Structure and physicochemical properties of polysaccharides from Poria cocos extracted by deep eutectic solvent

Glycoconjugate Journal - Poria cocos, a famous traditional Chinese medicine and a well-known food or food supplement, has shown therapeutic potential against cancer and the uneasiness of the mind....     

New data on the palaeobiology of the enigmatic yunnanozoans from the Chengjiang Biota,Lower Cambrian,China

Interpretation of the enigmatic soft‐bodied yunnanozoans from the Lower Cambrian (Stage 3, Series 2) Chengjiang Biota has remained controversial for decades because of their strange body plan and their variable taphonomic alteration. Proposed affinities have ranged from stem bilaterian to stem vertebrate. A study of over seven hundred slabs, many newly collected, from five sections at two localities demonstrates that yunnanozoans have sclerotized dorsal and axial segments, a body cavity, a unique feeding region and a coiled alimentary canal. Although two genera have been previously discriminated, all specimens have the same number of filamentous arches (seven pairs) and of ventral circular structures (four pairs); this indicates that Haikouella Chen, Huang and Li, 1999 is a junior synonym of Yunnanozoon Hou, Ramsköld and Bergström, 1991. Our analysis reveals new details of the putative pharyngeal pores of Yunnanozoon lividum, and although there are similarities with the gill slits of deuterostomes, the question of their homology remains moot. The filamentous arches and their supporting rods were probably sclerotized and represent a specialized feeding structure. Yunnanozoans exhibit characters that are open to a number of alternative interpretations of putative homology, encompassing comparisons with deuterostomes and protostomes (including members of the Platyzoa). Given their unique features, and the current lack of secure homologies, the affinities of yunnanozoans should continue to be considered in a wider bilaterian context.     

Enantioselective Degradation of Indoxacarb From Different Commercial Formulations Applied to Tea

The stereoselective degradation of indoxacarb enriched with (+)‐S‐indoxacarb (S/R:70/30) was investigated in three typical green teas. A convenient and precise chiral method was developed and validated for measuring indoxacarb enantiomers in green tea. The developed method was based on high‐performance liquid chromatography coupled with tandem mass spectrometry using a Chiralpak IC column. The stereoselective degradation of indoxacarb enantiomers showed that the (+)‐S‐enantiomer dissipated faster than the (?)‐R‐enantiomer in all three typical tea farms. However, no enantiomerization was observed after applying pure (+)‐S‐indoxacarb. Residues on tea plant of the active ingredient (+)‐S‐indoxacarb from suspension concentrate (SC) was more persistent than that from emulsifiable concentrate (EC). Chirality 27:262–267, 2015. © 2015 Wiley Periodicals, Inc.     

草莓β-半乳糖苷酶基因FaTβgal的克隆与表达分析

利用SSH和RACE技术,从‘丰香’草莓果实中分离了1个草莓β-半乳糖苷酶(β-Gal)基因,命名为FaTβgal。FaTβgal基因cDNA序列全长2 891bp,ORF区2 448bp,编码815个氨基酸,含有保守序列GGPIILSQIENEY和凝集素结构域。FaTβgal推导氨基酸序列与已报道的3个草莓β-Gal基因Faβgal1(CAC44500)、Faβgal2(CAC44501)、Faβgal3(CAC44502)氨基酸序列有47.1%~48.1%的相似性。与其它物种24个β-Gal基因聚类分析表明,FaTβgal聚在一个独立的分枝上。采用实时荧光定量PCR技术,对FaTβgal基因在果实发育成熟过程中的表达分析表明,该基因在果实中特异表达,随着果实成熟表达量升高,粉红期达到峰值,全红期迅速下降;2个软硬不同的品种表达模式趋于一致。研究认为,FaTβgal基因是β-Gal基因家族的一个新基因,该基因可能在果实成熟软化过程中发挥作用。     

根际低氧胁迫对网纹甜瓜幼苗植株碳水化合物含量的影响

以耐低氧性明显不同的2个网纹甜瓜品种为试材,研究了低氧胁迫下植株体内碳水化合物含量的变化特征,探讨植株体内碳水化合物含量与低氧耐性之间的关系。结果表明,低氧胁迫下网纹甜瓜根系淀粉含量下降,而茎部和叶片中有淀粉积累的现象,且在耐低氧性强的‘东方星光’叶片中淀粉积累更明显;低氧胁迫下网纹甜瓜体内可溶性糖、蔗糖、果糖含量增加,且在茎部和叶片中增加幅度较大,并以耐低氧性强的‘东方星光’中增加更明显;低氧胁迫下网纹甜瓜根系葡萄糖含量降低且低于通气对照,茎部和叶片中葡萄糖含量先增加后降低,在处理8d后低于通气对照。研究发现,网纹甜瓜体内碳水化合物含量与植株的耐低氧性密切相关;耐低氧性强的品种体内可溶性糖、蔗糖、果糖含量在低氧胁迫下比耐低氧性弱的品种更高,增幅更大;体内较高的可溶性糖、蔗糖和果糖含量是植株对低氧胁迫的一种适应性反应。