1, Xie chaotian, researcher of Porphyra haitanensis, Jimei university, Xiamen, Fujian:
All the lavers sold in the market are dried and roasted. After baking, the cell membrane of laver was destroyed. Porphyra grows in seawater. When soaked in fresh water, phycoerythrin and phycocyanin in laver dissolve and appear very purple color, which is not caused by dyeing.
2. Identification of Porphyra yezoensis
Fresh laver is dark green and shiny. High-quality laver has purple-black luster (some are purple-red or purple-brown), thin slice and soft taste; Inferior laver has poor surface gloss, uneven thickness, green in red, poor taste and fragrance, and many weeds and inclusions.
If laver smells fishy and musty, it means that laver is not fresh. At the same time, high-quality laver can hardly see impurities after soaking, and its leaves are relatively neat; Inferior laver not only has many impurities, but also has irregular leaves. If it turns green after soaking, it means that the quality is very poor, and even other algae are artificially colored and counterfeit.
In addition, after the laver is bought back, it can be roasted on the fire. High-quality laver should be green after baking, and if it is yellow, it is inferior laver. Porphyra with too bright purple may be dyed.
Refer to Baidu Encyclopedia-Identification Method of Porphyra Staining
Pharmacological effects of laver
1, the effect on immune function
Porphyra polysaccharide can obviously enhance cellular immunity and humoral immunity, and promote lymphocyte transformation. The dose of 3H-TdR was 2.02 times that of the control group, and that of 3H-UR was 1.28 times that of the control group. Intraperitoneal injection of Porphyra polysaccharide150mg/kg for 7 days in mice can significantly increase the content of serum hemolysin.
Its half hemolysis value (HC50) is 3.64 times higher than that of the control group, indicating that it can enhance humoral immunity. In addition, Porphyra polysaccharide can also enhance the phagocytosis of peritoneal macrophages in mice, increase the weight of immune organs, resist spleen atrophy caused by cyclophosphamide, and have obvious agglutination effect on red blood cells in rats.
2, the impact on the heart
Injection of Porphyra polysaccharide (50mg/kg) into the duodenum of rats can slow down the heart rate, but enhance the myocardial contractility. This effect appeared after the action of Porphyra polysaccharide for 65438 05 minutes and lasted for about 40 minutes.
3. Influence on blood system
Porphyra polysaccharide has obvious anticoagulant effect in vivo and in vitro, and can significantly reduce hemorheological indexes such as whole blood viscosity, plasma viscosity, whole blood reduced viscosity and hematocrit in rabbits. But it can increase the erythrocyte sedimentation rate.
Oral administration of Porphyra polysaccharide 36mg/kg in rabbits can significantly prolong the specific thrombosis time (CTFT) and fibrin thrombosis time (TFT), shorten the length of thrombus, and reduce the wet and dry weight of thrombus, but has no obvious effect on the water content of thrombus. Oral administration of Porphyra polysaccharide 56mg/kg in guinea pigs can significantly shorten globulin dissolution time and enhance fibrinolytic activity.
4. Hypolipidemic effect
Intraperitoneal injection of Porphyra polysaccharide 150mg/kg in mice can prevent the formation of hypercholesterolemia caused by intraperitoneal injection of 75% yolk emulsion 0.5ml, and oral administration of Porphyra polysaccharide 75mg/kg for 8 days can significantly reduce the contents of serum total cholesterol (TC) and triglyceride (TG) in hyperlipidemia model rats caused by eating high-fat and high-cholesterol feed. Feeding Wistar male rats with 10% Porphyra haitanensis can also significantly reduce the serum total cholesterol content of rats fed with high-fat diet.
5. Antitumor effect
Intraperitoneal injection of Porphyra polysaccharide 150mg/kg inhibited S 180 sarcoma in mice, and the inhibition rate reached 47.55%. The inhibitory rate of laver on Ehrlich cancer was 53.2%.
6. Anti-aging effect
Oral administration of 0.2% Porphyra polysaccharide can significantly prolong the average life span of Drosophila melanogaster, increase its flying percentage, and significantly reduce the lipofuscin content of hatched Drosophila melanogaster and 20-day-old Drosophila melanogaster. Intraperitoneal injection of 150mg/kg can reduce lipofuscin content in myocardium by 2 1.69%, increase SOD activity in brain and liver by 55.65% and 54.69% respectively, and prolong swimming time of mice by 86.4 1%. In addition, Porphyra polysaccharide 10mg/kg significantly inhibited the activity of monoamine oxidase B (MAO-B) in isolated mouse brain.
7, anti-radiation effect
After intraperitoneal injection of Porphyra polysaccharide150mg/kg for 7 days, mice were protected from γ -ray irradiation with a total dose of 0.2064 c/kg.
8. Anti-leukopenia effect
Porphyra polysaccharide was injected intraperitoneally into mice at 150mg/kg for 8 days, which obviously antagonized the leukopenia caused by cyclophosphamide, but had no obvious effect on the normal white blood cell count.
9. Hypoglycemic effect
Intraperitoneal injection or oral administration of Porphyra polysaccharide 50mg/kg in mice can significantly reduce normal fasting blood glucose. In alloxan-induced hyperglycemia model in mice, intraperitoneal injection of Porphyra polysaccharide 50 ~ 300 mg/kg has obvious hypoglycemic effect.
10, anti-liver injury effect
Intraperitoneal injection of Porphyra polysaccharide 1.50 mg/kg has obvious antagonistic effect on the increase of serum alanine aminotransferase in mice with carbon tetrachloride liver injury.