Cycas revoluta

About: Cycas revoluta is a research topic. Over the lifetime, 167 publications have been published within this topic receiving 1882 citations. The topic is also known as: Japanese sago palm & Sago cycas.

Amino acids as sources of nitrogen for orchid embryos

Abstract: of the life cycle of Macrozamia spiralis Miq. Proc. Linn. Soc. N.S. Wales 55: 494-524. CALDWELI,, 0. W. 1907. Microcycas calocoma. Bot. Gaz. 44:11l8-141. CHAiVIBERLAIN, C. J. 1909. Spermatogenesis in Dioon edlule. Bot. Gaz. 47:215--236. 1910. Fertilization and embryogeny of Dioiht edule. Bot. Gaz. 50:415-429. 1916. Stangeria paradoxa. Bot. Gaz. 61:353372. -. 1935. Gymnosperms. Structure and Evolution. Chicago. DOWNIE, D. G. 1928. The male gametophyte of Microcycas calocoma. Bot. Gaz. 85: 437-450. IKENO, S. 1896. Das Spermatozoid von Cycas revoluta. Bot. Mag. Tokyo 10: 367-368. 1897. Vorliufige Mitteilung iiber die Spermatozoiden bei Cycas revoluta. Bot. Centralbl. 69: 1-3. 1898. Untersuchungen uber die Entwicklung der Geschlechtsorgane und den Vorgang der Befruchtung bei Cycas r evoluta. Jahrb. Wiss. Bot. 32: 557-602. MIYAKE, K. 1905. Spermatozoids of Cycas r evoluta. Bot. Mag. Tokyo 19: 1-9. . 1906. tber die Spermatozoiden von Cycas rev&luta. Ber. Deutsch. Bot. Ges. 24: 78-83. PILGER, R. 1926. Gymnospermae. In Engler and Prantl, Die Naturlichen Pflanzenfamilien. 2nd Ed. SEDGWICK, P. J. 1924. The life history of Encephalartos. Bot. Gaz. 77: 300-310. TREUB, M. 1884. Recherches sur les Cycadees. 3. Embryogenie du Cycas ci-cinalis. Ann. Jard. Bot. Bui,tenzorg 4: 1-11. WODEHOUSE, R. P. 1935. Pollen Grains. New York.

Comparative analysis of carbohydrate-binding properties of two tandem repeat-type Jacalin-related lectins, Castanea crenata agglutinin and Cycas revoluta leaf lectin

Abstract: Lectins belonging to the jacalin-related lectin family are distributed widely in the plant kingdom. Recently, two mannose-specific lectins having tandem repeat-type structures were discovered in Castanea crenata (angiosperm) and Cycas revoluta (gymnosperm). The occurrence of such similar molecules in taxonomically less related plants suggests their importance in the plant body. To obtain clues to understand their physiological roles, we performed detailed analysis of their sugar-binding specificity. For this purpose, we compared the dissociation constants (K(d)) of Castanea crenata agglutinin (CCA) and Cycas revoluta leaf lectin (CRLL) by using 102 pyridylaminated and 13 p-nitrophenyl oligosaccharides with a recently developed automated system for frontal affinity chromatography. As a result, we found that the basic carbohydrate-binding properties of CCA and CRLL were similar, but differed in their preference for larger N-linked glycans (e.g. Man7-9 glycans). While the affinity of CCA decreased with an increase in the number of extended alpha1-2 mannose residues, CRLL could recognize these Man7-9 glycans with much enhanced affinity. Notably, both lectins also preserved considerable affinity for mono-antennary, complex type N-linked glycans, though the specificity was much broader for CCA. The information obtained here should be helpful for understanding their functions in vivo as well as for development of useful probes for animal cells. This is the first systematic approach to elucidate the fine specificities of plant lectins by means of high-throughput, automated frontal affinity chromatography.

Leaf carbon management in slow‐growing plants exposed to elevated CO2

Abstract: Two slow-growing plant species (Chamaerops humilis, L. and Cycas revoluta Thunb.) were exposed to elevated CO2 conditions over a 20-month period in order to study the CO2 effect on growth, photosynthetic capacity and leaf carbon (C) management. The ambient isotopic 13C/12C composition (δ13C) of the greenhouse module corresponding to elevated CO2 (800 μmol mol−1 CO2) conditions was changed from δ13C ca. −12.8±0.3‰ to ca. −19.2±0.2‰. Exposure of these plants to elevated CO2 enhanced dry mass (DM) by 82% and 152% in Chamerops and Cycas, respectively, mainly as a consequence of increases in plant level photosynthetic rates. However, analyses of A–Ci curve parameters revealed that elevated CO2 diminished leaf photosynthetic rates of Chamaerops whereas in Cycas, no photosynthetic acclimation was detected. The fact that Chamaerops plants had a lower DM increase, together with a longer leaf C residence time and a diminished capacity to respire recently fixed C, suggests that this species was unable to increase C sink strength. Furthermore, the consequent C source/sink imbalance in Chamaerops might have induced the downregulation of Rubisco. Cycas plants were capable of avoiding photosynthetic downregulation due to a greater ability to increase C sink strength, as was confirmed by DM values, and 12C-enriched CO2 labeling data. Cycas developed the ability to respire a larger proportion of recently fixed C and to reallocate the recently fixed C away from leaves to other plant tissues. These findings suggest that leaf C management is a key factor in the responsiveness of slow-growing plants to future CO2 scenarios.

Seed Morphology in Relation to Dispersal, Evolution, and Propagation of Cycas L.

Abstract: A comparative morphological study of mature seeds of Cycas revoluta, C. media, C normanbyana, C. taiwaniana, and C. wadei revealed a three-layered seed coat consisting of sarcotesta, sclerotesta, and a thin membranous jacket Seeds of C circinalis, C rumphii, and C. thouarsii have an additional layer of spongy tissue, which causes flotation in water. It is speculated that long-distance dispersal of buoyant seeds occurs by the Indian Ocean currents, while nutritionally valuable starch in sarcotesta provides incentive for mammals to affect local dispersal across land Floating seed taxa differ only in minor morphological characters, despite their wide distribution, suggesting a single polymorphic species. Two groups of Cycas may be recognized: the C. revoluta group with relatively small viable seeds that sink in water and float only when inviable, and the C circinalis-rumphii group with large seeds that float regardless of viability.

Phytochemical Investigation of Cycas circinalis and Cycas revoluta Leaflets: Moderately Active Antibacterial Biflavonoids

Abstract: Chemical examination of the methanolic extract of the leaflets of CYCAS CIRCINALIS L. led to the isolation of one new biflavonoid, (2 S, 2'' S)-2,3,2'',3''-tetrahydro-4',4'''-di- O-methylamentoflavone (tetrahydroisoginkgetin; 2), and 15 known compounds, 11 of which are reported for the first time from C. CIRCINALIS. Chromatographic separation of the chloroform extract of C. REVOLUTA Thunb. leaflets afforded 12 compounds, seven of which are reported for the first time from this species. The isolated compounds from both species include 14 biflavonoids, three lignans, three flavan-3-ols, two flavone- C-glucosides, two NOR-isoprenoids, and one flavanone. This is the first report of NMR and CD data of 2,3,2'',3''-tetrahydro-4'- O-methyl- and 2,3-dihydro-4'- O-methyl-amentoflavone ( 6) and ( 7). The effect of O-methylation on the chemical shifts of the neighboring carbons in the (13)C NMR spectra of the dihydro- and tetrahydro-amentoflavone skeletons provides a tool to identify the location of the methoxy groups. Compounds 2, 6, and 18 displayed moderate antibacterial activity against STAPHYLOCOCCUS AUREUS (IC (50) values of 3.9, 9.7, and 8.2 microM, respectively) and methicillin-resistant S. AUREUS (MRSA; IC (50) values of 5.9, 12.5, and 11.5 microM, respectively).