蓝、紫单色光处理对三叶青生理及总黄酮含量时空变化的影响

Spatiotemporal changes in physiology and total flavonoids of Tetrastigma hemsleyanum in response to blue and purple monochromatic light

三叶青作为“新浙八味”之一的药材,具有抗肿瘤、抗病毒和退热等临床效果,其主要有效成分为黄酮类化合物。三叶青生长在林间荫蔽环境,其活性成分合成、生长发育、生理变化等均会受到林下短波光调控。为明晰短波光对三叶青品质及生理变化的调控规律,本文选择了蓝光和紫光单色光作为处理光源,以白光作为对照,分别处理7 d、15 d、30 d、45 d和60 d,测定三叶青总黄酮含量、黄酮代谢合成酶活性、生理生化指标(光合色素、抗逆酶活性和丙二醛含量、初生代谢可溶物),以期探讨三叶青黄酮代谢和生理生化变化对短波光条件的响应及规律。结果表明:持续的单色短波光处理,使三叶青处于轻度胁迫状态,蓝光处理后三叶青中总黄酮含量最高,其中叶片含量为137.75 mg·g^(-1),块根中为149.00 mg·g^(-1);紫光处理使叶片和块根中的苯丙氨酸酶活性[96.50 U·g^(-1)(FW)、109.47 U·g^(-1)(FW)]和叶片中查尔酮异构酶活性[65.17 U·g^(-1)(FW)]均达最高,蓝光处理块根中的查尔酮合成酶活性最高,为46.76 U·g^(-1)(FW)。此外,光合色素、抗逆能力和可溶性物质对短波光的响应均有差异,与白光相比,蓝光和紫光均可促进渗透调节物质的积累。本研究的结果可为光调控三叶青品质提供理论基础和实践指导。

Tetrastigma hemsleyanum Diels et Gilg has antitumor,antiviral,and fever-relieving properties.The main active components are flavonoids.It grows in shaded environments in forests,and its growth,development,physiological changes,and synthesis of active components are regulated by short-wavelength light of undergrowth.To explore the spatial and temporal responses of physiological mechanisms and flavonoid synthesis in T.hemsleyanum to short-wavelength light,blue or purple monochromatic light were selected as treatment light sources,and white light was used as the control for 7,15,30,45,and 60 d.The total flavonoids content,flavonoid-related enzymes activities,and physiological and biochemical indexes,such as photosynthetic pigments,anti-resistance enzymes activities,malondialdehyde(MDA),and primary metabolic solubility,of leaves were measured to investigate the spatial and temporal responses of the flavonoid synthesis process and physiological and biochemical changes in T.hemsleyanum to shortwavelength light conditions.The results showed that:1)short-wavelength light treatments regulated the changes in photosynthetic pigments contents;the control and blue light treatments increased photosynthetic pigments contents,but the purple light treatment significantly inhibited this effect.2)Continuous monochromatic short-wave light treatments put T.hemsleyanum under mild stress,and the total flavonoids content was the highest with blue light treatment(137.75 mg·g^(-1)in leaves and 149.00 mg·g^(-1)in tubers).The phenylalnine ammonialyase activities in leaves and tubers(96.50 U·g^(-1)FW,109.47 U·g^(-1)FW)and chalcone isomerase activity in leaves(65.17 U·g^(-1)FW)were highest under purple light treatment;while chalcone synthase activity in tubers was the highest with blue light treatment(46.76 U·g^(-1)FW).In addition,photosynthetic pigments,resilience,and soluble substances differed in their responsiveness to short-wave light,and both blue and purple light promoted the accumulation of osmoregulatory substances compared with white light.This study provided a theoretical basis and practical guidance for light regulation of T.hemsleyanum quality.