ABSTRACT
Ultrasonic degradation has become a promising strategy for producing modified pectin (MP). In this study, the impact of ultrasonic treatment at various pH values (4.0, 7.0, and 10.0) on the macromolecular, structural and rheological characteristics of citrus pectin was investigated. Results demonstrated that ultrasonic irradiation at the higher pH led to larger reductions in the intrinsic viscosity and weight-average molecular weight of pectin. The degradation kinetics of pectin at different pH values under ultrasound well fitted to a second-order reaction kinetics model. Acoustic cavitation, ß-elimination, and demethylation led to the breakage of glycosidic linkages of side chains and methoxyl groups of pectin, but did not have noticeable influences on the main chain of pectin. The ultrasonic treatment at a high pH led to an apparent change in the rheological characteristics of pectin. Therefore, ultrasonic treatment at various pH values can be developed as a viable means to prepare desirable MP.
Subject(s)
Pectins/chemistry , Rheology , Ultrasonic Waves , Hydrogen-Ion Concentration , Kinetics , Molecular Weight , ViscosityABSTRACT
The objective of this study was to explore the effect of magnesium acetate (MA) addition on the endo-polyphenol yield by Phellinus baumii and establish a feasible additive strategy. The optimal three-point MA addition strategy (0.05 g/L concentration of MA added at 0 h and 6 h, 0.9 g/L concentration of MA added at 12 h) was employed to obtain maximum endo-polyphenol yield. The maximum endo-polyphenol production was reached at 1.22 g/L, which was 1.39-fold higher than that of the control. Additionally, the endo-polyphenol showed stronger antioxidant activity in vitro compared with the control, including DPPH· scavenging capacity (78.76%) and Trolox equivalent antioxidant capacity (TEAC) (32.28 µmol Trolox/g sample). HPLC analysis showed that the endo-polyphenol production of the crude ethanol extracts was significantly higher than that of the control. Hispidin was isolated and identified from the ethanol extract of the culture mycelia from Ph. baumii with the three-point MA addition strategy. Hispidin showed a strong ability to scavenge DPPH free radicals and TEAC, equivalent to positive (vitamin C) value of 89.41% and 75.98%, respectively. Furthermore, hispidin protected H2O2-induced PC12 cells injured by decreased oxidative stress level. These results indicated that the MA multi-stage addition strategy was dependable, and could be used to develop new natural antioxidants for foods or medicines.
Subject(s)
Acetates/adverse effects , Antioxidants/pharmacology , Basidiomycota/chemistry , Complex Mixtures/pharmacology , Magnesium Compounds/adverse effects , Polyphenols/pharmacology , Pyrones/pharmacology , Agaricales , Animals , Antioxidants/chemistry , Antioxidants/isolation & purification , Chromans/adverse effects , Chromatography, High Pressure Liquid , Complex Mixtures/chemistry , Complex Mixtures/isolation & purification , Free Radicals/adverse effects , Hydrogen Peroxide/adverse effects , Mycelium/chemistry , Oxidative Stress/drug effects , PC12 Cells , Polyphenols/chemistry , Polyphenols/isolation & purification , Pyrones/chemistry , Pyrones/isolation & purification , RatsABSTRACT
Various diseases such as cancer, hyperglycemia, and obesity negatively influence people's health and daily life. Mushroom species are miniature pharmaceutical factories producing hundreds of novel constituents with a long history of use in Oriental medicine. As a new therapy, they have attracted much attention owing to their potent therapeutic activity. Phellinus sensu lato (s.l.) is a well-known medicinal mushroom genus that has long been used in preventing ailments, including gastroenteric dysfunction, diarrhea, hemorrhage, and cancers, in Oriental countries, particularly in China, Japan, and Korea. Isolated compounds or complex extracts from Phellinus demonstrate specific bioactivity. Low-molecular-weight components, especially terpenoids, polyphenols, and other secondary metabolites, still exhibit biological activity. This review highlights the bioactive compounds from Phellinus s. l. mushrooms as being potent and having unlimited applications, especially the bioactive low-molecular-weight compounds, such as terpenoids, polyphenols, and their derivatives; also, pharmacological properties of the extracts and fractions from the fruiting bodies and the mycelia of Phellinus s. l., and the mechanism of the pharmacological activity have been discussed. This review summarized the two parts as mentioned above over a period of 7 years from 2011 to 2017.
Subject(s)
Agaricales/chemistry , Fruiting Bodies, Fungal/chemistry , Mycelium/chemistry , China , Japan , Medicine, East Asian Traditional , Molecular Weight , Polyphenols/analysis , Republic of Korea , Secondary Metabolism , Terpenes/analysisABSTRACT
To obtain Phellinus baumii strain with high flavonoids yield, ARTP was employed to generate mutants of a Ph. baumii strain, which were screened for higher flavonoids content. After five rounds of screening, four mutants were identified to produce more flavonoids than the wild type strain under optimal conditions, of which A67 was the mutant with the highest flavonoids productive capacity. When cultured in shake flasks, the maximum intracellular total flavonoids production of A67 reached 0.56 g/L, 86.67% higher than the total flavonoids in CK. Antagonistic testing, RAPD, and HPLC analysis suggested that ARTP caused changes of the genetic material and metabolites in Ph. baumii. In addition, the superiority of A67 to CK was proved by liquid fermentation using unstructured kinetic models, which was performed in a 50-L fermentor. The maximum intracellular total flavonoids production and dry mycelium weight of A67 reached 0.64 g/L and 15.24 g/L, which was an increase of 88.24% and 18.23% compared with CK, respectively. This work could provide an efficient and practical strategy to obtain high flavonoids production strains and the superiority of A67 could also provide a reference to further increase flavonoids production of Ph. baumii in large-scale production mode by submerged fermentation process.
Subject(s)
Basidiomycota/isolation & purification , Basidiomycota/metabolism , Fermentation , Flavonoids/biosynthesis , Metabolic Engineering/methods , Mutagenesis , Plasma Gases , Basidiomycota/genetics , Basidiomycota/growth & development , Chromatography, High Pressure Liquid , Culture Media/chemistry , Genetic Testing , Metabolomics , Random Amplified Polymorphic DNA TechniqueABSTRACT
By-1 was obtained from spent broth from submerged cultures of Taiwanofungus camphoratus. This report evaluates the effects of By-1 on plate clone formation, wound healing, cell cycle, activated caspase-3 expression, and ROS release in A549 lung cancer cells. The result of plate clone formation assay revealed that By-1 could dramatically inhibit the viability of A549 cells in vitro. The inhibitory effect of By-1 on cell migration was tested using a wound healing assay. Proliferation rates of A549 cells were significantly inhibited following exposure to By-1 (12.5, 50, and 80 µg/mL). Flow cytometry revealed that the extracts increased, in a concentration-dependent manner, the number of cells in the G0/G1 phases of the cell cycle. The results of the caspase-3 experiment suggested that By-1 could induce A549 cells apoptosis, and this apoptosis was related to the release of reactive oxygen species by the A549 cells. All these results indicate that By-1 has potential in anti-lung cancer drug development.