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1.
Cultural conditions on mycelial growth and fruit-body formation ofMycena chlorophos were studied. The optimum temperature of the mycelial growth was 27°C and the optimum initial pH of medium was 4.0. Peptone
agar medium was suitable for the spawn culture. Compost medium containing rice bran at 10% (fw/fw) was appropriate for fruitbody
formation in the Petri dish. Light was essential for initiation of primordia, and low-temperature treatment induced fruit-body
formation effectively. The optimum conditions for fruit-body formation were found to be the cultivation at 27°C for 4 wk and
continued cultivation for 3 wk under illumination at an intensity above 0.2 lx and at 21°C after casing with moist compost
powder. In the fruit-bodies obtained, the maximum photosensitive wavelength of luminescence was 522 nm and the optimum temperature
for emission was 27°C. The luminescence of a fruit-body was observed for about 3 d consecutively at 21°C. 相似文献
2.
Efficient production of poly(l-lactide)(PLA)-degrading enzyme was achieved by addition of 0.1% (w/v) silk fibroin powder into a liquid culture medium of an actinomycete, Amycolatopsis orientalis, without other complex nitrogen sources, such as yeast extract and peptone. Scaled-up production of the enzyme in a 5-l jar fermenter showed the possibility of producing this enzyme on an industrial scale at low production cost. The extracellular PLA-degrading enzyme showed potent degrading activity, which is effective for biological recycling of PLA, i.e., 2,000 mg/l of PLA powder was completely degraded within 8 h at 40°C using 20 mg/l purified enzyme. An optically active l-lactic acid with 600 mg/l was obtained as degradation product of PLA without undesirable racemization. 相似文献
3.
Pious Thomas 《In vitro cellular & developmental biology. Plant》1998,34(1):52-56
Summary
In vitro rooted grape (Vitis vinifera L.) plantlets (4 or 8 wk from culturing microcuttings) were plantedex vitro in polythene sachets (24×12 cm) filled to one-third their height with planting mixture. The sachets were misted, closed,
and incubated at ambient temperature (25–30°C) under 16 h photoperiod (40–50 μ E·m−2.·sec−1) for 1,2, or 3 wk before opening. Maximum establishment with no or minimum damage toin vitro formed leaves was obtained with 3 wk of closed sachet incubation in both age groups. Opening the sachet at 2 wk from planting
resulted in marginal scorching of lower leaves and some reduction in establishment and vigor. Opening at 1 wk led to severe
leaf scorching and significant reduction in establisment particularly in 4-wk-oldin vitro plantlets while growth was more affected in 8-wk-old ones. Relative humidity ofin vitro culture vessel was 68–75% while closed sachets had RH values of 45–77% depending on length of incubation and ambient RH.
Diurnal variation in RH of sachet in relation to ambient RH was the major factor that facilitated acclimatization rather than
the overall fall in RH during the period of closed incubation. Satisfactory acclimatization of plantlets to withstand the
open sachet RH (50–55%) by 3 wk and the ambient RH (30–40%) by 4 wk was achieved. Monitoring water loss from detached leaves
of plantlets showed a significant reduction between the date of planting and Week 3, and again between Weeks 3 and 4. Comparison
of growthin vitro andex vitro suggested that shifting toex vitro earlier was more beneficial. This observation was confirmed by transferring 3-, 4-, and 5-wk-old plantlets fromin vitro rooting medium toex vitro and recording the growth at 8 wk fromin vitro culturing when 3 wkin vitro plus 5 wkex vitro combination showed maximum vigor. The leftover stumps after subculturing of 1–4-mo.-old stock cultures could also be effectively
used forex vitro establishment. 相似文献
4.
Tremacoldi C.R. Watanabe N.K. Carmona E.C. 《World journal of microbiology & biotechnology》2004,20(6):639-642
The production of extracellular acid proteases from Aspergillus clavatus was evaluated in a culture filtrate medium, with different carbon and nitrogen sources. The fungus was cultivated at three
different temperatures during 10 days. The proteolytic activity was determined on haemoglobin pH 5.0 at 37 °C. The highest
acid proteolytic activity (80 U/ml) was observed in culture medium containing glucose and gelatin at 1%(w/v) at 30 °C at the
third day of incubation. Cultures developed in Vogel medium with glucose at 2%(w/v) showed at about 45% of proteolytic activity
when compared to the cultures with 1% of the same sugar. The optimum pH of enzymatic activity was 2.0 and the enzyme was stable
at pH values ranging from 2.0 to 4.0. The optimum temperature was 40 °C and the half-lives at 40, 45 and 50 °C were 30, 10
and 5 min, respectively.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
Cultivation characteristics of fruit-body (synnema) formation ofIsaria japonica were examined using liquid and solid media in order to produce fruit-bodies on a large scale. Mycelia grew well at 18–28°C
on PDA medium with an initial pH of 7.0. The formation of fruit-bodies ofI. japonica was induced by lowering temperature to below 20°C in PD liquid medium. In sawdust-rice bran basal medium mixed with pupal
powder prepared from silkworms (Bombyx mori), the fresh weight of fruit-bodies increased with increasing content of pupal powder. The highest yields of fruit-bodies
were obtained in carbon-rich barley grain medium supplemented with pupal powder. The fruit-bodies grown under CO2 concentrations of 1,000 μl/L had coral-like, many-branched synnemata with numerous conidiospores, whereas those formed under
high concentrations (9,000 μl/L) of CO2 had unbranched and longer synnemata. High concentrations of CO2 remarkably inhibited conidiospore formation on synnemata. Continuous high-intensity illumination at 2.93 W·m−2 inhibited the elongation of synnemata, and low-intensity illumination at 0.088 W·m−2 slightly inhibited the branching of synnemata. Fruit-bodies were produced on the pupa metamorphosed from living larvae ofAgrotis fucosa placed on the surface of a culture ofI. japonica incubated in sawdust-rice bran medium. 相似文献
6.
Takashi Yamanaka 《Mycoscience》1994,35(2):187-189
Lyophyllum tylicolor, which forms mycelial basidia (and basidiospores), produced fruit-bodies when cultivated at 20°C under continuous illumination
of 400–700 lux on agar plates containing Bacto-Soytone and glucose or an extract from urea-treated soil. Under these conditions,
mycelial basidia were also observed on the Soytone-glucose agar, but not on the soil extract agar. In darkness, fruit-bodies
and mycelial basidia were not observed on either medium. In culture on the soil extract agar, fruit-body primordia were produced
at the position of the margin of the colony when it was transferred from darkness to continuous light; stipes did not elongate
under illumination of ca. 2000 lux; and mycelial basidia and basidiospores, but not fruit-bodies, developed when glucose concentration
in the medium was as high as 1% (w/v). 相似文献
7.
Elaine F. Smith Andrew V. Roberts John Mottley 《Plant Cell, Tissue and Organ Culture》1990,21(2):129-132
Plantlets of Chrysanthemum x morifolium were grown from nodal sections in cellulose plugs which were saturated with liquid rooting medium containing 1 mg l–1 paclobutrazol in culture vessels that maintained relative humidities (RH) of 100%, 96% and 94%, respectively. After 4 weeks, plantlets were transferred to compost and exposed to 40% RH at 29°C. Marked differences in wilting were observed that were directly related to the RH of the vessel in which the plantlets had been grown. Thicker leaves, improved closure of stomata and increased thickness of the cuticle were associated with increased resistance to wilting. Reduced RH of the culture vessel was also associated with significantly higher concentrations of chlorophyll in the leaves. 相似文献
8.
Thangam E. Berla Rajkumar G. Suseela 《World journal of microbiology & biotechnology》2000,16(7):663-666
Alcaligenes faecalis produced extracellular protease when incubated in media containing protein substrates. Enzyme production was found to be
influenced by various culture conditions. Enzyme production was growth-associated, expressed linearity with growth and reached
a maximum at the end of the growth phase. Carbohydrates and inorganic nitrogen sources could not be utilized by the bacterium
for its growth, and organic nitrogen appeared to be a primary determinant in protease production. Enzyme production reached
its maximum level of 171.2 U/ml when the culture was incubated at 30 °C at pH 8.0. Ca2+ and Mg2+ enhanced the enzyme production. The crude enzyme powder was stable at high alkaline pH and stable upto 6 months at the storage
temperature of 0–4 °C.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
Heleomyza borealis Boh. (Diptera, Heleomyzidae) overwinters as larvae in Arctic habitats, where they may experience winter temperatures below ? 15°C. The larvae freeze at c.? 7°C but in acclimation experiments 80% survived when exposed to ? 60°C. Of the larvae exposed to between ? 4 and ? 15°C, only 3% pupated. However, when cooled to ? 20°C this increased to 44%, with 4% emerging as adults. Larvae maintained at 5°C contained low levels of glycerol, sorbitol and trehalose, which did not increase with acclimation to low temperatures. However, levels of fructose increased from 6.1 μg mg?1 fw in control animals to 17 μg mg?1 fw when exposed to ? 2°C for 1 week. Larval body water (2.2 ± 0.1 g/g dw, mean ± SD, n = 100) and lipid content (0.22 ± 0.002 g/g fw, mean ± SE) showed no significant change during acclimation to low temperatures. Larvae maintained at a constant 5°C survived for over 18 months with little loss of body mass (from 7.5 ± 1.2 to 7.0 ± 1.2 mg fw, mean ± SD, n = 20), but none pupated. Heleomyza borealis larvae appear to feed and grow until they reach a body mass of about 7.5 mg and then become dormant. They remain in this state until they experience a low temperature stimulus (< ? 15°C) followed by a warm period (≈ 5°C). This ensures that the larvae pupate and adults emerge in early summer, allowing the maximum growing period before the following winter. Heleomyza borealis are adapted to survive long winters in a dormant larval state. They have a low metabolic rate, can conserve body water even at subzero temperatures but do not synthesize large quantities of cryoprotectants. 相似文献
10.
Mycoplasma contamination affects many different aspects of cell culturing, resulting in unreliable experimental results and
potentially harmful biological products. Therefore, the specificity, sensitivity, and reliability of detecting mycoplasma
contamination are important aspects of quality control in biotechnological products. In this study, Mycoplasma hyorhinis was adopted as a model strain to evaluate the effects of storage on the viability of Mycoplasma species in cell culture samples.
Medium X was compared with conventional media 243 and 988 for the ability to detect M. hyorhinis. The 101 CFU/ml of M. hyorhinis was inoculated into medium X prepared using the same lots of components and preserved for 7 d, 1 mo, and 2 mo. M. hyorhinis grew readily and typically on agar plates prepared within 1 mo. The viable mycoplasmas in samples containing different initial
titers (101 and 106 CFU/ml) after storage at 4° C and −30° C were analyzed. During storage, viable organisms were found with little or no reduction
in titers after storage for 8 wk at −30° C under aerobic and anaerobic conditions. A reduction in titers of 3 log10 occurred
after 4 wk storage for high-dose cultures (106 CFU/ml) at 4° C. The titers of viable organisms were diminished over 8 wk at 4° C under aerobic and anaerobic conditions. 相似文献
11.
Badawi A. Abou-Awad Mahmoud M. Al-Azzazy Sahar I. Afia 《Archives Of Phytopathology And Plant Protection》2013,46(19):1862-1866
Studies on biology of Oligonychus mangiferus (Rahman and Sapra) at combination of eight constant temperatures and relative humidities (RHs) viz., 7.0°C with 85% RH, 10°C with 80% RH, 15.0°C with 75% RH, 23.0°C with 70% RH, 31.0°C with 65% RH, 34.0°C with 65% RH, 36.0°C with 60% RH and 40.0°C with 55% RH revealed that the optimal condition for the development of these mites are 15.0–31.0°C and 65–75% RH. The highest temperature and the lowest RH accelerated the rate of development and induced more reproduction of O. mangiferus. Its population also multiplied 30.81 times in a generation time of 27.36 days at 31.0°C and 65% RH, while the same population only increased 7.46 times in a generation time of 48.07 days at 15.0°C and 75% RH. Fecundity was highest at 31.0°C and 65% RH with 46.43 eggs per female. The highest intrinsic rate of natural increase was observed at 31.0°C as 0.125 per day. 相似文献
12.
S. Prakash Y. Veeranagouda L. Kyoung K. Sreeramulu 《World journal of microbiology & biotechnology》2009,25(2):197-204
A halophilic and alkali-tolerant Chromohalobacter sp. TPSV 101 with an ability to produce extracellular halophilic, alkali-tolerant and moderately thermostable xylanase was
isolated from solar salterns. Identification of the bacterium was done based upon biochemical tests and 16S rRNA sequence.
The culture conditions for higher xylanase production were optimized with respect to NaCl, pH, temperature, substrates and
metal ions and additives. Maximum xylanase production was achieved in the medium with 20% NaCl, pH-9.0 at 40°C supplemented
with 1% (w/v) sugarcane bagasse and 0.5% feather hydrolysate as carbon and nitrogen sources. Sugarcane bagasse (250 U/ml)
and wheat bran (190 U/ml) were the best inducer of xylanase when used as carbon source as compared to xylan (61 U/ml). The
xylanase that was partially purified by protein concentrator had a molecular mass of 15 kDa approximately. The xylanase from
Chromohalobacter sp. TPSV 101 was active at pH 9.0 and required 20% NaCl for optimal xylanolytic activity and was active over a broad range
of temperature 40–80°C with 65°C as optimum. The early stage hydrolysis products of sugarcane bagasse were xylose and xylobiose,
after longer periods of incubation only xylose was detected. 相似文献
13.
Amir Daryaei E. Eirian Jones Travis R. Glare Richard E. Falloon 《Biocontrol Science and Technology》2016,26(1):86-103
Identification of the production and storage factors that affect conidium germination and bioactivity (fitness) will assist the success of biological control agents. Effects of culturing conditions on conidium fitness of Trichoderma atroviride LU132 were examined in different storage conditions over time. Abiotic factors (temperature, nutrients, water activity and pH) during production were studied. Conidia from the culturing regimes which resulted in greatest and least bioactivity against Rhizoctonia solani in dual culture were selected to assess effects of storage conditions on conidium fitness. Fitness of the test conidia was examined after storage at 30°C and at 0% or 50% relative humidity (RH) over 6 months. Fitness declined over time, and the decline was greater for 50% RH than 0% RH, probably through reduced metabolic activity of conidia during long-term storage. Stored conidia were probably affected by dehydration, temperature and other factors such as oxidation, before and during storage, and also by rehydration after storage. The greatest number of conidia and germination percentage resulted from production at 25°C, but greatest bioactivity resulted from those produced at 30°C. No significant effects on bioactivity were detected between the conidium production treatments C?:?N 5?:?1 and C?:?N 160?:?1, indicating that C?:?N ratio in culture medium is not important for conidium survival of T. atroviride. 相似文献
14.
Temperature preferences of the mite, Alaskozetes antarcticus, and the collembolan, Cryptopygus antarcticus from the maritime Antarctic 总被引:2,自引:0,他引:2
Abstract. The thermal preferences of Alaskozetes antarcticus (Acari, Cryptostigmata) and Cryptopygus antarcticus (Collembola, Isotomidae) were investigated over 6 h within a temperature gradient (?3 to +13 °C), under 100% relative humidity (RH) conditions. After 10 days of acclimation at ?2 or +11 °C, individual supercooling points (SCP) and thermopreferences were assessed, and compared with animals maintained for 10 days under fluctuating field conditions (?6 to +7 °C). Acclimation at ?2 °C lowered the mean SCP of both A. antarcticus (?24.2 ± 9.1) and C. antarcticus (?14.7 ± 7.7) compared to field samples (?19.0 ± 9.0 and ?10.7 ± 5.2, respectively). Acclimation at +11 °C increased A. antarcticus mean SCP values (?13.0 ± 8.5) relative to field samples, whereas those of C. antarcticus again decreased (?16.7 ± 9.1). Mites acclimated under field conditions or at +11 °C selected temperatures between ?3 and +1 °C. After acclimation at ?2 °C, both species preferred +1 to +5 °C. Cryptopygus antarcticus maintained under field conditions preferred +5 to +9 °C, whereas individuals acclimated at +11 °C selected +9 to +13 °C. For A. antarcticus, thermopreference was not influenced by its cold hardened state. The distribution of field specimens was further assessed within two combined temperature and humidity gradient systems: (i) 0–3 °C/12% RH, 3–6 °C/33% RH, 6–9 °C/75% RH and 9–12 °C/100% RH and (ii) 0–3 °C/100% RH, 3–6 °C/75% RH, 6–9 °C/33% RH and 9–12 °C/12% RH. In gradient (i), C. antarcticus distributed homogeneously, but, in gradient (ii), C. antarcticus preferred 0–3 °C/100% RH. Alaskozetes antarcticus selected temperatures between 0 and +6 °C regardless of RH conditions. Cryptopygus antarcticus appears better able than A. antarcticus to opportunistically utilize developmentally favourable thermal microclimates, when moisture availability is not restricted. The distribution of A. antarcticus appears more influenced by temperature, especially during regular freeze‐thaw transitions, when this species may select low temperature microhabitats to maintain a cold‐hardened state. 相似文献
15.
Light initiated fruit body primordia of Coprinus congregatus Bull, ex Fr. grown at relatively high temperature (25°C) require a single dark period or low-temperature induction for completion of fruit-body development. The dark period requirement varied with the temperature regime during the inductive dark period A minimum requirement of 2.5 h was found al 15–20°C. Darkness always promotes development of fruit-body primordial, but cannot, be regarded as an absolute necessity until temperature exceeds about 17.5°C. Normal development of me primordia without darkness was obtained by lowering the temperature to 10°C for 6 h. It appeared that at high temperatures two successive stimuli were required for basidiocarp maturation, a light-off and a subsequent signal light-on signal. On the contrary, at 10°C a single low-temperature signal seemed to be involved. Thus, induction of fruit-body development could be produced by alternative pathways. These developmental features have been extended to other fungi and compared with the flowering processes of some short-day plants. 相似文献
16.
The optimization of culture conditions for the bacteriumPseudomonas aeruginosa BYK-2 KCTC 18012P, was performed to increase its rhamnolipid production. The optimum level for carbon, nitrogen sources,
temperature and pH, for rhamnolipid production in a flask, were identified as 25 g/L fish oil, 0.01% (w/v) urea, 25 and pH
7.0, respectively. Optimum conditions for batch culture, using a 7-L jar fermentor, were 200 rpm of agitation speed and a
2.0 L/min aeration rate. Under the optimum conditions, on fish oil for 216 h, the final cell and rhamnolipid concentrations
were 5.3 g/L and 17.0 g/L respectively. Fed-batch fermentation, with different feeding conditions, was carried out in order
to increase, cell growth and rhamnolipid production by thePseudomonas aeruginosa, BYK-2 KCTC 18012P. When 2.5 g of fish oil and 100 mL basal salts medium, containing 0.01% (w/v) urea, were fed intermittently
during the fermentation, the final cell and rhamnolipid concentrations at 264 h, were 6.1 and 22.7 g/L respectively. The fed-batch
culture resulted in a 1.2-fold increase in the dry cell mass and a 1.3-fold increase in rhamnolipid production, compared to
the production of the batch culture. The rhamnolipid production-substrate conversion factor (0.75 g/g) was higher than that
of the batch culture (0.68 g/g). 相似文献
17.
The aim of this study was to investigate under a controlled environment, the effect of temperature on the survival and infectivity
of Pseudotheraptus devastans Distant, a cassava anthracnose disease vector. The insect P. devastans was collected from young cassava (Manihot esculenta Crantz) field plots, at the International Institute of Tropical Agriculture, (IITA), Ibadan, Nigeria. A mixture of the different
developmental stages of eggs, first to fifth instar nymphs, and adults, were incubated in controlled environment chambers,
under various constant temperatures of: 15, 17, 22, 25, 27, 30, and 35°C. Relative humidity at different temperature conditions
were recorded and maintained at 90%, 85%, 80%, 75%, 70%, 65%, and 60%, respectively. A significant increase in insect survival
was observed between 22 and 27°C temperature conditions while a significant decrease in survival was observed at 15°C and
above 30°C. Lesion number, lesion diameter and infectivity among the insect stages varied as a function of temperature and
relative humidity. Infectivity was highest at 22–25°C maintained at 75–80% RH and lowest at 15°C and above 30°C maintained
respectively, at 65% RH and 90% RH. There was considerable low vector infectivity due to low survival of the insects at extreme
temperatures. 相似文献
18.
Graves T Narendranath NV Dawson K Power R 《Applied microbiology and biotechnology》2007,73(5):1190-1196
The combined effects of lactic acid and acetic acid on ethanol production by S. cerevisiae in corn mash, as influenced by temperature, were examined. Duplicate full factorial experiments (three lactic acid concentrations
× three acetic acid concentrations) were performed to evaluate the interaction between lactic and acetic acids on the ethanol
production of yeast at each of the three temperatures, 30, 34, and 37°C. Corn mash at 30% dry solids adjusted to pH 4 after
lactic and acetic acid addition was used as the substrate. Ethanol production rates and final ethanol concentrations decreased
(P<0.001) progressively as the concentration of combined lactic and acetic acids in the corn mash increased and the temperature
was raised from 30 to 37°C. At 30°C, essentially no ethanol was produced after 96 h when 0.5% w/v acetic acid was present
in the mash (with 0.5, 2, and 4% w/v lactic acid). At 34 and 37°C, the final concentrations of ethanol produced by the yeast
were noticeably reduced by the presence of 0.3% w/v acetic acid and ≥2% w/v lactic acid. It can be concluded that, as in previous
studies with defined media, lactic acid and acetic acid act synergistically to reduce ethanol production by yeast in corn
mash. In addition, the inhibitory effects of combined lactic and acetic acid in corn mash were more apparent at elevated temperatures. 相似文献
19.
《Journal of Fermentation and Bioengineering》1994,77(5):490-495
Aspergillus oryzae produced a small amount of lipase (0.05–0.8 U/wet-g of solid medium) in solid cultures, in contrast to the larger amount (0.46 U/ml) in a shake-flask culture in a modified GYP medium containing 2% glucose, 1% yeast extract and 2% Polypepton. Optimum conditions of lipase production in the submerged culture of A. oryzae were determined in terms of pH, composition of medium, and temperature. In a shake-flask culture at 28°C, the maximum amount of lipase increased to 0.78 U/ml upon the addition of 3% soybean oil to the modified GYP medium. In a jar fermentor culture, 30 U/ml lipase activity was obtained after 72 h at 28°C under appropriate conditions. Lipase production was greatly influenced by the culture temperature, and the optimum temperature for lipase production was about 24°C with a narrow temperature range, which was 10 degrees lower than that for the growth. In the submerged cultures, two kinds of lipase at least exhibiting different substrate specificities were also suggested. 相似文献
20.
Tigressa H. S. Rodrigues Gustavo A. S. Pinto Luciana R. B. Gonçalves 《Biotechnology and Bioprocess Engineering》2008,13(5):571-576
In this study, the optimization of tannase production by solid state fermentation was investigated using cashew apple bagasse
(CAB), an inexpensive residue produced by the cashew apple agroindustry, as a substrate. To accomplish this, CAB was enriched
with 2.5% (w/w) tannic acid and 2.5% (w/w) ammonium sulphate and then moistened with water (60 mL/100 g of dry CAB). The influence
of inoculum concentration (104 to 107 spores/g), temperature (20, 25, 30, and 35°C) and several additional carbon sources (glucose, starch, sucrose, maltose, analytical
grade glycerol, and glycerol produced during biodiesel production) on enzyme production by Aspergillus oryzae was then evaluated. Supplementation with maltose and glycerol inhibited tannase synthesis, which resulted in lower enzyme
activity. Starch and sucrose supplementation increased enzyme production, but decreased the enzyme productivity. The maximum
tannase activity (4.63 units/g of dry substrate) was obtained at 30°C, using 107 spores/g and 1.0% (w/v) sucrose as an additional carbon source. 相似文献