Spatial disinfection potential of slightly acidic electrolyzed water.

Slightly acidic electrolyzed water (SAEW) was developed by Japanese companies over 20 years ago. SAEW has the advantage of potent sterilizing action while being relatively safe. This study evaluated the potential application of SAEW in spatial disinfection. Prior to experiments involving spatial spraying, the ability of SAEW to remove seven type of microorganisms that cause food poisoning was studied in vitro. Results indicated that free chlorine in SAEW, even at a low concentration (30 mg/L), was able to remove Cladosporium cladosporioides, a typical airborne fungus that degrades food, and spores such as Bacillus subtilis, a hardy bacterium. In an experiment involving spatial spraying, 3.43 log10 CFU/100 L of Staphylococcus epidermidis was sprayed in a room-sized space; the same space was then sprayed with SAEW. The number of settling microbes was measured and the sterilizing ability of SAEW was assessed. Results indicated that the concentration of S. epidermidis in the space was completely removed after 20 minutes of SAEW spraying. The above findings indicate that SAEW may be used to remove airborne microorganisms via spatial spraying.

Effectiveness of slightly acidic electrolyzed water on bacteria reduction: in vitro and spray evaluation.

Bacterial inactivation is a crucial aspect of sanitation and hygiene. The effectiveness of slightly acidic electrolyzed water (SAEW) for reduction or removal of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus epidermidis was evaluated. The bactericidal activity of SAEW and sodium hypochlorite (NaOCl) against E. coli and P. aeruginosa were compared through in vitro experiments. The effectiveness of SAEW spray was tested against S. epidermidis. Results showed that SAEW had a more powerful bactericidal activity than NaOCl at the same available chlorine concentrations. For E. coli, SAEW decreased the bacterial counts from 8.4 log10 CFU/mL to less than 3.9 log10 CFU/mL; NaOCl with the same available chlorine of 0.5 mg/L, caused a decrease from 8.4 log10 CFU/mL to 7.1 log10 CFU/mL. For P. aeruginosa, SAEW caused bacterial counts to decrease from 8.5 log10 CFU/mL to less than 4.1 log10 CFU/mL against 8.5 log10 CFU/mL to 6.2 log10 CFU/mL for NaOCl with the same available chlorine of 0.5 mg/L. Spray experiments showed that 10 mg/L of SAEW spray decreased the bacterial counts of S. epidermidis from 3.7 log10 CFU/m3 to 2.8 log10 CFU/m3, with 20 mg/L causing a reduction from 3.8 log10 CFU/m3 to 0 CFU/m3. The overall findings of this study indicate that SAEW may be a promising disinfectant agent either as a solution or spray.

Euzebya tangerina gen. nov., sp. nov., a deeply branching marine actinobacterium isolated from the sea cucumber Holothuria edulis, and proposal of Euzebyaceae fam. nov., Euzebyales ord. nov. and Nitriliruptoridae subclassis nov.

A tangerine-coloured, Gram-positive actinobacterial strain, designated F10(T), was isolated from the abdominal epidermis of a sea cucumber, Holothuria edulis, collected in seawater off the coast of Japan. A 16S rRNA gene sequence analysis indicated that strain F10(T) was a member of the class Actinobacteria and was most closely related to Nitriliruptor alkaliphilus ANL-iso2(T) (87.4 % sequence similarity). Phylogenetic analyses showed that strain F10(T) represented a novel, deep-rooted, and distinct phylogenetic lineage within the class Actinobacteria and clustered with N. alkaliphilus and uncultured bacteria. The organism had meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan, and rhamnose and galactose as the diagnostic cell-wall sugars. Strain F10(T) contained C16 :0ω7c, C16:0 and C17:1ω8c as the major cellular fatty acids. The predominant isoprenoid quinone was MK-9 (H4).The G+C content of the DNA was 68.3 mol%. Based on data from the current polyphasic study, it is proposed that the new marine isolate be placed in a novel genus and be considered a novel species designated Euzebya tangerina gen. nov., sp. nov. within the new family, order and subclass Euzebyaceae fam. nov., Euzebyales ord. nov. and Nitriliruptoridae subclassis nov. in the class Actinobacteria. The type strain of Euzebya tangerina is F10(T) (=NBRC 105439(T) =KCTC 19736(T)).

Phycisphaera mikurensis gen. nov., sp. nov., isolated from a marine alga, and proposal of Phycisphaeraceae fam. nov., Phycisphaerales ord. nov. and Phycisphaerae classis nov. in the phylum Planctomycetes.

Three strains, FYK2301M01(T), FYK2301M18 and FYK2301M52, all being Gram-negative, spherical, motile and facultatively anaerobic, were isolated from a marine alga (Porphyra sp.) collected on Mikura Island, Japan. Colonies of the strains were circular and pink-pigmented on Marine Agar 2216 (Difco) at 25 degrees C. Cells of the strains reproduced by binary fission. The G+C content of the DNA was 73 mol%. The major isoprenoid quinone was MK-6. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strains are the members of the WPS-1 group (Nogales et al., 2001) comprising no validly described taxa within the phylum Planctomycetes. The highest similarity value of the 16S rRNA gene sequences of the strains to those in the established bacterial taxa was only 78.7% to Planctomyces brasiliensis DSM 5305(T). From the taxonomic data obtained in this study, it is proposed that the new marine isolates be placed in a novel genus and species named Phycisphaera mikurensis gen. nov., sp. nov. within a new family, order and class Phycisphaeraceae fam. nov., Phycisphaerales ord. nov. and Phycisphaerae classis nov. in the phylum Planctomycetes. The type strain of Phycisphaera mikurensis is FYK2301M01(T) (= NBRC 102666(T) = KCTC 22515(T)).

Iamia majanohamensis gen. nov., sp. nov., an actinobacterium isolated from sea cucumber Holothuria edulis, and proposal of Iamiaceae fam. nov.

A novel, Gram-positive bacterial strain, F12(T), was isolated from the abdominal epidermis of a sea cucumber, Holothuria edulis, collected from seawater off the coast of Japan. According to 16S rRNA gene sequence analysis, this strain represents a novel, deep-rooting lineage within the class Actinobacteria and clusters with uncultured bacteria and Acidimicrobium ferrooxidans. Compared to species with validly published names, the highest 16S rRNA gene sequence similarity (89.8 %) was to Acidimicrobium ferrooxidans DSM 10331(T). Phylogenetic analyses showed that strain F12(T) represents a distinct phylogenetic lineage related closely to the genus Acidimicrobium. Strain F12(T) contained MK-9(H(6)) as the major menaquinone, whilst 17 : 0, 17 : 1omega8c, 15 : 0 and 16 : 0 were the major cellular fatty acids. The cell-wall peptidoglycan of strain F12(T) was composed of meso-diaminopimelic acid as the diagnostic diamino acid, alanine and glutamic acid (1 : 2 : 1). The cell-wall sugars detected were rhamnose, mannose, arabinose, galactose and xylose. The G+C content of the DNA was 74.4 mol%. From the taxonomic data obtained in this study, the name Iamia majanohamensis gen. nov., sp. nov. is proposed for the isolate, with type strain F12(T) (=NBRC 102561(T)=DSM 19957(T)). The name Iamiaceae fam. nov. is also proposed for the distinct phyletic line represented by the genus Iamia.

Acanthopleuribacter pedis gen. nov., sp. nov., a marine bacterium isolated from a chiton, and description of Acanthopleuribacteraceae fam. nov., Acanthopleuribacterales ord. nov., Holophagaceae fam. nov., Holophagales ord. nov. and Holophagae classis nov. in the phylum 'Acidobacteria'.

Strain FYK2218(T) was isolated from a specimen of the chiton Acanthopleura japonica, which had been collected from a beach on the Boso peninsula in Japan. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the strain belonged to the phylum 'Acidobacteria'. The most closely related type strains to strain FYK2218(T) were Holophaga foetida TMBS4(T) (83.6 % 16S rRNA gene sequence similarity) and Geothrix fermentans H-5(T) (83.6 %) in subdivision 8 of the 'Acidobacteria'. Cells of FYK2218(T) were motile, rod-shaped, Gram-negative, mesophilic and strictly aerobic. The G+C content of the strain was 56.7 mol%. The strain had isoprenoid quinones MK-6 and MK-7 as major components. Major fatty acids of the strain were iso-C(15 : 0), iso-C(17 : 0), C(16 : 0) and C(20 : 5)omega3c (cis-5,8,11,14,17-eicosapentaenoic acid). From the taxonomic data obtained in this study, it is proposed that the new marine isolate be placed into a novel genus and species named Acanthopleuribacter pedis gen. nov., sp. nov. within the new family, order and class Acanthopleuribacteraceae fam. nov., Acanthopleuribacterales ord. nov. and Holophagae classis nov. The family Holophagaceae fam. nov. is also described. The type strain of Acanthopleuribacter pedis is FYK2218(T) (=NBRC 101209(T) =KCTC 12899(T)).

Sneathiella glossodoripedis sp. nov., a marine alphaproteobacterium isolated from the nudibranch Glossodoris cincta, and proposal of Sneathiellales ord. nov. and Sneathiellaceae fam. nov.

A novel marine bacterium, designated strain MKT133(T), was isolated from the foot epidermis of a nudibranch, Glossodoris cincta (Mollusca), collected in seawater off the coast of Japan at a depth of 4 m. This bacterium was Gram-negative, motile, mesophilic and strictly aerobic, with small rod-shaped cells. Colonies of the strain after 4-5 days incubation on marine agar 2216 at 30 degrees C were less than 1 mm in diameter. The strain required salt for growth and contained Q-10 as the predominant respiratory quinone, C(18 : 1) omega 7c, C(16 : 0) and C(17 : 1) as major cellular fatty acids and C(14 : 0) 3-OH as a hydroxy fatty acid. 16S rRNA gene sequence analysis showed that the isolate had highest similarity to Sneathiella chinensis, with 97.2 % sequence similarity to the type strain. Our phylogenetic analysis also revealed that this clade represents a distinct lineage and forms a deep branch with less than 90 % 16S rRNA gene sequence similarity to the members of the eight known orders within the Alphaproteobacteria. Sufficient differences exist to distinguish this strain from Sneathiella chinensis. The name Sneathiella glossodoripedis sp. nov. is proposed, with the type strain MKT133(T) (=IAM 15419(T) =KCTC 12842(T)). The novel order Sneathiellales ord. nov. and family Sneathiellaceae fam. nov. are proposed for the distinct phyletic line represented by the genus Sneathiella.

Tateyamaria omphalii gen. nov., sp. nov., an alpha-Proteobacterium isolated from a top shell Omphalius pfeifferi pfeifferi.

A Gram-negative, strictly aerobic, coccoid to short rod-shaped marine bacterium strain MKT107(T) was isolated from the molluscan top shell Omphalius pfeifferi pfeifferi collected on the coast of Japan. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain MKT107(T) constitutes a new lineage in alpha-Proteobacteria related to the genera Nereida, Roseobacter, Staleya, Oceanibulbus and Sulfitobacter. Strain MKT107(T) was found to require salt for its growth and to be mesophilic. It contained 18:1omega7c and 16:0 as major cellular fatty acids and 3-OH 10:0 and 3-OH 12:0 as hydroxy fatty acids. The DNA base composition of the isolate was 61.6 mol% G+C. The major quinone was Q-10. Sufficient differences existed to distinguish this strain from currently recognized bacterial genera. Therefore, the isolate is classified as representing a new genus and species, Tateyamaria omphalii gen. nov., sp. nov. (type strain MKT107(T) =IAM 15108(T) =KCTC 12333(T); GenBank accession no. AB193438).

Endozoicomonas elysicola gen. nov., sp. nov., a gamma-proteobacterium isolated from the sea slug Elysia ornata.

A Gram-negative, strictly aerobic, rod-formed bacterium, strain MKT110(T), was isolated from a mollusk, the sea slug Elysia ornata collected in seawater off the coast of Izu-Miyake Island, Japan at a depth of 15m. Comparative 16S rRNA gene sequences analysis indicated that the isolate MKT110(T) constituted a novel lineage in gamma-proteobacteria related to the genera Zooshikella, Oceanospirillum, Microbulbifer, Marinobacter, Saccharospirillum and Pseudomonas. The strain MKT110(T) was closely related to the clones from marine sponge Halichondria okadai (AB054136, AB054161) and the coral Pocillopora damicornis (AY700600, AY700601). The phylogenetic tree based on the 16S rRNA gene sequences showed that MKT110(T) and four clones formed a sub-lineage related to the genus Zooshikella, with a bootstrap value of 100%. MKT110(T) required salt for its growth and was mesophilic. The bacterium contained 16:1omega7c, 16:0 and 14:0 as major cellular fatty acids, and 3-OH 14:0, 3-OH 10:0 and 3-OH 12:0 as major hydroxy fatty acids. The DNA base composition of the isolate was 50.4 mol% G+C. The major quinone was Q-9. The bacterium is distinguished from currently recognized bacterial genera based on phylogenetic and phenotypic features and should be classified in a novel genus for which the name Endozoicomonas elysicola gen. nov., sp. nov. is proposed. (type strain MKT110(T)=IAM 15107(T)=KCTC 12372(T); GenBank accession no. AB196667).

Pseudovibrio ascidiaceicola sp. nov., isolated from ascidians (sea squirts).

Two bacterial strains, F423T and F10102, were isolated from two ascidians, Polycitor proliferus and Botryllidae sp., respectively, which were collected from a beach on the Boso peninsula in Japan. Cells of both isolates were motile, rod-shaped and formed star-shaped aggregates in the early stage of exponential growth, but were coccoid in stationary growth phase. The results of 16S rRNA gene sequence analysis, fatty acid analysis, DNA-DNA hybridization experiments and physiological and biochemical tests indicated that the two strains were members of a novel species of the genus Pseudovibrio for which the name Pseudovibrio ascidiaceicola sp. nov. is proposed. The type strain is F423T (=NBRC 100514T=IAM 15084T=DSM 16392T=KCTC 12308T).

Agarivorans albus gen. nov., sp. nov., a gamma-proteobacterium isolated from marine animals.

Six bacterial strains were isolated from healthy marine organisms that were collected from the coast of the Kanto area in Japan. Phylogenetic analysis based on 16S rDNA sequence similarity showed that the six isolates formed a separate cluster in the gamma-Proteobacteria and were related to the genera Alteromonas and Glaciecola (<91.6 % similarity). The isolates were related closely to each other (DNA-DNA reassociation values of 74-93 %). The isolates had a polar flagellum and were Gram-negative, mesophilic, strictly aerobic rods that required salt for growth. Distinct phenotypic features of this group included the ability to hydrolyse agar and white pigmentation of colonies. The DNA G+C content of the isolates was 48-50 mol%. The major quinone was Q-8. Phenotypic characteristics of the isolates differed from those of members of the genera Alteromonas and GLACIECOLA: The name Agarivorans albus gen. nov., sp. nov. is proposed for the six isolates; the type strain is MKT 106(T) (=IAM 14998(T)=LMG 21761(T)).

A preliminary report of phylogenetic diversity of bacterial strains isolated from marine creatures.

Bacterial diversity among marine creatures, especially molluscs, as a source for searching out novel lineages of bacteria, was studied. Marine creatures were collected at the coasts of the Kanto area in Japan. A total of 116 strains of bacteria were isolated from the intestines of 19 species of marine creatures includings molluscs, pisces and protochordata. Partial sequencing of 16S rDNA revealed that most of the isolates belonged to the gamma subclass of the Proteobacteria and Cytophaga-Flavobacterium-Bacteroides group. The BLAST searches revealed that the complete 16S rDNA sequence of 17 strains out of 116 isolates showed less than 94% similarity with 16S rDNA sequences deposited in the database. Four strains out of the 17 isolates belonged to the Rhodobacter group, 8 strains to the Alteromonas group, and the remaining 5 strains to the Cytophaga-Flavobacterium-Bacteroides group. Phylogenetic positions of 6 strains belonging to the Alteromonas group, which were isolated from different marine creatures, were close to each other, and represented a novel 16S rDNA lineage within the gamma subclass of Proteobacteria. Therefore, it may be inferred that these 6 strains belong to a new genus of Proteobacteria. Phylogenetic positions of the other strains are also independent from neighboring taxa, and they were suggested to respectively form a novel lineage. From these results, it is clear that the biodiversity of bacteria in marine creatures is much wider than was previously thought, and unknown microbiological resources are buried in these organisms.