ABSTRACT
italic>Shiraia bambusiccola is an important medicinal fungus in China. Hypocrellins with perylenequinone skeleton are main bioactive components of Shiraia bambusiccola, which are widely used in food, medicine, pesticide and other fields as natural photosensitizers. For example, "hypocrellin ointment" has already been used clinically. As a rare and vulnerable species, wild Shiraia bambusiccola resources are very limited. Due to the complex structure and chanllenge in chemical total synthesis of hypocrellins, it is urgent to find an effective strategy to rationally utilize its medicinal value while protecting the wild resources. In this study, a candidate gene cluster hpc was identified in Shiraia sp. cfcc 84681 based on careful bioinformatic analysis. A heterologous expression system for hpc gene cluster was successfully constructed and a mutant strain with high yield of hypocrellins was obtained, which mainly produced hypocrellin A and isohypocrellin A. The main ingredients in the mutant strain are consistent with that in the wild Shiraia bambusiccola. These results provide a new strategy to solve the shortage of wild Shiraia bambusiccola resources.
ABSTRACT
Objective: To study the effect of different levels of Cu2+, Fe3+, Cr3+, and Ca2+ on mycelia biomass and the hypocrellin yield by submerged culture of Shiraia bambusicola. Methods: The fungis were cultured under 27°C and 130 r/min for 96 h with each level of metal ions. Results: The biomass and the hypocrellin yield were the highest with Cr3+ of 0.005%; Fe3+ of 0.003% and 0.005% contents were favorable to the biomass and the hypocrellin yield, respectively; Ca 2+ content of 0.03% was suitable for the mycelia ' growth and the hypocrellin yield benefited from the concentration of 0.005%; Cu2+ content of 0.03% was added, both the biomass and the hypocrellin yield reached the best. Conclusion: The highest mycelia dry weight and the hypocrellin yield could reach 15.28 g/L and 8.12 mg/g, respectively in addition of metal ion.
ABSTRACT
Hypocrellin A has gained much attention in recent years due to its light-induced antitumor, antifungal and antiviral activities. Here we report that hypocrellin A exerts immunomodulatory effects on MHC-restricted presentation of antigen. Hypocrellin A inhibited class II-MHC restricted presentation of exogenous antigen, but not class I MHC-restricted presentation of exogenous antigen, in dendritic cells. Hypocrellin A also inhibited the cytosolic pathway of endogenous antigen presentation. However, hypocrellin A did not inhibit the expression of class I and class II MHC molecules on dendritic cells (DCs), the phagocytic activity of DCs, or the H-2K(b)-restricted presentation of a synthetic peptide, SIINFEKL. These results show that hypocrellin A differentially modulates the MHC-restricted antigen presentation pathways.
Subject(s)
Antigen Presentation , Cytosol , Dendritic Cells , Perylene , QuinonesABSTRACT
Objective To obtain anamorphosis of Shiraia bambusicola producing the component,hypocrellin A effectively.Methods A strain was isolated from the fruit of S.bambusicola by separating its hypha and was cultured by solid-state fermentation.One of the pure chemical compounds isolated from the stroma of wild S.bambusicola was studied on the basis of UV/VIS,IR,MS spectrometric analysis and physicochemical constants.Results The pigment is proved to be hypocrellin A.The isolate was determined as the stable anamorphosis strain 0258 of S.bambusicola.Conclusion A namorphosis strain of S.bambusicola is obtained and precisely appraised for the first time.This study will provide basis for the future massively industrialized hypocrellin production.
ABSTRACT
Determination of the quantum yields of Gibberellin, Hypocrellin A and phenol showed that there were respectively ranges of excitation wavelengths for the relative constant of quantum yields of them. The quantum yields of Gibberellin excited by its own multiple excitaion wavelengths (285 and 410 nm) equaled each other. The quantum yields were similar by excitation of 585 nm and 625 nm with determination of the emission at 640 nm for Hypocrellin A. The emission at 690nm with Hypocrellin A would disappear after it had stood at room temperature for about one month, it suggests that it should be convenient to determine the quantum yield, at a shorter wavelength as for the excitation maximum, of a fluorophore whose concentration was low, weak quantum yield and wavelengths of the excitation and emission locating nearly, with a strong Reilagh scattering; and that the 690 nm emission of Hypocrellin A should be emitted by the groups which were subjected to the effects of physical or chemical disturbences.
ABSTRACT
The research status is reviewed on taxonomic position, ecology, biological active matter and artificial cultivation of Shiraia bambusicola. Following problems are presented: whether there are new species and host specificity of Shiraia bambusicola. Since the artificial cultivation of stroma of Shiraia bambusicola has not been success, Shiraia bambusicola is in situation of emerge of itself and perish of itself so that it is not beneficial to resource protection and continual utilization of this medicinal fungus. It is pointed out that molecular biology of Shiraia bambusicola should be further researched and technology of artificial cultivation of Shiraia bambusicola should be explored in order to exploit and usage of Shiraia bambusicola.