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Incubation
About: Incubation is a research topic. Over the lifetime, 5748 publications have been published within this topic receiving 126541 citations.
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TL;DR: High yields of an alkaline protease were obtained in batch fermentation of a Bacillus sp.
Abstract: High yields (1939 U/ml) of an alkaline protease were obtained in batch fermentation of a Bacillus sp. using a response surface methodology. The interaction of four variables, viz., starch, peptone, incubation time, and inoculum density, suggested inoculum density to be an insignificant variable. However, incubation time had a profound effect on protease yields at all the concentrations of carbon and nitrogen used. The response surface raised and flattened with increase in time of incubation, and maximum protease production up to 1939 U/ml was obtained after 96 h of incubation. The model equation obtained was validated experimentally at maximum starch (15 mg/ml) and peptone (7.5 mg/ml) concentration with increased incubation time up to 144 h in the presence of minimum inoculum density (1%). An overall 2.6-fold increase in protease production was obtained as compared with mean observed response (750 U/ml) at zero level of all variables.
290 citations
TL;DR: An early function in translation is shown to be rate limiting at the elevated temperature and is the cause of polyribosome disaggregation and an RNA factor is produced which appears to promote the association of ribosomes with messenger RNA.
281 citations
TL;DR: It is demonstrated why linear correlation analyses across a wide range of temperatures can be inappropriate based on development of an incubation model for small birds that incorporates how ambient temperature influences both embryonic development and adult metabolism.
Abstract: Ambient temperature is commonly thought to influence avian incubation behavior. However, results of empirical studies examining correlations between ambient temperature and bout duration are equivocal. We propose that these equivocal results can be partly explained by developing a conceptual understanding of how we should expect temperature to influence incubation. We demonstrate why linear correlation analyses across a wide range of temperatures can be inappropriate based on development of an incubation model for small birds that incorporates how ambient temperature influences both embryonic development and adult metabolism. We found support for predictions of the model using incubation data from orange-crowned warblers (Vermivora celata) in Arizona. Both off- and on-bout duration were positively correlated with ambient temperature between 9 and 26C, but unrelated to ambient temperature 9 and 26–40C. Bout durations declined as ambient temperature approached or exceeded 40C. Incubating orange-crowned warblers appeared to avoid bouts off the nest 7 min and bouts on the nest 20 min. Time of day, duration of the previous bout, and variation among nests all explained variation in both onand off-bout duration. Although we found support for the general shape of the incubation model, temperature still explained only a small portion of the overall variation in on- and off-bout duration. Results of previous studies were generally consistent with the model for off-bout duration; most studies in colder environments reported positive correlations with temperature, and the one negative correlation reported was from a hot environment. However, the relationships between on-bout duration and temperature reported in previous studies were less consistent with our model and our data. Although some discrepancies could be explained by considering our model, some studies reported negative correlations in cold environments. The effect of ambient temperature on duration of on-bouts probably differs among species based on the amount of fat reserves females typically carry during incubation and the extent of male incubation feeding. Additional studies of the effects of temperature on avian incubation will help improve the general model and ultimately aid our understanding of energetic and ecological constraints on avian incubation. Key words: ambient temperature, foraging, incubation behavior, incubation model, incubation rhythm, nest attentiveness, on-bout duration, off-bout duration. [Behav Ecol 11:178–188 (2000)]
277 citations
TL;DR: Variations in temperature and time of incubation, inoculum size, type and concentration of carbon source, type of nitrogen source, and presence of various substances with known action on fungal morphogenesis altered growth in many cases, but did not significantly affect the patterns of vegetative morphogenesis conditioned by each atmosphere of incubators; however, vegetative Morphogenesis was strongly affected by addition of certain chelating agents.
Abstract: Bartnicki-Garcia, S. (Rutgers, The State University, New Brunswick, N.J.) and Walter J. Nickerson. Nutrition, growth, and morphogenesis of Mucor rouxii. J. Bacteriol. 84:841-858. 1962.-Mucor rouxii was grown under three different atmospheres of incubation: air, N(2), and CO(2) in parallel cultures. The atmosphere of incubation markedly affected nutritional requirements, growth, and morphogenesis. Absence of oxygen greatly reduced growth and increased the nutritional demands of the fungus. Presence of a high tension of CO(2) resulted in a change from filamentous to yeastlike morphogenesis. Aerobically, a large variety of carbon sources was utilized; anaerobically, only hexoses served to meet requirements for carbon and energy. Aerobically, various amino acids supported abundant growth; anaerobically, they were poorly utilized. Ammonium and nitrate ions were better sources of nitrogen for anaerobic growth. In general, incubation under either air or N(2) resulted in development of coenocytic filamentous mycelium, whereas incubation under CO(2) resulted in development of budding yeastlike cells. Variations in temperature and time of incubation, inoculum size, type and concentration of carbon source, type of nitrogen source, and presence of various substances with known action on fungal morphogenesis altered growth in many cases, but did not significantly affect the patterns of vegetative morphogenesis conditioned by each atmosphere of incubation. However, vegetative morphogenesis was strongly affected by addition of certain chelating agents. Yeastlike development of M. rouxii was prevented by ethylene-diaminetetraacetic acid (EDTA) in concentrations which were also partially inhibitory for growth; under these conditions, development was filamentous. Chemically related chelating agents were similarly active. The growth-inhibitory and morphogenetic effects of EDTA were reversed by transition-group metal ions. Yeastlike development of M. subtilissimus, which does not require CO(2) for its induction, was also inhibited by EDTA.
276 citations
TL;DR: Observations are consistent with the hypothesis that the preimplantation mammalian embryo produces a factor(s) which can stimulate its own development and have implications for clinical in-vitro fertilization, where embryos are routinely cultured individually in relatively large volumes.
Abstract: The morphology, cleavage rate and viability of preimplantation embryos from random bred Swiss mice were assessed after culture in different incubation volumes and embryo densities. Decreasing the incubation volume, from 320 to 20 microliters, significantly increased blastocyst cell number (P less than 0.01) and embryo development after transfer (P less than 0.01). Increasing the number of embryos incubated per drop from 1 to 16 significantly increased the number of two-cell embryos reaching the blastocyst stage in 5 or 320 microliters. Culturing embryos in groups significantly increased blastocyst cell numbers in all volumes employed and elevated embryo viability. Such observations are consistent with the hypothesis that the preimplantation mammalian embryo produces a factor(s) which can stimulate its own development. The results of this study have implications for clinical in-vitro fertilization, where embryos are routinely cultured individually in relatively large volumes.
274 citations