Development of the production of 2-pyrone-4,6-dicarboxylic acid from lignin extracts, which are industrially formed as by-products, as raw materials.

Lignosulfonate is a by-product of the cooking process by sulfite pulping for paper manufacturing. The treatment of wood chips by various salts of sulfurous acid solubilizes lignin to produce a cellulose-rich wood pulp. Developing a technique for the conversion of lignosulfonate by-product to high value materials has an important industrial utility. Sphingobium sp. strain SYK-6, which was isolated from pulping wastewater, is one of the best enzymatically or genetically characterized bacteria for degrading lignin-derived aromatics. We have previously established a system for the production of 2-pyrone-4,6-dicarboxylic acid (PDC), a novel platform chemical that can produce a variety of bio-based polymers, by introducing of ligA, ligB, and ligC genes from SYK-6 into a mutant strain of Pseudomonas putida PpY1100. In this study, extracts from lignosulfonates, which were desulphonated and depolymerized by alkaline oxidation, were evaluated as substrates for microbiological conversion to PDC by the transgenic bacteria.

Identification of a hydrolyzable tannin, oenothein B, as an aluminum-detoxifying ligand in a highly aluminum-resistant tree, Eucalyptus camaldulensis.

Eucalyptus camaldulensis is a tree species in the Myrtaceae that exhibits extremely high resistance to aluminum (Al). To explore a novel mechanism of Al resistance in plants, we examined the Al-binding ligands in roots and their role in Al resistance of E. camaldulensis. We identified a novel type of Al-binding ligand, oenothein B, which is a dimeric hydrolyzable tannin with many adjacent phenolic hydroxyl groups. Oenothein B was isolated from root extracts of E. camaldulensis by reverse-phase high-performance liquid chromatography and identified by nuclear magnetic resonance and mass spectrometry analyses. Oenothein B formed water-soluble or -insoluble complexes with Al depending on the ratio of oenothein B to Al and could bind at least four Al ions per molecule. In a bioassay using Arabidopsis (Arabidopsis thaliana), Al-induced inhibition of root elongation was completely alleviated by treatment with exogenous oenothein B, which indicated the capability of oenothein B to detoxify Al. In roots of E. camaldulensis, Al exposure enhanced the accumulation of oenothein B, especially in EDTA-extractable forms, which likely formed complexes with Al. Oenothein B was localized mostly in the root symplast, in which a considerable amount of Al accumulated. In contrast, oenothein B was not detected in three Al-sensitive species, comprising the Myrtaceae tree Melaleuca bracteata, Populus nigra, and Arabidopsis. Oenothein B content in roots of five tree species was correlated with their Al resistance. Taken together, these results suggest that internal detoxification of Al by the formation of complexes with oenothein B in roots likely contributes to the high Al resistance of E. camaldulensis.

[Case report of a liver metastasis from rectal cancer achieving complete response (CR) by a combination of intra-hepatic arterial infusion of irinotecan (CPT-11) with degradable starch microspheres (DSM) and weekly high-dose intra-hepatic arterial chemotherapy with 5-FU].

A 67-year-old woman, who was diagnosed with rectal cancer and liver metastasis, underwent a low anterior resection of the rectum in May 2004. Two months later, the level of tumor markers increased and a CT scan revealed a 45 x 35 mm liver metastasis in the S(8) segment. She was referred to our hospital for treatment of the liver tumor. Intra-hepatic arterial infusion of irinotecan (CPT-11) and mitomycin C (MMC) with degradable starch microspheres (DSM) was given in July 2004. Following this, a 34-week course of weekly high-dose intra-hepatic arterial 5-FU infusion (5-FU 1,000 mg/m(2)) was performed. In April 2005, the size of the liver metastasis decreased, and the level of serum tumor marker normalized. A CT and echo scan revealed a calcified tumor, and therefore all chemotherapy was stopped. She was followed in the outpatient clinic, with no evidence of recurrence for 12 months. This case suggests that the use of intra-hepatic arterial infusion of CPT-11 and MMC with DSM is useful for the treatment of liver metastases in colorectal cancer.