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Davide Risso Gabriella Morini Luca Pagani Andrea Quagliariello Cristina Giuliani Sara De Fanti Marco Sazzini Donata Luiselli Sergio Tofanelli 《Genes & nutrition》2014,9(3)
The demand for diet products is continuously increasing, together with that for natural food ingredients. Stevioside and other steviol glycosides extracted from the leaves of the plant Stevia rebaudiana Bertoni are the first natural high-potency sweeteners to be approved for consumption in the United States and the European Union. However, the sweetness of these compounds is generally accompanied by aversive sensations, such as bitter and off-tastes, which may constitute a limit to their consumption. Moreover, consumers’ differences in sensitivity to high-potency sweeteners are well known, as well as difficulties in characterizing their aftertaste. Recently, TAS2R4 and TAS2R14 have been identified as the receptors that mediate the bitter off-taste of steviol glycosides in vitro. In the present study, we demonstrate that TAS2R4 gene polymorphism rs2234001 and TAS2R14 gene polymorphism rs3741843 are functional for stevioside bitterness perception.
Electronic supplementary material
The online version of this article (doi:10.1007/s12263-014-0401-y) contains supplementary material, which is available to authorized users. 相似文献24.
以甜叶菊(Stevia rebaudiana Bertoni)茎段为外植体,采用L9(34)正交表对腋芽诱导培养基中的激素种类和浓度(0.0、0.1和0.2 ng·L-1NAA;0.0、0.5和1.0 mg·L-16-BA;0.000、0.005和0.010 mg·L-1TDZ)进行筛选;在此基础上对诱变过程中NaN3溶液的浓度(3、6和9 mmol·L-1)和处理时间(1、2、4和8h)进行比较,并初步筛选出最佳的NaN3诱变条件;采用聚丙烯酰胺凝胶电泳法(PAGE)对经上述NaN3诱变处理后培养5、10和15 d的试管苗POD同工酶酶谱的变化进行了分析.结果表明:在添加了不同激素组合的培养基上均能诱导出腋芽,但腋芽数和苗高有差异;经综合比较后可确定适宜于甜叶菊腋芽诱导的培养基为添加1.0 mg·L-16-BA和0.1 mg·L-1NAA的MS培养基(含5.0g·L-1琼脂粉和30g·L-1蔗糖,pH 6.0).经NaN3诱变处理后,茎段在腋芽诱导培养过程中的死亡率随NaN3浓度提高和处理时间延长逐渐增加,平均腋芽数和苗高则下降,且多数处理组试管苗矮化;根据半致死剂量确定的最佳NaN3诱变处理方法为将甜叶菊茎段置于9 mmol·L-1 NaN3溶液中浸泡4h.PAGE分析结果表明:甜叶菊诱变试管苗的POD同工酶谱均可分为a、b和c区,但在不同培养时间各处理组POD同工酶的条带数和活性有所变化.在培养5和10 d后各处理组诱变试管苗POD同工酶的活性和条带数量有明显差异,而在培养15 d后各处理组诱变试管苗POD同工酶活性有差异,但条带数量没有明显变化,表明用适宜浓度的NaN3进行诱变处理可导致甜叶菊试管苗短期的应激效应. 相似文献
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Stevioside 总被引:14,自引:0,他引:14
Geuns JM 《Phytochemistry》2003,64(5):913-921
Stevioside is a natural sweetener extracted from leaves of Stevia rebaudiana (Bertoni) Bertoni. The literature about Stevia, the occurrence of its sweeteners, their biosynthetic pathway and toxicological aspects are discussed. Injection experiments or perfusion experiments of organs are considered as not relevant for the use of Stevia or stevioside as food, and therefore these studies are not included in this review. The metabolism of stevioside is discussed in relation with the possible formation of steviol. Different mutagenicity studies as well as studies on carcinogenicity are discussed. Acute and subacute toxicity studies revealed a very low toxicity of Stevia and stevioside. Fertility and teratogenicity studies are discussed as well as the effects on the bio-availability of other nutrients in the diet. The conclusion is that Stevia and stevioside are safe when used as a sweetener. It is suited for both diabetics, and PKU patients, as well as for obese persons intending to lose weight by avoiding sugar supplements in the diet. No allergic reactions to it seem to exist. 相似文献
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在分化条件下甜菊愈伤组织分生区细胞超微结构研究 总被引:2,自引:0,他引:2
对甜菊(Steviarebaudiana)愈伤组织中尚未发生器官分化的分生细胞团进行了超微结构研究.结果表明,在器官分化条件下,愈伤组织中形成的分生区域的细胞体积小,细胞核大,核仁明显,且具核仁泡,部分细胞核中含有核内含物.大量小液泡分布在细胞的边周或散布于整个细胞中.液泡中通常含有陷入的细胞质成分和膜状物.部分液泡的形成与内质网膨大有密切关系.同时也观察到由内质网形成的多圈膜和双层膜包围细胞质成分的同心环结构.高尔基体及其小泡丰富,有时聚集分布在细胞某一区域.核糖体密集,有的聚集成多聚核糖体.因此,愈伤组织中分生区的细胞与分生组织中的液泡化和分裂的细胞类似.分生区细胞的另一明显特征是出现质膜内陷.推测这些超微结构特征可能反映了甜菊愈伤组织器官分化前的某些形态变化。 相似文献