Studies On Biological Activity Of Walnut Endophyte’s Fermentation Products And Chemical Composition Of Walnut Inflorescence

Juglans is a ornamental plant, and widely distributed in many parts of China. Its leaves, inflorescences, bark, root, wood have been used as traditional herb medicine for treatment of many diseases. In this thesi, we mainly studied the chemical constitutes and biological activity of the inflorescence of Juglans regia and the biological activity of metabolites from endophytic fungi which isolated from the root, stem and leaves of Juglans regia. The results were as follows:Part I:Antibacterial activity of ethanol extracts from the inflorescence of Juglans regia was determined by filter paper method, and we found EtOAc parts showed the strongest activity. Antioxidant activity was evaluated by DPPH radical scavenging, hydroxyl radical scavenging and total reducing power, respectively. The results that EtOAc parts showed the best DPPH and hydroxyl radical scavenging activity, while n-BuOH parts performance best in total reducing power test. The phytochemical investigation of the inflorescence of Juglans regia was studied by chromatographic separation methods and modern spectroscopic techniques,9 compounds were isolated and identified: 1-(1-methyl-3-enyl)-2-(1,1-dimethyl-propoxy)-4-toluene (1), P-sitosterol (2), Isosclerone (3), (Z)-7-acetoxy-methyl-11-methyl-3-methylenedodeca-1,6,10-triene (4),2S,3S,4S-trihydroxy acid (5),3-methoxy-2-[3-hydroxyphenyl]-4H-furo[2,3-H]-1-benzopy ran-4-one (6), quercetin-3-O-(2"-β-D-glucopyranosyl)-a-L-rhamnoside (7).Part II:19 strains of endophytic fungus were isolated, in which 7 strains from root,5 strains from stems and the rest from leaves. Morphological identification is carried out with eight sporogenic endophytic fungi. They were preliminary identified as follows:2 strains were to Fusarium,2 strains were to Penicillium sp.,1 strain was to Monilia,1 strain was to Sporotrichum Lk.,1 strain was to Stemphylium,1 strain was to Microascus. The result of 8 strains spore produced endophytic fungus of Juglans regia were premilinary identified were showed that:8 strains belows to 6 genus,4 famiy,3 order,3 class.Part III:Antimicrobial and antioxidant activity of metabolites from endophytic fungi were analyzed with the same method as previous. The results show that metabolites from 6 strains,31.57% of the total, have better antimicrobial activity against five tested bacteria. Among them, the MIC of metabolite from R-401 against Staphyloccocus aureus, Pseudomonas aerμginosa, Streptococcus pneumonia is low to 0.313mg/mL and MIC of metabolite from S-101 against Bnfillus licheniformis is low to 0.313mg/mL.9 samples, 47.36% of the total, show good DPPH radical scavenging activity (Clearance more than 50%). While, hydroxyl radical scavenging activity is generally poor and only the clearance of samples from R302 and S-101 are more than 50%. All samples exhibited a certain degree of reducing power; Vc equivalent of samples from R-401 is 157.66μg/mg, while others are less than 100μg/mg.The above results show that the chemical compositions of Juglans regia were diverse, endophytes have numerous populations, and fermentation products had good antibacterial and antioxidant activity.