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To confirm the growth inhibition effect of immobilized pectinase on algae, co-cultivation method was used to investigate the effect of immobilized pectinase on the growth of Microcystis aeruginosa. After co-cultivation, the damage status of the algae was observed through electron microscope, and the effect of immobilized pectase on the physiological and biochemical characteristics of the algae was also measured. The results showed that the algae and immobilized pectase co-cultivated solution etiolated distinctly on the third day and there was a significantly positive correlation between the extent of etiolation and the dosage as well as the treating time of the immobilized pectinase. Under electron microscope, plasmolysis was found in the slightly damaged cells, and the cell surface of these cells was rough, uneven and irregular; the severely damaged cells were collapsed or disintegrated completely. The algal yield and the chlorophyll a content decreased significantly with the increase of the treating time. The measurement of the malondiadehyde (MDA) value showed that the antioxidation system of the treated algal cells was destroyed, and their membrane lipid was severely peroxidated. The study indicated that the immobilized pectinase could efficiently inhibit the growth of M. aeruginosa, and the inhibitory rate reached up to 96%.

Two rod-shaped, non-motile bacteria were isolated from two separate salt mines in Yunnan, south-western China. These strains, designated YIM D15T and YIM J21T, were Gram-negative and moderately halophilic. The two strains required 6–10 % NaCl (w/v; optimal) for growth. The DNA G+C contents of strains YIM D15T and YIM J21T were 49.0 mol% and 48.4 mol%, respectively. The predominant isoprenoid quinone was MK-7. The polar lipid profiles of strains YIM D15T and YIM J21T were composed predominantly of diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, three unknown polar lipids and one glycolipid. Minor amounts of other lipids were also detectable. The predominant cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 1ω9c/10 methyl-C16 : 0 and C16 : 1ω7c/C16 : 1ω6c. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that the two isolates formed a distinct clade with the genus Fodinibius (in the phylum Bacteroidetes ) and were related to the species Fodinibius salinus , with sequence similarities of 91.9–92.4 %. Analyses of 16S rRNA gene sequences revealed that strains YIM D15T and YIM J21T were related to each other (97.3 % sequence similarity). The DNA–DNA hybridization relatedness between the two isolates was 34 %. On the basis of the phylogenetic analysis, DNA–DNA hybridization relatedness, phenotypic and chemotaxonomic characteristics, strains YIM D15T and YIM J21T should be classified as members of a novel genus and as two novel species, for which the names Aliifodinibius roseus gen. nov., sp. nov. (type strain YIM D15T = ACCC 10715T = KCTC 23442T) and Aliifodinibius sediminis sp. nov. (type strain YIM J21T = ACCC 10714T = DSM 21194T) are proposed.

A novel, moderately halophilic, rod-shaped bacterium, designated strain YIM D17T, was isolated from a sample of sediment from a salt mine in Yunnan, south-western China. The taxonomy of strain YIM D17T was investigated using a polyphasic approach. Strain YIM D17T was Gram-stain-negative, strictly aerobic and non-motile and formed pink colonies on marine agar. Optimal growth occurred at 37 °C, pH 7.5–8.0 and in the presence of 10–15 % (w/v) NaCl. The major menaquinone was MK-7. The polar lipid profile was composed predominantly of diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, one phospholipid, one glycolipid and one aminolipid. Minor amounts of other lipids were also detectable. The predominant cellular fatty acids were iso-C17 : 1ω9c/10-methyl-C16 : 0 (24.0 %), iso-C15 : 0 (23.6 %) and C16 : 1ω7c/C16 : 1ω6c (13.8 %). The DNA G+C content was 43.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that the isolate formed a distinct clade with the genera Gracilimonas and Balneola (both in the phylum Bacteroidetes) and was related to the species Gracilimonas tropica, Balneola vulgaris and Balneola alkaliphila, with sequence similarities of 85.6 %, 83.0 % and 82.8 % to the respective type strains. On the basis of its phenotypic, chemotaxonomic and phylogenetic features, strain YIM D17T represents a novel species of a new genus, for which the name Fodinibius salinus gen. nov., sp. nov. is proposed. The type strain is YIM D17T ( = ACCC 10716T = DSM 21935T).

Three nematicidal cardenolides were obtained from the AcOEt extract of Nerium indicum Mill. by bioassay-guided fractionation. They include a new compound, 3beta-O-(beta-D-diginosyl)-14,15alpha-dihydroxy-5alpha-card-20(22)-enolide (1), and two known compounds, uzarigenin (2) and cardenolide N-1 (3). The median lethal concentrations (LC(50)) of compounds 1-3 against the nematodes Bursaphelenchus xylophilus, Panagrellus redivivus, and Caenorhabditis elegans at 72 h were 103.3, 49.0, and 45.4 mg l(-1), 257.0, 62.7, and 177.8 mg l(-1), and 242.9, 29.1, and 41.7 mg l(-1), respectively. This is the first report about the nematicidal activity of cardenolides.