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1.
In this work, the effect of different inducing factors on trans-resveratrol extracellular production in Monastrell grapevine suspension cultured cells is evaluated. A detailed analysis
provides the optimal concentrations of cyclodextrins, methyljasmonate and UV irradiation dosage, optimal cell density, elicitation
time and sucrose content in the culture media. The results indicate that trans-resveratrol production decreases as the initial cell density increases for a constant elicitor concentration in Monastrell
suspension cultured cells treated with cyclodextrins individually or in combination with methyljasmonate; the decrease observed
in cell cultures elicited with cyclodextrins alone is far more drastic than those observed in the combined treatment. trans-Resveratrol extracellular production observed by the joint use of cyclodextrins and methyljasmonate (1,447.8 ± 60.4 μmol
trans-resveratrol g−1 dry weight) is lower when these chemical compounds are combined with UV light short exposure (669.9 ± 45.2 μmol trans-resveratrol g−1 dry weight). Likewise, trans-resveratrol production is dependent on levels of sucrose in the elicitation medium with the maximal levels observed with
20 g l−1 sucrose and the joint action of cyclodextrins and 100 μM methyljasmonate. The sucrose concentration did not seem to limit
the process although it affects significantly the specific productivity since the lowest sucrose concentration is 10 g l−1, the highest productivity is reached (100.7 ± 5.8 μmol trans-resveratrol g−1 dry weight g−1 sucrose) using cyclodextrins and 25 μM methyljasmonate. 相似文献
2.
The changes in foliar concentrations of volatile terpenes in response to water stress, fertilization and temperature were
analyzed in Pinus halepensis and Quercus ilex. The most abundant terpenes found in both species were α-pinene and Δ3-carene. β-Pinene and myrcene were also abundant in both species. P. halepensis concentrations were much greater than those of Q. ilex in agreement with the lack of storage in the latter species (15205.60 ± 1140.04 vs. 0.54 ± 0.08 μg g−1 [d.m.]). The drought treatment (reduction to 1/3 of full watering) significantly increased the total terpene concentrations
in both species (54% in P. halepensis and 119% in Q. ilex). The fertilization treatment (addition of either 250 kg N ha−1 or 250 kg P ha−1 or both) had no significant effects on terpene foliar concentrations. The terpene concentrations increased from 0.25 μg g−1 [d.m.] at 30°C to 0.70 μg g−1 [d.m.] at 40°C in Q. ilex (the non-storing species) and from 2,240 μg g−1 [d.m.] at 30°C to 15,621 μg g−1 [d.m.] at 40°C in P. halepensis (the storing species). Both species presented negative relationship between terpene concentrations and relative water contents
(RWC). The results of this study show that higher terpene concentrations can be expected in the warmer and drier conditions
predicted for the next decades in the Mediterranean region. 相似文献
3.
Sachin Kumar Surendra P. Singh Indra M. Mishra Dilip K. Adhikari 《Journal of industrial microbiology & biotechnology》2009,36(12):1483-1489
A yeast strain Kluyveromyces sp. IIPE453 (MTCC 5314), isolated from soil samples collected from dumping sites of crushed sugarcane bagasse in Sugar Mill,
showed growth and fermentation efficiency at high temperatures ranging from 45°C to 50°C. The yeast strain was able to use
a wide range of substrates, such as glucose, xylose, mannose, galactose, arabinose, sucrose, and cellobiose, either for growth
or fermentation to ethanol. The strain also showed xylitol production from xylose. In batch fermentation, the strain showed
maximum ethanol concentration of 82 ± 0.5 g l−1 (10.4% v/v) on initial glucose concentration of 200 g l−1, and ethanol concentration of 1.75 ± 0.05 g l−1 as well as xylitol concentration of 11.5 ± 0.4 g l−1 on initial xylose concentration of 20 g l−1 at 50°C. The strain was capable of simultaneously using glucose and xylose in a mixture of glucose concentration of 75 g l−1 and xylose concentration of 25 g l−1, achieving maximum ethanol concentration of 38 ± 0.5 g l−1 and xylitol concentration of 14.5 ± 0.2 g l−1 in batch fermentation. High stability of the strain was observed in a continuous fermentation by feeding the mixture of glucose
concentration of 75 g l−1 and xylose concentration of 25 g l−1 by recycling the cells, achieving maximum ethanol concentration of 30.8 ± 6.2 g l−1 and xylitol concentration of 7.35 ± 3.3 g l−1 with ethanol productivity of 3.1 ± 0.6 g l−1 h−1 and xylitol productivity of 0.75 ± 0.35 g l−1 h−1, respectively. 相似文献
4.
Mashitha Pise Jaishree Rudra Sunita Bundale Deovrat Begde Nandita Nashikkar Avinash Upadhyay 《In vitro cellular & developmental biology. Plant》2012,48(1):85-91
Asparagus racemosus is an important monocot medicinal plant that is in great demand for its steroidal saponins called shatavarins. This study
was initiated to optimize the conditions for production of shatavarins in cell cultures of A. racemosus in a modified Murashige and Skoog (MS) medium supplemented with six different combinations of growth regulators. Biomass
accumulation was correlated with saponin production over a 30-d culture cycle. Biomass and saponin accumulation patterns were
dependent on combinations of growth regulators and the pH of the medium. Maximum levels of saponin and biomass accumulation
were recorded on day 25 of the culture cycle within a pH range of 3.4 to 5.6. Total saponin produced by the in vitro cultures was 20-fold higher than amounts produced by cultivated plants. Saponin accumulation was not a biomass-associated
phenomenon; cultures which showed the highest biomass accumulation were not the highest saponin accumulators. Maximum biomass
(28.30 ± 0.29 g l−1) and maximum levels of shatavarin IV(11.48 ± 0.61 mg g−1) accumulation was found using a medium containing 2.0 mg l−1 2,4-D, 2 g l−1 casein hydrolysate and 0.005% pectinase. The highest levels of sarsapogenin, secreted and intracellular (4.02 ± 0.09 mg g−1), accumulated using a medium containing 1.0 mg l−1 NAA, 1.0 mg l−1 2,4-D, 0.5 mg l−1 BAP, 2 g l−1 casein hydrolysate and 0.005% pectinase, after 25 d. Shatavarins were secreted into the medium and can be isolated easily
for further purification. 相似文献
5.
J. López F. Lencina S. Petruccelli P. Marconi M. A. Alvarez 《Plant Cell, Tissue and Organ Culture》2010,103(3):307-314
We have established two transgenic cell suspension culture lines of Nicotiana tabacum that express the catalytic antibody 14D9 as a secretory product (sec-Ab) or as a KDEL-tagged product in the endoplasmic reticulum
(Ab-KDEL), respectively. After 3 years of culture, the performance improved to a production level of 0.15 ± 0.03 μg ml−1 on the seventh day of culture for the sec-Ab line and 0.48 ± 0.05 μg ml−1 on the third day for Ab-KDEL line. Analysis of the effect of osmotic stress using mannitol (90 g l−1) as an osmolite revealed that there was a 12-fold increase in antibody yield (1.96 ± 0.20 μg ml−1) on the seventh day of culture in line sec-Ab and a fivefold increase (2.31 ± 0.18 μg ml−1) on the seventh day for line Ab-KDEL. The concentration of the antibody in the culture medium was not significant. Dimethyl
sulfoxide used as a permeabilizing agent was not effective in increasing 14D9 yield, but it did cause distinctive cell damage
at all concentrations tested. 相似文献
6.
The algal, protozoan and metazoan communities within different drift-ice types (newly formed, pancake and rafted ice) and
in under-ice water were studied in the Gulf of Bothnia in March 2006. In ice, diatoms together with unidentified flagellates
dominated the algal biomass (226 ± 154 μg ww l−1) and rotifers the metazoan and protozoan biomass (32 ± 25 μg ww l−1). The under-ice water communities were dominated by flagellates and ciliates, which resulted in lower biomasses (97 ± 25
and 21 ± 14 μg ww l−1, respectively). The under-ice water and newly formed ice separated from all other samples to their own cluster in hierarchical
cluster analysis. The most important discriminating factors, according to discriminant analysis, were chlorophyll-a, phosphate and silicate. The under-ice water/newly formed ice cluster was characterized by high nutrient and low chlorophyll-a values, while the opposite held true for the ice cluster. Increasing trends in chlorophyll-a concentration and biomass were observed with increasing ice thickness. Within the thick ice columns (>40 cm), the highest
chlorophyll-a concentrations (6.6–22.2 μg l−1) were in the bottom layers indicating photoacclimation of the sympagic community. The ice algal biomass showed additional
peaks in the centric diatom-dominated surface layers coinciding with the highest photosynthetic efficiencies [0.019–0.032 μg C (μg Chl-a
−1 h−1) (μE m−2 s−1)−1] and maximum photosynthetic capacities [0.43-1.29 μg C (μg Chl-a
−1 h−1)]. Rafting and snow-ice formation, determined from thin sections and stable oxygen isotopic composition, strongly influenced
the physical, chemical and biological properties of the ice. Snow-ice formation provided the surface layers with nutrients
and possibly habitable space, which seemed to have favored centric diatoms in our study. 相似文献
7.
Mucor indicus can be used to produce ethanol from a variety of sugars, including pentose’s. An extract of it, produced by autolysis, could
replace yeast extract in culture medium with improved production of ethanol. At 10 g l−1, the extract gave a higher ethanol yield (0.47 g g−1) and productivity (0.71 g l−1 h−1) compared to medium containing yeast extract (yield 0.45 g g−1; productivity 0.67 g l−1 h−1). 相似文献
8.
Le Dinh Hung Kanji Hori Huynh Quang Nang Tran Kha Le Thi Hoa 《Journal of applied phycology》2009,21(3):265-272
The three color morphotypes of the red alga Kappaphycus alvarezii (brown, red and green) were cultured in Camranh Bay, Vietnam, using the fixed off-bottom monoline culture method to evaluate
the growth rate, carrageenan yield, 3,6-anhydrogalactose, gel strength and lectin content. The brown morphotype was cultivated
over a 12-month period; the red and green morphotypes were over a 6-month period. At the 60-day culture timepoint, the brown
morphotype showed a higher growth rate (3.5–4.6% day−1) from September to February, and lower growth rate (1.6–2.8% day−1) from March to August. Significant (P < 0.05) differences in growth rate between culture months were found with the brown morphotype. High growth rates for the
red (3.6–4.4% day−1) and green (3.7–4.2% day−1) morphotypes were obtained from September to February. The carrageenan yield, 3,6-anhydrogalactose and gel strength of the
three morphotypes showed little variation, with the highest values obtained in November–December. At the 30-day sampling point,
the brown morphotype had a higher lectin content (167–302 μg g−1 dry alga) from August to March and a lower lectin content (23–104 μg g−1 dry alga) from April to July. High lectin contents were recorded for the red (139–338 μg g−1 dry alga) and green (124–259 μg g−1 dry alga) morphotypes from September to February. This study shows that the different morphotypes of K. alvarezii can be grown in the tropical waters of the Camranh during the northeast monsoon, and part of the southwest monsoon, especially
the brown morphotype, which can be grown during any season. 相似文献
9.
Identification of QTL underlying isoflavone contents in soybean seeds among multiple environments 总被引:3,自引:0,他引:3
Guoliang Zeng Dongmei Li Yingpeng Han Weili Teng Jian Wang Liquan Qiu Wenbin Li 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(8):1455-1463
Soybean isoflavones are valued in certain medicines, cosmetics, foods and feeds. Selection for high-isoflavone content in
seeds along with agronomic traits is a goal of many soybean breeders. The aim of the study was to identify the quantitative
trait loci (QTL) underlying seed isoflavone content in soybean among seven environments in China. A cross was made between
‘Zhongdou 27’, a soybean cultivar with higher mean isoflavone content in the seven environments (daidzein, DZ, 1,865 μg g−1; genistein, GT, 1,614 μg g−1; glycitein, GC, 311 μg g−1 and total isoflavone, TI, 3,791 μg g−1) and ‘Jiunong 20’, a soybean cultivar with lower isoflavone content (DZ, 844 μg g−1; GT, 1,046 μg g−1; GC, 193 μg g−1 and TI, 2,061 μg g−1). Through single-seed-descent, 130 F5-derived F6 recombinant inbred lines were advanced. A total of 99 simple-sequence repeat markers were used to construct a genetic linkage
map. Seed isoflavone contents were analyzed using high-performance liquid chromatography for multiple years and locations
(Harbin in 2005, 2006 and 2007, Hulan in 2006 and 2007, and Suihua in 2006 and 2007). Three QTL were associated with DZ content,
four with GT content, three with GC content, and five with TI content. For all QTL detected the beneficial allele was from
Zhongdou 27. QTL were located on three (DZ), three (GC), four (GT) and five (TI) molecular linkage groups (LG). A novel QTL
was detected with marker Satt144 on LG F that was associated with DZ (0.0014 > P > 0.0001, 5% < R
2 < 11%; 254 < DZ < 552 μg g−1), GT (0.0027 > P > 0.0001; 4% < R
2 < 9%; 262 < GT < 391 μg g−1), and TI (0.0011 > P > 0.0001; 4% < R
2 < 15%; 195 < TI < 871 μg g−1) across the various environments. A previously reported QTL on LG M detected by Satt540 was associated with TI across four
environments and TI mean (0.0022 > P > 0.0001; 3% < R
2 < 8%; 182 < TI < 334 μg g−1) in China. Because both beneficial alleles were from Zhongdou 27, it was concluded that these two QTL would have the greatest
potential value for marker-assisted selection for high-isoflavone content in soybean seed in China.
G. Zeng, D. Li and Y. Han have equal contributions to the paper. 相似文献
10.
Experiments were conducted both under in vitro and in situ conditions to determine the biodegradation potential of button
mushroom spent substrate (SMS) and its dominating microbes (fungi and bacteria) for carbendazim and mancozeb, the commonly
used agricultural fungicides. During 6 days of incubation at 30 ± 2°C under broth culture conditions, highest degradation
of carbendazim (17.45%) was recorded with B-1 bacterial isolate, while highest degradation of mancozeb (18.05%) was recorded
with Trichoderma sp. In fungicide pre-mixed sterilized SMS, highest degradation of carbendazim (100.00–66.50 μg g−1) was recorded with mixed inoculum of Trichoderma sp. and Aspergillus sp., whereas highest degradation of mancozeb (100.00–50.50 μg g−1) was with mixed inoculum of Trichoderma sp., Aspergillus sp. and B–I bacterial isolate in 15 days of incubation at 30 ± 2°C. All these microbes both individually as well as in different
combinations grew well and produced extracellular lignolytic enzymes on SMS, which helped in fungicides degradation. Under
in situ conditions, among three different proportions of SMS (10, 20 and 30%, w/w) mixed with fungicide pre-mixed soil (100 μg g−1 of soil), the degradation of carbendazim was highest in 30% SMS treatment, while for mancozeb it was in 20% SMS treatment.
The residue levels of both fungicides decreased to half of their initial concentration after 1 month of SMS mixing. 相似文献
11.
M. A. Sobrado 《Trees - Structure and Function》2009,23(2):429-437
This study estimated the construction const (CC) and maintenance cost (MC) of leaf tissue on the basis of dry mass (CCMass, MCMass) and leaf area (CCArea, MCArea), as well as the maximum leaf gas exchange capacity, so as to examine leaf cost:benefit relationship in six dominant species
of the ‘Bana’ vegetation. Minimum and maximum CCMass averaged 1.71 ± 0.03 and 1.78 ± 0.03 g glucose g−1. The CCMass showed a statistically significant positive correlation with crude fibre, and tended to decline as leaves were larger. Thus,
smaller leaves tended to be built out of a more expensive material than that found in species bearing larger leaves. The average
CCArea of the ‘Bana’ species was 376 ± 15 g glucose m−2. A robust correlation was found between CCArea with leaf dry mass to leaf area ratio, as well as with leaf thickness, but not with leaf density. MCMass (g glucose g−1 day−1) and MCArea (g glucose m−2 day−1) were positively correlated. Maximum and minimum MCMass increased significantly with protein and lipid content, respectively. Maximum carbon assimilation (A
max) was positively correlated with CCArea. All the species operated at high stomatal conductance (g
s) and C
i/C
a which suggested low short-term water use efficiency. Potential nitrogen use efficiency (PNUE = A
max/N) averaged 35.4 ± 1.8 mmol CO2 mol−1 N. As the sclerophylly index (g crude fibre g−1 protein) increased, the ratio of CCArea to A
max increased significantly. This result suggests a trade-off between investments in an expensive resistant sclerophyllous leaf
which should maximize carbon gain in the long term. 相似文献
12.
Hong-Yang Zhu Hong Xu Xiao-Yan Dai Yang Zhang Han-Jie Ying Ping-Kai Ouyang 《Bioprocess and biosystems engineering》2010,33(5):565-571
A new yeast, isolated from natural osmophilic sources, produces d-arabitol as the main metabolic product from glucose. According to 18S rRNA analysis, the NH-9 strain belongs to the genus
Kodamaea. The optimal culture conditions for inducing production of d-arabitol were 37 °C, neutral pH, 220 rpm shaking, and 5% inoculum. The yeast produced 81.2 ± 0.67 g L−1
d-arabitol from 200 g L−1
d-glucose in 72 h with a yield of 0.406 g g−1 glucose and volumetric productivity
Q\textP Q_{\text{P}} of 1.128 g L−1 h−1. Semi-continuous repeated-batch fermentation was performed in shaker-flasks to enhance the process of d-arabitol production by Kodamaea ohmeri NH-9 from d-glucose. Under repeated-batch culture conditions, the highest volumetric productivity was 1.380 g L−1 h−1. 相似文献
13.
Fungal biomass in the decaying cones ofPinus densiflora was investigated. Leaching, immobilization and mobilization phases were recognized in the decomposition process of cones.
Fungal biomass was estimated by the agar-film technique, using a conversion factor of 0.62 mg dry wt. mm−3 of hyphal volume to biomass and a factor of 2.5 for in-efficiencency of homogenization. The fungal biomass was 4.9±2.1 (mean±S.D.)
mg dry wt. g−1 dry matter in the cones on the tree, 11±6 mg g−1 in the leaching phase, 19±7 mg g−1 in the immobilization phase and 30±15 mg g−1 in the mobilization phase. It significantly increased after cones had lain on the forest floor, and also in the immobilization
phase. The latter result suggests that the fungal biomass contributed to the immobilization of nitrogen in the decomposition
process. The ratio of ergosterol content to fungal biomass in the cones was 2.9–8.8 μg mg−1 dry wt., lying in the range of 2–16 μg mg−1 reported for mycelia. This suggested that the estimate of fungal biomass was reasonable. Reduction in this ratio with the
dry weight loss in the cones suggested that the proportion of relatively active fungal biomass decreased with the progress
of decomposition. 相似文献
14.
Irzykowska L Bocianowski J Waśkiewicz A Weber Z Karolewski Z Goliński P Kostecki M Irzykowski W 《Journal of applied genetics》2012,53(2):237-247
Thirty single-spore isolates of a toxigenic fungus, Fusarium oxysporum, were isolated from asparagus spears and identified by species-specific polymerase chain reaction (PCR) and translation elongation
factor 1-α (TEF) sequence analysis. In the examined sets of F. oxysporum isolates, the DNA sequences of mating type genes (MAT) were identified. The distribution of MAT idiomorph may suggest that MAT1-2 is a predominant mating type in the F. oxysporum population. F. oxysporum is mainly recognised as a producer of moniliformin—the highly toxic secondary metabolite. Moniliformin content was determined
by high-performance liquid chromatography (HPLC) analysis in the range 0.05–1,007.47 μg g−1 (mean 115.93 μg g−1) but, also, fumonisin B1 was detected, in the concentration range 0.01–0.91 μg g−1 (mean 0.19 μg g−1). There was no association between mating types and the mycotoxins biosynthesis level. Additionally, a significant intra-species
genetic diversity was revealed and molecular markers associated with toxins biosynthesis were identified. 相似文献
15.
Latiporn Udomsuk Thaweesak Juengwattanatrakul Kanokwan Jarukamjorn Waraporn Putalun 《Acta Physiologiae Plantarum》2012,34(3):1093-1100
Miroestrol and deoxymiroestrol are highly active phytoestrogens derived from the tuberous roots of Pueraria candollei var. mirifica. To date, there have been no reports regarding the production of miroestrol and deoxymiroestrol in in vitro cell culture.
In this study, callus and cell suspension cultures were established for the purpose of investigating miroestrol and deoxymiroestrol
content in P. candollei var. mirifica cells. Stem-derived callus cultured on Murashige and Skoog (MS) medium supplemented with 0.1 mg l−1 thidiazuron (TDZ), 0.5 mg l−1 naphthaleneacetic acid (NAA), and 1.0 mg l−1 benzyladenine (BA) provided optimal conditions for the accumulation of deoxymiroestrol and total isoflavonoids. The calli
produced 184.83 ± 20.09 μg g−1 dry weight of total chromene and 20.72 ± 2.38 mg g−1 dry weight of total isoflavonoid. This is the first report to suggest that callus culture is a suitable alternative method
for producing miroestrol and deoxymiroestrol. Carbon sources were evaluated for the cell suspension cultures of P. candollei var. mirifica. Sucrose provided optimal conditions for biomass production, whereas fructose was the most suitable carbon source for deoxymiroestrol
and isoflavonoid production. The information from our study can be employed for enhancing the production of miroestrol, deoxymiroestrol,
and total isoflavonoids using in vitro cell culture of P. candollei var. mirifica. 相似文献
16.
Hossein Vaheed Seyed Abbas Shojaosadati Hasan Galip 《Journal of industrial microbiology & biotechnology》2011,38(1):101-111
In this research, ethanol production from carob pod extract (extract) using Zymomonas mobilis with medium optimized by Plackett–Burman (P–B) and response surface methodologies (RSM) was studied. Z. mobilis was recognized as useful for ethanol production from carob pod extract. The effects of initial concentrations of sugar, peptone,
and yeast extract as well as agitation rate (rpm), pH, and culture time in nonhydrolyzed carob pod extract were investigated.
Significantly affecting variables (P = 0.05) in the model obtained from RSM studies were: weights of bacterial inoculum, initial sugar, peptone, and yeast extract.
Acid hydrolysis was useful to complete conversion of sugars to glucose and fructose. Nonhydrolyzed extract showed higher ethanol
yield and residual sugar compared with hydrolyzed extract. Ethanol produced (g g−1 initial sugar, as the response) was not significantly different (P = 0.05) when Z. mobilis performance was compared in hydrolyzed and nonhydrolyzed extract. The maximum ethanol of 0.34 ± 0.02 g g−1 initial sugar was obtained at 30°C, initial pH 5.2, and 80 rpm, using concentrations (g per 50 mL culture media) of: inoculum
bacterial dry weight, 0.017; initial sugar, 5.78; peptone, 0.43; yeast extract, 0.43; and culture time of 36 h. 相似文献
17.
Effects of sequential procedures required for cryopreservation of embryos excised from the recalcitrant seeds of Haemanthus montanus were assessed ultrastructurally and in conjunction with respiratory activity and the rate of protein synthesis. Fresh material
(water content, 5.05 ± 0.92 g g−1 dry mass) afforded ultrastructural evidence of considerable metabolic activity, borne out by respiratory rates. Neither exposure
to glycerol nor sucrose as penetrating and non-penetrating cryoprotectants, respectively, brought about degradative changes,
although increased vacuolation and autophagy accompanied both, while respiratory and protein synthetic activity were not adversely
affected. Glycerol-cryoprotected embryos flash dried to water contents >0.4 g g−1 showed organised ultrastructural features and considerable autophagy consistent with metabolic activity, and although respiratory
activity was lower, protein synthesis rate was enhanced relative to fresh material. However, at water contents <0.4 g g−1, embryo tissue presented a mosaic of cells of variable density and ultrastructural status, but trends in rates of respiration
and protein synthesis remained similar. Flash drying after sucrose exposure was accompanied by considerable ultrastructural
abnormality particularly at water contents <0.4 g g−1, lysis of individual and groups of cells and considerable depression of respiration, but not of protein synthesis. Success,
assessed as ≥50% axes forming seedlings after cryogen exposure, was obtained only when glycerol-cryoprotected embryos at water
contents >0.4 g g−1—in which the degree of vacuolation remained moderate—were rapidly cooled. The outcomes of this study are considered particularly
in terms of the stresses imposed by prolonged, relatively slow dehydration and ultimate water contents, on embryos showing
considerable metabolic activity. 相似文献
18.
Seasonal dynamics of major biochemical features were studied for three abundant egg-diapausing copepods Acartia
bifilosa, Centropages hamatus and Temora longicornis, in the White Sea (66°N), between June 2002 and September 2002. Dry weight (DW) and prosome length varied from 0.54 μg ind−1 and 0.163 ± 0.012 mm (A. bifilosa, CI) to 9.58 ± 0.72 μg ind−1 and 1.135 ± 0.167 mm (C. hamatus, females). Corg and Norg content reached up to 5.91 ± 0.44 and 1.23 ± 0.09 μg ind−1 (C. hamatus, females). Protein and lipid content varied greatly from 31.8 to 67.3% DW and from 8.7 to 42.6% DW, respectively. These species
show somewhat different biology compared to species at lower latitudes. The copepods use lipid stores to survive during short-term
food shortage (e.g. in autumn) and successfully complete their life cycle. In the isolated White Sea during last post-glacial
period, species probably evolved some special biochemical features (especially wax esters presence). Food quality demands
and long ice coverage are possible factors limiting early development of species in spring. 相似文献
19.
Hui Li Hong Xu Hao Xu Sha Li Han-Jie Ying Ping-Kai Ouyang 《Bioprocess and biosystems engineering》2011,34(1):95-102
Batch fermentative production of welan gum by Alcaligenes sp. CGMCC2428 was investigated under various oxygen supply conditions using regulating agitation speed. Based on a three
kinetic parameters analysis that includes specific cell growth rate (μ), specific glucose consumption rate (q
s), and specific welan formation rate (q
p), a two-stage agitation speed control strategy was proposed to achieve high concentration, high yield, and high viscosity
of welan. During the first 22 h, the agitation speed in 7.5 L fermenter was controlled at 800 rpm to maintain high μ for cell growth. The agitation was then reduced step-wise to 600 rpm to maintain a changing profile with stable dissolved
oxygen levels and obtain high qp for high welan accumulation. Finally, the maximum concentration of welan was reached at 26.3 ± 0.89 g L−1 with a yield of 0.53 ± 0.003 g g−1 and the welan gum viscosity of 3.05 ± 0.10 Pa s, which increased by an average of 15.4, 15.2, and 20.1% over the best results
controlled by constant agitation speeds. 相似文献
20.
Waldemar Rymowicz Alina R. Fatykhova Svetlana V. Kamzolova Anita Rywińska Igor G. Morgunov 《Applied microbiology and biotechnology》2010,87(3):971-979
Yarrowia lipolytica A-101-1.22 produces high citric acid (112 g l−1) with a yield of 0.6 g g−1 and a productivity of 0.71 g l−1 h−1 during batch cultivation in the medium with glycerol-containing waste of biodiesel industry. However, it was observed that
the specific citric acid production rate, which was maximal at the beginning of the biosynthesis, gradually decreases in the
late production phase and it makes continuation of the process over 100 h pointless. The cell recycle and the repeated batch
regimes were performed as ways for prolongation of citric acid synthesis by yeast. Using cell recycle, the active citric acid
biosynthesis (96–107 g l−1) with a yield of 0.64 g g−1 and a productivity of 1.42 g l−1 h−1 was prolongated up to 300 h. Repeated batch culture remained stable for over 1000 h; the RB variant of 30% feed every 3 days
showed the best results: 124.2 g l-1 citric acid with a yield of 0.77 g g-1 and a productivity of 0.85 g l-1 h-1. 相似文献