RESUMEN
The red algal genus Portieria is a prolific producer of halogenated monoterpenoids. In this study, we isolated and characterised monoterpenoids from the Okinawan red algae Portieria hornemannii. A new polyhalogenated cyclic monoterpenoid, 2(R)-chloro-1,6(S)-dibromo-3(8)(Z)-ochtoden-4(R)-ol (1), along with three known monoterpenoids, (2R,3(8)E,4S,6R)-6-bromo-2-chloro-1,4-oxido-3(8)-ochtodene (2), 1-bromo-2-chloroochtoda-3(8),5-dien-4-one (3), and 2-chloro-1-hydroxyochtoda-3(8),5-dien-4-one (4) were isolated from the methanol extract of three populations of P. hornemannii. These compounds were characterised using a combination of spectroscopic methods and chemical synthesis, and the absolute stereochemistry of compounds 1 and 2 was determined. In addition, all isolated compounds were screened for their anti-biofouling activity against the mussel Mytilus galloprovincialis, and 1 exhibited strong activity. Therefore, halogenated monoterpenoids have the potential to be used as natural anti-biofouling drugs.
Asunto(s)
Incrustaciones Biológicas , Monoterpenos , Rhodophyta , Animales , Incrustaciones Biológicas/prevención & control , Halogenación , Estructura Molecular , Monoterpenos/aislamiento & purificación , Monoterpenos/química , Monoterpenos/farmacología , Rhodophyta/química , Guanetidina/química , Guanetidina/aislamiento & purificación , Guanetidina/farmacologíaRESUMEN
The marine red algal genus Laurencia has abundant halogenated secondary metabolites, which exhibit novel structural types and possess various unique biological potentials, including antifouling activity. In this study, we report the isolation, structure elucidation, and antifouling activities of two novel brominated diterpenoids, aplysin-20 aldehyde (1), 13-dehydroxyisoaplysin-20 (2), and its congeners. We screened marine red alga Laurencia venusta Yamada for their antifouling activity against the mussel Mytilus galloprovincialis. Ethyl acetate extracts of L. venusta from Hiroshima and Chiba, Japan, were isolated and purified, and the compound structures were identified using 1D and 2D NMR, HR-APCI-MS, IR, and chemical synthesis. Seven secondary metabolites were identified, and their antifouling activities were evaluated. Compounds 1, 2, and aplysin-20 (3) exhibited strong activities against M. galloprovincialis. Therefore, these compounds can be explored as natural antifouling drugs.
Asunto(s)
Incrustaciones Biológicas , Diterpenos , Laurencia , Rhodophyta , Incrustaciones Biológicas/prevención & control , Diterpenos/farmacología , Diterpenos/química , Laurencia/química , Estructura Molecular , Rhodophyta/químicaRESUMEN
A new irieane-type diterpene, 12-hydroxypinnaterpene C (1), and 21 known compounds, angasiol acetate (2), angasiol (3), 11-deacetylpinnaterpene C (4), palisadin A (5), 12-acetoxypalisadin B (6), 12-hydroxypalisadin B (7), aplysistatin (8), luzodiol (9), 5-acetoxy-2-bromo-3-chloro-chamigra-7(14),9-dien-8-one (10), neoirietriol (11), neoirietetraol (12), (3Z)-laurenyne (13), cupalaurenol (14), cupalaurenol acetate (15), (3Z)-venustinene (16), 10-hydroxykahukuene B (17), aplysiol B (18), (3Z)-13-epipinnatifidenyne (19), 3Z,6R,7R,12S,13S-obtusenyne (20), (3Z,9Z)-7-chloro-6-hydroxy-12-oxo-pentadeca-3,9-dien-1-yne (21), and cholest-7-en-3,5,7-triol (22) were isolated from the digestive diverticula of Aplysia argus from the Ikei Island in Okinawa, Japan. The structures of these compounds were determined using spectroscopic methods such as NMR and HR-ESI-MS. These compounds were tested for their antibacterial activity against the phytopathogen Ralstonia solanacearum. Compounds 11 and 21 exhibited antibacterial activity at 30â µg/disc. In this study, we also discuss the types of red algae that A. argus feeds on in the shallow waters of Okinawa Prefecture.
Asunto(s)
Aplysia , Rhodophyta , Animales , Antibacterianos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Rhodophyta/química , DiterpenosRESUMEN
Two new eremophilane-type sesquiterpenoids, fusumaols A (1) and B (2), were isolated from the stem-leafy liverwort, Bazzania japonica collected in Mori-Machi, Shizuoka, Japan. Their structures were established using extensive spectroscopic (IR, MS, and 2D NMR) data, and the absolute configuration of 1 was determined by the modified Mosher's method. This is the first time eremophilanes have been discovered in the liverwort genus Bazzania. Compounds 1 and 2 were evaluated for their repellent activity against the adult population of the rice weevil Sitophilus zeamais using the modified filter paper impregnation method. Both sesquiterpenoids showed moderate repellent activities.
Asunto(s)
Hepatophyta , Sesquiterpenos , Hepatophyta/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Sesquiterpenos Policíclicos , Sesquiterpenos/farmacología , Sesquiterpenos/químicaRESUMEN
AIMS: Chronic fatigue syndrome patients often have comorbid psychiatric disorders such as major depressive disorders and anxiety disorders. However, the outcomes of chronic fatigue syndrome and the comorbid psychiatric disorders and the interactions between them are unknown. Therefore, a two-year prospective follow-up study was carried out on chronic fatigue syndrome patients with comorbid psychiatric disorders. METHODS: A total of 155 patients who met the Japanese case definition of chronic fatigue syndrome were enrolled in this study. Comorbid psychiatric disorders were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders 4th edition criteria. Patients with comorbid psychiatric disorders received psychiatric treatment in addition to medical therapy for chronic fatigue syndrome. Seventy patients participated in a follow-up interview approximately 24 months later. RESULTS: Of the 70 patients with chronic fatigue syndrome, 33 patients were diagnosed as having comorbid psychiatric disorders including 18 major depressive disorders. Sixteen patients with psychiatric disorders and eight patients with major depressive disorders did not fulfill the criteria of any psychiatric disorders at the follow up. As for chronic fatigue syndrome, nine out of the 70 patients had recovered at the follow up. There is no significant influence of comorbid psychiatric disorders on the outcome of chronic fatigue syndrome. CONCLUSIONS: Chronic fatigue syndrome patients have a relatively high prevalence of comorbid psychiatric disorders, especially major depressive disorders. The outcomes of chronic fatigue syndrome and psychiatric disorders are independent. Therefore treatment of comorbid psychiatric disorders is necessary in addition to the medical treatment given for chronic fatigue syndrome.