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1.
The medicinal mushroom Inonotus obliquus has been a folk remedy for a long time in East-European and Asian countries. It is currently ascribed to a number of phenolic compounds as well as triterpenoids and polysaccharides responsible for significant biological and pharmacological properties. A study was conducted to determine the effects of inclusion of lignocellulosic material, in this case corn stover on production and antioxidant activity of extracellular (EPC) and intracellular phenolic compounds (IPC) by Inonotus obliquus in submerged fermentation. The corn stover medium contained 3% ground corn stover and 3.5% corn flour but the control medium contained 5% corn flour without corn stover. All of the other components were same in the two media. Decomposition rates of cellulose, hemicellulose, and lignin in the corn stover substrate were 20.9%, 17.9%, and 19.8% through 288 h of submerged cultivation. Lignocellulose decomposition in the corn stover-containing medium yielded significantly higher EPC (118.9/135.7 mg GAE (gallic acid equivalents)) and IPC (21.2/23.7 mg GAE) than in the control medium (34.7/42.5 mg GAE of EPC and 12.5/13.5 mg GAE of IPC) per liter of culture broth (EPC) and per gram of mycelia (IPC) in shake flask cultures/10 L fermenter runs. Both EPC and IPC from the corn stover medium showed a higher scavenging activity against hydroxyl radicals and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals than those from the control medium during the later fermentation period. In dose-dependent experiments, EPC from the corn stover medium at 216 h demonstrated a significantly stronger free radical scavenger activity against DPPH and hydroxyl radicals, shown as much lower IC50 values, than that from the control medium and IPC from the two media. 相似文献
2.
The effect of lignocellulose degradation in wheat straw, rice straw, and sugarcane bagasse on the accumulation and antioxidant activity of extra- (EPS) and intracellular polysaccharides (IPS) of Inonotus obliquus under submerged fermentation were first evaluated. The wheat straw, rice straw, and sugarcane bagasse increased the EPS accumulation by 91.4, 78.6, and 74.3 % compared with control, respectively. The EPS and IPS extracts from the three lignocellulose media had significantly higher hydroxyl radical- and 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity than those from the control medium. Of the three materials, wheat straw was the most effective lignocellulose in enhancing the mycelia growth, accumulation and antioxidant activity of I. obliquus polysaccharides (PS). The carbohydrate and protein content, as well as the monosaccharide compositions of the EPS and IPS extracts, were correlated with sugar compositions and dynamic contents during fermentation of individual lignocellulosic materials. The enhanced accumulation of bioactive PS of cultured I. obliquus supplemented with rice straw, wheat straw, and bagasse was evident. 相似文献
3.
Weifa Zheng Yanxia Zhao Xin Zheng Yubing Liu Shenyuan Pan Yucheng Dai Fuming Liu 《Applied microbiology and biotechnology》2011,89(1):157-167
While Inonotus obliquus produces a diverse range of bioactive metabolites in its natural habitats, it accumulates less in its submerged cultures.
We show here that coculture of I. obliquus with Phellinus punctatus resulted in less production of mycelial biomass but an increased accumulation of phenolic compounds, melanins, and lanostane-type
triterpenoids. Metabolites increased in production by coculture include phelligridin C, phelligridin H, methyl inoscavin A,
inoscavin C, inoscavin B, davallialactone, methyl davallialactone, foscoparianol D, 21,24-cyclopentalanosta-3β,21,25-triol-8-en,
lanosta-7,9(11),23-triene-3β,22,25-triol, and inotodisaccharide and melanins. Metabolites from coculture also showed an increased
potential for scavenging free radicals and inhibiting the proliferation of HeLa 229 cells. Davallialactone, methyl davallialactone,
and minor phenolic components are the major contributors for scavenging DPPH and hydroxyl radical in monoculture, and phelligridin
C, phelligridin H, methyl inoscavin A, inoscavin C, methyl davallialactone, foscoparianol D, and inotodisaccharide are those
for scavenging the tested radicals in coculture. Lanostane-type triterpenoids indicated limited roles in scavenging free radicals.
Nearly all the detected metabolites correlate positively with inhibiting proliferation of HeLa 229 cells. Thus, coculture
of I. obliquus with other fungi seems to be a cost-effective strategy for upregulating biosynthesis of bioactive metabolites. 相似文献
4.
A chemically defined medium for mycelial growth and exopolysaccharide (EPS) production by submerged culture of Phellinus igniarius was investigated. The mainly defined medium compositions were optimized by using orthogonal matrix method. The optimal defined
medium (per liter) was 40.0 g glucose, 4.0 g. glutamic acid, 4.0 g (NH4)2SO4, and initial pH 6.0. Under the optimal medium, the maximal mycelial biomass and EPS production were 12.33 ± 0.89 and 1.21 ± 0.08 g l−1 at 192 h in shake flask, while the maximal mycelial biomass and EPS production reached 13.86 ± 0.52 and 1.92 ± 0.07 g l−1 at 168 h in 3 l fermenter, respectively. The molecular weights (g mol−1) of four fractions isolated from EPS by gel permeation were about 6.4 × 106, 3.3 × 105, 2.7 × 105 and 2.9 × 103. This study should be widely applied to other secondary metabolites production from higher fungus in a chemically defined
medium and quantitative regulation of the metabolic flux in polysaccharide biosynthesis. 相似文献
5.
桦褐孔菌提取物抗氧化活性研究 总被引:3,自引:0,他引:3
以乙酸乙酯和甲醇为提取剂,采用索氏提取法,剩余残渣采用热水浸提,最终得到桦褐孔菌不同极性提取物,对其DPPH自由基、羟基自由基及超氧阴离子自由基清除活性作用进行了研究,确定桦褐孔菌的抗氧化能力,为深入研究和开发桦褐孔菌功能性食品奠定理论基础。实验结果表明桦褐孔菌具有较好的抗氧化活性,其中乙酸乙酯提取物的DPPH自由基清除率、羟基自由基清除率和超氧阴离子自由基清除率均高于其他两组分及BHT,桦褐孔菌提取物有望成为功能性食品组分中合成抗氧化剂的天然替代品。 相似文献
6.
A process at various pH values ranging from 4.5 to 7.5 for production of mycelia and extracellular polysaccharide (EPS) by
P. linteus fermentation in pH-controlled shaken bioreactor was investigated. A two-stage pH control strategy in which pH value was kept
at 6.5 for the first 24 h, and then switched to 4.5 was developed successfully to enhance simultaneously the cell growth and
EPS production. The maximum cell density and EPS production reached 15.13 ± 0.1 g/l on day 6 and 6.74 ± 0.1 g/l on day 4,
respectively. The anti- hyperlipemia effect of EPS and intracellular polysaccharide (IPS) extracted from mycelia were observed
that both EPS and IPS can obviously reduce the serum triglyceride (TG), the blood cholesterol (TC) and serum low density lipoprotein
(LDL) level, and increase the high density lipoprotein (HDL) level of the hyperlipemia mice. Polysaccharides from submerged
cultivation of medicinal fungus P. linteus have favorable potency to develop anti-hyperlipermia drugs. 相似文献
7.
Eliza Malinowska Wojciech Krzyczkowski Grzegorz Łapienis Franciszek Herold 《Journal of industrial microbiology & biotechnology》2009,36(12):1513-1527
The aim of this study was to optimize the culture medium used for the mycelial growth and production of intracellular polysaccharides
(IPS) and exopolysaccharides (EPS) in a submerged culture of Hericium erinaceum. Of the various factors examined, including carbon and nitrogen sources, vitamins, mineral elements, and initial pH, those
that proved to have a significant effect were then tested using a 24 central composite rotatable design (CCRD). Under the optimal culture conditions, the maximal yield of biomass reached 14.24 ± 0.45 g l−1 and was 1.85-fold higher than in the basal medium. The kinetics of EPS biosynthesis in a bioreactor showed that although
the highest yield of EPS (2.75 ± 0.27 g l−1) could be obtained on day 8, the process of biosynthesizing high molecular weight polysaccharides proceeded until the depletion
of the carbon source in the medium (after 14 days of cultivation). Our results could be very helpful in the large-scale production
of bioactive polysaccharides from H. erinaceum. 相似文献
8.
Jianguang Luo Jun Liu Chunling Ke Deliang Qiao Hong Ye Yi Sun Xiaoxiong Zeng 《Carbohydrate polymers》2009,78(3):409-415
Optimization of medium composition for the production of exopolysaccharides (EPS) from Phellinus baumii Pilát in submerged culture and the immuno-stimulating activity of EPS were carried out. Firstly, the medium components having significant effect on EPS production were screened out to be glucose, yeast extract and diammonium oxalate monohydrate by using a 2(7−3) fractional factorial design. Secondly, the concentrations of the three factors were optimized using central composite design in response surface methodology. As results, a quadratic model was found to fit for EPS production, and the optimal medium composition was determined as following (g/l): 34.12 glucose, 4 peptone, 5.01 yeast extract, 0.88 diammonium oxalate monohydrate, 0.75 MgSO4 and 1 KH2PO4 and 0.0075 thiamine (VB1). A yield of 2.363 ± 0.04 g/l for EPS was observed in verification experiment. Finally, EPS from P. baumii Pilát was found to have direct immuno-stimulating activity in vitro on splenocyte proliferative response and acid phosphatase activity in peritoneal macrophages in a dose-dependent manner. 相似文献
9.
Chu-Ting Liu I-Ting Hsu Cheng-Chun Chou Pei-Ren Lo Roch-Chui Yu 《World journal of microbiology & biotechnology》2009,25(5):883-890
In the present study, the production of exopolysaccharides (EPS) by 13 strains of Lactobacillus and 6 strains of Bifidobacterium in a chemical defined medium (CDM) supplemented with 30 g lactose/l was first compared. The highest EPS production of the
Lactobacillus strains was found in L. salivarius BCRC 14759 while among the Bifidobacterium strains examined, B. bifidum BCRC 14615 showed the highest EPS production. Analyzes of the effect of lactose concentration and cultivation temperature
on EPS production revealed that L. salivarius produced the highest amount of EPS (45.3 mg/l) in CDM supplemented with 5 g lactose/l at 40°C while B. bifidum produced the highest EPS (17.0 mg/l) in CDM supplemented with 40 g lactose/l at 35°C. α-Phosphoglucomutase, UDP-glucose pyrophosphorylase
and UDP-galactose-4-epimerase exhibited a markedly notable activity compared with other enzymes examined in the cell extract
of both test organisms. This indicates their possible involvement in the biosynthesis of EPS. 相似文献
10.
Honggui Wan Jianfeng Yuan Xianyang Shan Qiyang Wu Nan Shi 《Biotechnology and Bioprocess Engineering》2011,16(4):761-768
A gray and low viscosity extracellular polysaccharide (EPS) composed of N-acetylglucosamine, xylose, and mannose was isolated
from culture medium of Bacillus sp. strain LBP32 by ethanol precipitation followed by dialysis and freeze-drying. The crude biopolymer showed an apparent
molecular weight (Mw) of ∼ 9.62 × 104. Chemical and spectroscopic studies revealed that the bacterial biopolymer was composed of a β-1,4-linked backbone carrying
a low content of β-1,3-linked backbone. In addition, the EPS demonstrated a high antioxidant activity in a concentration dependent
manner. The 50% inhibition concentration (IC50) for quenching hydroxyl radical (·OH) and superoxide radical (·O2
−) were 0.042 and 0.165 mg/mL, respectively. Furthermore, the EPS demonstrated a strong protective effect against lipid peroxidation
and radiation such as UV radiation and ion beam irradiation. These results indicate that the protective effects of the EPS
were most likely due to its free radical scavenging ability. 相似文献
11.
Effects of phytohormones including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and 1-naphthalentacetic acid (NAA)
on mycelial growth of medicinal mushroom Phellinus linteus were investigated. Under the optimal IAA, IBA and NAA concentration of 1.0, 1.5 and 5.0 mg/l, the maximal mycelial diameter
reached 8.6 ± 0.4, 7.3 ± 2.6 and 9.0 ± 1.0 mm, respectively. The mycelial biomass and exopolysaccharide (EPS) production with
addition of 5.0 mg/l NAA in a shake flask were 6.24 ± 0.18 g/l at 168 h and 0.86 ±0.01 g/l at 192 h, which were enhanced by
15.98 and 56.36% compared to the control, respectively. However, the molecular weight and infrared spectrum of EPS were coincident
with the control. Results indicated that NAA at the proper concentration was beneficial in stimulating mycelial growth and
EPS biosynthesis, whereas it could not alter the molecular structure of EPS.
An erratum to this article can be found at 相似文献
12.
Nereida Mello Rosa da Gioppo Fabiana G. Moreira-Gasparin Andréa M. Costa Ana Maria Alexandrino Cristina Giatti Marques de Souza Rosane M. Peralta 《Journal of industrial microbiology & biotechnology》2009,36(5):705-711
Myrothecium verrucaria is a nondermatophytic filamentous fungus able to grow and to produce keratinase in submerged (93.0 ± 19 U/ml) and solid state
(98.8 ± 7.9 U/ml) cultures in which poultry feather powder (PFP) is the only substrate. The purpose of the present work was
to verify how different carbon and nitrogen sources can influence the production of keratinase by this fungus. Addition of carbohydrates, such as glucose and sucrose, caused only slight improvements in keratinase production, but the
addition of starch caused a significant improvement (135.0 ± 25 U/ml). The highest levels of keratinase activity, however,
were obtained by supplementing the PFP cultures with cassava bagasse, 168.0 ± 28 U/ml and 189.0 ± 26 U/ml in submerged and
solid state cultures, respectively. Contrarily, the supplementation of PFP medium with organic or inorganic nitrogen sources,
such as casein, soy bean protein, gelatin, ammonium nitrate and alanine, decreased the production of keratinase in both types
of cultures (around 20 U/ml), showing that the production of keratinase by M. verrucaria is repressed by nitrogen sources. The results obtained in this work suggest that the association of the two residues PFP
plus cassava bagasse could be an excellent option as a cheap culture medium for the production of keratinase in submerged
and solid state cultures. 相似文献
13.
Aims: To study the optimization of submerged culture conditions for exopolysaccharide (EPS) production by Armillaria mellea in shake‐flask cultures and also to evaluate the performance of an optimized culture medium in a 5‐l stirred tank fermenter. Methods and Results: Shake flask cultures for EPS optimal nutritional production contained having the following composition (in g l?1): glucose 40, yeast extract 3, KH2PO4 4 and MgSO4 2 at an optimal temperature of 22°C and an initial of pH 4·0. The optimal culture medium was then cultivated in a 5‐l stirred tank fermenter at 1 vvm (volume of aeration per volume of bioreactor per min) aeration rate, 150 rev min?1 agitation speed, controlled pH 4·0 and 22°C. In the optimal culture medium, the maximum EPS production in a 5‐l stirred tank fermenter was 588 mg l?1, c. twice as great as that in the basal medium. The maximum productivity for EPS (Qp) and product yield (YP/S) were 42·02 mg l?1 d?1 and 26·89 mg g?1, respectively. Conclusions: The optimal culture conditions we proposed in this study enhanced the EPS production of A. mellea from submerged cultures. Significance and Impact of the Study: The optimal culturing conditions we have found will be a suitable starting point for a scale‐up of the fermentation process, helping to develop the production of related medicines and health foods from A. mellea. 相似文献
14.
粗毛纤孔菌胞外多糖是粗毛纤孔菌液体发酵的重要活性代谢产物,但采用常规的发酵方法,粗毛纤孔菌胞外多糖的产量较低。为更好地获取粗毛纤孔菌胞外多糖,本文采用双向液体发酵的方法,通过向发酵培养基中添加适量的扁桃斑鸠菊叶粉末,来提高粗毛纤孔菌胞外多糖的产量,并对优化得到的胞外多糖抗氧化活性进行了研究。以发酵液中胞外多糖含量为指标,采用单因素实验和正交实验优化发酵条件;采用红外光谱对胞外多糖的结构特征进行分析;通过测定胞外多糖对ABTS、DPPH和羟基自由基的清除率来了解其抗氧化活性。结果表明,最优发酵条件为:扁桃斑鸠菊叶粉末添加量0.5g/L、发酵时间10d、pH 6.5、接种量5.0mL,在此条件下,粗毛纤孔菌胞外多糖的产量达到(2.34±0.25)mg/mL,与未添加扁桃斑鸠菊叶的空白组相比,其胞外多糖产量提高了约216.22%;红外分析与抗氧化活性实验结果表明,添加扁桃斑鸠菊叶后的胞外多糖与未添加扁桃斑鸠菊叶的胞外多糖红外主要吸收峰一致,并且对ABTS、DPPH以及羟基自由基清除能力相近。本研究结果表明扁桃斑鸠菊叶能够有效地提高粗毛纤孔菌胞外多糖的产量,为其他珍稀食药用菌胞外多糖的高效生产提供了新思路。 相似文献
15.
Microbial exopolysaccharides (EPSs) are very important because they are used in biotechnological applications in different industrial areas. The aim of the study was to determine the best EPS producer Pleurotus sp., to optimize EPS production and to perform partial purification and characterization of the produced EPS. After the production conditions were optimized, the EPS was isolated and partially purified. EPS was characterized by HP-TLC, 1H-NMR, FT-IR, and TGA. Hydroxyl, superoxide, and DPPH radical scavenging activities of the EPS were also investigated spectrophotometrically. The best EPS producer and its incubation period in submerged fermentation were determined as Pleurotus sajor caju and on 5 days, respectively. Culture conditions to increase EPS production were optimized as follows (in per liter): 90 g of glucose, 10 g of yeast extract, 10 g of peptone, and 100 mM of Mg2+. The optimal initial pH, temperature, and an agitation rate of culture were determined as 5.0, 25 °C, and 150 rate min−1, respectively. The highest EPS production was determined as 33.32 ± 1.6 g L−1. After isolation of EPS, one active fraction was obtained by gel filtration chromatography. EPS is composed mainly of glucose according to HP-TLC analysis. To the results, EPS had a complex structure by having carbohydrate and protein contents. The produced EPS had high degradation temperature as well as high antioxidant activity. 相似文献
16.
In vitro and in vivo antioxidant activity of exopolysaccharide fractions from Bifidobacterium animalis RH 总被引:1,自引:0,他引:1
The aim of the study was to purify the exopolysaccharides (EPS) produced from Bifidobacterium animalis RH, which was isolated from the feces of Bama centenarians in Guangxi of China, and evaluate their antioxidant activities in vitro and in vivo. 2 fractions, a neutral EPS fraction (EPSa) and an acidic EPS fraction (EPSb), were obtained and compared for antioxidative activity. In vitro, they both showed remarkable inhibition effect on lipid peroxidation and strong DPPH radical scavenging activity, hydroxyl radical scavenging activity, superoxide radical scavenging activity, in which the last two were measured by the electron spin resonance (ESR). In vivo, EPSa and EPSb were orally administrated for 30 days in a d-galactose induced aged mice model. As results, they both could significantly increase the activities of SOD, CAT and total antioxidant capacity (TAOC) in serums and glutathione GST in livers. They also could inhibit significantly the formation of MDA in serums and livers, and reduce the activity of MAO and lipofuscin accumulation in mice brain. Moreover, EPSb exhibited much higher antioxidant activities than EPSa in vitro and in vivo. The results suggested that EPS fractions of Bifidobacterium animalis RH had direct and potent antioxidant activities. 相似文献
17.
Response surface methodology (RSM) was applied to optimize the critical medium ingredients of Agaricus blazei. A three-level Box–Behnken factorial design was employed to determine the maximum biomass and extracellular polysaccharide
(EPS) yields at optimum levels for glucose, yeast extract (YE), and peptone. A mathematical model was then developed to show
the effect of each medium composition and its interactions on the production of mycelial biomass and EPS. The model predicted
the maximum biomass yield of 10.86 g/l that appeared at glucose, YE, peptone of 26.3, 6.84, and 6.62 g/l, respectively, while
a maximum EPS yield of 348.4 mg/l appeared at glucose, YE, peptone of 28.4, 4.96, 5.60 g/l, respectively. These predicted
values were also verified by validation experiments. The excellent correlation between predicted and measured values of each
model justifies the validity of both the response models. The results of bioreactor fermentation also show that the optimized
culture medium enhanced both biomass (13.91 ± 0.71 g/l) and EPS (363 ± 4.1 mg/l) production by Agaricus blazei in a large-scale fermentation process. 相似文献
18.
De Qin Xu Ming Liang Fu Qi He Chen Jing Liu 《Bioprocess and biosystems engineering》2011,34(1):103-111
This work aimed to develop the submerged cultivation conditions for improved exopolysaccharides (EPS) production by Armillaria luteo-virens Sacc. The effects of culture temperature, aeration rate, inoculum level, initial pH, and additives on EPS formation and mycelial
growth are investigated. The aeration rate, initial pH, and inoculum level significantly affected EPS production under the
submerged cultivation. The developed conditions were as follows: cultivation temperature 23 °C, initial pH 5.0, aeration rate
0.5 vvm, 0.5% Tween 80, inoculum level 5% (v/v), and shaking speed 120 r/min. Under the developed conditions, the highest
EPS production was 13.01 g/L at 5 days culture time. EPS production was examined in a 5 L bioreactor, and an unstructured
kinetic model for EPS formation was well developed. The verified investigations in the large-scale cultivation system showed
that the developed models are able to predict the submerged cultivation process of EPS formation. Current results revealed
that the submerged cultivation conditions can be utilized to control EPS production, and the unstructured models developed
are suitable for explaining EPS production by A. luteo-virens Sacc QH in a large-scale cultivation bioreactor. 相似文献
19.
Mycophenolic acid (MPA) is a fungal metabolite with a variety of biological activities and widely applied in clinical practices. We herein aimed to isolate a new Penicillium brevicompactum strain from the fruiting body of Inonotus obliquus to improve the production of MPA. The fruiting body of Inonotus obliquus was used to isolate P. brevicompactum strains. Identification of the P. brevicompactum strain was performed by sequencing and phylogenetic tree analysis. HPLC assay was conducted to identify the production of MPA. Submerged liquid fermentation and bi-directional fermentation were applied to improve the yield of MPA. The candidates of the P. brevicompactum strain were isolated and screened from the fruiting body of Inonotus obliquus collected from Changbai mountains in China. Based on sequencing and phylogenetic tree analysis of 18S rDNA-ITS, the strain MC-4 was finally identified as P. brevicompactum. And HPLC assay indicated that the isolated P. brevicompactum strain could produce MPA in metabolic products. The optimized conditions of submerged liquid fermentation were as follows: 100 g/L Chinese yam in a liquid PDB medium, pH 6, fermentation temperature of 24 °C, shaker speed of 130 r/min, and fermentation time of 6 days. The maximum value of MPA production was 1.415 g/L after submerged liquid fermentation. Furthermore, the yield of MPA could be significantly increased to 1.537 g/L after bi-directional fermentation with the extractive from fructus Swietenia macrophylla (FSM). We demonstrated that a Penicillium brevicompactum strain isolated from the fruiting body of Inonotus obliquus can be used to improve the production of MPA by submerged liquid fermentation and bi-directional fermentation. This would provide a novel approach for more efficient and safer production of MPA. 相似文献
20.
Efficient conversion of hexose and pentose (glucose and xylose) by a single strain is a very important factor for the production
of industrially important metabolites using lignocellulose as the substrate. The kinetics of growth and polyol production
by Debaryomyces nepalensis NCYC 3413 was studied under single and mixed substrate conditions. In the presence of glucose, the strain produced ethanol
(35.8 ± 2.3 g/l), glycerol (9.0 ± 0.2 g/l), and arabitol (6.3 ± 0.2 g/l). In the presence of xylose, the strain produced xylitol
(38 ± 1.8 g/l) and glycerol (18 ± 1.0 g/l) as major metabolites. Diauxic growth was observed when the strain was grown with
different combinations of glucose/xylose, and glucose was the preferred substrate. The presence of glucose enhanced the conversion
of xylose to xylitol. By feeding a mixture of glucose at 100 g/l and xylose at 100 g/l, it was found that the strain produced
a maximum of 72 ± 3 g/l of xylitol. A study of important enzymes involved in the synthesis of xylitol (xylose reductase (XR)
and xylitol dehydrogenase (XDH)), glycerol (glycerol-3-phosphate dehydrogenase (G3PDH)) and ethanol (alcohol dehydrogenase
(ADH)) in cells grown in the presence of glucose and xylose revealed high specific activity of G3PDH and ADH in cells grown
in the presence of glucose, whereas high specific activity of XR, XDH, and G3PDH was observed in cells grown in the presence
of xylose. To our knowledge, this is the first study to elaborate the glucose and xylose metabolic pathway in this yeast strain. 相似文献