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1.
Fermentation processes using sanguinarine-producing fungi other than Macleaya cordata may be an alternative way to produce sanguinarine (SA), which is a quaternary benzo[c]phenanthridine alkaloid possessing antibacterial, anthelmintic, and anti-inflammatory properties. In this study, a SA-producing endophytic fungus strain BLH51 was isolated from the leaves of M. cordata grown in the Dabie Mountain, China. Strain BLH51 produced SA when grown in potato dextrose liquid medium. The amount of SA produced by this endophytic fungus was quantified to be 178 μg/L by HPLC, substantially lower than that produced by the host tissue. The fungal SA—which was analyzed by thin layer chromatography and high-performance liquid chromatography—was shown to be identical to authentic SA. Strain BLH51 was identified as Fusarium proliferatum based on the morphological characteristics and nuclear ribosomal DNA ITS sequence analysis. To the best of our knowledge, this is the first report concerning the isolation and identification of endophytic SA-producing fungi from the host plant, which further proved that endophytic fungi are valuable reservoirs of bioactive compounds. 相似文献
2.
本研究从曼地亚红豆杉(Taxus x media)树皮内表皮分离得到一株产紫杉醇的内生真菌Z58,通过高效液相色谱法、质谱法和核磁共振波谱法对其紫杉醇提取物进行了分析. 结果表明,内生真菌Z58的紫杉醇提取物具有和紫杉醇标准品相近的色谱特征峰,其保留时间为10.2 min;也与紫杉醇标准品具有相同的质谱特征峰((M+Na)+=876)和1H-NMR谱带.并通过形态学特征分析和18S rDNA序列分析,将内生真菌Z58初步鉴定为肉座菌属(Hypocrea sp.)真菌.肉座菌Z58的紫杉醇产量约为2.5~3.0 μg/g(紫杉醇/菌丝干重),是一株具有潜在应用价值的产紫杉醇内生真菌. 相似文献
3.
Naoyuki Moriya Yukiko Moriya Hideo Nomura Kisato Kusano Yukoh Asada Hirofumi Uchiyama Enoch Y. Park Mitsuyasu Okabe 《Biotechnology and Bioprocess Engineering》2013,18(6):1083-1089
β-(1→3)-D-glucans with β-(1→6)-glycosidic linked branches are known to be immune activation agents and are incorporated in anti-cancer drugs and health-promoting supplements. β-Glucan concentration was 9.2 g/L in a 200-L pilot scale fermentor using mutant strain Aureobasidium pullulans M-2 from an imperfect fungal strain belonging to A. pullulans M-1. The culture broth of A. pullulans M-2 had a faint yellow color, whereas that of the wild-type had an intense dark green color caused by the accumulation of melanin-like pigments. β-Glucan produced by A. pullulans M-2 was identified as a polysaccharide of D-glucose monomers linked by β-(1→3, 1→6)-glycosidic bonds through GC/MS and NMR analysis. When a conventional medium was used in the culture of A. pullulans M-2 in a 3-L jar fermentor, β-glucan concentration was 1.4-fold that produced by the wild-type. However, when a medium optimized by statistical experimental design was used with dissolved oxygen at 10%, the β-glucan concentration was 9.9 g/L with a yield of 0.52 (g β-glucan/g consumed sucrose), 2.9-fold that of the wild-type. This level of productivity was reproduced when the fermentation was scaled up 200-L. The industrial production of high β-glucan without melanin-like pigments is highly expected, as a health-promoting supplement or functional food. 相似文献
4.
虫草素是一种核苷类似物,具有多种药理作用。利用虫草素产生菌发酵的方式获得虫草素,可能是产生虫草素的一种新方法。为筛选能产虫草素的内生真菌,从中国传统的中药冬虫夏草子实体中共分离得到42株真菌,经PDB液体培养后,采用高效液相色谱(HPLC)鉴定其代谢产物。结果表明:菌株OS17的代谢产物中含有虫草素,且虫草素产量为40.16 mg/L。基于形态学特征和ITS序列分析,菌株OS17被鉴定为淡色生赤壳菌(Bionectria ochroleuca)。这是首次从冬虫夏草中分离得到能产虫草素的生赤壳属,表明了内生真菌具有产生多种生物活性物质的潜力。 相似文献
5.
Aims: To characterize and identify a novel Huperzine A (HupA)‐producing fungal strain Slf14 isolated from Huperzia serrata (Thunb. ex Murray) Trev. in China. Methods and Results: The isolation, identification and characterization of a novel endophytic fungus producing HupA specifically and consistently from the leaves of H. serrata were investigated. The fungus was identified as Shiraia sp. Slf14 by molecular and morphological methods. The HupA produced by this endophytic fungus was shown to be identical to authentic HupA analysed by thin layer chromatographic, High‐performance liquid chromatography (HPLC), LC‐MS, 1H NMR and acetylcholinesterase (AChE) inhibition activity in vitro. The amount of HupA produced by Shiraia sp. Slf14 was quantified to be 327·8 μg l?1 by HPLC, which was far higher than that of the reported endophytic fungi, Acremonium sp., Blastomyces sp. and Botrytis sp. Conclusions: The production of HupA by endophyte Shiraia sp. Slf14 is an enigmatic observation. It would be interesting to further study the HupA production and regulation by the cultured endophyte in H. serrata and in axenic cultures. Significance and Impact of the Study: Although the current accumulation of HupA by the endophyte is not very high, it could provide a promising alterative approach for large‐scale production of HupA. However, further strain improvement and the fermentation process optimization are required to result in the consistent and dependable production. 相似文献
6.
Ing-Lung Shih Jin-Yee Yu Chienyan Hsieh Jane-Yii Wu 《Biochemical Engineering Journal》2009,43(1):33-40
Agrobacterium sp. was studied for the production of curdlan by conventional one-factor-at-a-time technique and response surface methodology. Factors such as initial pH, urea concentration, sucrose concentration having the greatest influence on the curdlan production were identified. By using response surface methodology (RSM), the curdlan production by Agrobacterium sp. was increased significantly by 109%, from 2.4 g/L to 5.02 g/L when the strain was cultivated in the optimal medium developed by RSM as compared to conventional one-factor-at-a-time technique. The curdlan production rate of 0.84 g/(L h) was obtained when Agrobacterium sp. was cultivated in the optimal medium developed by RSM, which was the highest curdlan production rate reported to date. The infrared (IR) and NMR spectra, the thermogram of DSC and pattern of X-ray diffraction for the curdlan of the present study were almost identical to those of the authentic curdlan sample (from Alcaligenes faecalis; Sigma). The purified curdlan was a linear polysaccharide composed of exclusively β-(1,3)-glucosidic linkages with the molecular weight of 160,000 Da by GPC. The crystalline melting point (Tm), glass transition temperature (Tg) and X-ray diffraction of the sample indicated low crystallinity in the structure. 相似文献
7.
Perumal Suresh Govintharaj Varathraju Vellasamy Shanmugaiah Khalid S. Almaary Yahya B. Elbadawi Ayman Mubarak 《Saudi Journal of Biological Sciences》2021,28(4):2155-2167
We find out the antimicrobial potential of partially purified 2,4-diacetylphloroglucinol (DAPG) against Ralstonia solanacearum and fungal plant pathogens isolated from tomato rhizobacterium Pseudomonas fluorescens VSMKU3054. The present study is mainly focused on the control of wilt disease of tomato by our isolate VSMKU3054 and DAPG. The cell free culture filtrate of P. fluorescens VSMKU3054 was significantly arrested the growth of R. solanacearum and fungal pathogens such as Rhizoctonia solani, Sclerotium rolfsii, Macrophomina phaseolina and Fusarium oxysporum compared to control. The existence of DAPG from the crude metabolites of P. fluorescens VSMKU3054 was confirmed on TLC with Rf value 0.34, which is coincide with that of authentic phloroglucinol. The partially purified DAPG exhibited much higher activity against R. solanacearum at 30 µg/ml than the fungal plant pathogens compared to control. The antimicrobial partially purified compound was identified as DAPG by UV, FT-IR and GC–MS analysis. The percentage of live cells of R. solanacearum when supplemented with DAPG at 30 µg/ml, significantly controlled the living nature of R. solanacearum up to 68% compared to tetracycline and universal control observed under high content screening analysis. The selected isolate P. fluorescens VSMKU3054 and DAPG significantly controlled wilt disease of tomato up to 59.5% and 42.12% on 3rd and 7th days compared to positive and negative control by detached leaf assay. Further, in silico analysis revealed that high interaction of DAPG encoding protease with lectin which is associated with R. solanacearum. Based on our findings, we confirmed that P. fluorescens VSMKU3054 and DAPG could be used a potential bio inoculants for the management of bacterial wilt disease of tomato. 相似文献
8.
Thet Thet Mar Nakarin Suwannarach Saisamorn Lumyong 《World journal of microbiology & biotechnology》2012,28(12):3281-3291
Spore productivity in six entomopathogenic fungal strains isolated from insect cadavers at four locations in Chiang Mai province was evaluated in five cereal grains: white-rice, wheat, rye, corn and sorghum. According to sequence analysis of the internal transcribed spacer regions of these isolates, they were closely related to Beauveria bassiana (2 isolates), Metarhizium flavoviride (1 isolate), Metarhizium anisopliae (1 isolate), Paecilomyces lilacinus (1 isolate) and Isaria tenuipes (1 isolate). Among all fungal isolates, the maximum amount of spores (530.0?×?109 conidia/g) was yielded P. lilacinus CMUCDMT02 on sorghum grain followed by white-rice (399.3?×?109 conidia/g). Moreover, the highest number of spore in M. flavoviride was 102.8?×?109 conidia/g sorghum whereas white-rice yielded the greatest amount of spore for B. bassiana CMUCDMF03 (141.0?×?109 conidia/g) after 60?days incubation. The fungal growth rate was found highest in corn for all strains and rye showed the lowest with the exception of P. lilacinus CMUCDMT02 among the tested grains. Spore viability was over 80?% for all isolates that had been inoculated for 60?days. Fungal conidia suspension of P. lilacinus obtained highest virulence against Bactrocera spp. at a concentration of 1?×?106 spore/ml. The strains isolated, exhibited good production of conidia suggesting a promising strategy for the mass production of inoculum as biocontrol agents with low production cost. 相似文献
9.
Qiangming Liu Jiancai Qin Tianwei Li Erbao Liu Dejia Fan Wisdom Mawuli Edzesi Jianhai Liu Jianhua Jiang Xiaoli Liu Lianjie Xiao Linglong Liu Delin Hong 《PloS one》2015,10(6)
The efficiency of hybrid seed production can be improved by increasing the percentage of exserted stigma, which is closely related to the stigma length in rice. In the chromosome segment substitute line (CSSL) population derived from Nipponbare (recipient) and Kasalath (donor), a single CSSL (SSSL14) was found to show a longer stigma length than that of Nipponbare. The difference in stigma length between Nipponbare and SSSL14 was controlled by one locus (qSTL3). Using 7,917 individuals from the SSSL14/Nipponbare F2 population, the qSTL3 locus was delimited to a 19.8-kb region in the middle of the short arm of chromosome 3. Within the 19.8-kb chromosome region, three annotated genes (LOC_Os03g14850, LOC_Os03g14860 and LOC_Os03g14880) were found in the rice genome annotation database. According to gene sequence alignments in LOC_Os03g14850, a transition of G (Nipponbare) to A (Kasalath) was detected at the 474-bp site in CDS. The transition created a stop codon, leading to a deletion of 28 amino acids in the deduced peptide sequence in Kasalath. A T-DNA insertion mutant (05Z11CN28) of LOC_Os03g14850 showed a longer stigma length than that of wild type (Zhonghua 11), validating that LOC_Os03g14850 is the gene controlling stigma length. However, the Kasalath allele of LOC_Os03g14850 is unique because all of the alleles were the same as that of Nipponbare at the 474-bp site in the CDS of LOC_Os03g14850 among the investigated accessions with different stigma lengths. A gene-specific InDel marker LQ30 was developed for improving stigma length during rice hybrid breeding by marker-assisted selection. 相似文献
10.
11.
In order to research the relationship between endophytic fungus and active ingredients in medicinal Paeonia suffruticosa, a total of 57 fungal isolates were isolated from the roots, stems, leaves and buds of medicinal plant Paeonia ostii; mycelium was collected after these fungal isolates were fermented on PDA medium for a few days; then the mycelium products were extracted; their extracts were analyzed by gas chromatography–mass spectrometry. With this method, a strain endophytic fungi named J1-2 which can produce paeonol was screened. Paeonol produced by J1-2 was analyzed by using a high resolution mass spectrometer (HRMS) and nuclear magnetic resonance (NMR). The potential paeonol-procucing named J1-2 was identified Chaetomium based on morphological characteristics and ITS sequence analysis. The current research initially indicates that endophytic fungi can affect the potency of peony. At the same time it also indicates that the numerous endophytic fungi inside the medicinal Paeonia suffruticosa are precious resource for the pharmaceutical natural products that are originally from the Paeonia suffruticosa. 相似文献
12.
Sasidharan Nishanth Kumar Sreerag Ravikumar Sreekala Dileep Chandrasekaran Bala Nambisan Ruby John Anto 《PloS one》2014,9(8)
The rhabditid entomopathogenic nematode associated Bacillus cereus and the antifungal compounds produced by this bacterium were evaluated for their activity in reducing postharvest decay of peanut kernels caused by Aspergillus species in in vitro and in vivo tests. The results showed that B. cereus had a significant effect on biocontrol effectiveness in in vitro and in vivo conditions. The antifungal compounds produced by the B. cereus were purified using silica gel column chromatography and their structure was elucidated using extensive spectral analyses. The compounds were identified as diketopiperazines (DKPs) [cyclo-(L-Pro-Gly), cyclo(L-Tyr-L-Tyr), cyclo-(L-Phe-Gly) and cyclo(4-hydroxy-L-Pro-L-Trp)]. The antifungal activities of diketopiperazines were studied against five Aspergillus species and best MIC of 2 µg/ml was recorded against A. flavus by cyclo(4-hydroxy-L-Pro-L-Trp). To investigate the potential application of cyclo(4-hydroxy-L-Pro-L-Trp) to eliminate fungal spoilage in food and feed, peanut kernels was used as a food model system. White mycelia and dark/pale green spores of Aspergillus species were observed in the control peanut kernels after 2 days incubation. However the fungal growth was not observed in peanut kernels treated with cyclo(4-hydroxy-L-Pro-L-Trp). The cyclo(4-hydroxy-L-Pro-L-Trp) was nontoxic to two normal cell lines [fore skin (FS) normal fibroblast and African green monkey kidney (VERO)] up to 200 µg/ml in MTT assay. Thus the cyclo(4-hydroxy-L-Pro-L-Trp) identified in this study may be a promising alternative to chemical preservatives as a potential biopreservative agent which prevent fungal growth in food and feed. To the best of our knowledge, this is the first report demonstrating that the entomopathogenic nematode associated B. cereus and cyclo(4-hydroxy-L-Pro-L-Trp) could be used as a biocontrol agents against postharvest fungal disease caused by Aspergillus species. 相似文献
13.
Nithya Karmegham Shanmugaiah Vellasamy Balasubramanian Natesan Mahaveer P. Sharma Dunia A. Al Farraj Mohamed S. Elshikh 《Saudi Journal of Biological Sciences》2020,27(12):3313-3326
We have shown, the outcome of antifungal activity of phenazine derivatives which is produced by fluorescent pseudomonads (FPs) for the control of sheath blight of rice. A total of 50 fluorescent pseudomonads (FPs) were isolated from rice rhizosphere. Off which, 36 FPs exhibited antagonistic activity against Rhizoctonia solani, Macrophomina phaseolina, Fusarium oxysporum, Alternaria alternata and Sclerotium rolfsii up to 70–80% compared to control by dual culture method. BOX-PCR analyses of antagonistic isolates indicated that two phylogenetic group, where group I consisted of 28 isolates and eight isolates belongs to group II. Among 36 FPs, a total of 10 FPs revealed that the presence of phenazine derivatives on thin layer chromatography (TLC), which is coincided with that of authentic phenazine with Rf value 0.57. Similar to TLC analysis, antibiotic encoding gene phenazine-1-carboxamide (PCN) was detected in 10 FPs by PCR analysis with respective primer. Among, PCN detected isolates of FPs, a significant biocontrol potential possessing isolate designated as VSMKU1 and it was showed prominent antifungal activity against R. solani and other tested fungal pathogens. Hence, the isolate VSMKU1 was selected for further studies. The selected isolate VSMKU1 was identified as Pseudomonas aeruginosa by 16S rDNA sequence analysis. The antifungal metabolite phenazine like compound produced by VSMKU1 was confirmed by UV, FT-IR and HPLC analysis. The phenazine compound from VSMKU1 significantly arrest the growth of R. solani compared to carbendazim by well diffusion method. The detached leaf assay showed remarkable inhibition of lesion height 80 to 85% by the treatments of culture (VSMKU1), cell free culure filtrate and phenazine like compound compared to control and other treatments was observed in detached leaves of rice. These results emphasized that VSMKU1 isolate can be used as an alternative potential biocontrol agent against sheath blight of rice, instead of using commercial fungicide such as validamycin and carbendazim which cause environmental pollution and health hazards. 相似文献
14.
Recently, Mucor indicus was introduced as a promising ethanol producing microorganism for fermentation of lignocellulosic hydrolysates, showing a number of advantages over Saccharomyces cerevisiae. However, high nutrient requirement is the main drawback of the fungus in efficient ethanol production from lignocelluloses. In this study, application of fungal extract as a potential nutrient source replacing all required nutrients in fermentation of wheat straw by M. indicus was investigated. Wheat straw was pretreated with N-methylmorpholine-N-oxide (NMMO) at 120 °C for 1–5 h prior to enzymatic hydrolysis. Hydrolysis yield was improved at least by 6-fold for 3 h pretreated straw compared with that of untreated one. A fungal extract was produced by autolysis of M. indicus biomass, an unavoidable byproduct of fermentation. Maximum free amino nitrogen (2.04 g/L), phosphorus (1.50 g/L), and total nitrogen (4.47 g/L) as well as potassium, magnesium, and calcium in the fungal extract were obtained by autolysis of the biomass at 50 °C and pH 5.0. The fungal extract as a nutrient-rich supplement substituted yeast extract and all other required minerals in fermentation and enhanced the ethanol yield up to 92.1% of the theoretical yield. Besides, appreciate amounts of chitosan were produced as another valuable product of the autolysis. 相似文献
15.
Mold spoilage is the main cause of substantial economic loss in cereals and might also cause public health problems due to the production of mycotoxins. The aim of this study was to separate and purify and to identify antifungal compounds of bacterium associated with novel entomopathogenic nematode and check the antifungal property of identified compound in particular food model systems. The antifungal compound was purified using silica gel column chromatography, TLC and HPLC and its structure was elucidated using NMR (1H NMR, 13C NMR, 1H–1H COSY, 1H–13C HMBC), HRMS and Marfey's method. Based on the spectral data, the active compounds were identified as diketopiperazine [cyclo(l-Pro-d-Leu)]. The antifungal activity of cyclo(l-Pro-d-Leu) was studied by MIC and paper disk assay against Aspergillus flavus MTCC 277 and Aspergillus niger MTCC 282 and best MIC value of 8 μg/ml was recorded against A. flavus. Cyclo(l-Pro-d-Leu) strongly inhibit mycelia growth of fungus and thereby affecting aflatoxin production. To investigate the potential application of the cyclo(l-Pro-d-Leu) and to eliminate fungal spoilage in food and feed, soybean and peanut were used as models. White mycelia and dark/pale green spores of A. flavus were observed in the control soybeans after 2-day incubation. However the fungal growth was not observed in soybeans treated with cyclo(l-Pro-d-Leu). Almost the same result was observed for peanuts treated with cyclo(l-Pro-d-Leu) for A. niger. The cyclo(l-Pro-d-Leu) was nontoxic to two normal human cell lines (FS normal fibroblast and L231 lung epithelial) up to 200 μg/ml. Thus the diketopiperazine derivative identified in the study may be a promising alternative to chemical preservatives as a potential biopreservative which prevent fungal growth and mycotoxin formation in food and feed. 相似文献
16.
Milind Gajbhiye Shivaji Sathe Vikas Shinde Balu Kapadnis 《Indian journal of microbiology》2016,56(1):99-102
A new fungal pathogen was isolated from rotten pomegranates collected from the orchards of different parts of Maharashtra. The pathogen was morphologically identified as Chaetomella raphigera followed by sequencing of ITS and D1/D2 hypervariable region of LSU (28S) of rRNA gene. The pathogen produced pectinase, cellulase, xylanase and protease in liquid medium at a concentration of 71, 13.8, 54.3 and 7 U/ml respectively. Enzyme activity was also determined during pathogenesis in the tissues artificially infected by C. raphigera. Xylanase activity was maximum (25.1 U/g) followed by pectinase (19.2 U/g) and cellulase (1.5 U/g), whereas, protease activity was unnoticed. There was significant correlation (P < 0.05) between disease rating scale and pectinase, xylanase and cellulase activity in infected tissues. This indicates the simultaneous production of hydrolytic enzymes that aids in necrosis of fruit tissues. The elevated levels of these enzymes in infected tissues as compared with control suggest their possible role in pathogenesis. Thus, pectinase, cellulase and xylanase produced by C. raphigera acts as major virulence factors in the development of fruit rot in pomegranates. This is a first report of fungal fruit rot caused by C. raphigera in pomegranate. 相似文献
17.
Repeated Introduction of Genetically Modified Pseudomonas putida WCS358r without Intensified Effects on the Indigenous Microflora of Field-Grown Wheat 总被引:1,自引:0,他引:1
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M. Viebahn D. C. M. Glandorf T. W. M. Ouwens E. Smit P. Leeflang K. Wernars L. S. Thomashow L. C. van Loon P. A. H. M. Bakker 《Applied microbiology》2003,69(6):3110-3118
To investigate the impact of genetically modified, antibiotic-producing rhizobacteria on the indigenous microbial community, Pseudomonas putida WCS358r and two transgenic derivatives were introduced as a seed coating into the rhizosphere of wheat in two consecutive years (1999 and 2000) in the same field plots. The two genetically modified microorganisms (GMMs), WCS358r::phz and WCS358r::phl, constitutively produced phenazine-1-carboxylic acid (PCA) and 2,4-diacetylphloroglucinol (DAPG), respectively. The level of introduced bacteria in all treatments decreased from 107 CFU per g of roots soon after sowing to less than 102 CFU per g after harvest 132 days after sowing. The phz and phl genes remained stable in the chromosome of WCS358r. The amount of PCA produced in the wheat rhizosphere by WCS358r::phz was about 40 ng/g of roots after the first application in 1999. The DAPG-producing GMMs caused a transient shift in the indigenous bacterial and fungal microflora in 1999, as determined by amplified ribosomal DNA restriction analysis. However, after the second application of the GMMs in 2000, no shifts in the bacterial or fungal microflora were detected. To evaluate the importance of the effects induced by the GMMs, these effects were compared with those induced by crop rotation by planting wheat in 1999 followed by potatoes in 2000. No effect of rotation on the microbial community structure was detected. In 2000 all bacteria had a positive effect on plant growth, supposedly due to suppression of deleterious microorganisms. Our research suggests that the natural variability of microbial communities can surpass the effects of GMMs. 相似文献
18.
Jianjun Sun Fei Xia Langjun Cui Jian Liang Zhezhi Wang Yukun Wei 《Applied microbiology and biotechnology》2014,98(7):3143-3155
Salvia miltiorrhiza Bunge, a well-known medicinal plant, has more than 20 effective components. The aim of this study was to comprehensively investigate foliar fungal endophyte communities of S. miltiorrhiza and explore the inside relationship between host-specific fungal endophytes and effective components accumulation. Five plant samples were collected from four geological different provinces in China. Foliar fungal endophyte communities were determined by terminal restriction fragment length polymorphism (T-RFLP) of the ITS region. Effective components were analyzed with high-performance liquid chromatography. The results showed that S. miltiorrhiza foliage harbored a large diversity of fungal endophytes. Principal component analysis revealed similar T-RFLP profiles and the characteristics of the 24 effective components among the five samples, which could be clustered into three groups. In foliar T-RFLP profiles derived from the restriction digestion by CfoI, HaeIII, MspI, or TaqI, there were identical 45, 42, 38, and 34 terminal restriction fragments (T-RFs) from the five samples. We consider these T-RFs as host-specific fungal endophytes. Correlation analysis of these T-RFs’ area and 24 effective components contents revealed a significant correlationship between some host-specific fungal endophytes and foliage or root effective components accumulation. 相似文献
19.
Yangmin Gong Jiao Liu Mulan Jiang Zhuo Liang Hu Jin Xiaojia Hu Xia Wan Chuanjiong Hu 《PloS one》2015,10(5)
Rapeseed meal and waste molasses are two important agro-industrial by-products which are produced in large quantities. In this study, solid state fermentation and fungal autolysis were performed to produce rapeseed meal hydrolysate (RMH) using fungal strains of Aspergillus oryzae, Penicillium oxalicum and Neurospora crassa. The hydrolysate was used as fermentation feedstock for heterotrophic growth of microalga Crypthecodinium cohnii that produce docosahexaenoic acid (DHA). The addition of waste molasses as a supplementary carbon source greatly increased the biomass and DHA yield. In the batch fermentations using media composed of diluted RMH (7%) and 1-9% waste molasses, the highest biomass concentration and DHA yield reached 3.43 g/L and 8.72 mg/L, respectively. The algal biomass produced from RMH and molasses medium also had a high percentage of DHA (22-34%) in total fatty acids similar to that of commercial algal biomass. RMH was shown to be rich in nitrogen supply comparable to the commercial nitrogen feedstock like yeast extract. Using RMH as sole nitrogen source, waste molasses excelled other carbon sources and produced the highest concentration of biomass. This study suggests that DHA production of the marine dinoflagellate C. cohnii could be greatly improved by concomitantly using the cheap by-products rapeseed meal hydrolysate and molasses as alternative feedstock. 相似文献
20.
Human epidermal growth factor/urogastrone: Rapid purification procedure and partial characterization
A new procedure for the isolation of two biologically active forms of human epidermal growth factor (h-EGF-1) and (h-EGF-2) has been devised. Starting with 20 liters of raw human urine, the method employs a six-step fractionation procedure which yields 100–150 μg of h-EGF-1 and 50–100 μg of h-EGF-2. Initial studies suggest that h-EGF-2 may have been derived from h-EGF-1 by removal of the carboxy-terminal arginine or leucine-arginine residue(s). Based on immunological data and electrophoretic mobility at pH 9.5, h-EGF-2 appears to be identical to authentic h-EGF isolated by Cohen and Carpenter (Proc. Natl. Acad. Sci., 1975, 72, 1317). Using the antibody to authentic h-EGF, single precipitin lines of identity are observed between h-EGF-1, h-EGF-2, and authentic h-EGF. Both forms of h-EGF have comparable biological activity in stimulating the growth of adult human skin fibroblasts in culture. 相似文献