In silico identification and expression analysis of superoxide dismutases in Tenebrio molitor.

BACKGROUND: Insects encounter various environmental stresses, in response to which they generate reactive oxygen species (ROS). Superoxide dismutase (SOD) is an antioxidant metalloenzyme that scavenges superoxide radicals to prevent oxidative damage. OBJECTIVE: To investigate expressions of SODs under oxidative stress in Tenebrio molitor. METHODS: Here, we investigated the transcriptional expression of SODs by pesticide and heavy metals in Tenebrio moltior. First, we searched an RNA-Seq database for T. molitor SOD (TmSOD) genes and identified two SOD isoforms (TmSOD1-iso1 and iso2). We examined their activities under developmental stage, tissue-specific, and various types (pesticide and heavy metal) of oxidative stress by using qPCR. RESULTS: Our results revealed two novel forms of TmSODs. These TmSODs had a copper/zinc superoxide dismutase domain, active site, Cu2+ binding site, Zn2+ binding site, E-class dimer interface, and P-class dimer interface. TmSODs (TmSOD1-iso1 and iso2) were expressed in diverse developmental phases and tissues. Pesticides and heavy metals caused an upregulation of these TmSODs. CONCLUSION: Our findings suggest that the two TmSODs have different functions in T. molitor, providing insights into the detoxification ability of T. molitor.

Marine crime scene investigation using Balanus sp. fouling patterns.

Marine biofouling occurs when microorganisms, plants, algae, or animals gather on any surface of a man-made object or natural structure. Biofouling organisms are important components of marine ecosystems and vary seasonally and regionally, with environmental factors such as temperature, amount of light, and nutrient availability. Since marine organisms have unique growth patterns, they can be used in marine forensic investigations to estimate time and environment. As few such studies have been done, this study analyzed the growth rates of Balanus on 100 × 100 mm panels of PVC, stainless steel, wood, and cloth and compared these with environmental factors such as temperature. Sets of panels were immersed in Sokcho Harbor, South Korea, each month, and observed monthly after immersion using American Society for Testing and Materials methods. The Balanus on the test panels grew to 1-20 mm and showed different growth patterns depending on when the panels were first immersed.

Sea urchin repelling Tannin- FeIII complex coating for ocean macroalgal afforestation.

Intense seaweed grazing by sea urchins has destroyed kelp forests and accelerated the transformation of these forests into barren areas known as urchin barrens. Once the sea urchins occupy the barren ground, it becomes more challenging to restore the kelp forests. Although phlorotannin, a primary herbivore defense chemical secreted by kelp, has been reported to discourage feeding activities of marine herbivores but the direct application of naturally extracted phlorotannin does not effectively repel sea urchins. In this study, we applied a simple and green Tannin-FeIII (TA-FeIII) coating on substrates as a sea urchin repellent using a cheap, ecofriendly tannin (TA) obtained from biomass as an alternative to phlorotannin. In a model aquarium experiment, most of the sea urchins (Anthocidaris crassispina) in the tank evaded the TA-FeIII-coated substrates. In field tests with 300 sea urchins, the majority of sea urchins could not crawl over the TA-FeIII-coated rope for more than 2 h in contrast to the control group. Hence, the safety, cost-effectiveness, and scalability of the TA-FeIII coating make it a practical candidate to protect the kelp ecosystem from sea urchins.

Immobilization of planktonic algal spores by inkjet printing.

The algal cell immobilization is a commonly used technique for treatment of waste water, production of useful metabolites and management of stock culture. However, control over the size of immobilized droplets, the population of microbes, and production rate in current techniques need to be improved. Here, we use drop-on-demand inkjet printing to immobilize spores of the alga Ecklonia cava within alginate microparticles for the first time. Microparticles with immobilized spores were generated by printing alginate-spore suspensions into a calcium chloride solution. We demonstrate that the inkjet technique can control the number of spores in an ejected droplet in the range of 0.23 to 1.87 by varying spore densities in bioink. After the printing-based spore encapsulation, we observe initial sprouting and continuous growth of thallus until 45 days of culture. Our study suggest that inkjet printing has a great potential to immobilize algae, and that the ability to control the number of encapsulated spores and their microenvironments can facilitate research into microscopic interactions of encapsulated spores.

A strategy toward reconstructing the healthcare system of a unified Korea.

This road map aims to establish a stable and integrated healthcare system for the Korean Peninsula by improving health conditions and building a foundation for healthcare in North Korea through a series of effective healthcare programs. With a basic time frame extending from the present in stages towards unification, the roadmap is composed of four successive phases. The first and second phases, each expected to last five years, respectively, focus on disease treatment and nutritional treatment. These phases would thereby safeguard the health of the most vulnerable populations in North Korea, while fulfilling the basic health needs of other groups by modernizing existing medical facilities. Based on the gains of the first two phases, the third phase, for ten years, would prepare for unification of the Koreas by promoting the health of all the North Korean people and improving basic infrastructural elements such as health workforce capacity and medical institutions. The fourth phase, assuming that unification will take place, provides fundamental principles and directions for establishing an integrated healthcare system across the Korean Peninsula. We are hoping to increase the consistency of the program and overcome several existing concerns of the current program with this roadmap.

Single dose toxicity studies of sulfated water soluble beta-D-glucan in Sprague-Dawley rats.

The fungal beta-D-glucan is a biological response modifier (BRM), but a major obstacle to the clinical utilization of these BRMs is their relative insolubility in aqueous media. We made soluble sulfated-beta-glucan (SGL) from insoluble beta-glucan (IGL) by sulfation method. In single dose toxicity study of SGL for 7 days, no negative effects on body weight or food consumption of rats were evident below a dose rate of 2,000 mg kg(-1) SGL. No clinical pathology, functional/behavioral, or gross observations indicating toxicity were detected. In hematology and biochemistry, statistically significant increases of WBC and neutrophils (P < 0.01) in male and increase of MCV (P < 0.05) in females was observed. However, since the changes were not dose-responsive, the effects were considered to be of no toxicological significance. These results suggest that chemically modified sulfated-beta-D-glucan was lesstoxic than the insoluble b-glucan and not considered acutely toxic following peritoneal exposure to 2,000 mg kg(-1) day(-1) in Sprague-Dawley rats.

Ramalin, a novel nontoxic antioxidant compound from the Antarctic lichen Ramalina terebrata.

Ramalin (γ-glutamyl-N'-(2-hydroxyphenyl)hydrazide), a novel compound, was isolated from the methanol-water extract of the Antarctic lichen Ramalina terebrata by several chromatographic methods. The molecular structure of ramalin was determined by spectroscopic analysis. The experimental data showed that ramalin was five times more potent than commercial butylated hydroxyanisole (BHA) in scavenging 1-diphenyl-2-picryl-hydazil (DPPH) free radicals, 27 times more potent in scavenging 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid free radicals (ABTS(+)) than the vitamin E analogue, trolox, and 2.5 times more potent than BHT in reducing Fe(3+) to Fe(2+) ions. Similarly, ramalin was 1.2 times more potent than ascorbic acid in scavenging superoxide radicals and 1.25 times more potent than commercial kojic acid in inhibiting tyrosinase enzyme activity, which ultimately leads to whitening of skin cells. Ramalin showed no or very little cytotoxicity in human keratinocyte and fibroblast cells at its antioxidant concentration. Furthermore, ramalin was assessed to determine its antioxidant activity in vivo. One microgram per milliliter ramalin significantly reduced the released nitric oxide (NO) and 0.125 µg/ml ramalin reduced the produced hydrogen peroxide (H(2)O(2)) in LPS (lipopolysaccharide)-stimulated murine macrophage Raw264.7 cells. Considering all the data together, ramalin can be a strong therapeutic candidate for controlling oxidative stress in cells.

Antibacterial activities of Ramalin, usnic acid and its three derivatives isolated from the Antarctic lichen Ramalina terebrata.

The development of new antibacterial compounds is an urgent issue to meet the evolution of resistivity of pathogenic bacteria against the available drugs. The objective of this study was to investigate the antibacterial compounds from the Antarctic lichen species Ramalina terebrata. A total of five compounds, usnic acid, usimine A, usimine B, usimine C, and ramalin, were isolated by bioactivity guided-fractionation of the methanol extract of R. terebrata after several chromatographic procedures. The qualitative antibacterial activities of the crude extract and isolated compounds were determined by the disk diffusion method while the minimum inhibitory concentration (MIC) determination assay gave the quantitative strength of the test samples. All the test samples showed antibacterial activity against Bacillus subtilis. The crude extract and usnic acid showed antibacterial activity against Staphylococcus aureus. The MIC values of the isolated compounds against B. subtilis were in the range of 1 to 26 microg/mL. These observed experimental data showed the strong antibacterial potential of these compounds against B. subtilis.

Solubilization of water-insoluble beta-glucan isolated from Ganoderma lucidum.

The fungal beta-D-glucan is a biological response modifier (BRM), but a major obstacle to the clinical utilization of beta-glucan BRMs is thei relative lack of solubility in aqueous media. Water insoluble fungal glucans extracted by alkali from the mycelia of Ganoderma lucidum were sulfated to yield their corresponding water-soluble derivatives. Insoluble glucan is dissolved in methyl sulfoxide and urea, and is partially sulfated with sulfuric acid. The sulfated glucan (SGL) yield prepared from insoluble glucan (IGL) was 85%, the sulfation degree of SGL was about 14.9%, and the solubility of SGL was above 95% in water. The monosugar SGL content was 34.9% alpha-glucose and 35.9% beta-glucose. The mean molecular weight (MW) of SGL was shown as a single peak on Sepharose CL-4B column chromatography, and their MW was approximately 9.3 kDa. The 13C NMR spectrum analysis shows that SGL has a high similarity with the beta-(1-->3)-linked triple-helical control.

Antibacterial potential of Antarctic lichens against human pathogenic Gram-positive bacteria.

Extracts from five Antarctic lichens (L3, Stereocaulon alpinum; L5, Ramalina terebrata; L6, Caloplaca sp.; L8, Lecanora sp.; and L17, Caloplaca regalis) were tested for antimicrobial activities against several clinically important microbes by disk diffusion. The minimum inhibitory concentration (MIC) of each extract was determined by a broth dilution method. Extracts from L3, L5, L6 and L8 were active against two Gram(+) strains. B. subtilis was more sensitive to lichen extracts (except L5) than S. aureus. The MIC of lichen extracts against B. subtilis and S. aureus was observed from 36.7 +/- 0.3 to 953.8 +/- 85.8 microg/mL and 68.5 +/- 0.6 to >1000 microg/mL, respectively. Comparisons of MIC values of Antarctic lichen crude extracts to previously published MIC values of some reported lichen metabolites against Gram(+) bacteria indicated that Antarctic lichens might be an enriched source of effective antibacterial agents against clinically relevant Gram(+) species.

Rapid attachment of spores of the fouling alga Ulva fasciata on biofilms.

Attachment of spores of Ulva fasciata to natural biofilms was examined to probe the basis for specificity in settlement. Within 30 min from initial exposure in laboratory assays, spores attached to 1-, 3-, 6- or 9-day biofilms formed on acid-cleaned glass slides. The greatest number of spores attached to biofilms aged for 6-day (573.3 +/- 45 spores mm2, p<0.025). The Morisita Index (MI) was used to investigate relationships between the spatial pattern of spores on natural biofilms, and was found to be random for 1-, 3- and 6-day biofilms (MI = 0.93, 0.98 and 0.95, respectively), but non-random on 9-day biofilms (0.82). In addition to the attachment of spores to natural biofilms, experimentally manipulated biofilms that provided potentially specific receptor sites were studied. Epifluorescence microscopy of 1-day biofilms confirmed that experimental sugar was incorporated into natural biofilms. The Jacalin galactose specific probe showed a homogeneous pattem of galactose incorporation on biofilms, whereas Concanavalin Aprobe (mannose) showed a discrete pattem for this sugar. Similarly, the addition offetuin to a biofilm was detected as a heterogeneous pattern. Rapid spore attachment of U. fasciata found on natural biotilms was induced by fetuin (1-day: 1482 +/- 46.6 spores mm2); specific molecules similar to fetuin may play a role in triggering settlement Specific sugars and their analogs are important surface receptors and play an integral role in attachment of Ulva fasciata spores to aged biofilms. Biofilm age and the role of specific sugars on attachment are discussed.

A review of epiphyte community development: surface interactions and settlement on seagrass.

A focus of community ecology is the spatial distribution of species assemblages and the interactions among species and abiotic features of the environment. While the ubiquity of species associations is apparent, it is less clear if interactions within a community impart an organizational structure to the community. Do settlement processes in early stages of community development contribute to later community structure? What are the interfacial forces that lead to recruitment and colonization of diverse substrata? This review examines seagrasses as living substrates for epiphyte colonization and the surface interactions which may determine settlement success. These epiphytes include primary producers which contribute to biodiversity and are bioindicators of pollution/nutrient enrichment.

Comparison of the effectiveness of four organic chemoattractants towards zoospores of Ulva pertusa and macrofouling.

Algal spores respond to many environmental variables, especially to chemical "cues". This chemotactic response can be utilized to attract spores, thereby colonization of a new substrata is possible to be influenced. In this attempt, four chemoattractant candidates were screened against spores of Ulva pertusa to reveal their efficiencies. Attachment and subsequent germination of Ulva spores were effectively influenced by these chemoattractant candidates. In particular 100 microg cm2 of D-glucose coating was found to enhance spore attachment by > 150%. Furthermore, field investigations carried out with test panels, clearly indicate the chemoattractive properties of test coatings. In recent years, various anthropogenic activities and natural hazards cause detrimental impacts on the benthic algae and other fishery resources. Artificial reefs have been laid on many coastal regions to increase or restore marine resources. Chemoattractant coatings can be applied on artificial surfaces to increase the colonization of benthic forms. It also can be used in the mariculture devices. Influence of chemoattractants on Ulva spores and fouling biomass estimated on test panels are discussed.

Studies on phyto-and-zooplankton composition and its relation to fish productivity in a west coast fish pond ecosystem.

A fish pond ecosystem on the west coast of Korea was studied for biotic and abiotic factors. The occurrence rate of phytoplankton at the embanked fish farm was 84 times higher to that of shore waters. Phytoplankton species which occurred during the study period were categorized into Cyanophyta, Dinophyta and Bacillariophyta with a total of 26 subgeneric taxa (22 species of Dinophyta, 2 species of Bacillariophyta and 2 species of Cyanophyta). The total cell density during the study period ranged from16 x 103 to 13.59 x 10(5) cells l(-1). As for the zooplankton, the monthly density ranged from 26 - 8.684 x 10(3) cells m(-3) with an average of 126.0 x 10(3) cells m(-3) for April. In the case of May, it ranged from 41 - 3.331 x 10(3) cells m(-3) and its average of 50.3 x 10(3) cells m(-3) which was comparatively less. The varying environmental factors in Seosan embankment A, B and Chonsu Bay waters could have affected the fish farm. According to the results, the concentration of inorganic nitrogen was 0.067-0.106 (average: 0.083) mg l(-1) and the concentration of organic nitrogen was 0.008-0.022 (average: 0.014) mgl(-1). Also due to the release of brackish water at Seosan embankment A and B, the inorganic nitrogen showed an increasing trend. The survival rate of Sabastes schlegeli, and Acanthopagrus schlegeli was high in stations 2H and I (20.87%, 33%) and relatively low in stations 2B to 2F.

Evaluation of antifouling activity of eight commercially available organic chemicals against the early foulers marine bacteria and Ulva spores.

Environmental impacts caused by tin and copper based commercial antifouling (AF) paints were proved to be detrimental to aquatic ecosystems. Therefore, a search of environmental friendly AF compounds to be used in marine paint to protect the surface of maritime developmental structures from the unwanted biofouling is a burning issue of the present time. Commercially available eight organic chemicals--allyl isothiocyanate, beta-myrecene, cis-3-hexenyl acetate, citral, ethyl heptanoate, eugenol, methyl caproate, and octyl alcohol were evaluated forAF activities using both laboratory and field assays. The test chemicals were found to repel the target motile marine bacteria--Alteromonas marina, Bacillus atrophaeus, Roseobactergallaeciensis and Shewanella oneidensis and motile spores of the green alga, Ulva pertusa. The bacterial and Ulva spore repulsion activities of the test chemicals were measured by chemotaxis and agar diffusion methods respectively interestingly these test chemicals were less toxic to the test fouling species. The toxicity of the test chemicals was measured by using antibiotic assay disks against the bacteria and motility test against Ulva spores. Moreover, in field assay, all test chemicals showed a perfect performance ofAF activity showing no fouling during the experimental period of one year Such results and commercial as well as technical feasibility of the test chemicals firmly showed the possibility of using as alternatives of the existing toxic AF agents.

Microalgal growth enhancement by levoglucosan isolated from the green seaweed Monostroma nitidum.

Microalgal growth was enhanced by the addition of levoglucosan to the culture medium. The growth-enhancing compound levoglucosan was isolated from the green seaweed Monostroma nitidum using water extraction, molecular fractionation, DEAE-cellulose column chromatography, and high-performance liquid chromatography. Yield of the compound from seaweed powder was 5 x 10(-3)% (w/w). At 10 mM concentration, levoglucosan enhanced cell growth and the specific growth rate of all feed microalgal species tested (Chaetoceros gracilis, Chlorella ellipsoidea, Dunaliella salina, Isochrysis galbana, Nannochloris oculata, Navicula incerta, Pavlova lutheri, Tetraselmis suecica) in most culture media by approximately 150%. Cellular fatty acid profiles and cell size differed marginally between cultures with and without levoglucosan.

Fouling coverage of a green tide alga, Ulva pertusa on some antifouling test surfaces exposed to Ayagin harbor waters, east coast of South Korea.

Toxic antifouling chemicals released into the seawaters leads to marine environmental degradation. In order to identify a nontoxic antifoulant, an assessment of antifouling (AF) efficacy of some AF candidates was made at Ayagin harbor, east coast of South Korea. In this static panel study conducted during October 2000-March 2001, some commercial antifoulants, seaweed and seagrass extracts were screened. On panel surfaces coated with a seaweed extract, Ishige okamurae exhibited effective AF activity. Ulva pertusa was encountered as a 'monospecific' fouler with fairly high fouling coverage on many of the test panel surfaces. In recent years the increased influx of inorganic pollutants in the coastal waters causes exorbitant growth of fouling marine algae found all along the Korean peninsula. Especially, a cosmopolitan ship fouling alga U. pertusa occur with high abundance. It was largely suggested that the proposed international ban on the toxic antifoulant tributyltin (TBT) had significant effect on the 'green tide' phenomenon occurring in different parts of the world. However, it appears that Korean scenario of 'green tide' is a localized. Antifouling efficacy of some AF coatings and fouling coverage of a green tide alga, U. pertusa are discussed.

TBT toxicity on the marine microalga Nannochloropsis oculata.

Commercial antifouling formulations containing TBT are the major source of organotin contamination in coastal waters. In view of the persisting TBT residues (13 ng Sn l(-1)) in the coastal waters of South Korea, an attempt has been made to evaluate the growth response and biochemical composition of laboratory-cultured Nannochloropsis oculata to TBT toxicity. It is evident that the persisting concentration level of TBT is high enough to cause adverse effect on the microalgal species. The EC50 (24 h) was found to be at 0.89 nM level of TBT for this marine eustigmatophyte N. oculata. Photosynthetic pigment content was significantly affected. At elevated TBT concentrations of 1.0 nM, especially pronounced changes in biochemical composition was found. TBT tolerance of N. oculata and its growth as well as biochemical responses are discussed.

Forest fire ash impact on micro- and macroalgae in the receiving waters of the east coast of South Korea.

Mountain forest fire ash flushed into the eastern coastal waters of South Korea is known to contain cadmium as one of its significant constituents. To study its impact, two representatives of the micro- and macroalgal communities, Ulva pertusa and Nannochloropsis oculata, were exposed to the concentration range of Cd indicated from the forest fire localities. At low concentrations of 0.224-0.448 mg L(-1), a 20% reduction in growth rate of N. oculata was observed. Chlorophyll a pigment concentration was proportionate to the growth reduction while at higher concentrations (1.792 mg L(-1)) pigments were completely leached. In the macrophyte U. pertusa, a similar trend of pigment leaching was observed. Bioaccumulation factors obtained for these rapidly growing algal species revealed excessive bioconcentration of Cd. Variations in the concentration of Cd among the samples collected along the Korean coast clearly indicated the additional source of metal influx from the forest fires.