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1.
Excised root cultures of soya bean cultured at 30 °C inWhite's medium (1943) supplemented with 01 per cent yeastextract have been serially sub-cultured over 13 culture passagesof 7 days although a decline in the linear growth and lateralformation begins in the third passage and the roots are devoidof laterals from the 8th passage onwards. Applications of abscisicacid within the concentration range 0010001mg l1 and during the first two culture passages enhancedthe linear growth of the main axis, the number of emergent lateralsand the total length of laterals. This effect has been shownfor two cultivars, with roots derived from seed in both itsfirst and second year of storage and under different conditionsof culture and culture pH. 相似文献
2.
Callus and suspension cultures of Theobroma cacao L., initiatedfrom immature cotyledons of beans from pods harvested 120130days after pollination were established. A modified B-5 or MurashigeSkoogagar medium sustained growth of callus without loss of vigourafter each sub-culture. A 15-fold weight increase occurred duringthe 4 week culture periods at 30 ± 1 °C. Coconutwater improved callus growth substantially. The optimum hormonalconcentrations for growth of suspensions were 0.5 mg 11of 2, 4-dichlorophenoxyacetic acid and 0.1 mg I1 of kinetinin a MurashigeSkoog basal medium liquid medium. The optimumtemperature for growth of suspensions was 2530 °C.The cell number and cell mass of suspensions increased 20-foldin 14 days. No organogenesis or embryogenesis was observed. Theobroma cacao L., acao, cell culture, suspension culture, tissue culture. 相似文献
3.
Jeffke T Jende D Mätje C Ehlers RU Berthe-Corti L 《Applied microbiology and biotechnology》2000,54(3):326-330
Photorhabdus luminescens, a bacterial symbiont of entomopathogenic biocontrol nematodes, was grown in batch and glucose fed-batch culture. The cell
density, bioluminescence, production of antibiotic substances, number of cells with inclusion bodies, glucose concentration
and oxygen uptake rate were recorded. The addition of 12.4 g l−1 glucose prolonged the growth, and the yield almost doubled, from 6.85 g l−1 to 12.45 g l−1 dry mass. The production of antibiotic substances increased by 140%. Bioluminescence was higher in the batch culture. A shift
of P. luminescens to phase II variants was not detected.
Received: 21 January 2000 / Received revision: 3 April 2000 / Accepted: 7 April 2000 相似文献
4.
Several clones of Douglas-fir, Pseudotsuga menziesii (Mirb.)Franco, embryos grown in aseptic culture in the presence orabsence of the female gametophyte or a crushed aqueous extractof it, have shown striking differences in overall length, sizeand substance(s) responsible for this colour of the cotyledonsand in root length. The growth-promoting effect is diffusiblein agar, heat-stable and has detectable activity at a concentrationof about 0·1 to 1·0 per cent (v/v) in a basalnutrient medium. Evidence is provided that extracts of gametophytemay have synergistic effects with coconut water in promotingmorphogenesis of Douglas-fir cells in suspension culture. Pseudotsuga menziesii, Douglas-fir, female gametophyte, einbryo culture 相似文献
5.
Immature Glycine max (L.) Merr. seeds initially at 5070mg fresh weight were successfully grown and matured in vitroin detached pods. Surface sterilized pods were floated in aliquid medium containing 5 per cent sucrose, minerals, and glutaminein 125 ml Erlenmeyer flasks and incubated at 25 °C under350400 µE m1 s1 white light. Seedswhich were matured in vitro increased tenfold in dry weight,were visually similar to commercial seeds of the same size,were tolerant to desiccation and germinated with normal seedlinggrowth. Excised pods transported dye from the pedicel to thegrowing seed within 120 min. Soya bean pod culture is a usefultechnique to study the influence of single or combinations ofchemical or environmental parameters on regulation of seed growth,seed maturation, and subsequent germination events without theconfounding interactions with the mother plant. Glycine max (L.) Merr., soya bean, pod culture, seed culture, seed growth, seed maturation, germination 相似文献
6.
Summary We have examined the MGH-U1 human bladder carcinoma cell line and 12 primary bladder carcinoma biopsies for their ability
to form spheroids in suspension culture and in multiwell dishes. MGH-U1 cells formed tightly packed spheroids with a necrotic
center and viable rim whereas three sublines formed loose aggregates only. Spheroids formed from as few as 100 MGU-U1 cells
placed into multiwells. MGH-U1 cells derived from spheroids formed new spheroids more rapidly and consistently than cells
derived from monolayer culture. Spheroid diameter increased at a rapid rate of ∼100 μm/d in multiwell dishes, and necrosis
occurred only in spheroids of diameter >1 mm. Spheroids placed in spinner culture at a higher concentration (∼1.5 spheroids/ml)
grew more slowly and developed necrosis at smaller diameters. The width of the viable rim of spheroids grown in spinner culture
was maintained at ∼190 μm over a wide range of spheroid diameters (400 to 1000 μm). Sequential trypsinization of spheroids,
which stripped layers of cells from the spheroids, demonstrated no difference in the plating efficiency of cells derived from
varying depths into the spheroid. Only one of the 12 primary bladder biopsy specimens demonstrated an ability to form spheroids.
This biopsy, designated HB-10, formed spheroids that grew linearly over 40 d, formed colonies in methylcellulose culture and
grew as xenografts in immune-deprived mice. These studies characterize the MGH-U1 spheroids that are useful in vitro models
to study the effects of various treatments for solid tumors and demonstrate the limited capacity of cells from primary human
bladder biopsies to form spheroids.
Supported in part by a grant from the National Cancer Institute of Canada and by grant CA29526 NCI through the National Bladder
Cancer Project, U.S.A. 相似文献
7.
Gracilaria is a potentially valuable source of marine biopolymers such as proteins and polysaccharides. In order to select suitable culture conditions, growth and tolerance of Gracilaria chorda Holmes from Shikoku Island in southwest Japan were investigated under variations of temperature (5–30 ∘C), photon irradiance (20–120 μmol photons m−2 s−1), and photoperiod (12:12 h, 14:10 h light:dark regime) in a unialgal culture. Gracilaria chorda showed wide tolerances for all factors investigated, which is characteristic of eurythermal species. Maximum growth was observed at 18–24 ∘C. The optimum photon irradiance for the algal growth was 60–120 μmol photons m−2s−1. Instead of using ordinary sea salt (NaCl) to prepare artificial seawater, ultra pure salt was adopted. Gracilaria chorda grew faster in artificial seawater made with ultra-pure salt than that made with ordinary sea salt, probably because the former medium was clear, while the latter was milky. Effects of some metal ions on the growth were tested with artificial seawater. Iron ions affected algal growth, but cobalt ions did not. This study enables us to determine suitable culture conditions for G. chorda. A scaled-up 30 l culture of G. chorda under such conditions was successful. 相似文献
8.
Grapevine microcuttings grown in vitro were subjected to differentculture conditions within the framework of a factorial experiment.Threefactors were studied: genotype, sucrose content of the mediumand physical conditions of culture. There were three valuesor three different cases for each controlled factor, leadingto a total of 27 experimental batches and 15 induced variableswere measured. These concerned growth of plants, uptake of carbohydratesfrom the medium and uptake of essential minerals. Analysis ofthe results revealed the overall action of each of the threecontrolled factors. These actions were significant in most cases.At 21°C, genotype and culture conditions influenced length,fresh and dry weight of the plants and the amounts of carbohydratesand nitrate taken up; however, the relative dry matter contentof plants remained normal. In contrast, when the greater partof the culture was carried out at 12°C (long-term cultureconditions) the percentage dry weight increased considerably. Key words: Vitis, in vitro, nutrition 相似文献
9.
The physiological characteristics of cultures of very high cell mass (e.g. 10 g cell mass/L), termed “ultrahigh cell density cultures” is reviewed. A close relationship was found between the length
of the optical path (OP) in flat-plate reactors and the optimal cell density of the culture as well as its areal (g m−2 day−1) productivity. Cell-growth inhibition (GI) unfolds, as culture density surpasses a certain threshold. If it is constantly
relieved, a 1.0 cm OP reactor could produceca. 50% more than reactors with longer OP,e.g. 5 or 10 cm. This unique effect, discovered by Hu et al. [3], is explained in terms of the relationships between the frequency
of the light-dark cycle (L-D cycle), cells undergo in their travel between the light and dark volumes in the reactor, and
the turnover time of the photosynthetic center (PC). In long OP reactors (5 cm and above) the L-D cycle time may be orders
of magnitude longer than the PC turnover time, resulting in a light regime in which the cells are exposed along the L-D cycle,
to long, wasteful dark periods. In contrast, in reactors with an OP ofca. 1.0 cm, the L-D cycle frequency approaches the PC turnover time resulting in a significant reduction of the wasteful dark
exposure time, thereby inducing a surge in photosynthetic efficiency. Presently, the major difficulty in mass cultivation
of ultrahigh-density culture (UHDC) concerns cell grwoth inhibition in the culture, the exact nature of which is awaiting
detailed investigation. 相似文献
10.
Soya Bean Seed Growth and Maturation In vitro without Pods 总被引:2,自引:0,他引:2
OBENDORF R. L.; TIMPO E. E.; BYRNE M. C.; TOAI T. V.; RYTKO G. T.; HSU F. C.; ANDERSON B. G. 《Annals of botany》1984,53(6):853-863
Immature Glycine max (L.) Merrill seeds, initially between 50and 450 mg f. wt, were grown and matured successfully in vitro.Excised seeds were floated in a liquid medium containing 5 percent sucrose, minerals and glutamine in flasks incubated at25 °C under 300 to 350 µE m2 s1 fluorescentlight. During 16 to 21 d in culture, seeds grew to a matured. wt of 100 to 600 mg per seed at an average rate of 5 to 25mg d. wt per seed d1 depending on initial size. Growthrates were maximal during the first 8 to 10 d in vitro but declinedwith loss of green colour in the cotyledons. Seed coats rupturedwith rapid cotyledon expansion during the first 2 d in culture.Embryos were tolerant to desiccation and 80 to 90 per cent germinatedif removed from culture before complete loss of green colour.The growth of excised seeds in vitro exceeded the growth ofseeds in detached pods, but when windows were cut in pods topermit direct exposure of seeds to the medium, seed growth wascomparable. Glycine max (L.) Merrill, soya bean, seed culture, seed growth, seed maturation, germination 相似文献
11.
A number of substances have been found which can replace 2:4-dichlorophen-oxyaceticacid (2:4-D) as a synergist with coconut milk in stimulatingthe growth of potato tuber tissue in culture. Two of these compounds,viz. -(2-naphthoxy)-and -(2: 4: 5-trichlorophenoxy)-propionicacids, are optically active and their (+)- and ()-enantiomorphshave also been examined for synergistic activity. In each casethe (+)-form was found to be highly active and the ()-forminactive. Evidence is also presented showing that the inactive()-isomer of a-(2-naphthoxy)propionic acid can depressthe synergistic activity of the (+)-isomer and it is suggestedthat this occurs by competitive antagonism. 相似文献
12.
The kinetics of growth, nutrient uptake, and anthraquinone biosynthesisby suspension cultures of Galium mollugo L. cells were examinedin batch and continuous (chemostat) culture. In batch culture,although the initial growth rate was constant (minimum doublingtime = 35 h) characteristic changes in cell composition wereobserved during the growth cycle particularly cell dry weight(between 3.9 and 9.2 g/109 cells), cell anthraquinone (2280mg/109 cells), and cell protein (0.71.6 g/109 cells).Using a chemostat steady state growth was established at twodifferent specific growth rates with mean doubling times of40 h and 25 h. Phosphate was established as the growth-limitingnutrient in chemostat culture at a concentration of 11 µgP ml1. In steady state growth at a doubling time of 40h the cell composition remained constant although this was differentfrom any cells grown in batch culture. The cell anthraquinonelevel in steady state growth was between 7 and 30 times lowerthan in batch culture. This result raises the question of therelative importance of growth rate and the growth-limiting nutrientin determining accumulation of secondary products by culturedplant cells. 相似文献
13.
S F Cavalitto R A Hours C F Mignone 《Journal of industrial microbiology & biotechnology》2000,25(5):260-265
Geotrichum klebahnii ATCC 42397 produces a protopectinase (PPase-SE) with polygalacturonase (PGase) activity. The microorganism was aerobically
cultivated in synthetic media. Glucose, fructose and xylose yielded the highest enzyme levels (10–11 PGase units ml−1). Galacturonic acid repressed enzyme production and no growth was obtained with disaccharides and pectin. Specific enzyme
activity obtained in an O2-limited culture was similar to that found in nonlimited ones. A growth yield (Y
x/s) of 0.49 g of cell dry weight per gram of glucose consumed was obtained in a typical batch bioreactor culture. Enzyme production
was growth associated, and no major products other than biomass and CO2 were detected. The volumetric enzyme activity reached a maximum around D=0.3–0.4 h−1 in glucose-limited continuous cultures. However, it varied strongly (together with microorganism morphology) even after retention
times ≥8 at any D tested (0.035–0.44 h−1) though the rest of the culture variables remained fairly constant. No correlation between morphology and enzyme activity
could be obtained. Enzyme production was poor in urea- and vitamin-limited continuous cultures. In all cases, biomass and
CO2 accounted for ≅100% of carbon recovery though Y
x/s values were different. Journal of Industrial Microbiology & Biotechnology (2000) 25, 260–265.
Received 20 April 2000/ Accepted in revised form 15 September 2000 相似文献
14.
Soybean [Glycine max (L.) Merrill] seeds and cotyledons weregrown in an in vitro culture system to investigate the relationshipsbetween cell expansion (net water uptake by the seed) and drymatter accumulation. Seeds or cotyledons grown in a completenutrient medium containing 200 mol m3 sucrose continueddry matter accumulation for up to 16 d after in planta seedsreached physiological maturity (maximum seed dry weight). Seedor cotyledon water content increased throughout the cultureperiod and the water concentration remained above 600 g kg1fresh weight. These data indicate that the cessation of seeddry matter accumulation is controlled by the physiological environmentof the seed and is not a pre-determined seed characteristic.Adding 600 mol m3 mannitol to the medium caused a decreasein seed water content and concentration. Seeds in this mediumstopped accumulating dry matter at a water concentration ofapproximately 550 g kg1. The data suggest that dry matteraccumulation by soybean seeds can continue only as long as thereis a net uptake of water to drive cell expansion. In the absenceof a net water uptake, continued dry matter accumulation causesdesiccation which triggers maturation. Key words: Glycine max (L.) Merrill, solution culture, duration of seed growth, water content, dry matter accumulation 相似文献
15.
M A Jackson J S Frymier B J Wilkinson P Zorner S Evans 《Journal of industrial microbiology & biotechnology》1998,21(4-5):237-241
Xanthomonas campestris MB245, a specific pathogen of the weedy grass Poa annua (annual bluegrass), is being developed as a bioherbicide to control this pest in turf. Nutritional and environmental factors
were evaluated based on their ability to support rapid submerged culture growth and high cell yield. Temperature optima for
the growth of X. campestris cells in submerged culture were between 27 and 30°C. At 30°C, optimal nutritional conditions for X. campestris growth supported generation times of 150–175 min and cell yields after 24 h growth of 1–2 × 1010 cells ml−1. Media containing sucrose or glucose as the carbon source and various organic nitrogen sources supported optimal X. campestris growth and cell yield. The addition of vitamin mixtures to complex and defined media had no significant effect on growth
or cell yield. The age of X. campestris cultures had a significant impact on cell survival after freeze drying. Following freeze drying, log phase cell survival
(44%) was significantly lower than early and late stationary phase cell survival, 62% and 68%, respectively. Cells harvested
in stationary phase, freeze dried and stored under vacuum at 4°C, showed no significant loss in viability after 6 months.
Thus, high cell concentrations of the bioherbicide X. campestris can be rapidly produced in submerged culture and stabilized as freeze-dried preparations.
Received 14 August 1998/ Accepted in revised form 8 October 1998 相似文献
16.
Batch cultures of photoautotrophic cell suspensions of Chenopodiumrubrum L., growing in an inorganic medium on CO2 under a daily balanced light–dark regime of 16 : 8 h could be maintained for approximately 100 d without subcultivation.
The long-lived cultures showed an initial cell division phase of 4 weeks, followed by a stationary phase of another 4 weeks,
after which ageing and progressive cell death reduced the number of living cells and the cultures usually expired after another
3–4 weeks. These developmental phases of the cell culture were characterised with respect to photosynthetic performance, dark
respiration, content of phytohormones and capacity of cell division. Cell division of the majority of the cells finished in
the G1- or G0-phase of the cell cycle, caused by a pronounced decline in the endogenous levels of auxin and cytokinins. Supply
of these growth factors to resting cells resulted in resumption of cytokinesis, at least by some of the cells. However, responsiveness
to the phytohomones declined during the stationary phase, and subcultivation was no longer possible beyond day 60 when the
phases of ageing and death commenced. Ageing was characterised by a further decline in the photosynthetic capacity of the
cells, by a climacteric enhancement of dark respiration, but also by a slight increase in the level of IAA and cytokinins
concomitant with a decrease in ethylene. Similarities and differences between the development of batch-cultured photoautotrophic
cells of C. rubrum and that of a leaf are discussed with respect to using the cell culture as a model for a leaf.
Received: 30 April 1999 / Accepted: 21 August 1999 相似文献
17.
To date, plantlet culture has not been explored as a means to obtain secondary metabolites in vitro. However, plantlets readily produce desirable secondary metabolites, which may not be produced in cell suspension or callus
cultures. To optimize plantlet growth in vitro, the influences of various physical environments on the growth (fresh weight), morphogenesis (leaf, root, and shoot number),
and volatile carbon metabolites (i.e. monoterpene, (−)-carvone) of Mentha spicata L. (spearmint) plants were studied. The carvone content in different portions of sterile plantlets was analyzed. Carvone
was only produced from the foliar regions of cultured plantlets and was absent in the callus and roots. The influence of physical
support (e.g., agar, glass gravel, liquid, platform or sponge), frequency of media replacement, and culture vessel capacity
on spearmint plantlets growth and carvone production was tested. A comparative study was conducted testing the growth, morphogenesis,
and secondary metabolism occurring with three different spearmint cultivars grown in either culture tubes containing 25 ml
agar medium or in an automated plant culture system (APCS; a sterile hydroponics system) employing a 1-l medium reservoir.
Increasing the number of media immersions (4, 8, 12 or 16 immersions d−1) of plantlets growing in the APCS increased growth and morphogenesis responses. Generally, higher culture growth rates resulted
in lower carvone treatment−1 (mg carvone g-FW−1); however, overall total carvone ((mg carvone g-FW−1) × g culture FW) increased because of the production of greater biomass obtained per vessel. 相似文献
18.
Summary The growth parameters of Acinetobacter calcoaceticus, relevant to its mass cultivation on acetate and ethanol, were determined in batch and continuous culture experiments. Acetic
acid exhibited a more powerful inhibitory effect on the growth rate than ethanol. In batch culture, the acetate component
of an acetate-ethanol substrate pair was preferentially utilized, but diauxic growth as such was not evident. The temperature
optimum for growth was in the region of 29°–36°C, and the cell yield did not change appreciably over this temperature range.
In carbon-limited chemostat cultures, the maximum specific growth rates on acetate and ethanol were 1.22 h−1 and 0.96 h−1 respectively, and the respective yield coefficients were 0.4 and 0.75. A high maintenance energy requirement was exhibited,
especially during acetate-limited growth. The respiratory quotient was dependent on the growth rate, the significance of which
is discussed.
Part of the material included in this paper was presented at the VIth International Fermentation Symposium, London, Ontario,
July 1980 相似文献
19.
Muster Peter; Binder Andres; Schneider Kurt; Bachofen Reinhard 《Plant & cell physiology》1983,24(2):273-288
The thermophilic cyanobacterium Mastigocladus laminosus wasgrown in a steady state continuous culture. Regulation and datasampling of the turbidostat was done with a microcomputer. Growthperformance was measured as a function of temperature and pHfrom 30 to 62°C and between pH 4 and 10. The temperatureoptimum was between 45 and 55°C. Under optimal conditionsthe filaments contained predominantly 8 cells with a high phycocyanincontent but at the temperature extremes and at high pH, 2- and4-cell filaments containing little phycocyanin were more abundant. (Received July 30, 1982; Accepted January 6, 1983) 相似文献
20.
R. L. Jarret 《Journal of Plant Growth Regulation》1997,16(4):227-231
Plant growth retardants were evaluated for their ability to reduce the growth rate of sweetpotato (Ipomoea batatas (L.) Lam.) in vitro. Nodal sections of cv. Jewel were cultured for 30 days on medium containing NDA, ancymidol, phosfon,
TIBA, difenzoquat, chlormequat, ACC, mepiquat chloride, or daminozide at 0, 10−4, 10−5, 10−6, 10−7, or 10−8
m. Difenzoquat, NDA, phosfon, and TIBA, at 10−4
m, were lethal to axillary bud explants. A low concentration (10−8
m) of chlorflurenol or NDA stimulated shoot elongation. The effective concentration range for most growth retardants was 10−5 to 10−6
m. Small (2- to 4-mm diameter) storage root-like swellings were observed on roots in cultures containing TIBA or ancymidol.
The growth-inhibiting effects of ancymidol and NDA were transitory and did not persist through a 180-day culture period. Shoots
cultured on medium containing 10−5
m phosfon, TIBA, or difenzoquat were significantly shorter than control plants after a 180-day culture period. Culture on medium
containing TIBA, NDA, ancymidol, or ACC resulted in abnormal leaf and stem development. Plants derived from nodal explants
cultured on medium containing either phosfon or chlormequat were near normal in appearance but with some plants exhibiting
interveinal chlorosis and reduced root system development.
Received May 9, 1997; accepted August 14, 1997 相似文献