Wood Extractives of Silver Fir and Their Antioxidant and Antifungal Properties.

The chemical composition of extractives in the sapwood (SW), heartwood (HW), knotwood (KW), and branchwood (BW of silver fir (Abies alba Mill.) was analyzed, and their antifungal and antioxidant properties were studied. In addition, the variability of extractives content in a centripetal direction, i.e., from the periphery of the stem towards the pith, was investigated. The extracts were analyzed chemically with gravimetry, spectrophotometry, and chromatography. The antifungal and antioxidative properties of the extracts were evaluated by the agar well diffusion method and the diphenyl picrylhydrazyl radical scavenging method. Average amounts of hydrophilic extractives were higher in KW (up to 210.4 mg/g) and BW (148.6 mg/g) than in HW (34.1 mg/g) and SW (14.8 mg/g). Extractives identified included lignans (isolariciresinol, lariciresinol, secoisolariciresinol, pinoresinol, matairesinol) phenolic acids (homovanillic acid, coumaric acid, ferulic acid), and flavonoids epicatechin, taxifolin, quercetin). Secoisolariciresinol was confirmed to be the predominant compound in the KW (29.8 mg/g) and BW (37.6 mg/g) extracts. The largest amount of phenolic compounds was extracted from parts of knots (281.7 mg/g) embedded in the sapwood and from parts of branches (258.9 mg/g) adjacent to the stem. HW contained more lignans in its older sections. Hydrophilic extracts from knots and branches inhibited the growth of wood-decaying fungi and molds. KW and BW extracts were better free radical scavengers than HW extracts. The results of the biological activity tests suggest that the protective function of phenolic extracts in silver fir wood can also be explained by their antioxidative properties. The results of this study describe BW as a potential source of phenolic extractives in silver fir.

Rhamnolipid-assisted mycoremediation of polycyclic aromatic hydrocarbons by Trametes hirsuta coupled with enhanced ligninolytic enzyme production.

The present study deals with the development of a wood assisted fungal system (WAFS) from wood chips using Trametes hirsuta to remove polycyclic aromatic hydrocarbons (PAHs) in BRW. The WAFS exhibited a 1.4-fold higher ligninolytic enzyme production than free fungi in the effluent. Further, to understand PAHs bioremediation by T. hirsuta, biodegradation along with biosorption were studied in model PAHs, phenanthrene (Phe) and benzo (a) pyrene (BaP), in the presence of synthesized rhamnolipids. The WAFS mineralized up to an average of 91.26% Phe and 87.72 % BaP along with biosorption of 12.35% Phe and 18.36 % BaP within 12 days. Thus, the addition of rhamnolipids showed 1.2-fold enhanced biodegradation. However, rhamnolipid concentrations beyond 50 ppm reduced the degradation efficiency of WAFS. Moreover, the degradation capability of total aromatic hydrocarbon (TAH) in biorefinery wastewater by WAFS is 1.8-fold higher than that of free fungi, which confirms the effectiveness of the system. Implications: Simultaneous application of white-rot fungus along with surfactant into a pollutant environment affects the microenvironment of the fungus and reduces the production of their degradative enzymes. In addition, the requirement of periodical supplement of external nutrient in the real-time matrix for the growth of white rot fungi may trigger competitive growth of indigenous microorganisms. Considering this glitch, the current work utilizes the carpenter waste for the strategical develop a wood assisted fungal system to protect the microenvironment of the fungi in the presence of rhamnolipids and contribute to their survival in real time matrix, with enhanced PAHs degradation efficiency.

[Separation and regeneration of protoplast from Phellinus igniarius].

OBJECTIVE: To study the conditions on separation and regeneration of protoplast from Phellinus igniarius. METHOD: The effects of enzymolysis conditions of P. igniarius mycelia on yield of protoplast and culturing conditons on regeneration ratio of protoplast were investigated. RESULT: When the 8 days-old mycelia was hydrolysed by 1.5% of lywallzyme adding to driselase of 0. 5% and at 30 degrees C for 3 h and enzymolysis was stablized by sucrose as a stablisher of osmotic pressure, higher yield of P. igniarius protoplast was obtained. If 10 days-old mycelia was used as raw material of enzymolysis and manntol was selected as stablisher of osmotic pressure of enzymolysis, higher regeneration ratio of P. igniarius protoplast also would be obtained in following regeneration step at same time keeping higher yield. For the regeneration processing, it was beneficial for the regeneration of P. igniarius protoplast that PDA plusing mulberry ramulus was used as the culture medium of regeneration and manntol was selected as the osmotic pressure establisher of regeneration culture medium. CONCLUSION: The method and conditions to keep both higher yield and regeneration ratio of P. igniarius protoplast were obtained.

Carbon and nitrogen sources influence the ligninolytic enzyme activity of Trametes versicolor.

Among carbon sources studied, cellobiose and mannitol provided the highest laccase (Lac) activity (648 and 742 U1(-1), respectively) of Trametes versicolor 775 while glucose gave maximum manganese peroxidase (MnP) and peroxidase activities (44 and 114 U1(-1), respectively). Citrus fruit peel as growth substrate enhanced Lac activity 7-fold when compared to the medium with cellobiose, whereas grape vine sawdust increased MnP and peroxidase activity up to 148 and 677 U1(-1), respectively.

New antifungal bithienylacetylenes from Blumea obliqua.

Two new bioactive bithienylacetylenes isolated from Blumea obliqua have been characterized as 5'-methyl-5-[4-(3-methyl-1-oxobutoxy)-1-butynyl]-2,2'- bithiophene [1] and 5'-hydroxymethyl-5-[butyl-3-en-1-yn]-2,2'-bithiophene isovaleroxy ester [2], respectively. Compounds 1 and 2 showed antifungal activity against Epidermophyton floccosum and Pleurotus ostreatus.