Characterization of oleaginous yeasts accumulating high levels of lipid when cultivated in glycerol and their potential for lipid production from biodiesel-derived crude glycerol.

This study attempted to identify oleaginous yeasts and selected the strain that accumulated the largest quantity of lipid for lipid production from glycerol. Two-step screening of 387 yeast strains revealed 23 oleaginous strains that accumulated quantities of lipid higher than 20 % of their biomass when cultivated in glycerol. These strains were identified to be four ascomycetous yeast species i.e. Candida silvae, Kodamaea ohmeri, Meyerozyma caribbica, and Pichia manshurica, and five basidiomycetous yeast species i.e. Cryptococcus cf. podzolicus, Cryptococcus laurentii, Rhodosporidium fluviale, Rhodotorula taiwanensis, and Sporidiobolus ruineniae. Rhodosporidium fluviale DMKU-RK253 accumulated the highest quantity of lipid equal to 65.2 % of its biomass (3.9 g L(-1) lipid and 6.0 g L(-1) biomass) by shaking flask cultivation in crude glycerol. The main fatty acids in the accumulated lipid of this strain consisted of oleic acid, linoleic acid, and palmitic acid. Therefore, R. fluviale DMKU-RK253 has potential for producing lipid for biodiesel manufacturing using crude glycerol as a feedstock.

Barnettozyma siamensis f.a., sp. nov., a lipid-accumulating ascomycete yeast species.

Two strains, DMKU-UbN24(1)(T) and DMKU-CPN24(1), of a novel yeast species were obtained from soil and palm oil fruit, respectively, collected in Thailand by an enrichment isolation technique using a nitrogen-limited medium containing glycerol as the sole source of carbon. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, the two strains were found to represent a novel species of the genus Barnettozyma although the formation of ascospores was not observed. The novel species was related most closely to the type strain of Candida montana but differed by 5.4 % nucleotide substitutions in the D1/D2 region of the LSU rRNA gene and by 10.3-10.5 % nucleotide substitutions in the ITS region. The name Barnettozyma siamensis f.a., sp. nov. is proposed. The type strain is DMKU-UbN24(1)(T) ( = BCC 61189(T) = NBRC 109701(T) = CBS 13392(T)).

Diversity of culturable yeasts in phylloplane of sugarcane in Thailand and their capability to produce indole-3-acetic acid.

Yeasts were isolated by the enrichment technique from the phylloplane of 94 samples of sugarcane leaf collected from seven provinces in Thailand. All sugarcane leaf samples contained yeasts and 158 yeast strains were obtained. On the basis of the D1/D2 domain of the large subunit rRNA gene sequence analysis, 144 strains were identified to 24 known species in 14 genera belonging to the Ascomycota viz. Candida akabanensis, Candida dendronema, Candida mesorugosa, Candida michaelii, Candida nivariensis, Candida rugosa, Candida orthopsilosis, Candida quercitrusa, Candida tropicalis, Candida xylopsoci, Cyberlindnera fabianii, Cyberlindnera rhodanensis, Debaryomyces nepalensis, Hannaella aff. coprosmaensis, Hanseniaspora guilliermondii, Kluyveromyces marxianus, Lachancea thermotolerans, Lodderomyces elongisporus, Metschnikowia koreensis, Meyerozyma caribbica, Millerozyma koratensis, Pichia kudriavzevii, Torulaspora delbrueckii and Wickerhamomyces edaphicus, and 12 species in six genera of the Basidiomycota viz . Cryptococcus flavescens, Cryptococcus laurentii, Cryptococcus rajasthanensis, Kwoniella heveanensis, Rhodosporidium fluviale, Rhodosporidium paludigenum, Rhodotorula mucilaginosa, Rhodotorula sesimbrana, Rhodotorula taiwanensis, Sporidiobolus ruineniae, Sporobolomyces carnicolor and Sporobolomyces nylandii. Seven strains were identical or similar to four undescribed species. Another seven strains represented four novels species in the genus Metschnikowia, Nakazawaea, Wickerhamomyces and Yamadazyma. The results revealed 69 % of the isolated strains were ascomycete yeasts and 31 % were basidiomycete yeast. The most prevalent species was M. caribbica with a 23 % frequency of occurrence followed by Rh. taiwanensis (11 %) and C. tropicalis (10 %). All strains were assessed for indole-3-acetic acid (IAA) producing capability showing that 69 strains had the capability of producing IAA when cultivated in yeast extract peptone dextrose broth supplemented with 1 g/L L-tryptophan. The highest IAA concentration of 565.1 mg/L was produced by R. fluviale DMKU-RK253.

Yamadazyma siamensis sp. nov., Yamadazyma phyllophila sp. nov. and Yamadazyma paraphyllophila sp. nov., three novel yeast species isolated from phylloplane in Thailand and Taiwan.

Four strains representing three novel anamorphic yeast species were isolated from the external surface of sugarcane leaves (DMKU-RK254(T)), corn leaves (DMKU-RK548(T)), bean leaves (K129) in Thailand and hengchun pencilwood leaves (TrB1-1(T)) in Taiwan. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene, the internal transcribed spacer (ITS) region, the actin gene (ACT1) and the elongation factor 2 gene (EF2), the four strains were determined to represent novel Yamadazyma species although formation of ascospores was not observed. Strain DMKU-RK254(T) was determined to be related to Candida diddensiae, Candida naeodendra and Candida kanchanaburiensis but with 1.8, 1.8 and 2.0 % nucleotide substitutions in the D1/D2 region of the LSU rRNA gene, respectively. It was assigned to Yamadazyma siamensis sp. nov. (type strain DMKU-RK254(T) = BCC 50730(T) = NBRC 108901(T) = CBS 12573(T)). The sequences of the D1/D2 region of the LSU rRNA gene, the ITS region, ACT1 gene and EF2 gene of two strains (DMKU-RK548(T) and K129) were identical but differed from that of strain TrB1-1(T) by 0.6, 1.0, 3.3 and 5.9 % nucleotide substitutions, respectively. Therefore, the two strains (DMKU-RK548(T) and K129) and strain TrB1-1(T) were assigned to be two separate species. The closest species in terms of pairwise sequences similarity of the D1/D2 region to the two novel species was Yamadazyma philogaea but with 1.1-1.7 % nucleotide substitutions. The two strains (DMKU-RK548(T) and K129) were assigned to Yamadazyma phyllophila sp. nov. (type strain DMKU-RK548(T) = BCC 50736(T) = NBRC 108906(T) = CBS 12572(T)) and the strain TrB1-1(T) was named Yamadazyma paraphyllophila sp. nov. (type strain TrB1-1(T) = BCRC 23030(T) = CCTCC AY 204005(T) = CBS 9928(T)).

Selection and characterization of a newly isolated thermotolerant Pichia kudriavzevii strain for ethanol production at high temperature from cassava starch hydrolysate.

Pichia kudriavzevii DMKU 3-ET15 was isolated from traditional fermented pork sausage by an enrichment technique in a yeast extract peptone dextrose (YPD) broth, supplemented with 4 % (v/v) ethanol at 40 °C and selected based on its ethanol fermentation ability at 40 °C in YPD broth composed of 16 % glucose, and in a cassava starch hydrolysate medium composed of cassava starch hydrolysate adjusted to 16 % glucose. The strain produced ethanol from cassava starch hydrolysate at a high temperature up to 45 °C, but the optimal temperature for ethanol production was at 40 °C. Ethanol production by this strain using shaking flask cultivation was the highest in a medium containing cassava starch hydrolysate adjusted to 18 % glucose, 0.05 % (NH(4))(2)SO(4), 0.09 % yeast extract, 0.05 % KH(2)PO(4), and 0.05 % MgSO(4)·7H(2)O, with a pH of 5.0 at 40 °C. The highest ethanol concentration reached 7.86 % (w/v) after 24 h, with productivity of 3.28 g/l/h and yield of 85.4 % of the theoretical yield. At 42 °C, ethanol production by this strain became slightly lower, while at 45 °C only 3.82 % (w/v) of ethanol, 1.27 g/l/h productivity and 41.5 % of the theoretical yield were attained. In a study on ethanol production in a 2.5-l jar fermenter with an agitation speed of 300 rpm and an aeration rate of 0.1 vvm throughout the fermentation, P. kudriavzevii DMKU 3-ET15 yielded a final ethanol concentration of 7.35 % (w/v) after 33 h, a productivity of 2.23 g/l/h and a yield of 79.9 % of the theoretical yield.

Influence of Acetobacter pasteurianus SKU1108 aspS gene expression on Escherichia coli morphology.

The aspS gene encoding Aspartyl-tRNA synthetase (AspRS) from a thermotolerant acetic acid bacterium, Acetobacter pasteurianus SKU1108, has been cloned and characterized. The open reading frame (ORF) of the aspS gene consists of 1,788 bp, encoding 595 amino acid residues. The highly conserved Gly-Val-Asp-Arg ATP binding motif (motif 3) is located at the position 537-540 in the C-terminus. Deletion analysis of the aspS gene upstream region suggested that the promoter is around 173 bp upstream from the ATG initiation codon. Interestingly, transformation with the plasmids pGEM-T138, pUC138, and pCM138 synthesizing 138 amino acid C-terminal fragments of AspRS, that carry the ATP binding domain, caused E. coli cell lengthening at 37 and 42°C. Moreover, E. coli harboring pUC595 (synthesizing all 595 amino acids) and a disordered aspS gene in pGEM-T138 had normal rod shapes. The normal rod shape was observed in E. coli harboring pD539V following site-directed mutagenesis of the ATP binding domain. We propose that over-production of truncated C-terminal peptides of AspRS may cause sequestration of intracellular ATP in E. coli, leaving less ATP for cell division or shaping cell morphology.

Metschnikowia saccharicola sp. nov. and Metschnikowia lopburiensis sp. nov., two novel yeast species isolated from phylloplane in Thailand.

Five strains representing two novel anamorphic yeast species were isolated from the external surface of sugarcane leaves (DMKU-RK16, DMKU-RK24, DMKU-RK198 and DMKU-RK500(T)) and rice leaf (DMKU-RK277(T)) by an enrichment technique. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and the internal transcribed spacer region, the five strains were assigned to be two novel species of the Metschnikowia, although the formation of ascospores was not observed. Four strains (DMKU-RK16, DMKU-RK24, DMKU-RK198 and DMKU-RK500(T)) where the sequences of the D1/D2 domain of the LSU rRNA gene were identical and differed by 4.1 % nucleotide substitutions (20 nucleotide substitutions and four gaps out of 490 nt) from the type strain of Candida succicola, their closest known species in terms of pairwise sequence similarity, represent a single novel species, for which the name Metschnikowia saccharicola sp. nov. is proposed. The type strain is DMKU-RK500(T) (= BCC 50735(T) = NBRC 108904(T) = CBS 12575(T)). Strain DMKU-RK277(T) was closest to Candida hainanensis but with 4.0 % nucleotide substitutions (18 nucleotide substitutions and three gaps out of 449 nt) in the D1/D2 domain of the LSU rRNA gene was assigned to be Metschnikowia lopburiensis sp. nov. (type strain DMKU-RK277(T) = BCC 50731(T) = NBRC 108902(T) = CBS 12574(T)).

Wickerhamomyces xylosica sp. nov. and Candida phayaonensis sp. nov., two xylose-assimilating yeast species from soil.

Two strains (NT29(T) and NT31(T)) of xylose-assimilating yeasts were obtained from soils collected in northern Thailand. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal transcribed spacer region, the two strains were found to represent two novel ascomycete yeast species. Strain NT29(T) was assigned to the genus Candida belonging to the Pichia clade as a representative of Candida phayaonensis sp. nov.; the type strain is NT29(T) (=BCC 47634(T)=NBRC 108868(T)=CBS 12319(T)). Strain NT31(T) represented a novel Wickerhamomyces species, which was named Wickerhamomyces xylosica sp. nov.; the type strain is NT31(T) (=BCC 47635(T)=NBRC 108869(T)=CBS 12320(T)).

Candida sirachaensis sp. nov. and Candida sakaeoensis sp. nov. two anamorphic yeast species from phylloplane in Thailand.

Three strains (LM008(T), LM068 and LM078(T)), representing two novel yeast species were isolated from the phylloplane of three plant species by an enrichment technique. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal spacer region, the three strains were assigned as two novel Candida species. Strain LM008(T) was assigned to be Candida sirachaensis sp. nov. (type strain LM008(T) = BCC 47628(T) = NBRC 108605(T) CBS 12094(T)) in the Starmerella clade. Two strains (LM068 and LM078(T)) represent a single species in the Lodderomyces-Spathaspora clade for which the name Candida sakaeoensis sp. nov. is proposed with the type strain LM078(T) = BCC 47632(T) = NBRC 108895(T) = CBS 12318(T).

Candida wangnamkhiaoensis sp. nov., an anamorphic yeast species in the Hyphopichia clade isolated in Thailand.

Two strains representing a single novel yeast species were isolated from a flower of Calycoopteris floribunda Lame (SK170(T)) and insect frass (ST-122) collected in Thailand. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene and the internal transcribed spacer region, the two strains were assigned as a single novel Candida species in the Hyphopichia clade for which the name Candida wangnamkhiaoensis sp. nov. is proposed. The type strain is SK170(T)=BCC 39604(T)=NBRC 106724(T)=CBS 11695(T)).

Ogataea phyllophila sp. nov., Candida chumphonensis sp. nov. and Candida mattranensis sp. nov., three methylotrophic yeast species from phylloplane in Thailand.

Five strains (LN12, LN14(T), LN15(T), LN16 and LN17(T)) representing three novel methylotrophic yeast species were isolated from the external surface of plant leaves by three-consecutive enrichments. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and the phylogenetic analysis, the five strains were assigned to be one novel Ogataea species and two novel Candida species. Three strains (LN12, LN14(T) and LN16) represent a single novel species of the genus Ogataea, for which the name Ogataea phyllophila sp. nov. is proposed. The type strain is LN14(T) (= BCC 42666(T) = NBRC 107780(T) = CBS 12095(T)). Strain LN15(T) was assigned to be Candida chumphonensis sp. nov. (type strain LN15(T) = BCC 42667(T) = NBRC 107781(T) = CBS 12096(T)). Strain LN17(T) represented another novel species of Candida that was named Candida mattranensis sp. nov. (type strain LN17(T) = BCC 42668(T) = NBRC 107782(T) = CBS 12097(T)).

Candida uthaithanina sp. nov., an anamorphic yeast species in Nakaseomyces clade isolated in Thailand.

Three yeast stains were isolated from two unknown fruits (strains DD2-22-1(T) and SK44) and moss (strain ST-449) in Thailand. Analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene sequences of the three strains revealed that they belonged to the same species. In terms of pairwise sequence similarity, Candida cf. glabrata UWO(PS) 98-110.4 and Candida nivariensis were the closest undescribed and recognized taxa, but the levels of nucleotide substitutions were 1.7-1.9% and 2.0-2.2%, respectively. The levels of nucleotide substitutions were sufficient to justify the description of a separate species of Candida. In the phylogenetic tree based on the D1/D2 domain of the LSU rRNA gene the three strains were placed in a separate branch in the Nakaseomyces clade with C. cf. glabrata UWO(PS)98-110.4, C. nivariensis, Candida glabrata, Candida bracarensis, Candida kungkrabaensis and Nakaseomyces delphensis. Phenotypic characteristics of the three strains were similar which included proliferation by multilateral budding, absence of ascospores, arthrospores or ballistospores; negative for Diazonium blue B and urease tests. The major ubiquinone was Q-6. On the basis of the above findings, the three strains were assigned to a single novel species of Candida, for which the name Candida uthaithanina sp. nov is proposed. The type strain is DD2-22-1(T) (= BCC 29899(T) = NBRC 104876(T) = CBS 10932(T)).

Candida saraburiensis sp. nov. and Candida prachuapensis sp. nov., xylose-utilizing yeast species isolated in Thailand.

Four strains of two novel xylose-utilizing yeast species were obtained from samples collected in Thailand from decaying corncobs (strains KU-Xs13(T) and KU-Xs18), a decaying grass (KU-Xs20) and estuarine water from a mangrove forest (WB15(T)). On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and sequence analysis of the D1/D2 domain of the large subunit rRNA gene, the four strains were found to represent two novel species of the genus Candida in the Candida albicans/Lodderomyces elongisporus clade. Three strains (KU-Xs13(T), KU-Xs18 and KU-Xs20) were assigned as a single novel species, which was named Candida saraburiensis sp. nov. The type strain is KU-Xs13(T) (=CBS 11696(T)=NBRC 106721(T)=BCC 39601(T)). Strain WB15(T) represented another novel species of the genus Candida that was named Candida prachuapensis sp. nov. The type strain is WB15(T) (=CBS 11024(T)=NBRC 104881(T)=BCC 29904(T)).

Candida andamanensis sp. nov., Candida laemsonensis sp. nov. and Candida ranongensis sp. nov., anamorphic yeast species isolated from estuarine waters in a Thai mangrove forest.

Five strains (RV5(T), RV140, R31(T), RS17 and RS28(T)) representing three novel anamorphic ascomycetous yeast species were isolated by membrane filtration from estuarine waters collected from a mangrove forest in Laem Son National Park, Ranong Province, Thailand, on different occasions. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, sequence analysis of the D1/D2 domain of the large-subunit rRNA gene and the internal transcribed spacer region and phylogenetic analysis, three strains were found to represent two novel Candida species. Two strains (RV5(T) and RV140) represented a single novel species, for which the name Candida laemsonensis sp. nov. is proposed. The type strain is RV5(T) (=BCC 35154(T) =NBRC 105873(T) =CBS 11419(T)). Strain R31(T) was assigned to a novel species that was named Candida andamanensis sp. nov. (type strain R31(T) =BCC 25965(T) =NBRC 103862(T) =CBS 10859(T)). On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, sequence analysis of the D1/D2 domain of the large-subunit rRNA gene and phylogenetic analysis, strains RS17 and RS28(T) represented another novel species of Candida, for which the name Candida ranongensis sp. nov. is proposed. The type strain is RS28(T) (=BCC 25964(T) =NBRC 103861(T) =CBS 10861(T)).

Candida xylanilytica sp. nov., a xylan-degrading yeast species isolated from Thailand.

Xylan is a major component of hemicellulose, which constitutes about 40 % of plant biomass. Hydrolysis of xylan into simple sugars is one of the important steps in the conversion of lignocellulosic material to value-added products. During an investigation of cellulose- and xylan-degrading yeasts, two yeast strains that were able to use cellulose and xylan as sole carbon source were found to represent a phylogenetically distinct species in the Spathaspora clade. The closest species in terms of pairwise sequence similarity in the D1/D2 domain of the LSU rRNA gene was Candida subhashii. The novel species can be distinguished from the other species in the Spathaspora clade based on the ability to assimilate methanol and raffinose, growth in medium containing 60 % glucose, and growth at 42 °C. It ferments glucose but not other carbohydrates. The name Candida xylanilytica sp. nov. is proposed for this species. The type strain is KU-Xn11(T) ( = NBRC 106499(T)  = BCC 34694(T)  = CBS 11761(T)).

Candida asiatica sp. nov., an anamorphic ascomycetous yeast species isolated from natural samples from Thailand, Taiwan, and Japan.

Six yeast strains of a novel anamorphic yeast species were isolated from natural samples collected in Thailand (RV60(T) and LYSM9), Taiwan (SC5L04 and GE19S05), and Japan (JCM 11058 and JCM 11059). Analysis of the D1/D2 domain of the large subunit rRNA gene sequences revealed that the sequences of five strains (LYSM9, SC5L04, GE19S05, JCM 11058, and JCM 11059) were identical and differed from the sequence of strain RV60(T) by only one nucleotide substitution. The closest recognized species in terms of pairwise sequence similarity was Candida abiesophila, but the level of nucleotide substitution (14.2-14.3%) was sufficient to justify the description of a separate species. Phenotypic characteristics of the six strains were almost the same except for two strains from Japan, which showed the ability to ferment glucose and grew in the presence of 10% NaCl and 5% glucose while the others did not. The phenotypic characteristics of the six strains included proliferation by multilateral budding, absence of ascospores, arthrospores, and ballistospores, and negative Diazonium blue B and urease tests. The major ubiquinone was Q-7. On the basis of the above findings, the six strains were assigned to a single novel species of Candida, for which the name Candida asiatica sp. nov. is proposed. The type strain is RV60(T) (BCC 25966(T) = NBRC 103863(T) = CBS 10863(T)).

Candida chanthaburiensis sp. nov., Candida kungkrabaensis sp. nov. and Candida suratensis sp. nov., three novel yeast species from decaying plant materials submerged in water of mangrove forests.

In a taxonomic study of yeasts isolated from decaying plant materials submerged in water of mangrove forests in Thailand, three strains isolated from tree bark (EM33(T)), a fallen leaf (EM40(T)) and a detached branch (SM56(T)) were found to represent three novel yeast species. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, the sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene, and the phylogenetic analysis, the three strains were assigned as three novel Candida species. They were named as Candida chanthaburiensis sp. nov. (type strain EM33(T) = BCC 23057(T) = NBRC 102176(T) = CBS 10926(T)), Candida kungkrabaensis sp. nov. (type strain EM40(T) = BCC 23060(T) = NBRC 102179(T) = CBS 10927(T)), and Candida suratensis sp. nov. (type strain SM56(T) = BCC 25961(T) = NBRC 103858(T) = CBS 10928(T)).

Geotrichum siamensis sp. nov. and Geotrichum phurueaensis sp. nov., two asexual arthroconidial yeast species isolated in Thailand.

Two asexual arthroconidial yeast strains, TM3-44(T) and LYSM5(T), were isolated, respectively, from estuarine water in a mangrove forest and soil in a terrestrial forest in Thailand. Analysis of the D1/D2 domains of the large-subunit rRNA gene sequences revealed that strain TM3-44(T) differed from the closest species in terms of pairwise sequence similarity, Dipodascus albidus, by 11.7% nucleotide substitutions, while strain LYSM5(T) was closest to Galactomyces geotrichum with only 2.9% nucleotide substitutions. The phylogenetic tree further demonstrated that strain TM3-44(T) was at a distant position from the closest species, D. albidus, and other related species in the Dipodascus clade, while strain LYSM5(T) clustered with G. geotrichum, it closest relative in the Galactomyces clade. The phenotypic characteristics of the two strains were typical of the genus Geotrichum. On the basis of the above findings, strain TM3-44(T) was assigned as a novel species of Geotrichum, for which the name Geotrichum siamensis sp. nov. is proposed. The type strain is TM3-44(T) (BCC 29903(T)=NBRC 104880(T)=CBS 10929(T)). Strain LYSM5(T) represented another novel species of Geotrichum, which was named Geotrichum phurueaensis sp. nov. The type strain is LYSM5(T) (BCC 34756(T)=NBRC 105674(T)=CBS 11418(T)).

Three anamorphic yeast species Candida sanitii sp. nov., Candida sekii sp. nov. and Candida suwanaritii, three novel yeasts in the Saturnispora clade isolated in Thailand.

Nine strains of three novel anamorphic yeast species were obtained from samples collected in Thailand including six strains (RV96, RV152, R14, RS9, RS58 and EA1) obtained from estuarine waters collected from two mangrove forests, one strain (ST84) from insect frass and two strains (SR16 and UB13) from forest soils. On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics, and the sequence analysis of the D1/D2 domain of the large subunit rRNA gene, the nine strains were found to represent three novel Candida species in the Saturnispora clade. Five strains (RV96, RV152, R14, RS9 and RS58) were assigned as a single novel species, which was named Candida sanitii sp. nov. The type strain is RV152(T) (BCC 25967(T)=NBRC 103864(T)=CBS 10864(T)). Strain EA1 was named as Candida suwanaritii sp. nov. The type strain is EA1(T) (BCC 29900(T)=NBRC 104877(T)=CBS 11021(T)). Three strains (ST84, SR16 and UB13) represented another novel species, for which Candida sekii sp. nov. is proposed. The type strain is ST84(T) (BCC 8320(T)=NBRC 105671(T)=CBS 10931(T)).

Three new species of bipolar budding yeasts of the genus Hanseniaspora and its anamorph Kloeckera isolated in Thailand.

In the course of a survey of yeast biodiversity in the natural substrates in Thailand, eight strains were found to represent three hitherto undescribed species of Hanseniaspora/Kloeckera. They were isolated from insect frass, flower, lichen, rotted fruit and rotted wood. Based on the morphological and physiological characteristics, and sequences of D1/D2 domain, six strains represent a single species of the genus Hanseniaspora, described as Hanseniaspora thailandica sp. nov. (type BCC 14938(T)=NBRC 104216(T)=CBS 10841(T)), and another strain as Hanseniaspora singularis sp. nov. (type BCC 15001(T)=NBRC 104214(T)=CBS 10840(T)). A further strain, which belongs to Kloeckera and does not produce ascospores, is described as Kloeckera hatyaiensis sp. nov. (type BCC 14939(T)=NBRC 104215(T)=CBS 10842(T)). Strains belonging to H. thailandica sp. nov. differed by 17-19 nucleotide substitutions from Hanseniaspora meyeri, the closest species. DNA reassociation between the two taxa showed 30-48% relatedness. Kloeckera hatyaiensis sp. nov. and H. singularis sp. nov. differed by eight and 16 nucleotide substitutions with one gap from the nearest species, Hanseniaspora clermontiae and Hanseniaspora valbyensis, respectively.