Publications by authors named "Guan-Hua Cao"

Article Synopsis
  • The study investigates how arbuscular mycorrhizal fungi (AMF) influence the composition of bioactive saponins in a valuable medicinal herb from China, using advanced mass spectrometry techniques.
  • Researchers identified a total of 202 terpenoid metabolites, with 150 being triterpene glycosides, and found significant differences between samples treated with AMF and control samples.
  • The treatment with AMF led to an increase in specific notoginsenosides and suggested that the pathways for synthesizing rare notoginsenosides are activated by AMF, potentially enhancing the ecological farming of medicinal herbs.
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is a highly valued perennial medicinal herb plant in Yunnan Province, China, and the taproots are the main medicinal parts that are rich in active substances of saponins. The main purpose of this study is to uncover the physiological and molecular mechanism of saponin accumulation triggered by methyl jasmonate (MeJA) under arbuscular mycorrhizal fungi (AMF) by determining physiological indices, high-throughput sequencing and correlation analysis. Physiological results showed that the biomass and saponin contents of , the concentrations of jasmonic acids (JAs) and the key enzyme activities involved in notoginsenoside biosynthesis significantly increased under AMF or MeJA, but the interactive treatment of AMF and MeJA weakened the effect of AMF, suggesting that a high concentration of endogenous JA have inhibitory effect.

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This study aims to evaluate the tolerance of endophytic fungi isolated from the fibrous roots of Polygonatum kingianum to arsenic (As) and cadmium (Cd) and their physiological response mechanisms. Five isolated strains were obtained with EC values for As(V) ranging from 421 to 1281 mg/L, while the other three strains tolerated Cd(II) with an EC range of 407-1112 mg/L. Morphological and molecular identification indicated that these eight strains were Cladosporium spp.

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The main purpose of this study was to reveal the nutritional value and antioxidant activity of 34 edible flowers that grew in Yunnan Province, China, through a comprehensive assessment of their nutritional composition and antioxidant indices. The results showed that sample A3 of Asteraceae flowers had the highest total flavonoid content, with a value of 8.53%, and the maximum contents of vitamin C and reducing sugars were from Rosaceae sample R1 and Gentianaceae sample G3, with values of 143.

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The crisis of arsenic (As) accumulation in rhizomes threatens the quality and safety of Panax notoginseng (Burk.) F.H.

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Background: Panax notoginseng is a medicinally important Chinese herb with a long history of cultivation and clinical application. The planting area is mainly distributed in Wenshan Prefecture, where the quality and safety of P. notoginseng have been threatened by high concentration of arsenic (As) from the soil.

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is one of the dominant dark septate endophytes (DSEs) colonizing metal-polluted slag heaps in southwest China. It shows numerous super-metal-tolerant characteristics, but the molecular mechanisms involved remain largely unknown. In the present study, the functional roles of a specific set of ATP-binding cassette (ABC) transporters in were characterized.

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Various metal transporters mediate sub-cellular sequestration of diverse metal ions, contribute to cellular metal tolerance, and control metal partitioning, particularly under conditions of high rates of metal influx into organisms. In the current study, a ubiquitous and evolutionary conserved metal transporter gene, homology to natural resistance associated macrophage protein (Nramp), was cloned from a metal-tolerant isolate of dark septate endophyte (DSE, Exophiala pisciphila), and its functional and transcript characterization were analyzed. The full-length Nramp gene from E.

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Glutathione S-transferases (GSTs) compose a family of multifunctional enzymes that play important roles in the detoxification of xenobiotics and the oxidative stress response. In the present study, twenty four GST genes from the transcriptome of a metal-tolerant dark septate endophyte (DSE), Exophiala pisciphila, were identified based on sequence homology, and their responses to various heavy metal exposures were also analyzed. Phylogenetic analysis showed that the 24 GST genes from E.

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