摘要
【目的】海藻(海带)降解物对作物具有抗逆促生作用,研究海带菌解和酶解的最佳工艺条件,并比较两个工艺生产的降解产物对菜心的抗逆效果。【方法】采用单因素和正交试验,探究不同的底物浓度、接种量、溶液pH、降解温度分别对微泡菌Microbulbifer sp.SH-1和海藻酸裂解酶AlgSH7制备海藻降解产物的影响。同时,借助光学显微镜,研究SH-1菌和AlgSH7酶降解过程中海带细胞形态变化。并在此基础上,利用盆栽试验,研究海带菌解产物、酶解产物对菜心非生物胁迫抗性的影响。【结果】海藻酸裂解酶AlgSH7降解海带的最佳工艺条件是底物浓度2%,酶添加量6%,降解体系初始pH 8.5,温度44℃;SH-1菌株降解海带的最佳工艺条件是底物浓度2.5%,接种量1.5%,降解体系初始pH 7.5,温度32℃。与菌解产物相比,酶解产物中海藻酸、总糖、还原糖含量分别提高141.8%、57.6%、150.5%,而褐藻多酚、甘露醇、甜菜碱含量分别下降35.3%、60.6%、62.6%,但菌解工艺的产率比酶解工艺高9.3%。细胞形态观察结果表明,海带原始细胞排列紧密,形状规则饱满,随菌解或酶解时间的延长,海带细胞可视面积变小,细胞之间的间距增大。降解24 h时,酶解海带细胞可视面积仅为菌解的77.2%。在盆栽试验中,中度干旱条件下(土壤相对含水量50%),酶解液灌根处理的菜心生物量比菌解液处理提高13.7%;酶解液配施水溶肥(NPK,N:P_(2)O_(5):K_(2)O=110:50:60)处理的菜心生物量比菌解液配施NPK处理明显提高10.6%。淹水条件下(淹水层深度2 cm),酶解液处理的菜心生物量比菌解液处理降低7.1%,但均显著高于对照处理;酶解液配施NPK处理的菜心生物量比菌解液配施NPK处理提高5.6%。盐胁迫条件下(土壤中NaCl含量24 g/kg),海带酶解液处理的菜心生物量比菌解液处理有增加趋势,但增加不显著。【结论】海带酶解产物中海藻酸、总糖、还原糖含量高于菌解�
【Objectives】Seaweed is one of the marine resources;its hydrolyzed product has growth-promoting and stress resistance effects.Here we optimized the parameters of two routine seaweed processing and compared their products.【Methods】Single factor and orthogonal experiments were used for the optimization of procession parameters for bacterial and enzymatic hydrolysis of brown algae(Laminaria japonica).In bacteria degradation and enzymatic hydrolysis process,the substrate concentration,algae dosage,pH value and temperature for the degradation were optimized,the used bacteria were Microbulbifer sp.SH-1 and alginate lyase AlgSH7.Meanwhile,the morphology of seaweed cells was observed before and after both kind of hydrolyzation under optical microscope.The effects of the two kinds of products were tested with a pot experiment,using Chinese cauliflower cabbage as test material.【Results】The optimal conditions for alginate lyase AlgSH7 were 2%substrate concentration,6%enzyme dosage,pH 8.5 and degradation temperature of 44℃.For strain SH-1,the optimal conditions were 2.5%substrate concentration,1.5%bacterial solution,pH 7.5 and degradation temperature of 32℃.Compared with bacteria degraded product(BDP),the enzyme hydrolyzed products(EHP)increased alginate and total sugar contents and reduced sugar by 141.8%,57.6%,and 150.5%,respectively.The contents of polyphenol,mannitol,and betaine decreased by 35.3%,60.6%,62.6%,respectively.The yield of BDP was 9.3%higher than that of the EHP.Before hydrolyzation,the kelp primitive cells were tightly arranged,and their traits were regular and full.With prolonged bacterial or enzymatic hydrolysis,the visible area of kelp cells became smaller,and the distance between cells increased.After being degraded by enzymatic hydrolysis for 24 h,the visible area of seaweed cells was only 77.2%of that by bacterial hydrolysis.Pot experiments showed that under moderate drought conditions(relative soil water content 50%),the crop biomass treated with EHP was 13.7%higher than that treated wi
作者
杨春妹
杨锦
崔丹丹
李立斌
沈宏
YANG Chun-mei;YANG Jin;CUI Dan-dan;LI Li-bin;SHEN Hong(College of Resources and Environment,South China Agricultural University,Guangzhou,Guangdong 510642,China;Lihe Vegetable Planting Professional Cooperative,Shantou,Guangdong 515833,China)
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2021年第8期1432-1444,共13页
Journal of Plant Nutrition and Fertilizers
基金
国家重点研发计划(2016YFD0200405-5)
广东省科技计划项目(2019B030301007)。
