RESUMO
Fucoxanthin is a versatile substance in the food and pharmaceutical industries owing to its excellent antioxidant and anti-obesity properties. Several microalgae, including the haptophyte Pavlova spp., can produce fucoxanthin and are potential industrial fucoxanthin producers, as they lack rigid cell walls, which facilitates fucoxanthin extraction. However, the commercial application of Pavlova spp. is limited owing to insufficient biomass production. In this study, we aimed to develop a mixotrophic cultivation method to increase biomass and fucoxanthin production in Pavlova gyrans OPMS 30543X. The effects of culturing OPMS 30543X with different organic carbon sources, glycerol concentrations, mixed-nutrient conditions, and light intensities on the consumption of organic carbon sources, biomass production, and fucoxanthin accumulation were analyzed. Several organic carbon sources, such as glycerol, glucose, sucrose, and acetate, were examined, revealing that glycerol was well-consumed by the microalgae. Biomass and fucoxanthin production by OPMS 30543X increased in the presence of 10 mM glycerol compared to that observed without glycerol. Metabolomic analysis revealed higher levels of the metabolites related to the glycolytic, Calvin-Benson-Bassham, and tricarboxylic acid cycles under mixotrophic conditions than under autotrophic conditions. Cultures grown under mixotrophic conditions with a light intensity of 100 µmol photons m-2 s-1 produced more fucoxanthin than autotrophic cultures. Notably, the amount of fucoxanthin produced (18.9 mg/L) was the highest reported thus far for Pavlova species. In conclusion, the use of mixotrophic culture is a promising strategy for increasing fucoxanthin production in Pavlova species. KEY POINTS: ⢠Glycerol enhances biomass and fucoxanthin production in Pavlova gyrans ⢠Metabolite levels increase under mixotrophic conditions ⢠Mixotrophic conditions and medium-light intensity are appropriate for P. gyrans.
Assuntos
Biomassa , Glicerol , Haptófitas , Xantofilas , Xantofilas/metabolismo , Glicerol/metabolismo , Haptófitas/metabolismo , Haptófitas/crescimento & desenvolvimento , Haptófitas/efeitos da radiação , Microalgas/metabolismo , Microalgas/crescimento & desenvolvimento , Meios de Cultura/química , Carbono/metabolismo , Luz , MetabolômicaRESUMO
Mycobacterium avium complex (MAC) is a serious disease that is mainly caused by infection with the non-tuberculous mycobacteria (NTM), Mycobacterium avium and Mycobacterium intracellulare. Seven new compounds, designated mavintramycins A-G (1-7), were isolated along with structurally related compounds, including amicetin (9) and plicacetin (10), from the culture broth of Streptomyces sp. OPMA40551 as anti-MAC compounds that were active against M. avium and M. intracellulare. Among them, mavintramycin A showed the most potent and selective inhibition of M. avium and M. intracellulare. Furthermore, mavintramycin A was active against more than 40 clinically isolated M. avium, including multidrug-resistant strains, and inhibited the growth of M. avium in a persistent infection cell model using THP-1 macrophages. Mavintramycin A also exhibited in vivo efficacy in silkworm and mouse infection assays with NTM. An experiment to elucidate its mechanism of action revealed that mavintramycin A inhibits protein synthesis by binding to 23S ribosomal RNA in NTM. Mavintramycin A, with a different chemical structure from those of clinically used agents, is a promising drug candidate for the treatment of MAC infectious disease.
Assuntos
Doenças Transmissíveis , Infecção por Mycobacterium avium-intracellulare , Animais , Camundongos , Complexo Mycobacterium avium , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Infecção por Mycobacterium avium-intracellulare/microbiologia , Mycobacterium aviumRESUMO
The natural pigment fucoxanthin has attracted global attention because of its superior antioxidant properties. The haptophyte marine microalgae Pavlova spp. are assumed to be promising industrial fucoxanthin producers as their lack of a cell wall could facilitate the commercialization of cultured cells as a whole food. This study screened promising Pavlova strains with high fucoxanthin content to develop an outdoor cultivation method for fucoxanthin production. Initial laboratory investigations of P. pinguis NBRC 102807, P. lutheri NBRC 102808, and Pavlova sp. OPMS 30543 identified OPMS 30543 as having the highest fucoxanthin content. The culture conditions were optimized for OPMS 30543. Compared with f/2 and Walne's media, the use of Daigo's IMK medium led to the highest biomass production and highest fucoxanthin accumulation. The presence of seawater elements in Daigo's IMK medium was necessary for the growth of OPMS 30543. OPMS 30543 was then cultured outdoors using acrylic pipe photobioreactors, a plastic bag, an open tank, and a raceway pond. Acrylic pipe photobioreactors with small diameters enabled the highest biomass production. Using an acrylic pipe photobioreactor with 60-mm diameter, a fucoxanthin productivity of 4.88 mg/L/day was achieved in outdoor cultivation. Thus, this study demonstrated the usefulness of Pavlova sp. OPMS 30543 for fucoxanthin production in outdoor cultivation.
Assuntos
Haptófitas/química , Haptófitas/crescimento & desenvolvimento , Xantofilas/metabolismo , Biomassa , Meios de Cultura , FotobiorreatoresRESUMO
Among four mycobacteria, Mycobacterium avium, M. intracellulare, M. bovis BCG and Mycobacteroides (My.) abscessus, we established a silkworm infection assay with My. abscessus. When silkworms (fifth-instar larvae, n = 5) were infected through the hemolymph with My. abscessus (7.5 × 107 CFU/larva) and bred at 37 °C, they all died around 40 h after injection. Under the conditions, clarithromycin and amikacin, clinically used antimicrobial agents, exhibited therapeutic effects in a dose-dependent manner. Furthermore, five kinds of microbial compounds, lariatin A, nosiheptide, ohmyungsamycins A and B, quinomycin and steffimycin, screened in an in vitro assay to observe anti-My. abscessus activity from 400 microbial products were evaluated in this silkworm infection assay. Lariatin A and nosiheptide exhibited therapeutic efficacy. The silkworm infection model with My. abscessus is useful to screen for therapeutically effective anti-My. abscessus antibiotics.
Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Mycobacterium abscessus/fisiologia , Animais , Bombyx , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Mycobacterium abscessus/efeitos dos fármacosRESUMO
A new cytotoxic agent designated as 2-epi-anthracimycin (1) was isolated along with anthracimycin and anthracimycin B (2-demethylanthracimycin) from the culture broth of the marine-derived actinomycete Streptomyces sp. OPMA00631. The structure of 1 was elucidated based on spectroscopic analyses (1D and 2D NMR data and ROESY correlations). Compound 1 exhibited cytotoxicity against Jurkat cells with an IC50 value of 50.5 µM in 20 h. The effect of 1 on the cell cycle distribution of Jurkat cells was investigated. Compound 1 (7.80 µM) increased G1 phase cells from 51.1 to 62.0% and conversely, decreased G2 and M phase cells from 30.7 to 19.3 % in 20 h. At a higher concentration, 1 (250 µM) markedly increased subG1 phase cells (1.9% at 0 h to 16.5% at 20 h), while the proportion of G1 phase cells was maintained (62.3%). These results suggest that 1 exhibits cytotoxicity against Jurkat cells by arresting the cell cycle at the G1 phase.
Assuntos
Actinobacteria/química , Organismos Aquáticos/química , Citotoxinas/química , Citotoxinas/farmacologia , Policetídeos/química , Policetídeos/farmacologia , Streptomyces/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Células JurkatRESUMO
The marine actinomycete strain OPMA02852, identified as the genus Streptomyces, was found to produce anti-mycobacterial compounds against Mycobacterium avium complex (MAC). One new compound, designated as steffimycin E (1), was isolated together with three known steffimycins (steffimycin (2), 10-dihydrosteffimycin (3), and 8-demethoxysteffimycin (4)) from the culture broth of this producing microorganism by solvent extraction, ODS column chromatography, and preparative HPLC. Compound 1 has a tetracyclic quinone structure with a sugar moiety. Compound 1 exhibited anti-mycobacterial activity against M. intracellulare, M. bovis BCG, and M. smegmatis.
Assuntos
Antraciclinas/farmacologia , Antituberculosos/farmacologia , Complexo Mycobacterium avium/efeitos dos fármacos , Mycobacterium avium/efeitos dos fármacos , Streptomyces/química , Antraciclinas/química , Antituberculosos/química , Linhagem Celular Tumoral , Células HeLa , Humanos , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológicoRESUMO
On our quest for new bioactive molecules from marine sources, two cyclic imines (1, 2) were isolated from a dinoflagellate extract, inhibiting the growth of the respiratory syncytial virus (RSV). Compound 1 was identified as a known molecule portimine, while 2 was elucidated to be a new cyclic imine, named kabirimine. The absolute stereochemistry of 1 was determined by crystallographic work and chiral derivatization, whereas the structure of 2 was elucidated by means of spectroscopic analysis and computational study on all the possible isomers. Compound 1 showed potent cytotoxicity (CC50 < 0.097 µM) against HEp2 cells, while 2 exhibited moderate antiviral activity against RSV with IC50 = 4.20 µM (95% CI 3.31-5.33).
Assuntos
Dinoflagellida/química , Iminas/química , Antivirais/química , Antivirais/farmacologia , Organismos Aquáticos/química , Linhagem Celular Tumoral , Humanos , Iminas/farmacologia , Vírus Sinciciais Respiratórios/efeitos dos fármacosRESUMO
Mycobacterium avium complex (MAC) is a serious disease mainly caused by M. avium and M. intracellulare. Although the incidence of MAC infection is increasing worldwide, only a few agents are clinically used, and their therapeutic effects are limited. Therefore, new anti-MAC agents are needed. Approximately 6600 microbial samples were screened for new anti-mycobacterial agents that inhibit the growth of both M. avium and M. intracellulare, and two culture broths derived from marine actinomycete strains OPMA1245 and OPMA1730 had strong activity. Nosiheptide (1) was isolated from the culture broth of OPMA1245, and griseoviridin (2) and etamycin (viridogrisein) (3) were isolated from the culture broth of OPMA1730. They had potent anti-mycobacterial activity against M. avium and M. intracellulare with minimum inhibitory concentrations (MICs) between 0.024 and 1.56 µg/mL. In addition, a combination of 2 and 3 markedly enhanced the anti-mycobacterial activity against both M. avium and M. intracellulare. Furthermore, a combination 2 and 3 had a therapeutic effect comparable to that of ethambutol in a silkworm infection assay with M. smegmatis.
Assuntos
Antibacterianos/farmacologia , Macrolídeos/farmacologia , Complexo Mycobacterium avium/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Antibacterianos/química , Bombyx/microbiologia , Descoberta de Drogas , Macrolídeos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Infecção por Mycobacterium avium-intracellulare/microbiologia , Infecção por Mycobacterium avium-intracellulare/mortalidade , Peptídeos/química , Tiazóis/química , Tiazóis/farmacologiaRESUMO
A new macrolide named acidiscalide (2), and a known protein synthesis inhibitor, cycloheximide (1), were isolated from the culture broth of a strain of actinomycete, Streptomyces acidiscabies, coded SCTA0002 collected from the coast of Okinawa. The structure of acidiscalide (2) was elucidated to be a glycosylated macrolide having a 24-membered ring on the basis of spectroscopic analysis. Although the stereochemistry could not be determined due to decomposition in the course of the study, it was confirmed that acidiscalide (2) possessed a new molecular scaffold.
Assuntos
Macrolídeos/química , Macrolídeos/metabolismo , Streptomyces/metabolismo , Estrutura Molecular , Oceanos e Mares , Streptomyces/química , Streptomyces/classificação , Microbiologia da ÁguaRESUMO
Eight new thiodiketopiperazines, designated as graphiumins A to H (1-8), were isolated along with bisdethiobis(methylthio)-deacetylaranotin (9) and bisdethiobis(methylthio)-deacetylapoaranotin (10) from the culture broth of the marine-derived fungus Graphium sp. OPMF00224. The structures of the graphiumins were elucidated based on spectroscopic analyses (1D and 2D NMR data, ROESY correlations and CD data) and chemical methods. The absolute configuration of the common (3S)-3-hydroxy-octanoyl acid residue in 1, 3 and 4 was determined by hydrolysis, benzoyl derivatization and HPLC analysis using a chiral column. Five graphiumins moderately inhibited yellow pigment production by methicillin-resistant Staphylococcus aureus.
Assuntos
Antibacterianos/farmacologia , Ascomicetos/química , Piperazinas/farmacologia , Compostos de Sulfidrila/farmacologia , Antibacterianos/isolamento & purificação , Fermentação , Hidrólise , Espectroscopia de Ressonância Magnética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Piperazinas/química , Água do Mar/microbiologia , Espectrometria de Massas por Ionização por Electrospray , Compostos de Sulfidrila/química , Microbiologia da ÁguaRESUMO
Marine-derived Streptomyces sp. OPMA00072 was found to produce inhibitors of the synthesis of neutral lipids in a cell-based assay using Chinese hamster ovary (CHO) cells. A new 16-membered macrolide named bafilomycin L (BFL) (1) was isolated along with the known structurally related bafilomycin C1 (BFC1) (3) from the culture broth of the actinomycete by solvent extraction, octadecylsilyl column chromatography and HPLC. BFL inhibited cholesteryl ester (CE) synthesis in CHO cells with an IC50 value of 0.83 nM and also in mouse peritoneal macrophages with an IC50 of 6.1 nM. In addition, BFL blocked cellular acidification in HeLa cells by interfering with vacuolar H(+)-ATPase (V-ATPase) as well as other bafilomycins. These data strongly suggest that BFL disturbed the lysosome function to block cholesterol metabolism, leading to the inhibition of CE accumulation in mammalian cells.
Assuntos
Ésteres do Colesterol/antagonistas & inibidores , Macrolídeos/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Streptomyces/metabolismo , ATPases Vacuolares Próton-Translocadoras/efeitos dos fármacos , Animais , Células CHO , Colesterol/metabolismo , Ésteres do Colesterol/biossíntese , Cromatografia Líquida de Alta Pressão , Cricetinae , Cricetulus , Células HeLa , Humanos , Concentração Inibidora 50 , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Macrolídeos/administração & dosagem , Macrolídeos/isolamento & purificação , Macrófagos Peritoneais/metabolismo , Camundongos , ATPases Vacuolares Próton-Translocadoras/metabolismoAssuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Aspergillus/metabolismo , Sesterterpenos/farmacologia , Antibacterianos/química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Estrutura Molecular , Saccharomyces cerevisiae/efeitos dos fármacos , Sesterterpenos/química , Sesterterpenos/metabolismoRESUMO
Using B16 melanoma cells for screening, we found that a marine sponge extract has a potent anti-pigmenting effect and identified arenarol as its major active compound. In normal human melanocytes (NHMs), arenarol significantly abrogated the endothelin 1 (EDN1) stimulated expression of tyrosinase, tyrosinase-related protein 1 and dopachrome tautomerase at the transcriptional, translational and enzymatic activity (only for tyrosinase) levels. That effect was accompanied by the attenuation of the increased expression level of microphthalmia-associated transcription factor (MITF) protein at the transcriptional and translational levels. Analysis of EDN1 signaling demonstrated that arenarol significantly suppressed the EDN1-induced phosphorylation of MEK, ERK, MITF and CREB but not of Raf-1s. In contrast, the forskolin-induced phosphorylation of CREB was not down-regulated by arenarol. As for the mode of action of the suppressed phosphorylation of MEK, Raf-1 activity was not directly inhibited by arenarol in vitro and pretreatment with the protein phosphatase inhibitor okadaic acid did not affect the down-regulated phosphorylation of MEK that was induced by arenarol in NHMs. The sum of these findings suggests that arenarol abrogates the EDN1-stimulated expression of melanocyte-specific proteins by interrupting MEK phosphorylation in an as yet unknown Raf-1 inactivation mechanism.
RESUMO
A library of extracts established from hundreds of marine organisms was screened by a cytotoxicity test. The active organic extract of an Okinawan marine sponge of the genus Dysidea was subjected to bioassay-guided fractionation to give three new polyoxygenated steroids dysideasterols F-H (1-3), together with two known related compounds (4 and 5). Their structures were confirmed by NMR and mass spectroscopic analyses. A characteristic structural feature of 2, 4 and 5 is an allylic epoxide, whereas this epoxide undergoes ring-opening by a neighbouring hydroxyl group to give a tetrahydrofuran ring in 1 and 3. All compounds 1-5 exhibited a similar cytotoxic effect with IC50 values of 0.15-0.3 µM against human epidermoid carcinoma A431 cells, demonstrating that the allylic epoxide moiety was not responsible for this cytotoxic effect.
Assuntos
Antineoplásicos/isolamento & purificação , Organismos Aquáticos/química , Dysidea/química , Esteróis/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Japão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Esteróis/química , Esteróis/farmacologiaRESUMO
A new 10-membered-ring diterpene, cyclolobatriene (1), along with three other known diterpenes, lobatriene (2), eunicol (3), and fuscol (4), were isolated from the Okinawan soft coral Lobophytum pauciflorum. Their structures were established by extensive NMR spectroscopic analyses. Cyclolobatriene (1) is an additional example of rare prenylated germacrenes. Although 1, due to a 10-membered-ring structure, exists as an equilibrium mixture of three conformers, the NMR measurement in CDCl(3) at 7°C enabled us to assign the NMR signals of the three, which is the first example of the complete NMR assignment of all the existing conformers of germacrene-type compounds. Cyclolobatriene (1) was thermally unstable and converted into 2 through Cope rearrangement upon heating at 70°C. Eunicol (3) also possesses the same prenylated germacrene structure as 1, showing similar physico-chemical properties to 1. All four compounds 1-4 showed cytotoxic effect with IC(50)'s of 0.64, 0.41, 0.35 and 0.52 µM, respectively, against human epidermoid carcinoma A431 cells.
Assuntos
Antozoários/química , Diterpenos/química , Animais , Linhagem Celular Tumoral , Diterpenos/isolamento & purificação , Diterpenos/toxicidade , Humanos , Espectroscopia de Ressonância Magnética , Conformação MolecularAssuntos
Antineoplásicos/química , Toxinas Marinhas/química , Poríferos/química , Tirosina/análogos & derivados , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Colorimetria , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Toxinas Marinhas/isolamento & purificação , Toxinas Marinhas/farmacologia , Conformação Molecular , Peso Molecular , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Tirosina/química , Tirosina/isolamento & purificação , Tirosina/farmacologiaRESUMO
We examined the biological activities present in Streptomyces strains preserved at the National Institute of Technology and Evaluation Biological Resource Center, and found a metabolite of Streptomyces roseolilacinus NBRC 12815 that showed a potent anti-tyrosinase activity. The compounds with anti-tyrosinase activity were purified by several chromatographic procedures. Final HPLC analysis revealed at least two anti-tyrosinase compounds with different retention times (12815A and B). The identification of two anti-tyrosinase compounds was performed with instrumental analysis and database search. The results obtained suggest that the active compounds are SF 2583A and B. Compound 12815A (IC(50) values; about 9 microM) showed more potent tyrosinase inhibition than compound 12815B (IC(50) values; about 1086 microM). The only structural difference between 12815A and B is the presence of an additional chloric atom. In addition, the activity of 12815A was markedly decreased under acidic conditions, resulting in irreversible inactivation. However, the inactivated 12815A still exhibited residual activity when exposed to detergent, Tween 80. These results suggest that the chlorine and the hydration water are very important in the exertion of anti-tyrosinase activity by 12815A.