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Chondria

In their study of untrained vs. trained swimmers, Collomp et al.40 suggested that specific training may be the catalyst that stimulates caffeine s ergogenic effects during high intensity, anaerobic activity. The results of many studies have also suggested that only well-trained athletes derive significant benefits from caffeine due to the athletes previously stimulated lipolytic activity and the increased size and density of their mito-chondria.40-52-58-59... [Pg.243]

Not all the cellular DNA is in the nucleus some is found in the mitochondria. In addition, mitochondria contain RNA as well as several enzymes used for protein synthesis. Interestingly, mitochond-rial RNA and DNA bear a closer resemblance to the nucleic acid of bacterial cells than they do to animal cells. For example, the rather small DNA molecule of the mitochondrion is circular and does not form nucleosomes. Its information is contained in approximately 16,500 nucleotides that func-tion in the synthesis of two ribosomal and 22 transfer RNAs (tRNAs). In addition, mitochondrial DNA codes for the synthesis of 13 proteins, all components of the respiratory chain and the oxidative phosphorylation system. Still, mitochondrial DNA does not contain sufficient information for the synthesis of all mitochondrial proteins most are coded by nuclear genes. Most mitochondrial proteins are synthesized in the cytosol from nuclear-derived messenger RNAs (mRNAs) and then transported into the mito-chondria, where they contribute to both the structural and the functional elements of this organelle. Because mitochondria are inherited cytoplasmically, an individual does not necessarily receive mitochondrial nucleic acid equally from each parent. In fact, mito-chondria are inherited maternally. [Pg.220]

In another legume, Afzelia bella Harms (Caesalpinoidene), the same authors have isolated the new rrfree amino acids. The structure of the diacid 54 is based on mass, H, and l3C-NMR spectroscopy (95) the proposed absolute configuration of 54 was also demonstrated by X-ray diffraction (96). Compound 54 is probably identical with the diacid independently isolated from the red alga Chondria coerulescens (Crouan) Falk. (Rhodomelaceae) (97). [Pg.294]

Although isolated in 1959 (125) from the now rare red alga Chondria armata Okamura (Rhodomelaceae), domoic acid (77) was given a tentative structure... [Pg.299]

Daigo K (1959) Constituents of Chondria armata. IV. Determination of domoic acid. Yakuga Zasshi 79 360-364... [Pg.21]

Chondria armata neurotoxic nonprotein amino acids... [Pg.55]

COjH H Red aigae -Chondria armata isodomic acids D-F -insecticidai nonprotein amino acids 230... [Pg.56]

COjH H02C" H Red aigae -Chondria armata and diatom Pseudonitzschia australis isodomic acid C - nonprotein amino acid with insecticidai activity 257, 258... [Pg.56]

Domoic acid (Fig. 28,80) (263) is a neuro-phycotoxin responsible for the mortality of wildlife and for amnesic shellfish poisoning (ASP) of humans during algal bloom. Domoic acid was first isolated from the red alga Chondria armata ( domoi in Japanese), and it is produced also by diatoms, such as Pseudo-nitzschia spp. For the latter, evidence has been presented that it is involved in iron acquisition (307). [Pg.39]

A number of unusual cyclic polysulfides showing antibiotic activity against bacteria and fungi have been isolated from the red alga Chondria aalifomica ( ) and from the mushroom Lentinue edodes ( ). Both 34 (1,2,4,6-tetrathiepane) and 35 (1,2,3,5,6-pentathiepane or lenthionine) have been isolated from both sources, while 1,2,3,4,5,6 -hexathiepane, 36, was obtained from the mushroom and 27 (1,2,4-trithiolane), 2 (1,2,4-trithiolane 4-oxide),... [Pg.12]

Jaspamide (17), previously mentioned in Section 17.3, is a modified peptide isolated from a Jaspis sponge. Jaspamide shows insecticidal activity against Heliothis virescens with an LCS0 of 4 ppm, as compared to 1 ppm for azadirachtin. Jaspamide (17), showed more than 72% mortality at 100 ppm to both southern com rootworm and tobacco budworm. Iso-domoic acids A (40), B, and C are novel amino acids from the red alga Chondria armata. They... [Pg.247]

The structures of nine of these compounds were determined by spectroscopic methods, while those of the 14 remaining materials were established by GC-MS only. The compounds can be classified into four types (A to D) the 1,2,4-trithiolanes (145-154), 1,2,4,5-tetrathianes (155-157), 1,2,3,5,6-pentathiepanes (158-163), which are all generally quite stable compounds, and the monoalkyl-substituted polysulfides (164-167), which tend to disproportionate into sulfur and disubstituted cyclic polysulfides. These compounds are structurally related to the cyclic polysulfide compounds reported from red alga Chondria californica in 1976 [136] and to compound 168 (3-hexyl-4,5-dithiacycloheptanone) reported from the brown algae of the Dictyopteris genus in 1971 [137]. The latter compound has more recently been found to be a potent inhibitor of bee venom-derived phospholipase A2 (PLA2) [138]. [Pg.842]

A few natural products which contain the cyclopropyl ring have been synthesized through metal catalysed cyclopropanation using dicarbonyl diazomethanes. ( )-Cycloeudesmol 63, isolated from marine alga Chondria oppositiclada, was synthesized via a sequence involving a copper catalysed cyclopropanation of a-diazo-/8-ketoester 61 to give the key intermediate 62 (equation 73)1 7,108. Similarly, the bicyclo[3.1.0]hexane derivative 65 was synthesized from the corresponding a-diazo-/8-ketoester 64 via the catalytic method and was converted into ( )-trinoranastreptene 66 (equation 74)109. Intramolecular cyclopropanation of -diazo-/i-ketoesters 67 results in lactones 68 which are precursors to 1-aminocyclopropane-l-carboxylic acids 69 (equation 75)110. [Pg.677]

The sea hare Dolabella auricularia has furnished aurilol (628), which is cytotoxic (728) and for which the structure has now been fully assigned by total synthesis (729). The Indian Ocean red alga Chondria armata, a member of the Laurencia family, contains armatols A-F (629-634) (730). [Pg.89]

Ciavatta ML, Wahidulla S, D Souza L, Scognamiglio G, Cimino G (2001) New Bromotriterpene Polyethers from the Indian Alga Chondria armata. Tetrahedron 57 617... [Pg.411]

The red alga Digenea simplex has been used for the treatment of roundworm disease for centuries. Its active principle is kainic acid. The related domoic acid is a constituent of another red alga, Chondria armata, used for the same purpose. These compounds, known as kainoids, are potent neurotoxins and excitatory amino acids. Kainoids are important tools in neurophysiological research. Domoic acids are also produced by diatoms and were responsible for the shellfish poisonings known as amnesic shellfish poisonings that occurred in Canada in 1987. [Pg.139]

Another anthelmintic folk medicine used in Japan is the red algae Chondria armata belonging to the same family (Rhodomelaceae) with Digenea simplex. However, its use in this purpose has only been known from Tokunoshima, a small island located in the northeast of Okinawa. Its insecticidal property against flies has been noted by the residents of Yakushima, another island farther north. [Pg.141]

Novel indole derivatives continue to be found in marine organisms those reported recently include dendrodoine (3), a cytotoxic thiadiazole derivative, which occurs in the tunicate Dendrodoa grossularia, from Brittany,4 and the keto-lactam (4), one of two lactams isolated from the Caribbean sponge Hali-chondria melanodocia.5... [Pg.145]

Isodomoic acids A-C (140-142) were isolated from aqueous extracts of a Japanese red alga (Chondria armata) they exhibit significant insecticidal... [Pg.61]

Domoic acid 4 (Figure 3) was isolated in 1958 from another Japanese marine alga, Chondria armata.4 Determination of the stereochemistry at C-5 proved problematic until it was confirmed as R by Ohfune in a total synthesis achieved in 1982.5 Structurally related derivatives, isodomoic acids A-F and domoilactones A and B have subsequently been isolated from Chondria armata. [Pg.161]

The Japanese have used extracts from Chondria armata as an insecticide, the active component being (-)-domoic acid 4.27 Insecticidal activity is found to depend on the nature of the kainoid C-4 substituent. [Pg.166]


See other pages where Chondria is mentioned: [Pg.126]    [Pg.127]    [Pg.27]    [Pg.29]    [Pg.300]    [Pg.55]    [Pg.60]    [Pg.60]    [Pg.30]    [Pg.118]    [Pg.102]    [Pg.713]    [Pg.795]    [Pg.193]    [Pg.724]    [Pg.819]    [Pg.249]    [Pg.348]    [Pg.758]    [Pg.79]    [Pg.315]    [Pg.139]    [Pg.33]   
See also in sourсe #XX -- [ Pg.75 , Pg.224 ]

See also in sourсe #XX -- [ Pg.26 , Pg.488 ]

See also in sourсe #XX -- [ Pg.488 ]




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Chondria armata

Chondria armata, domoic acid

Chondria californica

Chondria crassicaulis

Chondria oppositiclada

Chondria oppositiclada cycloeudesmol from

Chondria tenuissima

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