be accumulated in different tissues,showing colorful phenotypes.Five pairs of colored and colorless tissues,stigma,petal,stem,leaf,and tuber flesh,were applied to the transcriptomic analysis.A total of 70 MYB genes were found to be differentially expressed between colored and colorless tissues,and these differentially expressed genes were suspected to regulate the biosynthesis of anthocyanin of different tissues.Co-expression analysis identified numerous potential interactive regulators of anthocyanins biosynthesis,involving 39 MYBs,24 bHLHs,2 WD-repeats,and 29 biosynthesis genes.Genome-wide association study(GWAS)of tuber flesh color revealed amajor signal at the end of Chromosome 10,which was co-localized with reported I gene(StMYB88),controlling tuber peel color.Analyses of DEGs(Differentially Expression Genes)revealed that both StMYB88 and StMYB89 were closely related to regulating anthocyanin biosynthesis of tuber flesh.This work offers a comprehensive overview of the MYB family in potato and will lay a foundation for the functional validation of these genes in the tissue-specific regulation of anthocyanin biosynthesis.

Optimization of Extraction Process of Anthocyanins from Selenium-enriched Purple Potato by Response Surface Methodology

Ultrasound-assisted extraction method was applied to extract the anthocyanins from selenium-enriched purple potato,and the optimum extraction conditions for anthocyanins in selenium-enriched purple potato were obtained by response surface methodology:the phosphoric acid concentration of 1.0%,the solid-liquid ratio at 5,and the extraction time of 19 min.Under these conditions,the yield of anthocyanins in selenium-enriched purple potato reached(0.409±0.010)mg/g(RSD=2.51%,n=3).The extraction of anthocyanins from selenium-rich fresh purple potato with dilute phosphoric acid has the advantages of less acid consumption and good extraction effect.

Coronatine Induces an Accumulation of Anthocyanin and Starch in Purple-fleshed Sweetpotato(Ipomoea batatas Lam.)

[Objective] The objective of this research was to examine the effects of COR on anthocyanin and starch content in storage roots of two PFS genotypes, and to explore the relationships between anthocyanin synthesis and starch accumula- tion. [Method] A field experiment was carried out to determine the changes in yielc components, yield, contents of anthocyanin and starch, activities of phenylalanine ammonia-lyase （PAL） and adenosine 5-diphosphate glucose pyrophosphorylase （AG- Pase） in two genotypes of PFS （Ipomoea batatas L., var. ＇Ayamurasaki＇ and ＇Jishu18＇）. [Result] The application of COR significantly increased starch and antho- cyanin content in storage roots of Jishu18 across developmental stages by inducing the activities of PAL and AGPase, and finally enhanced yield by promoting fresh weight of storage roots. Ayamurasaki was insensitive to treatment with COR al- though its PAL activity temporally increased. The starch and anthocyanin content of Aya, and the anthocyanin content of Jishu18 increased progressively across devel- opmental stages with or without COR application, but the starch content of Jishu18 increased initially, then decreased before increasing again without application of COR. Treatment with COR reduced downward trend of starch accumulation in Jishu18. Thus, the effect of COR on accumulation of anthocyanin and starch in storage roots of PFS differs according to genotypes. [Conclusion] The application of 0.05 μmol/L COR may increase starch and anthocyanin content in PFS genotypes with lower starch and anthocyanin content in storage roots.

Regulation of Anthocyanin during Storage Root Development Stage in Sweet Potato(Ipomoea batatas(L.) Lam.)

Anthocyanin accumulation during storage root development in purple-fleshed sweet potato was analyzed by detection of anthocyanin concentration, accumulation rate and the expression pattern of anthocyanin biosynthetic genes by semi-quantitative RT-PCR. Anthocyanin concentration in sweet potato cvs Jishu 18 and Ayamurasaki increased steadily during storage root development stage. The accumulation rate in two genotypes peaked at 50 to 65 d after transplanting, and then declined rapidly. During storage root development of Ayamurasaki, the anthocyanin biosynthesis gene, IbCHS, was constitutively expressed, the genes IbF3H, IbDFR, IbANS were induced steadily, reaching a maximum at the later stage of root thickening, and IbPAL steadily decreased. Therefore, the mechanism of anthocyanin accumulation differed between the two cultivars, and anthocyanin biosynthesis was regulated through regulation of its synthetic enzymes.

试管微环境对马铃薯‘GSAP-H’愈伤组织花青素含量的影响

【目的】为获得愈伤组织生长及花青素积累的最佳培养条件.【方法】针对马铃薯"GSAP-H"试管苗茎叶诱导出的紫色愈伤组织进行了外源激素、糖源、不同N素比例、光温和pH等条件的研究.【结果】随NAA、2,4-D浓度的增加,愈伤组织快速生长,花青素含量呈先升后降的趋势,于1.5mg/L 2,4-D和1.0mg/L NAA浓度下达到高峰,分别为863.15、880.65nmol/g;高浓度BAP不利于愈伤组织的生长,但花青素含量在4mg/L BAP下达到高峰,为848.745nmol/g.蔗糖是花青素生产的最好碳源,45g/L蔗糖下的愈伤组织生长最快且花青素含量最高(887.035nmol/g);培养基中NO_3^-与NH_4^+比例为3:1时,愈伤组织花青素含量最高(895.54nmol/g).此外,全光照利于花青素产量的提高.pH 4.8及25℃的培养条件可明显促进愈伤组织花青素的积累.【结论】研究结果将为利用紫色马铃薯愈伤组织进行工厂化生产花青素奠定一定基础.

Sensory Evaluation of Pigmented Flesh Potatoes (<i>Solanum tuberosum</i>L.)

Pigmented potato cultivars were ranked by a consumer panel for overall acceptance, and acceptance of aroma, appearance, and flavor. Potatoes were analyzed for total phenolics, anthocyanins and carotenoids. Concentrations of total phenolics in yellow and purple potato cultivars were 2-fold greater (P P

Flesh Color Diversity of Sweet Potato: An Overview of the Composition, Functions, Biosynthesis, and Gene Regulation of the Major Pigments

Sweet potato is a multifunctional root crop and a source of food with many essential nutrients and bioactive compounds.Variations in the flesh color of the diverse sweet potato varieties are attributed to the different phytochemicals and natural pigments they produce.Among them,carotenoids and anthocyanins are the main pigments known for their antioxidant properties which provide a host of health benefits,hence,regarded as a major component of the human diet.In this review,we provide an overview of the major pigments in sweet potato with much emphasis on their biosynthesis,functions,and regulatory control.More-over,current findings on the molecular mechanisms underlying the biosynthesis and accumulation of carotenoids and anthocyanins in sweet potato are discussed.Insights into the composition,biosynthesis,and regulatory control of these major pigments will further advance the biofortification of sweet potato and provide a reference for breeding carotenoid-and anthocyanin-rich varieties.

Effect of Different Solvents on the Extraction of Phytochemicals in Colored Potatoes

Colored potatoes are an interesting alternative to the traditional, white-creamed potatoes, due to their high phytochemical content, which have been proved to have antioxidative properties. The extraction of polyphenols is highly dependent on using the appropriate solvent systems. Therefore, polyphenol extraction in colored potatoes [Vermillion Fingerling (VF);Jester Potato (JP);Magic Molly (MM);Blue Belle (BB);All Blue (AB)] using different solvents [Solvent A (24% water, 67% ethanol 9% acetic acid);Solvent B (5% acetic acid);and Solvent C (95% water, 5% acetic acid, 0.5 g sodium bisulfate)] may have significant effects on extraction efficiency and phytochemical content. Total phenolic content (TPC), Total flavonoid content (TFC), Total anthocyanin content (TAC) and antioxidant activities [Trolox Equivalent Antioxidant Capacity (TEAC) and Ferric reducing-antioxidant power (FRAP)] were determined. Solvent A extracted significantly (p < 0.05) higher TPC from BB (13.93 mg GAE/100g) compared to the other solvents. VF and JP displayed higher TFC (14.53 and 19.46 mg CE/100g, respectively) when Solvent C was utilized. VF and JP extracts with Solvent C displayed the highest FRAP value compared to Solvent B. MM displayed the highest TAC using Solvent A and C. Potato variety resulted in high variability in polyphenols content and antioxidant activity. The utilization of colored potatoes or extracts in the food industry could provide innovative products and a functional alternative to the traditional.

Protein and Phenolic Contents and Antioxidant Activities of 14 Early Maturing Potatoes as Affected by Processing

The effects of processing and genotype (fourteen early potato varieties) were evaluated for their phytochemicals, total phenolics (TPC), total flavonoids (TFC), total anthocyanins (TAC), antioxidant activities measured by ORAC, FRAP and DPPH assays and protein content. While all these profiles were highly dependent on the potato variety and processing, F09085, F10090, French Fingerlings, Purple Fiesta, Red Thumb, Ciklamen and Norland were identified as nutritionally rich in phytochemicals such as TPC, TFC, TAC, higher antioxidant capacities and protein (p p p < 0.0001).

4个彩色马铃薯品种花青素组分和含量比较分析

为明确彩色马铃薯新品种闽彩薯1号、闽彩薯2号、闽彩薯3号和闽彩薯4号的块茎花青素组分和含量的差异,为新品种选育及花青素开发应用提供依据。利用高效液相色谱与质谱联用技术,进行了块茎花青素组分的定性与比较分析。结果表明,4个彩色品种共含有14种花青素单体组成,其中闽彩薯1号含有其中的6种组分,闽彩薯2号含有其中的9种组分,闽彩薯3号含有其中的10种组分,3个紫肉色马铃薯花青素组分主要是矮牵牛素3-p-香豆酰基芸香糖苷-5-葡萄糖苷和芍药素3-p-香豆酰基芸香糖苷-5-葡萄糖苷。闽彩薯4号含有5种花青素组分,主要组分为矢车菊素3-芸香糖苷和天竺葵素3-p-香豆酰基芸香糖苷-5-葡糖苷,紫肉色马铃薯花青素组分与红肉色马铃薯青素组分具有明显差异。4个彩色马铃薯花青薯含量分别为139.77、95.48、78.08、67.25 mg/100 g FW,品种之间具有显著差异。同时,这4个彩色马铃薯组分含有全部6种花青素基本苷元,且花青素结构较为稳定,可作为重要的天然色素的原料及杂交育种的亲本材料。

紫薯粉对莜麦饼干品质的影响

通过添加一定比例的紫薯粉改良莜麦饼干配方,从而提升饼干的感官评价、质构、营养成分含量等指标。通过单因素和正交试验,考察紫薯粉和莜麦粉质量比、黄油添加量以及白砂糖添加量对饼干品质的影响,进而采用验证试验比较改良前后莜麦饼干品质,并通过高分辨率质谱分析添加紫薯粉后莜麦饼干中花色苷含量的变化。根据产品的感官评分以及质构特性,得出改良后的紫薯⁃莜麦饼干的最佳配方为紫薯粉和莜麦粉质量比60∶140、黄油添加量100 g、白砂糖添加量80 g。添加紫薯粉后的莜麦饼干颜色均匀,莜麦的色泽得到改善,质构评分良好,还增添紫薯特殊的香气和风味,感官评分为84.9。改良后的紫薯⁃莜麦饼干中鉴定出20种花色苷,花色苷总含量为0.18 mg/g。

马铃薯ARM基因家族的全基因组鉴定及表达分析

ARM蛋白重复序列(Armadillo repeats)广泛存在于高等植物中,它们参与多种细胞过程,如信号转导、核转运以及对多种生物/非生物胁迫的响应。本研究在马铃薯(Solanum tuberosum L.)全基因组水平下鉴定出了54个马铃薯ARM基因家族成员(StARMs),它们不均匀的分布在12条染色体上。根据其蛋白结构和系统发育特征,将54个StARMs分为3个亚家族。片段重复事件在马铃薯ARM基因家族的扩展中起主要作用。共线性分析发现,StARMs与番茄(Solanum lycopersicum)、拟南芥(Arabidopsis)、甘蓝(Brassica oleracea)、水稻(Oryza sativa)、玉米(Zea mays)分别有51对、17对、25对、6对和10对直系同源基因,这些基因均在纯化选择下进化。RNA-seq数据分析发现,4个StARM基因在匍匐茎中特异表达,2个StARM基因在根和心皮中特异表达,1个StARM基因在块茎中特异表,还有一些StARM基因参与了马铃薯对生物/非生物胁迫的响应。此外,本研究对3个不同颜色马铃薯块茎组织(薯皮和薯肉)进行了RNA-seq测序,分析了54个StARMs在不同颜色马铃薯块茎组织中的表达模式,并利用qPCR分析了StARMs在3个不同颜色块茎杂交子代薯肉中的相对表达量,筛选出了4个可能参与马铃薯块茎花色素苷生物合成的候选基因。本研究为进一步了解StARM基因家族的特征,深入分析StARM基因在马铃薯抵御生物/非生物胁迫和调控块茎花色素苷生物合成中的功能提供了理论依据。

紫色马铃薯糕加工工艺参数优化

以低筋面粉和紫色马铃薯为主要原料制作紫色马铃薯糕,采用单因素和正交试验优化紫色马铃薯糕的最佳加工工艺参数,并以感官评分为指标,对该工艺参数下制作的紫色马铃薯糕进行客观评价。结果表明,制作紫色马铃薯糕的最佳工艺参数为紫色马铃薯与低筋面粉总重200 g,其比例35∶65,绵白糖添加量35 g,酵母粉添加量1.5 g,蒸制时间20 min。该工艺条件下制作的紫色马铃薯糕色泽艳丽且均匀,呈天然紫色,松软有弹性,外形完整饱满,口感细腻,富含花青素,具有较高的营养价值,适合婴幼儿及中老年人食用,极大丰富了糕点类食物的市场多样性,具有较高的推广价值。

含紫薯花青素的槟榔芋淀粉薄膜性能及其应用

开发含紫薯花青素(PSPA)并可生物降解的槟榔芋淀粉薄膜(TSF),并研究其光学性能、厚度、含水率、水溶性、颜色、总酚含量、抗氧化活性、红外光谱和微观结构等性能,初步探讨TSF对鲜切莴笋、鱼肉和猪肉储存过程中新鲜度的指示作用。研究表明TSF的紫外-可见光谱和PSPA溶液的光谱变化规律是一致的,表明PSPA与槟榔芋淀粉具有良好的成膜机制。TSF厚度适中,含水率为39.17%,水溶性为36.93%;TSF的DPPH清除率达到94%,表明TSF的抗氧化活性高。将TSF应用于鲜切莴笋、鱼肉和猪肉的新鲜度监测,TSF先呈现淡紫色,随着时间推移,鲜切莴笋、鱼肉和猪肉逐渐腐败变质,48 h后,TSF在莴笋中呈现蓝紫色、猪肉中呈现浅绿色、鱼肉中呈现淡黄色。

超声波辅助提取黑薯皮中花青素的工艺研究

以黑薯皮为提取原料、酸化甲醇为提取溶剂,采用超声波辅助提取黑薯皮中的花青素。以花青素的提取率为考察指标,首先研究提取温度、料液比、超声功率、超声时间、酸化甲醇浓度等单因素对黑薯皮中花青素提取率的影响。在单因素研究的基础上采用正交实验法进行优化和组合,最终确定黑薯皮中花青素提取的最佳工艺条件如下:提取温度55℃、料液比1∶25(g:mL)、超声功率270 W、超声时间25 min、酸化甲醇浓度50%,在此条件下,黑薯皮中花青素的提取率为10.90%。研究还表明,影响黑薯皮中花青素提取率的因素顺序为:料液比>提取温度>酸化甲醇浓度>超声功率>超声时间。

紫马铃薯花色苷提取工艺优化及稳定性、抗氧化活性分析

以甜菜碱为氢键受体,有机酸、糖基和醇基分别为氢键供体制备天然绿色的低共熔溶剂,基于微波辅助提取法,通过单因素实验并结合响应面分析对紫马铃薯花色苷提取工艺进行优化。主要考察了微波时间、微波功率、溶剂含水量、溶剂摩尔比对紫马铃薯花色苷含量的影响。同时比较低共熔溶剂与常规溶剂提取对紫马铃薯花色苷在不同温度、光照条件下的稳定性,以及DPPH、ABTS^(+)、OH自由基清除率评价体外抗氧化能力。结果表明,以甜菜碱和柠檬酸制备酸性低共熔溶剂,摩尔比1:2.1,含水量为28.6%,在微波功率800 W,微波时间28 s条件下,紫马铃薯花色苷含量可达到228.658±1.241 mg/100 g,较常规提取工艺含量提高了56.92%。此外通过低共熔溶剂提取所得花色苷在不同光照、温度条件下稳定性均显著提高。其中太阳光对紫马铃薯花色苷影响最大,避光情况下低共熔溶剂提取花色苷保存率可达90%以上,常规溶剂提取花色苷保存率为82.78%,此外,花色苷含量也随着温度的增加不断降低,二者保存率均明显下降。抗氧化能力结果表明,低共熔溶剂提取所得花色苷抗氧化能力更强,其清除自由基能力IC_(50)值均小于常规溶剂提取。DPPH自由基清除能力IC_(50)值从45.95μg/mL降至41.54μg/mL;ABTS+自由基清除能力IC_(50)值从17.81μg/mL至11.30μg/mL;OH自由基清除能力IC_(50)值从162.00μg/mL至22.44μg/mL。因此紫色马铃薯花色苷含量、稳定性和抗氧化活性与其提取溶剂的选择密切相关,本提取工艺的研究为紫马铃薯花色苷的利用开发提供了新思路。

基于蓝莓花青素的新鲜度指示膜制备及性能研究

为提升pH指示膜的综合性能,以微晶纤维素(micro-crystalline cellulose,MCC)、马铃薯淀粉(potato starch,PS)、聚乙烯醇(polyvinyl alcohol,PVA)为原料,蓝莓花青素(blueberry anthocyanins,BA)为指示剂,采用流延法制备指示膜,对指示膜的性能进行分析。结果表明,当BA、MCC、PS和PVA的质量比为0.3:0.2:3:0.3时,微晶纤维素提高了薄膜的拉伸强度(1.59 MPa至2.16 MPa)、断裂伸长率(35.83%至38.24%)、杨氏模量(8.25 GPa至25.65 GPa),降低了薄膜的含水率(34.85%至33.23%)和吸水率(122.97%至110.36%)。蓝莓花青素提高了薄膜的机械性能、阻隔性能,降低了耐水性,且与膜中各基质融合良好,指示膜结构均匀、致密。拉伸强度和杨氏模量分别升至2.19 MPa和37.12 GPa;透水率、含水率和吸水率分别降至1.45×10^(-12) g·cm/(cm^(2)·s·Pa)、30.7%和87.52%。蓝莓花青素还赋予薄膜pH敏感性。在不同pH环境中,指示膜与花青素的颜色变化趋势一致,色差可视;同时环境稳定性佳,在不同温度和光照条件下,指示膜的颜色稳定超过14 d(ΔE≤2)。研究结果可为蓝莓花青素指示膜的制备提供参考。

彩色马铃薯花青素合成相关ERF基因筛选及表达分析

【目的】乙烯响应因子(ethylene responsive factor,ERF)是一类重要的转录因子,参与调控植物花青素的生物合成。筛选可能参与调控马铃薯块茎花青素合成的StERFs基因,为开展彩色马铃薯花青素相关StERFs基因功能研究奠定基础。【方法】利用生物信息学方法对其理化性质、亚细胞定位、保守基序、进化关系、蛋白质二级结构、启动子顺式作用元件及蛋白互作关系进行分析,同时采用RT-qPCR方法对不同颜色马铃薯薯肉中StERFs进行表达模式分析。【结果】基于不同颜色马铃薯块茎的转录组表达谱,获得7个差异表达ERF转录因子。7个StERFs属于亲水性蛋白,均预测定位于细胞核。Motif 1(RWLG)和Motif 2(YRG)是7个StERFs中共同的保守基序,属于AP2的结构域特征序列。StERFs基因启动子序列含有响应激素作用元件,以及响应防御与胁迫、低温和光照等的顺式作用元件。7个StERFs在紫色薯肉中表达量显著高于黄色薯肉,其中StERF72和StERF110与已知的花青素相关ERFs(IbERF71和PyERF3)亲缘关系较近,且7个StERFs与56个转录因子存在蛋白互作关系。【结论】7个StERFs基因可能参与调控马铃薯块茎中花青素的合成,其中StERF72和StERF110可作为候选基因进一步验证其功能。

酸性条件下小麦低聚肽增强紫薯花色苷抗氧化性的研究

在pH4.0酸性条件下,添加25~100g/L的小麦低聚肽(WOPs)虽降低了紫薯花色苷(PSPAs)的热稳定性,但两者相互作用增强了其抗氧化能力,并随着其添加量的增加而增大。当添加量为100g/L时,PSPAs溶液在体外模拟消化后的DPPH、ABTS自由基清除能力和总抗氧化能力(FRAP)分别提高了1.5倍、34倍和34%,且分别在37℃和45℃贮藏7d后,其抗氧化能力没有出现显著性降低,相比于单独的PSPAs具有更强的生物活性以及更高的稳定性。紫外光谱和荧光光谱表明在实验浓度下,PSPAs可以引起WOPs特定波长下吸收峰的红移和荧光猝灭,证明WOPs和PSPAs之间存在相互作用。综上可知,WOPs具有应用于酸性PSPAs饮料开发的潜力。