1.Studies on the antioxidation activity of squid(Dosidicus eschrichitii Steenstrup) skin gelatin hydrolysate
Chinese Journal of Marine Drugs 1994;0(04):-
Objective To investigate the free radical scavenging effects and antioxidation activity of squid(Dosidicus eschrichitii Steenstrup) skin gelatin hydrolysate.Methods The free radical scavenging effects of the hydrolysate on superoxide and hydroxyl free radicals were assessed by chemiluminescence analysis method.The activity of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px) and content of malondialdehyde(MDA),hydroxyprolyne(Hyp) in blood serum and skin tissue in galactose treated mice were analyzed after 42 days of hydrolysate feeding.Results and Conclusion The fraction with relative molecule weight less than 2000 D of the hydrolysate had the highest free radical scavenging effects on superoxide and hydroxyl free radicals,and the activities of SOD,GSH-Px were enhanced,the quantity of MDA in blood serum and skin tissue of the mice was decreased and the quantity of Hyp in skin tissue of mice was increased after the hydrolysate administration.
2.Research on anti-fatigue effect of syngnathus acus L.
Chinese Journal of Marine Drugs 1994;0(04):-
The study analyzed the compositions of Syngnathus acus L and discussed its anti-fatigue effect. Prepared lipid and enzymatic hydrolysate. The animal experiment methods are such as followed-(1)Enduring capacity experiment. (2)Determining LA (Lactic Acid) concentrations before and after swimming sports. (3)Determining the content of muscle glyco-gen and hepatic glycogen of mice. These experiments showed that lipid and enzymatic hydrolysate are both able to prolong swimming time of mice (P
3.Progress in studies of marine bioactive peptides and their bioactivities
Mingyong ZENG ; Haiying CUI ; Bafang LI
Chinese Journal of Marine Drugs 1994;0(01):-
Bioactive peptides in the marine organisms such as sponges,ascidian,fishes,shellfish,etc. and their bioactivities of antineoplastic, antimicrobial, antihypertension and antioxidation were reviewed in this paper.
4.Separation and partial characterization of agiotensin Ⅰ-converting enzyme inhibitory peptides from enzymic hydrolysates of red tilapia skin collagen
Mingyong ZENG ; Shengjun CHEN ; Laihao LI ; Bafang LI
Chinese Journal of Tissue Engineering Research 2007;11(2):397-400
BACKGROUND: Agiotensin Ⅰ -converting enzyme (ACE) inhibitory peptides which are separated from red tilapia skin collagen should be researched further.OBJECTIVE: To obtain a peptide of high ACE inhibitory activity through enzymic hydrolysates of red tilapia skin collagen.DESIGN: Enzymic hydrolysates were done with orthogonal experimental method; decompression peptide was separated with ultrafiltration, gel chromatography and hypertensive liquid chromatography.SETTING: Laboratory of Aquatic Products, Chinese Marine University.MATERIALS: The red tilapia weighing (500+50)g was donated by Branch Factory of Jimo Redian Factory. ACE was isolated from hog lung.METHODS: The experiment was carried out in the Laboratory of Aquatic Products, Chinese Marine University from May Bergman.①The collagen from red tilapia skin was extracted using the method described by Grossman and Bergman.The collagen extraction was hydrolyzed with compound enzymes in the order of bromelain and Alcalase 2.4 L.The red tilapia collagen hydrolysates (RTCH) were subsequently boiled to inactivate the enzyme. The resultant RTCH was fractionated through three different UF membrane bioreactor system having a range of molecular weight cut-offs (MWCO) of Mr 6 000, 4 000 and 1 000. Three portions were obtained: RTCH-I (M, 6000-4000), RTCH- Ⅱ (Mr 4000-1000)and RTCH-Ⅲ(Mr<1000).②The ACE inhibitory 50%of ACE activity was defined as the IC50 value.③RTCH-Ⅲ(1.5 Ml) with the highest activity among RTCHs was loaded onto a Sephadex G-25 column (1.6×100 cm), and the absorbance of theeluent was monitored at 220 nm. Four samples of primary hydrolysates, RTCH- Ⅰ, RTCH- Ⅱ and RTCHⅢ were separated to collect active fractions which were pooled and lyophilized, immediately. The lyophilized fraction was separated with HPLC ODS-C18 analysis column to obtain component of high activity. Meanwhile, the same method was used to measure ACE inhibitory rate.④Each sample was hydrolyzed with 6 mol/L hydrochloric acid containing 1g/L thioglycolic acid at 110 ℃ for 24 hours in vacuum. The amino acid compositions of the resultant hydrolysates were determined on an amino acid auto analyzer, and molecular weight was measured with HPLC technique.MAIN OUTCOME MEASURES:①ACE inhibitory activity of fractionated RTCHS;②Purification of ACE inhibitory peptide;③Amino acid analysis of ACE inhibitory peptides.RESULTS:①ACE inhibitory activityof fractionated RTCHs:IC50values of RTCH-Ⅰ,RTCH-Ⅱand RTCH-Ⅲ were 3.30,2.23 and 0.31 g/L,and inhibitory of RTCH-Ⅲ was the highest.②Purification of ACE inhibitory peptide: The IC50 value of the four peak were 3.5, 2.12, 1.56 and 0.65 g/L, respectively. Results in Figures 2, 3, 4 and 5 showed that the high active fractions were: 6K4, 4K2, 1K2 and ACF2, and the inhibitory ratio were 11.1%, 89.9%, 65.0% and 49.7%, respectively.Among of these fractions,the 4K2 exhibited the highest inhibitory rate.③Amino acid analysis of ACE inhibitory peptides: Separated peptide products had more aromatic and hydrophobic amino acids.CONCLUSTON: Enzymic hydrolysates of red tilapia skin collagen have high ACE inhibitory peptide which is separated with ultrafiltration, gel chromatography and hypertensive liquid chromatography.
5.Effects of collagen polypeptides from squid(Dosidicus gigas)skin on melanogenesis in B16 melanoma cells
Jingfeng WANG ; Yi WANG ; Fengxia CUI ; Bafang LI ; Changhu XUE
Chinese Pharmacological Bulletin 2003;0(09):-
10000 u,SP2:6 000 u0.05),the melanogenesis and tyrosinase activity were inhibited remarkably(P
6.Improvement and application of an analysis method for food-derived ACE inhibitory peptides
Yuanhui ZHAO ; Bafang LI ; Yijie LIU ; Juan GENG ; Mingyong ZENG
Chinese Journal of Marine Drugs 1994;0(04):-
Objective To establish a rapid and accurate analysis method for food-derived ACE inhibitory peptides activity in vitro.Methods Reaction time of ACE and substrate was by measuring the hippuric acid liberated in the ACE reaction mixture at regular intervals;An optimal RP-HPLC method to measure food-derived ACE inhibitory peptides activity in vitro was set up.The hippuric acid from ACE reaction mixture(sea cucumber peptides were regarded as ACE inhibitor) was estimated by Zorbax SB-C_(18) analytical column with acetonitrile and ultrapure water as mobile phase.Results The reaction time of ACE with substrate was determined at sixty minutes;The elution was carried out with the ratio of acetonitrile to ultrapure water was 1:1(0.1%TFA) at a flow rate of 0.4 mL?min~(-1).The ahsorbance of the eluent was monitored at 228 nm,and column temperature was 25℃.The relationship between hippuric acid concentration and peak area exhibited a good linearity in the concentration ranges of 0~200?g?mL~(-1) and 200~800?g?mL~(-1).The RP-HPLC method was further validated by captopril,the oyster hydrolysate and the anchovy hydrolysate.Conclusion The method has been proved to be convenient,accurate and suitable for the analysis of foodderived ACE inhibitory peptides activity in vitro.
7.Chemical constituents contained in Salvia castanea.
Guiwu QU ; Xidian YUE ; Fengshan AN ; Shengjun DAI ; Guisheng LI ; Bafang LI
China Journal of Chinese Materia Medica 2012;37(13):1985-1989
OBJECTIVETo investigate chemical constituents contained in Salvia castanea.
METHODThe compounds were separated and purified by silica gel, macroporous resin, RP-C18 and Sephadex LH-20 column chromatography. The structures were identified on the basis of physicochemical property and spectral data.
RESULTNineteen compounds were separated and identified as tanshinone II(A) (1) , tanshinone II(B) (2), hydroxytanshinone II(A) (3), tanshinone I(4), dihydrotanshinone I(5), cryptotanshinone (6) , neotanshinone A(7) , neotanshinone B(8) , tanshinoldehyde(9), przewaquinone A(10), przewaquinone B(11), sugiol(12), caffeic acid(13), rosmarinci acid(14), ethylrosmarinate(15), lithospermic acid(16), pro-lithospermic acid ( 17) , protocatechualdehyde (18), and danshensu(19).
CONCLUSIONCompounds 2, 3, 7-13 and 15-19 were separated from S. castanea for the first time.
Chromatography ; methods ; Drugs, Chinese Herbal ; chemistry ; Medicine, Chinese Traditional ; Salvia ; chemistry
8.Preparation and evaluation of fish skin acellular dermal matrix for oral guided tissue regeneration
Yuanyuan WANG ; Wenshan SONG ; Dejun YU ; Yuankun DAI ; Bafang LI
Chinese Journal of Tissue Engineering Research 2019;23(10):1526-1532
BACKGROUND: Current oral restoration membranes are expensive with a potential risk of zoonotic virus, so new membranes are in need. OBJECTIVE: To prepare fish skin acellular dermal matrix and evaluate its efficiency of decellularization, biomechanical properties and biocompatibility, in order to explore its feasibility as an oral restoration membrane. METHODS: The skin of Astroconger Myriaster was harvested to prepare acellular dermal matrix by decellularization via a combination of physical method and chemical and biological reagents. The micromorphology of the material was observed under scanning electron microscope. Tissue composition was analyzed by hematoxylin-eosin, Masson and PAS staining. The DNA content was detected using a kit. The biocompatibility was evaluated through cytotoxicity and animal skin stimulation tests. RESULTS AND CONCLUSION: The prepared acellular dermal matrix: (1) was white or light yellow, with strength and toughness; (2) exhibited a double-layered structure composed of a dense layer and a loose layer; (3) was mostly composed of collagen without PAS positive substance, showing good decellularization; (4) had a significantly lower DNA content than natural fish skin and commercial oral restoration membrane; and (5) possessed good biocompatibility, with very low cytotoxicity and no stimulation to the animal skin. Therefore, the prepared acellular dermal matrix of fish skin shows a potential in the preparation of oral guided tissue regeneration membrane.