Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.10.3.1 (
tyrosinase
)
9,065
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The protective effects of tea polysaccharides (TPS) and polyphenols (
TPP
) on skin were investigated. TPS1 (92% TPS), crude TPS2 (20% TPS), and
TPP
(98%) were tested. The abilities of TPS and
TPP
to protect the skin were assessed in four aspects: moisture absorption and retention, sunscreen, promoting the proliferation of fibroblast cells, and
tyrosinase
inhibitory effect. TPS and
TPP
absorbed and reserved moisture perfectly. TPS with higher purity had better moisture absorption and retention abilities. TPS1 hardly protected the skin from the sun's ultraviolet (UV) rays and had little promoting effect on fibroblasts proliferation.
TPP
, however, protected skin against UV rays and enhanced proliferation of fibroblast cells significantly.
TPP
had good
tyrosinase
inhibitory effects; TPS showed weaker
tyrosinase
inhibitory effects with the purity increased. The results indicated that
TPP
and TPS had complementary advantages and they should be appropriately combined to achieve higher performance when applied as active components of cosmetics.
...
PMID:Protective effects of tea polysaccharides and polyphenols on skin. 1967 Aug 68
The activity for photodynamic therapy of water-soluble cationic porphyrins, tetraphenylporphyrin P(V) complexes, was investigated. Bis(cyclohexylmethoxy)P(V)tetraphenylporphyrin (DCHMP(V)
TPP
), dichloroP(V)tetraphenylporphyrin (Cl
2
P(V)
TPP
), and dimethoxyP(V)tetraphenylporphyrin (DMP(V)
TPP
) could cause the photosensitized deactivation of
tyrosinase
. The tryptophan residue of human serum albumin (HSA) and several kinds of amino acids could be damaged by these P(V)porphyrins under visible light irradiation. The photosensitized damage of these biomolecules was inhibited by sodium azide, a singlet oxygen (
1
O
2
) quencher, and enhanced in deuterium oxide, suggesting the contribution of
1
O
2
. However, an excess amount of sodium azide did not completely inhibit the photosensitized damage. In addition, the redox potential measurements demonstrated the possibility of electron transfer from tryptophan and tyrosine to photoexcited P(V)porphyrins. These results suggest that electron transfer-mediated oxidation of amino acids contributes to the photosensitized protein and amino acid damage by these P(V)porphyrins. Specifically, Cl
2
P(V)
TPP
showed the highest photodamaging activity in the P(V)porphyrins used in this study. Oxidized products of amino acids by photoexcited P(V)porphyrins were analyzed with a liquid chromatography-mass spectrometer. Because of the hypoxic condition of a tumor, photodynamic therapy through a
1
O
2
-mediated mechanism should be restricted, and the electron transfer-mediated mechanism may improve the photodynamic effect. In the cases of these P(V)porphyrins, redox potential is the most important factor for photosensitized protein and amino acid oxidation through photoinduced electron transfer.
...
PMID:Photosensitized enzyme deactivation and protein oxidation by axial-substituted phosphorus(V) tetraphenylporphyrins. 2886 70
Bioactive collagen/chitosan complexes were prepared by an ion crosslinking method using fish skin collagen and chitosan solution as raw materials. Scanning electron microscopy observation confirmed that the collagen/chitosan complexes were of a uniform spherical shape and uniform particle size. The complexes were stable at different pH values for a certain period of time through swelling experiments. Differential scanning calorimetry (DSC) showed the collagen/ chitosan complexes were more stable than collagen. X-ray diffraction (XRD) showed that the complexes had a strong crystal structure, and Fourier transform infrared spectroscopy (FTIR) data revealed the changes in the secondary structure of the protein due to chitosan and
TPP
crosslinking. The content of malondialdehyde (MDA) in the complex treatment group was considerably lower, but the content of SOD was significantly higher than that of the collagen group or chitosan group. In addition, the collagen/chitosan complexes could considerably reduce melanin content, inhibit
tyrosinase
activity, and down-regulate tyrosinase mRNA expression. In conclusion, the collagen/chitosan complexes were potential oral protein preparation for antioxidant enhancement and inhibiting melanin synthesis.
...
PMID:Collagen/Chitosan Complexes: Preparation, Antioxidant Activity, Tyrosinase Inhibition Activity, and Melanin Synthesis. 3190 76
