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1.
Polysaccharides and ganoderic acids (GAs) are the major bioactive constituents of Ganoderma species. However, the commercialization of their production was limited by low yield in the submerged culture of Ganoderma despite improvement made in recent years. In this work, twelve Ganoderma strains were screened to efficiently produce polysaccharides and GAs, and Ganoderma lucidum 5.26 (GL 5.26) that had been never reported in fermentation process was found to be most efficient among the tested stains. Then, the fermentation medium was optimized for GL 5.26 by statistical method. Firstly, glucose and yeast extract were found to be the optimum carbon source and nitrogen source according to the single-factor tests. Ferric sulfate was found to have significant effect on GL 5.26 biomass production according to the results of Plackett–Burman design. The concentrations of glucose, yeast extract and ferric sulfate were further optimized by response surface methodology. The optimum medium composition was 55 g/L of glucose, 14 g/L of yeast extract, 0.3 g/L of ferric acid, with other medium components unchanged. The optimized medium was testified in the 10-L bioreactor, and the production of biomass, IPS, total GAs and GA-T enhanced by 85, 27, 49 and 93 %, respectively, compared to the initial medium. The fermentation process was scaled up to 300-L bioreactor; it showed good IPS (3.6 g/L) and GAs (670 mg/L) production. The biomass was 23.9 g/L in 300-L bioreactor, which was the highest biomass production in pilot scale. According to this study, the strain GL 5.26 showed good fermentation property by optimizing the medium. It might be a candidate industrial strain by further process optimization and scale-up study.  相似文献   

2.
The purposes of this study were to assess the influence of culture medium on biomass production, fatty acid, and pigment composition of Choricystis minor var. minor and to evaluate the use of this microalga as a source of fatty raw material for biodiesel production. Cultures of C. minor var. minor were grown using WC (Wright’s cryptophyte) and BBM (Bold’s Basal medium) media. BBM medium produced more biomass (984.3 mg L?1) compared to the WC medium (525.7 mg L?1). Despite this result, WC medium produced a higher methyl ester yield for biodiesel production than the BBM medium (170.0 and 90.2 mg g?1 of biomass, respectively). The average percentage of fatty acids obtained using the WC medium (17.0 %) was similar to soybean (18.0 %) and with similar biomass fatty acid profile. However, for pigment production, carotenoids and chlorophyll concentrations were twice as high when using the BBM medium.  相似文献   

3.
The submerged cultivating conditions for triterpenoids production from Antrodia cinnamomea were optimized using uniform design method and the one-factor-at-a-time method was adopted to investigate the effect of plants oils and glucose supply on triterpenoids production and mycelia growth. Corn starch and culturing time were identified as more significant variables for triterpenoids production. The optimal conditions for triterpenoids production was 20.0 g/L corn starch, 20.0 g/L wheat bran, 1.85 g/L MgSO4, initial pH 3 and 16 days of cultivation. In addition, investigation of plant oils and glucose supply showed that 0.3 % (v/v) olive oil supply at the beginning of fermentation stimulated mycelia growth and significantly increased triterpenoids production; 0.2 % (w/v) glucose supplement at 10th day enhanced production of triterpenoids with slight effect on biomass, which is reported for the first time. The triterpenoids production experimentally obtained under the optimal conditions was 7.23 % (w/w). The uniform design method may be used to optimize many environmental and genetic factors such as temperature and agitation that can also affect the triterpenoids production from A. cinnamomea.  相似文献   

4.
A nitrile-hydrolysing bacterium, identified as Isoptericola variabilis RGT01, was isolated from industrial effluent through enrichment culture technique using acrylonitrile as the carbon source. Whole cells of this microorganism exhibited a broad range of nitrile-hydrolysing activity as they hydrolysed five aliphatic nitriles (acetonitrile, acrylonitrile, propionitrile, butyronitrile and valeronitrile), two aromatic nitriles (benzonitrile and m-Tolunitrile) and two arylacetonitriles (4-Methoxyphenyl acetonitrile and phenoxyacetonitrile). The nitrile-hydrolysing activity was inducible in nature and acetonitrile proved to be the most efficient inducer. Minimal salt medium supplemented with 50 mM acetonitrile, an incubation temperature of 30 °C with 2 % v/v inoculum, at 200 rpm and incubation of 48 h were found to be the optimal conditions for maximum production (2.64 ± 0.12 U/mg) of nitrile-hydrolysing activity. This activity was stable at 30 °C as it retained around 86 % activity after 4 h at this temperature, but was thermolabile with a half-life of 120 min and 45 min at 40 °C and 50 °C respectively.  相似文献   

5.
Integrative processes for the production of bioenergy and biopolymers are gaining importance in recent years as alternatives to fossil fuels and synthetic plastics. In the present study, Bacillus thuringiensis strain EGU45 has been used to generate hydrogen (H2), polyhydroxybutyrate (PHB) and new co-polymers (NP). Under batch culture conditions with 250 ml synthetic media, B. thuringiensis EGU45 produced up to 0.58 mol H2/mol of glucose. Effluent from the H2 production stage was incubated under shaking conditions leading to the production of PHB up to 95 mg/l along with NP of levulinic acid up to 190 mg/l. A twofold to fourfold enhancement in PHB and up to 1.5 fold increase in NP yields was observed on synthetic medium (mixture of M-9+GM-2 medium in 1:1 ratio) containing at 1–2 % glucose concentration. The novelty of this work lies in developing modified physiological conditions, which induce bacterial culture to produce NP.  相似文献   

6.
Ecobiotechnological approach is an attractive and economical strategy to enrich beneficial microbes on waste biomass for production of Polyhydroxyalkanoate (PHA). Here, six strains of Bacillus spp. were used to produce co-polymers of PHA from pea-shells. Of the 57 mixed bacterial cultures (BCs) screened, two of the BCs, designated as 5BC1 and 5BC2, each containing 5 strains could produce PHA co-polymer at the rate of 505–560 mg/l from feed consisting of pea-shell slurry (PSS, 2 % total solids) and 1 % glucose (w/v). Co-polymer production was enhanced from 65–560 mg/l on untreated PSS to 1,610–1,645 mg/l from PSS treated with defined hydrolytic bacteria and 1 % glucose. Supplementation of the PSS hydrolysate with sodium propionate enabled 5BC1 to produce co-polymer P(3HB-co-3HV) with a 3HV content up to 13 % and a concomitant 1.46-fold enhancement in PHA yield. Using the principles of ecobiotechnology, this is the first demonstration of PHA co-polymer production by defined co-cultures of Bacillus from biowaste as feed under non-axenic conditions.  相似文献   

7.
The “attached cultivation” method of microalgae in which the wet paste of algal biomass is attached onto supporting materials to form an immobilized biofilm layer, and the culture medium is supplied to this layer to provide nutrients and moisture for growth was highly efficient in biomass production and represents a promising technology to improve the biofuel industry. To optimize the nitrogen supply strategy for this attached cultivation method, the growth and total lipids accumulation properties for the green alga Aucutodesmus obliquus with this method were studied under different quantities of nitrogen source and different volumes of aqueous medium that continuously circulated inside the photobioreactor. Results showed that, compared with medium volume, the nitrogen quantity was a stronger factor affecting the growth and total lipid accumulation. An optimized nitrogen supply strategy for the attached cultivation of A. obliquus is proposed as circulating ca. 60 L of BG-11 medium containing 1/10 of nitrate concentration for 1 m2 of cultivation surface. With this strategy, the attached A. obliquus accumulated biomass and total lipids simultaneously and obtained a high triacylglyceride productivity of 2.53 g m?2 day?1 in 7 days under subsaturated illumination of 100 μmol photons m?2 s?1. The water usage of 60 L m?2 was potentially decreased to <2 L m?2 if the nutrient supply was further improved. Dissolving the nitrogen source in small volume was the best way to efficiently utilize the nitrogen source with minimum of waste.  相似文献   

8.
Arthrobacter sp. HPC1223 (Genebank Accession No. AY948280) isolated from activated biomass of effluent treatment plant was capable of utilizing 2,4,6 trinitrophenol (TNP) under aerobic condition at 30 °C and pH 7 as nitrogen source. It was observed that the isolated bacteria utilized TNP up to 70 % (1 mM) in R2A media with nitrite release. The culture growth media changed into orange-red color hydride-meisenheimer complex at 24 h as detected by HPLC. Oxygen uptake of Arthrobacter HPC1223 towards various nitro/amino substituted phenols such as dinitrophenol (1.2 nmol/min/mg cells), paranitrophenol (0.9 nmol/min/mg cells), 2-aminophenol (0.75 nmol/min/mg cells), p-aminophenol (0.4 nmol/min/mg cells), phenol (0.56 nmol/min/mg cells) and TNP (2.42 nmol/min/mg cell) was analysed, which showed its additional characteristic of broad substrate catabolic capacity. The present study thus report a novel indigenous bacteria isolated from activated sludge utilized TNP and has broad catabolic potential towards substituted phenols.  相似文献   

9.
Fast-growing hairy root cultures of Picrorhiza kurroa induced by Agrobacterium rhizogenes offers a potential production system for iridoid glycosides. In present study we have investigated the effects of various nutrient medium formulations viz B5, MS, WP and NN, and sucrose concentrations (1–8%) on the biomass and glycoside production of selected clone (14-P) of P. kurroa hairy root. Full strength B5 medium was found to be most suitable for maximum biomass yield on the 40th day of culture (GI = 32.72 ± 0.44) followed by the NN medium of the same strength (GI = 22.9 ± 0.43). Secondary metabolite production was 1.1 and 1.3 times higher in half strength B5 medium respectively in comparison to MS medium. Maximum biomass accumulation along with the maximum picroliv content was achieved with 4% sucrose concentration in basal medium. RT vitamin and Thiamine-HCl effected the growth and secondary metabolite production of hairy roots growing on MS medium but did not show any effect on other media. The pH of the medium played significant role in growth and secondary metabolite production and was found to be highest at pH 6.0 while lowest at pH 3.0 and pH 8.0. To enhance the production of biomass and Picroliv 5 liter working capacity bioreactor was used, 27-fold (324 g FW) higher growth was observed in bioreactor than shake flask and secondary metabolite production was similarly enhanced.  相似文献   

10.
Withania somnifera is an important medicinal plant that contains withanolides as bioactive compounds. We have investigated the effects of macroelements and nitrogen source in hairy roots of W. somnifera with the aim of optimizing the production of biomass and withanolide A content. The effects of the macroelements NH4NO3, KNO3, CaCl2, MgSO4 and KH2PO4 at concentrations of 0, 0.5, 1.0, 1.5 and 2.0× strengths and of nitrogen source [NH4 +/NO3 ? (0.00/18.80, 7.19/18.80, 14.38/18.80, 21.57/18.80, 28.75/18.80, 14.38/0.00, 14.38/9.40, 14.38/18.80, 14.38/28.20 and 14.38/37.60 mM)] in Murashige and Skoog medium were evaluated for biomass and withanolide A production. The highest accumulation of biomass (139.42 g l?1 FW and 13.11 g l?1 DW) was recorded in the medium with 2.0× concentration of KH2PO4, and the highest production of withanolide A was recorded with 2.0× KNO3 (15.27 mg g?1 DW). The NH4 +/NO3 ? ratio also influenced root growth and withanolide A production, with both parameters being larger when the NO3 ? concentration was higher than that of NH4 +. Maximum biomass growth (148.17 g l?1 FW and 14.79 g l?1 DW) was achieved at NH4 +/NO3 ? ratio of 14.38/37.60 mM, while withanolide A production was greatest (14.68 mg g?1 DW) when the NH4 +/NO3 ? ratio was 0.00/18.80 mM. The results are useful for the large scale cultivation of Withania hairy root culture for the production of withanolide A.  相似文献   

11.
Bioethanol production from lignocellulosic materials has several limitations. One aspect is the high production cost of cellulases used for saccharification of substrate and inhibition of fermenting yeast due to inhibitors released in acid hydrolysis. In the present work we have made an attempt to achieve simultaneous cellulases production, saccharification and detoxification using dilute acid hydrolysate of Saccharum spontaneum with and without addition of nutrients, supplemented with acid hydrolyzed biomass prior to inoculation in one set and after 3 days of inoculation in another set. Organisms used were T. reesei NCIM 992, and Aspergillus niger isolated in our laboratory. Cellulase yield obtained was 0.8 IU/ml on fourth day with T. reesei. Sugars were found to increase from fourth to fifth day, when hydrolysate was supplemented with nutrients and acid hydrolyzed biomass followed by inoculation with T. reesei. Phenolics were also found to decrease by 67%.  相似文献   

12.
An efficient hairy root induction system for an important endangered medicinal plant, Dracocephalum kotschyi, was developed through Agrobacterium rhizogenes-mediated transformation by modifying the co-cultivation medium using five bacterial strains, A4, ATCC15834, LBA9402, MSU440, and A13 (MAFF-02-10266). A drastic increase in transformation frequency was observed when a Murashige and Skoog medium lacking NH4NO3 KH2PO4, KNO3 and CaCl2 was used, resulting in hairy root induction frequencies of 52.3 %, 69.6 %, 48.6 %, 89.0 %, and 80.0 % by A4, A13, LBA9402, MSU440, and ATCC15834 strains, respectively. For shoot induction, hairy roots and unorganized tumors induced by strain ATCC15834 were placed on an MS media supplemented with 0.1, 0.25, 0.5, and 1 mg/l BA plus 0.1 mg/l NAA. The high frequency of shoot regeneration and number of shoot were obtained in the medium containing 0.25 mg/l BA and 0.1 mg/l NAA. Root induction occurred from the base of regenerated shoots on the MS medium supplemented with 0.5 mg/l IBA after 10 days.  相似文献   

13.
The effect of nitrogen source concentration on the production of the polysaccharide curdlan by the bacterium Agrobacterium sp. ATCC 31749 from hydrolysates of prairie cordgrass was examined. The highest curdlan concentrations were produced by ATCC 31749 when grown on a medium containing a solids-only hydrolysate and the nitrogen source ammonium phosphate (2.2 mM) or on a medium containing a complete hydrolysate and 3.3 mM ammonium phosphate. The latter medium sustained a higher level of bacterial curdlan production than the former medium after 144 hr. Biomass production by ATCC 31749 was highest after 144 hr when grown on a medium containing a solids-only hydrolysate and 2.2 or 8.7 mM ammonium phosphate. On the medium containing the complete hydrolysate, biomass production by ATCC 31749 was highest after 144 hr when 3.3 mM ammonium phosphate was present. Bacterial biomass production after 144 hr was greater on the complete hydrolysate medium compared to the solids-only hydrolysate medium. Curdlan yield produced by ATCC 31749 after 144 hr from the complete hydrolysate medium containing 3.3 mM ammonium phosphate was higher than from the solids-only hydrolysate medium containing 2.2 mM ammonium phosphate.  相似文献   

14.
The influence of Gracilaria edulis and Sargassum wightii extracts was investigated for the production of biomass and withanolides in the multiple shoot suspension culture of Withania somnifera. Supplementation of 40 % G. edulis extract in MS liquid medium for 24 h exposure time in the culture recorded the highest biomass accumulation [62.4 g fresh weight and 17.82 g dry weight (DW)] and withanolides production (withanolide A 0.76 mg/g DW; withanolide B 1.66 mg/g DW; withaferin A 2.80 mg/g DW and withanone 2.42 mg/g DW) after 5 weeks of culture, which were 1.45–1.58-fold higher than control culture. This naturally available G. edulis extract-treated multiple shoot suspension culture protocol offers a potential alternative for the optimum production of biomass and withanolides utilizing shake-flasks.  相似文献   

15.
Production of carotenoids by Rhodococcus opacus PD630 is reported. A modified mineral salt medium formulated with glycerol as an inexpensive carbon source was used for the fermentation. Ammonium acetate was the nitrogen source. A dry cell mass concentration of nearly 5.4 g/L could be produced in shake flasks with a carotenoid concentration of 0.54 mg/L. In batch culture in a 5 L bioreactor, without pH control, the maximum dry biomass concentration was ~30 % lower than in shake flasks and the carotenoids concentration was 0.09 mg/L. Both the biomass concentration and the carotenoids concentration could be raised using a fed-batch operation with a feed mixture of ammonium acetate and acetic acid. With this strategy, the final biomass concentration was 8.2 g/L and the carotenoids concentration was 0.20 mg/L in a 10-day fermentation. A control of pH proved to be unnecessary for maximizing the production of carotenoids in this fermentation.  相似文献   

16.
Gymnema sylvestre is an important medicinal plant that bears bioactive compound namely gymnemic acid. In the present study, G. sylvestre was transformed by Agrobacterium rhizogenes. Seedling explants namely roots, stems, hypocotyls, cotyledonary nodal segments, cotyledons and young leaves were inoculated with A. rhizogenes strain KCTC 2703. Transformed (hairy) roots were induced from cotyledons and leaf explants. Six transgenic clones of hairy roots were established and confirmed by polymerase chain reaction (PCR) and RT-PCR using rolC specific primers. Hairy roots cultured using MS liquid medium supplemented with 3 % sucrose showed highest accumulation of biomass (97.63 g l?1 FM and 10.92 g l?1 DM) at 25 days, whereas highest accumulation of gymnemic acid content (11.30 mg g?1 DM) was observed at 20 days. Nearly 9.4-fold increment of biomass was evident in suspension cultures at 25 days of culture and hairy root biomass produced in suspension cultures possessed 4.7-fold higher gymnemic acid content when compared with the untransformed control roots. MS-based liquid medium was superior for the growth of hairy roots and production of gymnemic acid compared with other culture media evaluated (B5, NN and N6), with MS-based liquid medium supplemented with 3 % sucrose was optimal for secondary metabolite production. The current results showed great potentiality of hairy root cultures for the production of gymnemic acid.  相似文献   

17.
Cuphea aequipetala Cav. (Lythraceae), a species highly valued for its medicinal properties, is threatened in the wild. To provide an alternative source of material for production of bioactive compounds, we established adventitious root cultures of C. aequipetala and determined their phenolic compounds contents and antioxidant activity. Cultures were initiated from root tips of in vitro C. aequipetala plantlets and were grown in B5 or SH culture medium containing either indole butyric acid (IBA) or α-naphthalene acetic acid at 0, 5 or 10 µM. The maximum root biomass (1.6 g/L dry mass (DM) per L medium) was recorded after 14 days of growth in B5 + 5 µM IBA. Roots in B5 medium remained green, whereas they tended to oxidize in SH medium. The highest contents of total phenolic compounds (9.1 ± 0.1 µg gallic acid equivalents/g DM) and flavonoids (37.5 ± 0.7 µg quercetin equivalents/g DM) were in roots grown in B5 + 5 µM IBA after 14 days of growth. Root cultures accumulated mainly flavan-3-ols, whereas roots or leaves from whole plants accumulated mainly flavonols. We analyzed the antioxidant properties of root extracts using in vitro assays. Roots grown in B5 medium showed stronger free-radical scavenging activity than that of roots grown in SH medium. Our results show that adventitious root cultures of C. aequipetala are a promising system for research on antioxidant compounds biosynthesis and for scaled-up production of useful biological materials.  相似文献   

18.
This study was focused on a comparison of growth and production properties of seven red yeast strains of the genus Rhodotorula, Sporobolomyces and Cystofilobasidium cultivated on glycerol substrate. Production of enriched yeast biomas and specific yeast metabolites (carotenoids, ergosterol, lipids) was evaluated on medium with glucose, pure technical glycerol and/or waste glycerol from biofuel production (40 g/L) and mixture of glycerol and glucose (1:3, 1:1, 3:1; C/N ratio 57 in all cultivations). All tested strains were able to utilize glycerol as the only carbon source. Production of biomass on waste glycerol was in most strains higher than in control as well as in medium with pure technical glycerol and reached 15.97–21.76 g/L. Production of carotenoids and ergosterol was better in glucose medium than in medium with glycerol only. Nevertheless, using glycerol medium with addition of glucose, higher yields of total carotenoids, beta-carotene and ergosterol were obtained than in control. The highest yields of total pigments were reached by Sporobolomyces roseus (3.60 mg/g cell dry weight (CDW); glycerol:glucose 1:3), Sporobolomyces salmonicolor (2.85 mg/g CDW; glycerol:glucose 1:3) and Rhodotorula glutinis (2.80 mg/g CDW; glycerol:glucose 3:1) In glucose medium, most tested strains except Cystofilobasidium capitatum (22.6 %) produced neutral lipids in the range of 11–15 %. Production of triacylglycerols in all strains was in 10–30 % better in glycerol medium, in which Rhodotorula aurantiaca and Sporobolomyces shibatanus also reached intracellular triacylglycerol concentrations up to 20 % of biomass. This study has shown that oleaginous red yeasts could have great potential for converting crude glycerol to valuable lipids and carotenoids in respect of efficient bioresources utilization.  相似文献   

19.
In this study, we investigated the induction of Pseudostellaria heterophylla adventitious root and the effects of sucrose concentration and phosphate source on biomass increase and metabolites accumulation. These roots were initially cultured in Murashige and Skoog medium for 4 weeks. IBA 3.0 mg L?1 proved to be the best auxin for inducing adventitious roots and the frequency of adventitious roots induced from roots (100 %) was higher than that from leaves (78 %) and stems (27 %). The medium with 4 % sucrose resulted in the optimum biomass i.e. 1.04 g/flask DW, and the content of saponin and polysaccharides reached the peak i.e. 0.676 and 24.4 %, respectively. With regards to phosphate source, 1.25 mM phosphate concentration was more favorable for biomass of roots (0.87 g/flask of DW), whereas the optimum saponin (0.74 %) and polysaccharides (22.09 %) were achieved with 2.5 mM phosphate. However, the saponin content at 2.5 mM phosphate did not show significant difference from the saponin content at 0.625 mM (0.69 %) or 3.75 mM phosphate (0.69 %).  相似文献   

20.
A recently isolated Australian Aurantiochytrium sp. strain TC 20 was investigated using small-scale (2 L) bioreactors for the potential of co-producing biodiesel and high-value omega-3 long-chain polyunsaturated fatty acids. Higher initial glucose concentration (100 g/L compared to 40 g/L) did not result in markedly different biomass (48 g/L) or fatty acid (12–14 g/L) yields by 69 h. This comparison suggests factors other than carbon source were limiting biomass production. The effect of both glucose and glycerol as carbon sources for Aurantiochytrium sp. strain TC 20 was evaluated in a fed-batch process. Both glucose and glycerol resulted in similar biomass yields (57 and 56 g/L, respectively) by 69 h. The agro-industrial waste from biodiesel production—glycerol—is a suitable carbon source for Aurantiochytrium sp. strain TC 20. Approximately half the fatty acids from Aurantiochytrium sp. strain TC 20 are suitable for development of sustainable, low emission sources of transportation fuels and bioproducts. To further improve biomass and oil production, fortification of the feed with additional nutrients (nitrogen sources, trace metals and vitamins) improved the biomass yield from 56 g/L (34 % total fatty acids) to 71 g/L (52 % total fatty acids, cell dry weight) at 69 h; these yields are to our knowledge around 70 % of the biomass yields achieved, however, in less than half of the time by other researchers using glycerol and markedly greater than achieved using other industrial wastes. The fast growth and suitable fatty acid profile of this newly isolated Aurantiochytrium sp. strain TC 20 highlights the potential of co-producing the drop-in biodiesel and high value omega-3 oils.  相似文献   

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