Chemistry: molecular biology and microbiology – Micro-organism – per se ; compositions thereof; proces of... – Fungi
Reexamination Certificate
2000-05-30
2001-04-10
Prats, Francisco (Department: 1651)
Chemistry: molecular biology and microbiology
Micro-organism, per se ; compositions thereof; proces of...
Fungi
C435S132000, C435S171000
Reexamination Certificate
active
06214605
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a novel microorganism and a process for producing polyol by use of the same and in particular to a new strain belonging to the genus Trichosporonoides, that is,
Trichosporonoides kounosuensis
7E-1 (FERM BP-6572), and a process for producing polyol by use of said strain.
BACKGROUND ART
As microorganisms having been practically used until now in producing polyol particularly erythritol, there are known two microorganisms i.e.
Moniliella tomentosa
var.
pollinis
CBS 461.67 and
Trichosporonoides megachiliensis
SN-G42 (FERM BP-1430) (which is the same as Aureobasidium sp. SN-G42 (FERM P-8940)). For the former, there are known a series of processes for producing polyol by fermentation of saccharides in industrial scale (Japanese Patent Publication Nos. 30591/1994, 30592/1994, 30593/1994 and 30594/1994). For the latter, there is known a novel microorganism having the ability to produce erythritol as well as a process for producing erythritol by fermentation with said microorganism (Japanese Patent Publication Nos. 11189/1992 and 635/1992).
For microorganisms of the genus Trichosporonoides, there is a report of Marina A. Y. Aoki in the State University of Campinas, Brazil, on conversion of glucose and sucrose into erythritol (Biotechnology Letters, Volume 15, No. 4, pp. 383-388, April 1993). According to this report, the rate of conversion of glucose into erythritol is as high as 43.0%, and the rate of conversion of sucrose into erythritol is as high as 37.4%, but the concentration of these saccharides in the culture medium is as low as 10% (W/V), so there is a problem with production in industrial scale.
Further, Ueda et al. in Mitsubishi Chemical Co., Ltd. reported that 5 strains of the genus Trichosporonoides, that is,
Trichosporonoides oedocephalis
CBS 649.66,
Trichosporonoides madida
CBS 240.79,
Trichosporonoides nigrescens
CBS 268.81,
Trichosporonoides spathulata
CBS 241.79, and
Trichosporonoides megachiliensis
CBS 567.85 can form erythritol from glucose (Japanese Patent Laid-Open No. 154589/1997). However, these microorganisms are not necessarily advantageous for large-scale production because the range of their culture temperatures is as narrow as 25 to 37° C. (suitable temperature of 27-35° C.) and a large amount of cooling water is required. Regrettably, it is known that
Trichosporonoides nigrescens
particularly exhibiting the best productivity of 136.0 g/L erythritol does not grow at 37° C. and at a concentration of 50% glucose (infra).
DISCLOSURE OF THE INVENTION
An object of the present invention is to provide a novel microorganism having a high ability to produce polyol, particularly a microorganism producing a large amount of polyol such as erythritol etc. even at relatively high temperatures (35 to 39° C.) and at high sugar levels (20 to 60%).
Another object of the present invention is to provide a process for producing polyol inexpensively by use of this microorganism.
The present inventor made extensive studies to find a novel microorganism having the ability to produce polyol particularly erythritol, and as a result, he found that a novel microorganism separated from a honeycomb solves the aforementioned problem, that is, this microorganism shows good growth at a culture temperature of 35 to 39° C. and at a sugar level of 20 to 60% to produce a large amount of polyol, and the present invention was thereby completed.
That is, the present invention relates to a novel microorganism belonging to the genus Trichosporonoides separated from a honeycomb and in particular to
Trichosporonoides kounosuensis
7E-1 (FERM BP-6572).
Further, the present invention relates to a process for producing polyol which comprises culturing said microorganism and recovering polyol which mainly contains erythritol, glycerin and ribitol from the culture.
BEST MODE FOR CARRYING OUT THE INVENTION
The novel microorganism of the present invention was separated in the following manner. That is, a honeycomb was cultivated in a medium containing 40% glucose whereby sugar-resistant microorganisms were selected, and the culture temperature was set at 35° C. whereby mesophilic or thermophilic microorganisms were selected. Then, the microorganism separated purely by a conventional microbial separation method was cultured in a medium containing 30% glucose, and measured for the amount of polyol accumulated in the culture, whereby a microorganism having a high ability to produce polyol, specifically
Trichosporonoides kounosuensis
7E-1, was separated.
This microorganism is internationally deposited as FERM BP-6572 (transferred on Nov. 12, 1998 from Japanese original deposit No. FERM P-16303, originally deposited on Jul. 3, 1997) with the Patent Microbial Deposit Center in the National Institute of Bioscience and Human-Technology, Agency of Industrial Science and Technology of 1-3, Higashi 1-chome, Tsukuba-shi, Ibaraki-ken, Japan.
The mycological properties of
Trichosporonoides kounosuensis
7E-1 isolated from a honeycomb in Kounosu-shi, Saitama-ken, Japan by the present inventor are described in detail as follows. The mycological properties of
Trichosporonoides kounosuensis
7E-1 were examined in accordance with “The Yeasts, A Taxonomic Study, Third Revised and Enlarged Edition”, edited by N. J. W. Kreger-van Rij Groningen, 1984, published by Elsevier Science Publishers B. V., Amsterdam.
1. The states of growth in medium
1) Microscopical observation
(Culture in YM broth at 25° C. for 3 days)
Size of vegetative cell: 4 to 7.5×4 to 12&mgr;
Shape of vegetative cell: spherical, egg-shaped or oval-shaped
State of vegetative cell: multipolar budding
(Slide culture on potato glucose agar at 25° C. for 7 days)
Blastic conidia: formed
Arthrospores: formed
Pseudomycelia: formed
Hypha: formed
2) Culture in liquid medium (Culture in YM broth at 25° C.)
Growth on the surface: film formation
Turbidity: transparent or slightly turbid
Sedimentation: high
Color of the medium: The medium turns pale brown after about 4-day culture and this color becomes darker, thereafter as the culture proceeds.
3) Agar (Culture on YM agar at 25° C. for 2 weeks)
Growth: good
Glossy: absent
Pigment: The colonies, as well as the medium, after culture for 1 week or more turn dark brown.
2. Formation of ascospores
Ascospores are not formed on potato glucose agar, corn meal agar, YM agar, Gorodkowa agar, and acetate medium.
3. Physiological properties
requirement for oxygen
aerobic
growth temperature
42° C.
optimum growth temperature
31 to 37° C.
pH for growth
2 to 10.5
optimum pH for growth
5 to 8
assimilation of KNO
3
positive
splitting of fat
negative
decomposition of urea
positive
liquefaction of gelatin
positive
formation of carotenoid
negative
formation of organic acids
positive
formation of esters
positive
formation of starch-like substance
negative
requirement for vitamin
positive
color reaction with diazonium blue B
positive
resistance to osmotic pressure
10% sodium chloride
positive (growing)
12% sodium chloride
negative (not growing)
60% glucose
positive (growing)
4. Fermentability of saccharides
glucose
positive
lactose
negative
galactose
positive
melibiose
negative
raffinose
negative
sucrose
positive
maltose
positive
inulin
negative
inositol
negative
5. Assimilation of carbon compounds
D-arabinose
−
L-arabinose
+
D-ribose
+
D-xylose
+
D-glucose
+
D-mannose
+
D-galactose
+
L-rhamnose
−
D-fructose
+
L-sorbose
−
maltose
+
sucrose
+
lactose
−
melibiose
−
cellobiose
+
trehalose
−
raffinose
−
melezitose
−
&agr;-methyl-D-glucoside
−
arbtin
+
esculin
−
salicin
−
dextrin
+
soluble starch
+
inulin
+
methanol
−
ethanol
+
adonitol (ribitol)
−
inositol
−
erythritol
+
D-mannitol
+
D-sorbitol
−
dulcitol
−
xylitol
+
glycerin
+
DL-lactate
−
succinate
+
citrate
+
The properties of the present strain are similar to those of the genus Trichosporon in view of yeast classif
Coe Susan D.
Frishauf, Holtz Goodman, Langer & Chick, P.C.
Nikken Chemicals Co., Ltd.
Prats Francisco
LandOfFree
Microorganism and a process for producing polyols by using... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Microorganism and a process for producing polyols by using..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Microorganism and a process for producing polyols by using... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2534545