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901.
Surya Sudheer Zain Taha Sivakumar Manickam Asgar Ali Poh Guat Cheng 《Fungal biology》2018,122(5):293-301
Following the importance of antler-type fruiting bodies of Ganoderma lucidum, in this study, the impact of main growth parameters such as ventilation and light on the development of antler-type fruiting bodies has been investigated together with the determination of physico-chemical properties of antler fruiting bodies. For this, the primordia bags of G. lucidum were kept under controlled ventilation to adjust the CO2 produced by the mushrooms owing to its respiration under light and dark conditions. The bioactive compounds such as phenolics, flavonoids, water-soluble polysaccharides and ganoderic acid showed a two-fold increase in the antler-type fruiting bodies as compared to normal kidney-shaped fruiting bodies. It is assumed from this study that the antler type fruiting bodies are developed due to restricted ventilation which causes an increase in the level of CO2 gas in the air as a result of respiration of mushroom. The shape and colour of antler fruiting bodies again dependent on the light provided in the growth chamber. This study also proves that with the manipulation of light and ventilation antler-type fruiting bodies of G. lucidum could be developed with higher quantity of bioactive compounds and with higher antioxidant potential. 相似文献
902.
Dolores Solis Juan J Calvete Libia Sanz Christiane Hettel Manfred Raida Teresa Diaz-Maurino Edda Topfer-Petersen 《Glycoconjugate journal》1997,14(2):275-280
Lectin mapping, carbohydrate analysis and electrospray mass spectrometry of boar seminal plasma PSP-II glycoforms show that
its single N-glycosylation site displays a repertoire of carbohydrate structures consisting of the basic pentasaccharide core
Manα 1–6[Manα 1–3]Manβ1-4GlcNAcβ1-4GlcNAc with a fucosyl residue α1-6-linked to the innermost N-acetylglucosamine residue. Other glycoforms display fucosylated hybrid-type or monoantennary complex-type chains, some of
which contain α2-6-linked sialic acid. N-acetylgalactosamine, possibly in Galβ1-3GalNAc sequence, is present in most of the PSP-II glycoforms. Abbreviations: PSP-I and PSP-II, porcine seminal plasma proteins
I and II; PNGaseF, peptide-N4-(N-acetyl-β-D-glucosaminyl) asparagine amidase (EC 3.5.1.52) from Flavobacterium meningosepticum;
ConA, Cannavalia ensiformis (jack bean) agglutinin; GNA, Galanthus nivalis (snowdrop) agglutin; SNA, Sambucus nigra (elderberry)
agglutinin; MAA, Maackia amurensis (maakia) agglutinin; PNA, Arachis hypogaea (peanut) agglutinin; DSA, Datura stramonium
(jimson weed) agglutinin; AAA, Aleuria aurantia agglutinin
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
903.
Alexandra Portele Jürgen Lenz Milan Höofer 《Journal of bioenergetics and biomembranes》1997,29(6):603-609
A model of membrane potential-dependent distribution of oxonol VI to estimate the electrical potential difference across Schizosaccharomyces pombe plasma membrane vesicles (PMV) has been developed. was generated by the H+-ATPase reconstituted in the PMV. The model treatment was necessary since the usual calibration of the dye fluorescence changes by diffusion potentials (K+ + valinomycin) failed. The model allows for fitting of fluorescence changes at different vesicle and dye concentrations, yielding in ATP-energized PMV of 80 mV. The described model treatment to estimate may be applicable for other reconstituted membrane systems. 相似文献
904.
Abstract The supercooling points of cold (-10C and -5C) and heat (37 C, 40 C and 45 C) shocked overwintering larvae were nearly the same as that of un-shocked ones (ca. -20C). Temperature shocks enhanced the ability to endure subzero temperature (- 15C, 3 h), and the cold shock treatment had more significant effect on maintaining larval survival than that of heat shock. It is the third insect that heat shock and cold shock enhanced its survival rate under low temperature simultaneously. A special stress protein (MW = 83 kD) was expressed under cold shock at -10 C and heat shock at 40 C or 45 C. It is also a few instances that a stress protein was expressed in the same insect under both heat shock and cold shock simultaneously. Meanwhile, the antioxidant system under different treatments was studied. Rapid cold hardening process had no oxidative stress because of the increase content of reduced glutathione and activity of glutathione reductase, but other treatments had. 相似文献
905.
SCOTT L. PARKER ROBIN M. ANDREWS TOM MATHIES 《Biological journal of the Linnean Society. Linnean Society of London》2004,83(3):289-299
Viviparity in reptiles is hypothesized to evolve in cold climates at high latitudes and high elevations through selection for progressively longer periods of egg retention. Oxygen consumption of embryos increases during development and therefore longer periods of egg retention should be associated with maternal or embryonic features that enhance embryonic oxygen availability. We tested the hypotheses that embryos of the oviparous lizard Sceloporus undulatus from a high-latitude population in New Jersey are oviposited at more advanced developmental stages and have a higher growth rate at low oxygen partial pressures ( p O2 ) than embryos from a low-latitude population in South Carolina. These hypotheses were rejected; embryos from the two populations did not differ in embryonic stage at oviposition, survival, rate of differentiation or growth in mass when incubated under simulated in utero conditions at low oxygen concentrations. We also estimated the effective p O2 experienced by lizard embryos in utero . At an effective p O2 of 8.6 kPa (9% O2 ), development of S. undulatus embryos is arrested at Dufaure and Hubert stage 30 and at a dry mass of 0.8 mg. Physiological and morphological features of gravid females, embryos, or both, that facilitate oxygen uptake for developing embryos appear to be a critical early step during the evolution of reptilian viviparity. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 289–299. 相似文献
906.
907.
908.
Development of the capacity for isoprene emission in kudzu 总被引:7,自引:0,他引:7
909.
Cloning and expression of a hypoxic and nitrogen inducible maize alanine aminotransferase gene 总被引:6,自引:1,他引:5
Alanine aminotransferase (ALT, EC 2.6.1.2) is regulated by hypoxia in the roots of several plant species, and by light and nitrogen stress in the leaves of the C4 plant, broomcorn millet ( Panicum miliaceum ). In order to more fully characterize the regulation of ALT, we isolated a maize alt genomic clone that has high sequence homology to the coding regions of both the barley ( Hordeum vulgare ) and P. miliaceum alt cDNA clones. This is the first plant alt gene isolated to date. The alt gene consists of 15 exons, and has regions of the promoter that are similar to the maize Anaerobic Responsive Element, and to the maize 27‐kDa zein promoter. ALT activity increased 2.1‐fold in roots after 96 h of hypoxic stress, but did not increase significantly in either root or leaf tissue when the plant was subjected to anaerobic conditions. Northern analysis of hypoxic root tissue showed an 18‐fold increase in a single alt mRNA band after 8 h of hypoxic stress, followed by a continual decline in mRNA levels. ALT activity and mRNA levels were also found to increase in root tissue after recovery from nitrogen stress but not after salt, cold or heat stress conditions. These interesting patterns of ALT expression in maize roots as a result of exposure to hypoxia and nitrogen stress are discussed. 相似文献
910.