RESUMO
Mangroves create an ecological environment for a diverse assemblage of organisms, including marine and mangrove oomycetes. Halophytophthora spp., in particular, are isolated from fallen senescent mangrove leaves. Studies reported on Philippines oomycetes are mostly on their distribution and taxonomy, while fatty acid studies have not yet been fully explored. Recently, oomycetes were reported as efficient producers of various fatty acids; therefore, bioprospecting efforts are aimed at obtaining more industrially important fatty acid compounds for aquaculture, biodiesel production, and human consumption. In this study, 21 isolated oomycetes, identified as Halophytophthora spp., and two type species of Phytopythium, were grown in a broth medium containing peptone, yeast extract, glucose, and 50% seawater and incubated at room temperature for 3 weeks for fatty acid production and identification. Results revealed the presence of various fatty acids, mainly palmitic acid (C16:0), linoleic acid (C18:2n6c), oleic acid (C18:1n9c), cis-11,14,17-eicosatrienoic acid (ETA, C20:3n3), and stearic acid (C18:0), from Halophytophthora and Phytopythium isolates ranging from 2% to 30% total fatty acids. An omega-6 fatty acid, Ƴ-linolenic acid (GLA, C18:3n6), was found in Phytopythium isolates with considerably higher concentrations compared to Halophytophthoras. Further, omega-3 polyunsaturated fatty acid, cis-11,14,17-eicosatrienoic acid (ETA, C20:3n3), was detected on most oomycete isolates.
Assuntos
Ácidos Graxos , Oomicetos , Humanos , Filipinas , Ácido Linoleico , Ácido Oleico , Ácidos Graxos InsaturadosRESUMO
A novel extremely halophilic archaeon, strain RHB-CT, was isolated from a saturated brine pond of a solar saltern in Bolinao, Pangasinan, Philippines. Colonies were orange-red-pigmented, smooth, convex and round on a solid modified growth medium containing 25â% (w/v) of total salts. Cells of strain RHB-CT on the solid modified growth medium were ovoid-shaped (0.89-2.66 µm long), while the cells in a liquid modified growth medium were rod-shaped (1.53-5.65 µm long and 0.45-1.03 µm wide). The strain was Gram-stain-negative, motile and strictly aerobic. Strain RHB-CT grew with NaCl concentrations ranging from 10 to 30â% (w/v; optimum, 20-25â%), at pH 6.5-8.5 (optimum, pH 7.0-7.5) and at 20-55 °C (optimum, 40-45 °C). Furthermore, the strain grew even in the absence of Mg2+; however, when supplemented with Mg2+, growth was observed optimally at 0.2-0.4 M Mg2+. The 16S rRNA gene phylogeny inferred that the strain is a member of the genus Halorubrum and was related to Halorubrum xinjiangense CGMCC 1.3527T (99.0â%), Halorubrum sodomense DSM 3755T (98.8â%), Halorubrum coriense Ch2T (98.8â%), Halorubrum trapanicum NRC 34021T (98.4â%) and Halorubrum distributum JCM 9100T (98.1â%). The rpoB' gene sequences also showed that strain RHB-CT is related to Hrr. xinjiangense JCM 12388T (97.1â%), Hrr. distributum JCM 9100T (97.1â%), Hrr. coriense JCM 9275T (96.5â%), Hrr. californiense JCM 14715T (96.5â%), Hrr. trapanicum JCM 10477T (96.3%), Hrr. sodomense JCM 8880T (96.2%) and Hrr. tebenquichense DSM 14210T (95.6â%). The DNA G+C content of strain RHB-CT was 68.7 mol% (genome). Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain RHB-CT and the closely related species of Halorubrum were below 40 and 90â%, respectively, which are far below the thresholds to delineate a new species. The polar lipids of strain RHB-CT were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulphate and sulfated mannosyl glycosyl diether. Based on dDDH and ANI values, and the significant morphological and physiological differences from known taxa, it is hereby suggested that strain RHB-CT represents a novel species of the genus Halorubrum, for which the name Halorubrum salinarum sp. nov. is proposed. The type strain is RHB-CT (=KCTC 4274T=CMS 2103T).
Assuntos
Halorubrum , Filogenia , Lagoas/microbiologia , Sais , Composição de Bases , DNA Arqueal/genética , Ácidos Graxos/química , Halorubrum/classificação , Halorubrum/isolamento & purificação , Filipinas , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Marine oomycetes are ubiquitous, fungus-like eukaryotes known to produce fatty acids with potential anticancer activity. The long chain omega-3 and omega-6 fatty acids are currently popular and considered as safe when used as nutraceuticals in cancer treatment. In this study, crude fatty acids from three marine oomycetes, Halophytophthora spp. (T12GP1 and T12YBP2) and Salispina hoi (USTCMS 1611), were explored for their cytotoxic and apoptotic potentials against human breast adenocarcinoma cells (MCF7) and normal human dermal fibroblasts (HDFn). Extracts from mycelia mats consisted of diverse saturated, monounsaturated, and polyunsaturated fatty acids such as linoleic, α-linolenic, γ-linolenic, eicosatrienoic and eicosapentaenoic acids. The crude fatty acids from all three oomycetes in in vitro assays for cytotoxicity showed no toxicity (30% toxicity values) on HDFn cells. On MCF7 cells, however, IC50 values of 23.44, 15.63, and 26.15 µg/mL were obtained with extracts from Halophytophthora T12GP1 and T12YBP2 and S. hoi, respectively. Treated MCF7 cells exhibited deformed cell membrane in MTT assay and also aggregation of DNA and disruption of nuclear membrane aggregation in nuclear staining; further, green signals indicative of apoptosis was recorded in caspase 3/7 assay.
Assuntos
Antineoplásicos/farmacologia , Ácidos Graxos/farmacologia , Oomicetos/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Ácidos Graxos/toxicidade , Fibroblastos/efeitos dos fármacos , Humanos , Células MCF-7 , Membrana Nuclear/efeitos dos fármacos , Membrana Nuclear/metabolismoRESUMO
The genus Salispina was recently described for saprotrophic estuarine oomycetes with aculeolate or spiny sporangia. The genus currently contains three species, S. intermedia, S. lobata, and S. spinosa, the latter two previously included in Halophytophthora. During a survey of mangrove-inhabiting oomycetes in the Philippines, an isolate of Salispina (USTCMS 1611), was obtained from a decaying mangrove leaf. This isolate differed from other species in the genus in a unique combination of morphological and biological characters. Phylogenetic analysis revealed it to be the sister lineage of S. lobata. Consequently, the new species name S. hoi is introduced for the isolate. In addition, Salispina spp. grouped with Sapromyces of Rhipidiales with strong support, but differs from all other known genera of the order in the weak formation of hyphal constrictions, and absence of basal thalli and a holdfast network. The new family Salispinaceae is, therefore, described to accommodate Salispina in the order Rhipidiales.
RESUMO
BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) are common environmental contaminants which are highly toxic due to their carcinogenic and mutagenic effects. They are released into the environment by incomplete combustion of solid and liquid fuels, accidental spillage of oils and seepage from industrial activities. One of the promising processes mitigating PAHs is through biodegradation. However, conventional microbiological treatment processes do not function well at high salt concentrations. Hence, utilization of halophilic bacteria should be considered. OBJECTIVES: This study aimed to assess the ability of halophilic bacteria isolated from local salt beds in Pangasinan and Cavite, the Philippines, to degrade PAHs pyrene, fluorene and fluoranthene. METHODS: Polycyclic aromatic hydrocarbon-tolerant halophilic bacteria collected from two sampling sites were phenotypically characterized, molecularly identified and tested to determine their potential to degrade the PAHs pyrene, fluorene and fluoranthene at a hypersaline condition. Best PAH degraders were then assayed to identify the optimal degradation using such parameters as pH, temperature and PAH concentration. Testing for enzyme degradation was also done to determine their baseline information. Extraction and analysis of degraded PAHs were performed using centrifugation and UV-vis spectrophotometry. RESULTS: Twelve isolates from both collection sites tolerated and grew in culture with selected PAHs. These were identified into four genera (Halobacillus, Halomonas, Chromohalobacter, and Pontibacillus). Selected best isolates in a series of biodegradation assays with the above-mentioned parameters were Halobacillus B (Collection of Microbial Strains (CMS) 1802) (=trueperi) (Gram-positive) for pyrene and fluoranthene, and Halomonas A (CMS 1901) (Gram-negative) for fluorene. Degrader biomass and PAH degradation were invariably negatively correlated. Qualitative tests with and without peptone as a nitrogen source implied enzymatic degradation. DISCUSSION: Polycyclic aromatic hydrocarbons utilized by these halophilic bacteria served as a sole source of carbon and energy. Implications of biodegradation of the two best isolates show that high molecular weight (HMW) (4-ring) pyrene tends to be degraded better by Gram-positive bacteria and low molecular weight (3-ring) fluorene by Gram-negative degraders. CONCLUSIONS: Halophilic bacteria constitute an untapped natural resource for biotechnology in the Philippines. The present study demonstrated their potential use in bioremediation of recalcitrant hydrocarbons in the environment. COMPETING INTERESTS: The authors declare no competing financial interests.
RESUMO
The Salisapilia species are estuarine oomycetes of the mangrove and saltmarsh ecosystem. To date, reports on the secondary metabolites and biological activities of these microorganisms are wanting. In this study, secondary metabolites in broth ethyl acetate extracts (BEAE) and mycelial ethyl acetate extracts (MEAE) of Salisapilia tartarea S1YP1 isolated from yellow senescent mangrove leaves were screened by Thin Layer Chromatography (TLC). Extracts were assayed for antioxidant, antibacterial, α- glucosidase inhibition, and cytotoxic activity. The TLC detected anthraquinones, anthrones, flavonoids, phenols, and triterpenes in both BEAE and MEAE. Coumarins were detected in BEAE but not in MEAE. Quantifying the total phenolics and total flavonoids content of the extracts in terms of gallic acid and quercetin equivalents, respectively shows that BEAE has higher total phenolic and flavonoid contents than MEAE. BEAE exhibited significant antioxidant activities through measurements of free radical scavenging activity against DPPH, hydroxyl, nitric oxide, and superoxide anion radicals as well as the ability to chelate Fe2+ metal ion. BEAE significantly inhibited in a dose-dependent manner α-glucosidase activity and selectively inhibited HepG2 cell proliferation. Antioxidant, α- glucosidase inhibitory, and cytotoxic activities have not been observed for MEAE. Both BEAE and MEAE do not have antibacterial activity.
Assuntos
Avicennia/microbiologia , Produtos Biológicos/farmacologia , Oomicetos/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/toxicidade , Cromatografia em Camada Fina/métodos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/toxicidade , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/toxicidade , Células Hep G2 , Humanos , Oomicetos/isolamento & purificação , Folhas de Planta/microbiologiaRESUMO
BACKGROUND: Discharge of textile dyes into the environment poses a significant threat. They are poorly biodegradable and toxic due to their complex composition and aromatic structures. In the search for alternatives to physical and chemical treatments, biodegradation of synthetic dyes by various microbes is emerging as an effective and promising approach. OBJECTIVES: The decolorization of synthetic dyes by yeast co-cultures and consortia from leaves and fruit peels was assessed at a 50 µg/mL dye concentration. METHODS: Yeasts isolates from leaves and fruit peels were screened for potential decolorization of synthetic dyes at 25-50 µg/mL. Decolorization parameters were optimized for synergistic properties and development of yeast co-cultures and consortium. Possible decolorization reactions were initially assessed by cell immobilization, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and Fourier transform infrared spectroscopy (FTIR) analysis. RESULTS: A total of 16 organisms were isolated from rose, mango, and pineapple leaves and pineapple fruit peels. Only 4 organisms showed high decolorization of four synthetic dyes: Direct Pink B, Disperse Yellow 5G, Direct Fast Orange S, and Reactive Turquoise Blue G. The optimum condition for best decolorizers of selected dyes at 50 µg/mL were Candida guilliermondii (Y011) for Direct Pink B at pH 9, 37°C; C. dubliniensis (Y014) for Disperse Yellow 5G at pH 4, 25°C; C. guilliermondii (Y004) for Direct Fast Orange S at pH 7, 25°C, and C. famata (Y003) for Reactive Turquoise Blue G at pH 4, 35°C. None of the 4 yeast isolates showed any antagonistic activity when subjected to the lawn-spotting method for the formation of co-cultures and consortium. The best co-cultures obtained 61% decolorization of Direct Pink B, 65% decolorization of Disperse Yellow 5G, 41% decolorization of Direct Fast Orange S, and 50-51% decolorization of Reactive Turquoise Blue G. Immobilized yeast cells were active in decolorizing the dyes and SDS-PAGE analysis confirmed the presence of an extracellular protein. The results of FTIR also showed changes in the functional group of Direct Pink B, but minimal changes in the functional groups of Reactive Turquoise Blue G, indicating a different decolorization pathway. CONCLUSIONS: Yeasts in co-cultures and consortia can decolorize toxic synthetic dyes through different decolorization pathways such as enzyme degradation and bioaccumulation. This technique may have a use in the treatment of wastewater systems.