Monodictys Pelagica Research Articles

Antifouling activity of novel polyisoprene-based coatings made from photocurable natural rubber derived oligomers

Natural rubber is a renewable resource with a potential as precursor of a very wide range of novel polymers, including polyisoprene-based surfaces with antifouling (AF) activity. In this work, new ionic and non-ionic coatings were prepared by the photocrosslinking reaction of photosensitive cis-1,4-oligoisoprenes, bearing a variable number of ammonium groups. The photochemical crosslinking was achieved using radical (via acrylate groups) or cationic (via epoxy groups) processes. Surface properties of these coatings were studied by static contact angle measurements and AFM imaging. Assessment of bioactivity demonstrated that most of the resulting coatings showed AF potential against fouling organisms: growth inhibition of marine bacteria (Pseudoalteromonas elyakovii, Shewanella putrefaciens, Cobetia marina, Polaribacter irgensii, Vibrio aestuarianus) and fungi (Halosphaeriopsis mediosetigera, Asteromyces cruciatus, Lulworthia uniseptata, Zalerion sp., Monodictys pelagica); decreased adhesion of microalgae (Navicula jeffreyi, Cylindrotheca closterium, Chlorarachnion globosum, Pleurochrysis roscoffensis, Exanthemachrysis gayraliae, Amphora coffeaeformis); inhibition of attachment and/or germination of spores of Ulva intestinalis. The best AF activity was obtained with the ionic surfaces. These new coatings prepared from precursors obtained from natural rubber are in essence active by contact. As the biocidal functions are fixed covalently to the polymer chain, detectable release of biocidal products in the marine ecosystem is prevented so that a valuable environment-friendly alternative for new AF coatings is hereby proposed.

Evaluation of the Activity of the Sponge Metabolites Avarol and Avarone and their Synthetic Derivatives Against Fouling Micro- and Macroorganisms

The sesquiterpene hydroquinone avarol (1) was isolated from the marine sponge Dysidea avara, whereas the corresponding quinone, avarone (2), was obtained by oxidation of avarol, and the significantly more lipophilic compounds [3'-(p-chloro-phenyl)avarone (3), 3',4'-ethylenedithioavarone (4), 4'-isopropylthioavarone (5), 4'-tert-butylthioavarone (6), 4'-propylthioavarone (7), 4'-octylthioavarone (8)] were obtained by nucleophilic addition of thiols or p-chloroaniline to avarone. All these compounds were tested, at concentrations ranging from 0.5 to 50 microg/mL, for their effect on the settlement of the cyprid stage of Balanus amphitrite, for toxicity to both nauplii and cyprids and for their growth inhibitory activity on marine bacteria (Cobetia marina, Marinobacterium stanieri, Vibrio fischeri and Pseudoalteromonas haloplanktis) and marine fungi (Halosphaeriopsis mediosetigera, Asteromyces cruciatus, Lulworthia uniseptata and Monodictys pelagica).

Lead and cadmium uptake in the marine fungi Corollospora lacera and Monodictys pelagica

This study provides observations on the effects of lead and cadmium ions on the growth of two species of marine fungi, Corollospora lacera and Monodictys pelagica. On solid media lead appeared to have no effect on the radial rate of growth of fungi. Exposure to increasing cadmium concentrations on solid media resulted in significant reduction ( p < 0.05) in the radial mycelial growth rates of both fungi, especially in M. pelagica. These results reveal significant difference in species sensitivity toward cadmium and, essentially, insensitivity toward lead exposure. In liquid cultures, the metal content of mycelia (metal mass found in mycelium, in mg), and the concentration of metal in dry mycelium (metal mass in 1 g of mycelium, in mg g −1) were both found to increase ( p < 0.05) with the increase in the metal cation concentration, while mycelium dry mass decreased. As it was observed on solid media, cadmium cation affected more severely ( p < 0.05) the growth of M. pelagica in liquid cultures. Ergosterol content of mycelia of C. lacera exposed to increasing cadmium cation concentration decreased, similarly to the trend observed for dry mycelial mass. It was found that ca. 93% of all lead sequestered by C. lacera is located extracellularly. M. pelagica was found to bioaccumulate over 60 mg of cadmium and over 6 mg of lead per 1 g of mycelium, while C. lacera bioaccumulated over 7 mg of cadmium and up to 250 mg of lead per 1 g of mycelium. Overall, the results indicate that both metal ions affect the growth of marine fungi with lead being accumulated extracellularly in the mycelia. Both metals accumulated by fungi may then enter the marine ecosystem food web, of which marine fungi are integral members.

Isolation of sterols from the marine fungusCorollospora lacera

Several marine fungi collected from the waters of Prince Edward Island, Canada, were screened for the presence of natural products exhibiting antibacterial activity. Both broths and mycelia of these fungi were studied using the bioassay-guided chromatographic separation. The 4 fractions from the extract of mycelia of Corollospora lacera exhibited weak antibacterial activity and were analyzed further. From these fractions, 2 sterols (5 alpha,8 alpha-epidioxyergosterol and 22E,24R-ergosta-7,22-diene-3beta,5 alpha,6 beta-triol) and a 3:1 mixture of linoleic and oleic acids were isolated. The presence of ergosterol was confirmed in dichloromethane extracts of mycelia of every fungus in this study and this sterol was isolated from the extract of mycelium of Corollospora lacera. Two other known compounds (5-hydroxymethylfuran-2-carbaldehyde and bis(2-ethylhexyl) phthalate), were isolated from the dichloromethane extract of mycelium of Monodictys pelagica. The phthalate was reported in the literature as a metabolite isolated from the fungi, but in our study it was proven to be an artifact of the culturing and (or) extraction procedures rather than a true fungal metabolite.

Temperature Requirements of Selected Marine Fungi

The growth responses of nineteen marine fungi to temperature (10, 20, 30°) and selected media were studied. Poor growth was recorded at 10°C on all media. Growth was greatest at 20°C and 30°C on all media, with the exception of Amylocarpus encephaloides and Marinospora calyptrata with no growth at 30°C. for growth was 20°C for nine fungi (eleven strains) [Ceriosporopsis halima, Marinospora calyptrata encephaloides, Lulworthia sp., Asteromyces cruciatus, Dendryphiella arenaria, Monodictys pelagica (2 strains), Nia vibrissa (2 strains), Digitatispora marina] and 30°C for seven fungi (eight strains) [Corollospora maritima (2 strains), Halosphaeriopsis mediosetigera, Zalerion maritimum, Periconia prolifica, Hydronectria tethys, Hypoxylon oceanicum, Nais glitra]. Slight difference in growth was recorded on the four media employed with increased growth on sea water corn meal agar and sea water starch yeast extract glucose agar

Biodeterioration of woods by marine fungi and Chaetomium globosum in response to an external nitrogen source

The effect of different nitrogen sources on decay of beech and Scots pine by the marine fungi Monodictys pelagica and Zalerion maritimum and by Chaetomium globosum was studied using vermiculite burial and wood block weight loss estimation techniques. The addition of a nitrogen source significantly increased decay of beech by C. globosum and M. pelagica; the highest weight losses of beech were produced by C. globosum (28·3%) and M. pelagica (28·2%) with potassium nitrate. Generally the addition of a nitrogen source did not significantly increase the decay of Scots pine by the three fungi. Zalerion maritimum produced negligible (<4%) weight losses of both woods in all media.

Monodictys pelagica, the anamorph of Nereiospora cristata (Halosphaeriaceae)

Single-ascospore isolates of Nereiospora cristata gave rise to conidia of Monodictys pelagica. Repeated isolations confirmed that M. pelagica was the anamorph of N. cristata. These findings are discussed and compared with the other known anamorph–teleomorph stages of marine fungi, especially the anamorph stages of Corollospora and Nereiospora.

Decomposition of14C-Labeled Maple and Spruce Lignin by Marine Fungi

Fungi occur on driftwood, intertidal wood, manila rope, and other lignocellulosic substrates in marine and estuarine environments (Johnson and Sparrow, 1961; Hughes, 1975; Kohlmeyer and Kohlmeyer, 1979). Several Ascomycetes and Deuteromycetes cause soft rots of wood submerged in seawater (Barghoorn and Linder, 1944; Henningsson, 1976). The marine basidiomycete Nia vibrissa Moore & Meyers causes a white rot (Leightley and Eaton, 1979). Relatively few fungi can decompose lignin, an extremely complex aromatic polymer (Crawford and Crawford, 1980; Crawford, 1981). Fukuzumi et al. (1975) demonstrated that the marine hyphomycete Dendryphiella salina (Sutherland) Pugh & Nicot could degrade sodium lignosulfonate, an industrially modified lignin. Henningsson (1976), using sulfuric acid hydrolysis to measure lignin content, found a strain of Zalerion maritimum (Linder) Anastasiou that degraded 12% of the lignin in birch wood in six months. Methods involving the use of 14C-labeled lignocellulosic substrates have made it possible to determine the amounts of lignin degraded by microorganisms to CO2 and water-soluble products (Crawford and Crawford, 1976). Using [lignin'4C]-lignocelluloses prepared from Norway maple and blue spruce as substrates, we measured the degradation of hardwood and softwood lignin by pure cultures of 12 marine and estuarine fungi. The fungi tested were Asteromyces cruciatus Moreau & Moreau ex Hennebert (F-156), Ceriosporopsis halima Linder (R-592), Corollospora maritima Werdermann (R-19), Dendryphiella salina (DS-1), Diplodia oraemaris Linder (F-162), Halosphaeria mediosetigera Cribb & Cribb (R-575), Heleococcum japonense Tubaki (R-692), Humicola alopallonella Meyers & Moore (F-164), Monodictys pelagica (Johnson) Jones (F-80), Nia vibrissa (RDB-8), Papulaspora halima Anastasiou (F-167), and Zalerion maritimum (R-6). Twigs of Norway maple (Acer platanoides L.) and blue spruce (Picea pungens Engelm.) were incubated with a solution of L-[U-14C]-phenylalanine to label the lignin (Crawford and Crawford, 1976). [Lignin-l4C]-lignocelluloses were prepared from the twigs by grinding and extracting the phloem layer (Crawford and Crawford, 1976). Specific activities of the maple and spruce lignocelluloses were 539 and 902 dpm mg-l, respectively. Triplicate culture tubes containing 50 mg of labeled lignocellulose each were autoclaved and 15 ml of a sterile liquid medium [oven-dried Rila Marine Salts (Rila Products, Teaneck, New Jersey) 20 g, yeast

Growth of filamentous marine fungi in a continuous culture system

A continuous culture system has been designed for the cultivation of certain species of marine fungi. Growth in this apparatus was compared with growth in batch culture. Growth of the three marine species tested (Zalerion maritimum, Humicola alopallonella, and Monodictys pelagica) was significantly higher in continuous culture than in batch culture.Growth of two isolates of Z. maritimum was compared on three inorganic nitrogen sources and one organic nitrogen source. Growth of the fungus in the continuous system differed both qualitatively and quantitatively from that in batch culture. Both isolates showed greater growth on the organic nitrogen source in the closed system. In the continuous system, growth was equivalent on all nitrogen sources.

Experimentelle Untersuchungen zur Produktion und Aktivität cellulolytischer Enzyme bei höheren Pilzen aus dem Meer- und Brackwasser

Twenty isolations of marine higher fungi were examined in regard to their cellulolytic capabilities. Application of the viscosimetric method produced detailed information on the cellulolytic activities of marine fungi. However, only the Cx-component of the total cellulase-complex could be estimated by this method. The most active species were Dendryphiella salina, Chaetomium ramipilosum, Asteromyces cruciatus and Humicola alopallonella. Only very slight or no Cx-activity was observed in Cirrenalia macrocephala, Monodictys pelagica and Zalerion maritimum. This finding reveals no correlation between the cellulolytic activity of the fungi in vitro and their frequency on wood-substrates in situ. For example, differences in the intensity of Cx-cellulase production of D. salina are caused by variations in salinity and composition of the nutrient broth, especially by the kind of cellulose added for enzyme induction and by the addition or absence of glucose. Most of the Cx-cellulase produced is present in the cell-free culture-filtrate. Only a small quantity is absorbed by the cellulose particles or the fungal mycelia. Parallel to the mycelial growth, and accompanied by a shift in pH, the Cx-cellulase-activity rises continuously, attaining a maximum after several weeks. During further cultivation, the maximum remains more or less constant for a long period. Tests using different methods, e.g. cellulose-powder-agarplates, proved unsuitable because of spreading hyphal growth, dark pigmentation, heavy sexual or asexual sporulation and relatively low cellulase production during short culture periods.

Marine fungi isolated from a Kraft pulp mill outfall area

Wood- and leaf-inhabiting marine fungi were collected from two depths near the effluent outlets of a Kraft pulp mill in Howe Sound, British Columbia. Other sites which were not directly affected by pulp mill effluents were also sampled. All groups of fungi grew poorly on baits which rested on the bottom at the mill. At a depth of 30 cm, Phycomycetes were isolated as frequently from the mill as from control sites. Of the Fungi Imperfecti, Monodictys pelagica (Johnson) Jones was isolated more frequently from the mill than from control sites; Zalerion maritimum (Linder) Anastasiou was isolated less frequently from the mill than from control sites. Phialophora fastigiata (Lagerb. &amp; Melin) Conant was isolated exclusively from the pulp mill station. Ascomycetes were rarely found on panels submerged at the pulp mill.Hydrographic measurements showed that water temperature at the mill sample site was not affected by the effluent. Salinity and pH were generally lower at the pulp mill than at the control site, and may have been partially responsible for the observed distributional differences.

Lignicolous marine fungi from southern Chile, including a review of distributions in the southern hemisphere

Fifteen species of wood-inhabiting marine fungi recovered from intertidal wood collected in southern Chile (lat. 43°–55° S), eight Ascomycetes and seven Fungi Imperfecti, are new records for the cold temperate zone of the southern hemisphere. Three of the Ascomycete species were previously reported south of the equator from Australia and one of the Fungi Imperfecti is known from southern Brazil. Monodictys pelagica (Johnson) Jones was the most frequently collected species. The species composition of the Chilean collection is strikingly similar to the species composition of the intertidal lignicolous mycoflora of northern cold temperate waters. A distributional bipolarity is suggested for this group of "cold water" species. A review of lignicolous and algicolous marine fungi reported for the southern hemisphere is included.

Lignicolous marine fungi from Nova Scotia

Nineteen species of lignicolous marine fungi, including 13 Ascomycetes and 6 Deuteromycetes, are reported from Nova Scotia. Monodictys pelagica (Johnson) Jones and Zalerion maritimum (Linder) Anastasiou are previously reported. The other 17 species are new records for Nova Scotia.

Intertidal lignicolous fungi from Newfoundland

From a total of 18 species of lignicolous fungi collected, 11 Ascomycetes, 1 Basidiomycete, and 3 Deuteromycetes represent first records from Newfoundland. Digitatispora marina Doguet and Zalerion varium Anastasiou are reported from the western North Atlantic area and the nematode-trapping Hyphomycete Arthrobotrys superba Corda was collected in a marine habitat. The Deuteromycete Monodictys pelagica (Johnson) Jones was the most frequently collected species.