Identification and characterisation of a novel heptapeptide mackerel by-product hydrolysate, and its potential as a functional fertiliser component.

Functional fertilisers for hydroponics are in great demand. Herein, we isolated peptides from mackerel by-products, a valuable source of bioactive peptides. The pellet-phase fraction obtained after cold-acetone extraction exhibited plant growth-promoting activity in wheat hydroponics, and the presumed peptides were determined to be ≤ 1 kDa based on molecular weight cut-off and tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Recovery of antioxidant and antimicrobial peptides through the reutilization of Nile perch wastewater by biodegradation using two Bacillus species.

Nile perch wastewater was biodegraded using two Bacillus species to recover bioactive substances to enhance its reutilization value. The two Bacillus species successfully produced low-molecular-weight substances with a 47.8% degree of hydrolysis.

Biodegraded mackerel wastewater selectively inhibits harmful algal blooms.

Functional substances from mackerel wastewater were biodegraded and tested for inhibitory activity against harmful algal blooms (HABs) that are detrimental to aquaculture. The supernatant from a 48 h culture of mackerel wastewater had a half-maximal inhibitory concentration of 0.54-0.

Isolation and identification of a novel algicidal peptide from mackerel muscle hydrolysate.

To help remedy damage from harmful algal blooms, an attempt was made to isolate an algicidal substance previously observed to be present in mackerel muscle hydrolysate. Crude extract was obtained by cold acetone precipitation, and it dissolved best in water. Through molecular weight cut-off determination and tricine-SDS PAGE, the algicidal substance was determined to be a peptide of <1 kDa.

Analysis of proinflammatory gene expression by RBIV infection in rock bream, Oplegnathus faciatus.

Early induction of proinflammatory cytokines is known to regulate the later immune responses to inhibit the progress of infectious diseases. In this study, proinflammatory cytokine gene expression has been studied in immune tissues to understand the early immune response induced by megalocytivirus in rock bream (Oplegnathus faciatus). For this, we have cloned interleukin (IL)-1β and IL-8 gene and performed the phylogenetic and structural analysis.

The high reutilization value potential of high-salinity anchovy fishmeal wastewater through microbial degradation.

To provide an option for the reutilization of high-salinity anchovy fishmeal wastewater (FMW), generated during the anchovy fishmeal manufacturing processes, its potential for biodegradation was assessed in 1-l five-neck flasks using a halotolerant and proteolytic microbial consortium. During the first 41 h of biodegradation, the pH, DO, ORP, and dry-sludge weight decreased as the total cell number of the microbial consortium increased steadily; the COD(Cr)/TN ratios remained between 4.0 and 5.

Characterization of salt-tolerant β-glucosidase with increased thermostability under high salinity conditions from Bacillus sp. SJ-10 isolated from jeotgal, a traditional Korean fermented seafood.

The β-glucosidase gene, bglC, was cloned from Bacillus sp. SJ-10 isolated from the squid jeotgal. Recombinant BglC protein overexpression was induced in Escherichia coli.

Reuse of red seaweed waste by a novel bacterium, Bacillus sp. SYR4 isolated from a sandbar.

A potent bacterial strain was isolated from a sandbar and identified as Bacillus sp. SYR4 for the reuse of red seaweed waste. The isolate possessed both agarase and carrageenase activities.

High antioxidant and DNA protection activities of N-acetylglucosamine (GlcNAc) and chitobiose produced by exolytic chitinase from Bacillus cereus EW5.

Chitin-degrading bacterial strains were screened and tested for their ability to degrade shrimp-shell waste (SSW). Among the potential strains, B. cereus EW5 exhibited the highest chitin-degrading ability compared with other strains and produced 24 mg of reducing sugar per gram of dry SSW after 4 days of incubation.

Recovery of algal oil from marine green macro-algae Enteromorpha intestinalis by acidic-hydrothermal process.

In this study, the recovery of algal oil from Enteromorpha intestinalis based on an acidic-hydrothermal reaction was investigated. Overall, the algal oil yield after the acidic-hydrothermal reaction was increased under the conditions of high reaction temperature, high catalyst concentration, and long reaction time within the tested ranges. Significantly, catalyst concentration, compared with reaction temperature and time, less affected algal oil recovery.

Conversion of red-algae Gracilaria verrucosa to sugars, levulinic acid and 5-hydroxymethylfurfural.

This study employed a statistical methodology to investigate the optimization of conversion conditions and evaluate the reciprocal interaction of reaction factors related to the process of red-algae Gracilaria verrucosa conversion to sugars (glucose, galactose), levulinic acid and 5-hydroxymethylfurfural (5-HMF) by acidic hydrolysis. Overall, the conditions optimized for glucose formation included a higher catalyst concentration than did those for galactose, and these conditions for galactose were similar to those for 5-HMF. Levulinic acid production, meanwhile, was optimized at a higher reaction temperature, a higher catalyst concentration, and a longer reaction time than was glucose, galactose or 5-HMF production.

Microbacterium oxydans, a novel alginate- and laminarin-degrading bacterium for the reutilization of brown-seaweed waste.

There is a growing demand for the efficient treatment of seaweed waste. We identified six bacterial strains from the marine environment for the reutilization of brown-seaweed waste, and the most potentially useful strain, Microbacterium oxydans, was chosen and further investigated. Plate assays indicated that this bacterial isolate possessed both alginate lyase and laminarinase activities.

Characterisation of a novel Bacillus sp. SJ-10 β-1,3-1,4-glucanase isolated from jeotgal, a traditional Korean fermented fish.

A novel β-1,3-1,4-glucanase gene was identified in Bacillus sp. SJ-10 (KCCM 90078) isolated from jeotgal, a traditional Korean fermented fish. We analysed the β-1,3-1,4-glucanase gene sequence and examined the recombinant enzyme.

Scaled-up bioconversion of fish waste to liquid fertilizer using a 5 L ribbon-type reactor.

A scaled-up conversion process of fish waste to liquid fertilizer was performed in a 5 L ribbon-type reactor. Biodegradation was performed by inoculation of autoclaved fish waste with 5.84 × 10(5) CFU mL(-1) of mixed microorganisms for 96 h.

Cloning, expression analysis and enzymatic characterization of cathepsin S from olive flounder (Paralichthys olivaceus).

Cathepsin S is a critical protease for the regulation of MHC class II immune responses, and thus is a potential target for developing immunosuppressive drugs in the pathogenesis of degenerative and autoimmune diseases. In this study, we cloned a cDNA encoding for cathepsin S (PoCtS) from the olive flounder, Paralichthys olivaceus. The 1170 bp PoCtS cDNA contained an open reading frame of 1014 bp, which consisted of a 25-residue putative signal peptide, a 96-residue propeptide and the 216-residue mature enzyme.

Molecular cloning, expression, and characterization of cathepsin L from mud loach (Misgurnus mizolepis).

Cathepsin L is an important protease in the initiation of protein degradation and one of the most powerful endopeptidases. In this study, we cloned mud loach (Misgurnus mizolepis) cathepsin L (MlCtL) cDNA, and the pro-mature enzyme of MlCtL (proMlCtL) was expressed in Escherichia coli as a fusion protein with glutathione S-transferase in a pGEX-4 T-1 vector. The recombinant proMlCtL was overexpressed in E.

Coenzyme Q10 production in a 150-l reactor by a mutant strain of Rhodobacter sphaeroides.

For the commercial production of CoQ(10), batch-type fermentations were attempted in a 150-l fermenter using a mutant strain of R. sphaeroides. Optimum temperature and initial aeration rate were found to be 30 degrees C and 2 vvm, respectively.

Identification and characterization of microorganisms from earthworm viscera for the conversion of fish wastes into liquid fertilizer.

Five bacteria isolated from earthworm viscera and identified as Brevibacillus agri, Bacillus cereus, Bacillus licheniformis, and Brevibacillus parabrevis by 16S rRNA sequencing were employed in the conversion of fish wastes generated from a restaurant specializing in sliced raw fish into fertilizer. Within 120h after inoculation of autoclaved fish waste with 5.15 x 10(5) CFU ml(-1) mixed isolates, the amount of dry sludge decreased from 29.

Purification, molecular cloning, and biochemical characterization of subtilisin JB1 from a newly isolated Bacillus subtilis JB1.

An extracellular gelatinolytic enzyme obtained from the newly isolated Bacillus subtilis JB1, a thermophilic microorganism relevant to the aerobic biodegradation process of fish-meal production, was purified via ammonium sulfate precipitation, Sephadex G-200 Gel filtration chromatography, and one-dimensional gel electrophoresis separation and subsequently identified via peptide mass fingerprinting and chemically assisted fragmentation matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The subtilisin JB1 gene was sequenced and its recombinant protein prosubtilisin JB1 was expressed in Escherichia coli, and the purified prosubtilisin JB1 (62 kDa) protein was digested with gelatin, bovine serum albumin, azocasein, fibrinogen, and the fluorogenic peptide substrate Ala-Ala-Phe-7-amido-4-methylcoumarin hydrochloride, whereas the serine protease inhibitors phenylmethylsulfonyl fluoride and chymostatin completely inhibited its enzyme activity at an optimal pH of 7.5.

Molecular cloning, expression analysis and enzymatic characterization of cathepsin K from olive flounder (Paralichthys olivaceus).

We assessed the putative physiological roles of cathepsin K from a flatfish, olive flounder. We cloned a cDNA encoding for cathepsin K (PoCtK), a cysteine protease of the papain family from olive flounder, Paralichthys olivaceus. The tissue-specific expression pattern of PoCtK, determined via real-time PCR analysis, revealed ubiquitous expression in normal tissues with high levels of expression in the spleen and bone marrow.

Influence of temperature shifts on the onset and development of red sea bream iridoviral disease in rock bream Oplegnathus fasciatus.

The effects of various water temperature treatments on the development of red sea bream iridovirus disease (RSIVD) in rock bream Oplegnathus fasciatus challenged with iridovirus Sachun (IVS-1) were determined by measuring the mortality and the viral concentration in the spleen of infected fish. Experimental infections of rock bream with IVS-1 at water temperatures of 18, 21, and 25 degrees C resulted in a cumulative mortality of 100%, but infections at 13 degrees C resulted in 0% mortality, even after 45 d. The disease progressed more rapidly at higher water temperatures; at 25, 21, and 18 degrees C, the mean numbers of days until death were 17, 20, and 30 d, respectively.

Molecular cloning, mRNA expression and enzymatic characterization of cathepsin F from olive flounder (Paralichthys olivaceus).

Cathepsin F is a recently described papain-like cysteine protease of unknown function, and unique among cathepsins due to an elongated N-terminal pro-region, which contains a cystatin domain. In the present study, the cDNA of olive flounder (Paralichthys olivaceus) cathepsin F (PoCtF) was cloned by the combination of homology molecular cloning and rapid amplification of cDNA ends (RACE) approaches. The PoCtF gene was determined to consist of the 1844 bp nucleotide sequence which encodes for a 475-amino acid polypeptide.

Expression of a fusion protein containing human epidermal growth factor and the collagen-binding domain of Vibrio mimicus metalloprotease.

Human epidermal growth factor (hEGF) is a polypeptide of 53 amino acids, is an important autocrine/paracrine factor in the human body, and is used in the pharmaceutical and cosmetics industries. We constructed a fusion hEGF protein with a collagen-binding domain (CBD) composed of 33 amino acids from Vibrio mimicus metalloprotease (VMCBD). The CBD segment of the metalloprotease was fused at the C terminus of the hEGF protein.

Molecular cloning, tissue distribution and enzymatic characterization of cathepsin X from olive flounder (Paralichthys olivaceus).

In this study, we have cloned a cDNA encoding for cathepsin X (PoCtX) from the olive flounder, Paralichthys olivaceus. The presence of an HIP motif, which is conserved in the unique cathepsin X family, PoCtX, clearly shows its relation to the cathepsin X group, apart from the cathepsin L or B subfamily. The results of RT-PCR and real-time PCR analyses revealed ubiquitous PoCtX expression in normal and LPS-stimulated tissues.

Outbreaks and risks of infectious spleen and kidney necrosis virus disease in freshwater ornamental fishes.

We examined the distribution of iridoviruses in 10 freshwater ornamental fish species hatched in Korea and imported from other Asian countries using both 1-step and 2-step polymerase chain reation (PCR). None of the 10 fish species analyzed were free of iridovirus as shown by 2-step PCR positive results, and 3 species yielded 1-step PCR positive results with associated mortality. Cloned PCR amplicons of the adenosine triphosphatase (ATPase) and major capsid protein (MCP) genes in genomic DNA of iridovirus showed the same nucleotide sequences as that of infectious spleen and kidney necrosis virus (ISKNV) isolated from the mandarinfish Siniperca chuatsi.