The impact of lignin-derived inhibition on enzymatic hydrolysis is investigated by using lignins isolated from untreated woods and pretreated wood pulps. A new method, biomass reconstruction, for which isolated lignins are precipitated onto bleached pulps to mimic lignocellulosic biomass, is introduced, for the first time, to decouple the lignin distribution issue from lignin chemistry. Isolated lignins are physically mixed and reconstructed with bleached pulps. Lignins obtained from pretreated woods adsorb two to six times more cellulase than lignins obtained from untreated woods. The higher adsorption of enzymes on lignin correlates with decreased carbohydrate conversion in enzymatic hydrolysis. In addition, the reconstructed softwood substrate has a lower carbohydrate conversion than the reconstructed hardwood substrate. The degree of condensation of lignin increases significantly after pretreatment, especially with softwood lignins. In this study, the degree of condensation of lignin (0.02 to 0.64) and total OH groups in lignin (1.7 to 1.1) have a critical impact on cellulase adsorption (9 to 70%) and enzymatic hydrolysis (83.2 to 58.2%); this may provide insights into the more recalcitrant nature of softwood substrates.

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Therefore, bornyl acetate and nezukol fractionated from C. japonica essential oil, which showed highly active whitening and antioxidant activities, have potential applications in cosmeceutical materials.

In this study, the antibacterial activity of essential oil from Chamaecyparis obtusa (Sieb. et Zucc) leaves and twigs was investigated. The test strains were Klebsiella pneumoniae, Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, Escherichia coli, Legionella pneumophila, and Methicilline-resistant Staphylococcus aureus. Antibacterial activity was estimated by measuring bacterial growth inhibition. Histopathological examination was also performed. C. obtusa oil distinctly inhibited the growth of all test strains and exhibited the strongest antibacterial activity against L. monocytogenes. It was chromatographically divided into several fractions. The fractions were further tested against antibacterial activity and their chemical compositions were analyzed. The fraction containing terpinen-4-ol (TA) showed high antibacterial activity toward all strains tested. Tests with authentic samples showed that TA played a major role in the antibacterial activity of C. obtusa oil, and in a mice test, the oil actively minimized inflammation by S. aureus.

The sap of Acer mono has been called 'bone-benefit-water' in Korea because of its mineral and sugar content. In particular, the calcium concentration of the sap of A. mono is 37·5 times higher than commercial spring water. In the current study, we examined whether A. mono sap could improve or prevent osteoporosis-like symptoms in a mouse model. Male mice (3 weeks old) were fed a low-calcium diet supplemented with 25, 50 or 100 % A. mono sap, commercial spring water or a high calcium-containing solution as a beverage for 7 weeks. There were no differences in weekly weight gain and food intake among all the groups. Mice that were given a low-calcium diet supplemented with commercial spring water developed osteoporosis-like symptoms. To assess the effect of sap on osteoporosis-like symptoms, we examined serum calcium concentration, and femur density and length, and carried out a histological examination. Serum calcium levels were significantly lower in mice that received a lowcalcium diet supplemented with commercial spring water (the negative control group), and in the 25 % sap group compared to mice fed a normal diet, but were normal in the 50 and 100 % sap and high-calcium solution groups. Femur density and length were significantly reduced in the negative control and 25 % sap groups. These results indicate that a 50 % sap solution can mitigate osteoporosis-like symptoms induced by a lowcalcium diet. We also examined the regulation of expression of calcium-processing genes in the duodenum and kidney. Duodenal TRPV6 and renal calbindin-D9k were up-regulated dose-dependently by sap, and the levels of these factors were higher than those attained in the spring water-treated control. The results demonstrate that the sap of A. mono ameliorates the low bone density induced by a low-calcium diet, most likely by increasing calcium ion absorption.

Polychlorinated biphenyls (PCBs) are difficult to degrade due to poor solubility, toxicity, and thermal stability. In the present study, the feasibility of PCB congener biodegradation by Ceriporia sp. ZLY-2010 was evaluated. The biodegradation rates of four PCB congeners, 4,4'-dichlorobiphenyl, 2,3',4',5-tetrachlorobiphenyl, 2,2',4,5,5'-pentachlorobiphenyl, and 2,2',4,4',5,5'-hexachlorobiphenyl were evaluated. The degradation rate of 4,4'-dichlorobiphenyl was 34.03% on incubation day 13, while that of 2,2',4,4',5,5'-hexachlorobiphenyl reached 40.05% on incubation day 17. Therefore, Ceriporia sp. ZLY-2010 was degrading the higher PCB congeners more efficiently. PCB congener degradation products were extracted using acetone and ethyl acetate. No 2,2',4,5,5'-pentachlorobiphenyl metabolites were detected in Ceriporia sp. ZLY-2010 culture, whereas 2,2',4,4',5,5'-hexachlorobiphenyl appeared to degrade to benzoic acid. However, intermediates of 2,2',4,4',5,5'-hexachlorobiphenyl were not detected during degradation. Therefore, additional studies should be performed to explore the mechanisms of PCB degradation. Our results indicate that Ceriporia sp. ZLY-2010 is able to degrade highly chlorinated biphenyls and has potential for use in PCB biodegradation and bioremediation.