The Effect of Magnesium on Accumulations of Primary Metabolites and Yield of Blumea balsamifera

[Objectives]This study was conducted to investigate the effects of magnesium on the yield of Blumea balsamifera(L.)DC.and the accumulation of primary metabolites that affect yield of the medicinal material.[Methods]The annual seedlings of B.balsamifera were selected as experimental materials.The treatment concentrations of magnesium(Mg)were set as 0,1.5,15 and 150 mg/ml supplied by MgSO4·7H2O.The yield of the medicinal material was measured dynamically.And the content of total sugar was determined by 3,5-dinitrosalicylic acid colorimetry;the content of crude protein was determined by the Kjeldahl method;the ash content was determined by the high-temperature burning method;the crude fat content was determined with a crude fat instrument;and the crude fiber content was determined by the acid-base washing and weighing method.[Results]Mg significantly increased the yield of B.balsamifera medicinal material,especially 15 mg/ml Mg.It was found that in September,October and November,1.5 mg/ml and 15 mg/ml Mg significantly increased the contents of primary metabolites including total sugar,ash,crude protein,crude fat and crude fiber,and 150 mg/ml of Mg increased the accumulation of total sugar,ash,crude protein and crude fiber to different degrees,but had certain inhibitory effect on the accumulation of crude fat.In December,the application of Mg inhibited the accumulation of total sugar,ash and crude protein to different degrees,but significantly promoted the accumulation of crude fat and fiber.[Conclusions]This study provides a theoretical basis for clarifying the effects of different concentrations of magnesium on plant growth.

Those Responsible for the Pharmacological Actions of Plants are the Active Secondary Metabolites

Objectives: To relate the presence of the active secondary metabolites in the pharmacological actions and the therapeuticeffects of the plants. Methods: Search about the topic in the last 5 years and present some active secondary metabolites that explainthe pharmacological actions and therapeutic effects of medicinal plants. Conclusions: It was based on the search of articles in theVirtual Library in Health (Spanish: BVS) and using the key words: secondary metabolites, phytotherapy, medicinal plants.

Brassinosteroids fine-tune secondary and primary sulfur metabolism through BZR1-mediated transcriptional regulation

For adaptation to ever-changing environments,plants have evolved elaborate metabolic systems coupled to a regulatory network for optimal growth and defense. Regulation of plant secondary metabolic pathways such as glucosinolates(GSLs) by defense phytohormones in response to different stresses and nutrient deficiency has been intensively investigated, while how growth-promoting hormone balances plant secondary and primary metabolism has been largely unexplored. Here, we found that growth-promoting hormone brassinosteroid(BR) inhibits GSLs accumulation while enhancing biosynthesis of primary sulfur metabolites, including cysteine(Cys) and glutathione(GSH) both in Arabidopsis and Brassica crops, fine-tuning secondary and primary sulfur metabolism to promote plant growth. Furthermore, we demonstrate that of BRASSINAZOLE RESISTANT 1(BZR1), the central component of BR signaling, exerts distinct transcriptional inhibition regulation on indolic and aliphatic GSL via direct MYB51 dependent repression of indolic GSL biosynthesis, while exerting partial MYB29 dependent repression of aliphatic GSL biosynthesis. Additionally, BZR1 directly activates the transcription of APR1 and APR2 which encodes rate-limiting enzyme adenosine 5′-phosphosulfate reductases in the primary sulfur metabolic pathway.In summary, our findings indicate that BR inhibits the biosynthesis of GSLs to prioritize sulfur usage for primary metabolites under normal growth conditions.These findings expand our understanding of BR promoting plant growth from a metabolism perspective.

Can soil microbial diversity influence plant metabolites and life history traits of a rhizophagous insect？ A demonstration in oilseed rape

Interactions between plants and phytophagous insects play an important part in shaping the biochemical composition of plants. Reciprocally plant metabolites can influ- ence major life history traits in these insects and largely contribute to their fitness. Plant rhizospheric microorganisms are an important biotic factor modulating plant metabolites and adaptation to stress. While plant-insects or plant-microorganisms interactions and their consequences on the plant metabolite signature are well-documented, the impact of soil microbial communities on plant defenses against phytophagous insects remains poorly known. In this study, we used oilseed rape （Brassica napus） and the cabbage root fly （Delia radicum） as biological models to tackle this question. Even though D. radicum is a belowground herbivore as a larva, its adult life history traits depend on aboveground signals. We therefore tested whether soil microbial diversity influenced emergence rate and fitness but also fly oviposition behavior, and tried to link possible effects to modifications in leaf and root metabolites. Through a removal-recolonization experiment, 3 soil microbial modalities （＂high,＂ ＂medium,＂ ＂low＂） were established and assessed through amplicon sequencing of 16S and 18S ribosomal RNA genes. The ＂medium＂ modality in the rhizosphere significantly improved insect development traits. Plant-microorganism interactions were marginally associated to modulations of root metabolites profiles, which could partly explain these results. We highlighted the potential role of plant-microbial interaction in plant defenses against Delia radicum. Rhizospheric microbial communities must be taken into account when analyzing plant defenses against herbivores, being either below or aboveground.

The utility of metabolomics as a tool to inform maize biology

With the rise of high-throughput omics tools and the importance of maize and its products as food and bioethanol,maize metabolism has been extensively explored.Modern maize is still rich in genetic and phenotypic variation,yielding a wide range of structurally and functionally diversemetabolites.The maize metabolome is also incredibly dynamic in terms of topology and subcellular compartmentalization.In this review,we examine a broad range of studies that cover recent developments in maize metabolism.Particular attention is given to current methodologies and to the use of metabolomics as a tool to define biosynthetic pathways and address biological questions.We also touch upon the use of metabolomics to understand maize natural variation and evolution,with a special focus on research that has used metabolite-based genome-wide association studies(mGWASs).