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The accumulation of saccharides and fructooligosaccharides (FOS) in the individual leaf-bases of onion ( Allium cepaL.) was investigated during growth and bulb development. Saccharides and FOS were analysed by means of high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD). The glucose content was the highest, while the content of saccharides (glucose, fructose and sucrose) increased during June, July and August and decreased slightly during September. The trisaccharides all accumulated to a similar extent, although the neokestose [ 3b, 6 G- β-D fructofuranosylsucrose] content was higher than that of 1-kestose [ 3a, 1 F- β-D-fructofuranosylsucrose]. Tetra-, penta- and high-DP (degree of polymerization) FOS also showed a similar pattern, though the contents of 4b[6 G(1- β-D-fructofuranosyl) 2sucrose] and 5b[6 G(1- β-D-fructofuranosyl) 3sucrose] were higher compared with that of other tetra-[ 4a, 1 F(1- β-D-fructofuranosyl) 2sucrose and 4c, 1 F, 6 G-di- β-D-fructofuranosyl sucrose] and penta-saccharides [ 5a, 1 F(1- β-D-fructofuranosyl) 3sucrose]. Total FOS accumulated to a greater extent in the inner (youngest) leaf-bases than in the outer (oldest) leaf-bases, and their content was high during August. The total carbohydrates content was 6.71, 7.25, 8.10 and 6.30 g 100 g −1FW during June, July, August and September, respectively. During bulb formation, a balance was observed between the glucose, fructose, sucrose and FOS contents, with an average ratio of 20:10:10:60 of total carbohydrates, respectively.

The Aquatic fern Azolla was used to treat waste water. Because of the capability of N fixation by Azolla, the efficient removal of phosphorus would be expected even after N is consumed. Azolla in outdoor batch cultures actively absorbed nutrients from the secondary treated effluent from May to October. The best growth with 2.5 days doubling time and the highest nutrient absorption were observed when tne P level was higher than the N level. The absorption capacity of Azolla was lower for nitrogen and higher for P than those of any other aquatic plants so far reported.Subsequent analysis of chemical composition of Azolla suggested that it would be a good biomass source of green manure and animal feed. Although the test diet, 20% dried Azolla, gave a poorer weight gain in male rats than commercial diet, in female the same effect of both diets was observed. No abnormal symptoms were found in 5 organs and in the blood examinations in rats fed with Azolla diet. In a feeding experiment with Tilapia nilotica, the diet containing dried Azolla as 16.6% of the total weight showed the same effects on percent weight gain and feed efficiency when compared with the control diet which included casein as a protein source. However, both effects of Azolla on Tilapia declined with increasing rate of Azolla content in tne diets.

DNA methylation was examined in xeroderma pigmentosum (XP) cells. The amount of 5-methylcytosine (mC) in DNA from XP cells was about 70% of that in DNA from normal controls. Southern hybridization analysis showed that the HLA-DRα gene in XP lymphocyte B cells was differently methylated from normals, but its expression was apparently unaffected. The methylation of dihydrofolate reductase, a housekeeping gene, was the same as in controls. The revertants to UV resistance from XP fibroblasts recovered a methylation level close to that of normal cells. Results suggested that XP DNA was undermethylated non-randomly, and that DNA methylation might be associated with DNA repair function.

An ethionine-resistance gene cloned from Saccharomyces cerevisiae DKD-5D-H was able to enhance S-adenosyl-l-methionine (AdoMet) accumulation when it was introduced into the yeast cells on multi-copy plasmid YEp13. In order to increase the AdoMet accumulation, the gene was integrated into the yeast chromosome by using a yeast transposon Ty element. When the YEp plasmid was used for the integration, the ethionine-resistance gene was efficiently inserted into the yeast chromosomes with a substantial increase in AdoMet productivity (about twofold) in comparison with that by the yeast cells carrying the gene on an extrachromosomal multi-copy plasmid.