Aims: Marine bacteria have been reported to produce potential natural pigment with pharmaceutical properties and their growth can be manipulated in the laboratory to increase pigment production and their antimicrobial activity. Hence, this study aimed to enhance the prodigiosin production in Serratia marcescens IBRL USM84 by improving physical conditions. Methodology and results: The quantification of the pigment produced by S. marcescens IBRL USM84, bacterial cell growth, and its antibacterial activity in the broth medium were determined using a spectrophotometry method. Meanwhile, the antibacterial effect of red pigment on MRSA cells was observed under a scanning electron microscope (SEM). This marine isolate produced the highest yield of prodigiosin (6.95 μg/mL) when cultivated in marine broth with the addition of 0.2% of agar, 25 °C incubation temperature, initial medium pH of 7, 150 rpm of agitation speed for 48 h of cultivation time under light illumination. There was an increment of 151.81% in prodigiosin production after enhancement compared to before the enhancement of cultural conditions. SEM observations revealed that severe damage to the cell’s morphologies was exposed to red pigment as indicated by the formation of small dents, which led to completely collapse and eventually, cell death. Conclusion, significance and impact of study A positive correlation between pigment production and antibacterial activity was observed in the present study. The results supported the fact that marine bacteria are a reservoir of various pigments with antimicrobial properties. Also, the pigment production by S. marcescens and its antibacterial activity were significantly influenced by physical parameters.
Prodigiosin ; Serratia marcescens ; Marine Biology

Aims: To investigate early marine biofilm-forming bacterial diversity on immersed antimicrobial-free commercial paint substratum in seawater. Methodology and results: Total ten bacterial strains were successfully isolated and identified by complete 16S rRNA sequencing. The isolates morphological, biochemical properties, biofilm-forming ability, extracellular polymeric substance (EPS) productivity and components were characterised. The morphological and biochemical characterization of the strains showed strains-specific variation. All isolates were strong biofilm producers with four motile strains being both flat-bottom and air-liquid-interface biofilm producers, while other strains were only air-liquid interface biofilm producer. Based on 16S rRNA, three strains were identified as Marinomonas communis, two were Marinomonas sp., while the rest were Alteromonas litorea, Alteromonas sp., Salinimonas lutimaris, Idiomarine baltica and Bacillus niabensis. The amount of EPS that the isolates produced ranged from 1.95 to 2.89 g/L and productivity of EPS was inversely correlated with the cell biomass. Analysis of the extracted EPS using attenuated total reflectance-fourier transform infrared (ATR-FTiR) showed that all isolates EPS contained carbohydrates, nucleic acid, protein, DNA/RNA and lipid. Conclusion, significance and impact of study Bacterial diversity in early stages of biofilm on the commercial paint surface was dominated by Gram-negative bacteria from Gammaproteobacteria class. Isolates with superior cell growth showed lowest EPS production. This finding was expected to provide knowledge on distribution of different marine bacterial species in the biofilm on paint coated surfaces which may beneficial to formularize a new antibiofilm paint additive.
Biofilms ; Marine Biology

The crude extracts of the fermentation broth from a marine sediment-derived actinomycete strain, Saccharothrix sp. 10-10, showed significant antibacterial activities against drug-resistant pathogens. A genome-mining PCR-based experiment targeting the genes encoding key enzymes involved in the biosynthesis of secondary metabolites indicated that the strain 10-10 showed the potential to produce tetracenomycin-like compounds. Further chemical investigation of the cultures of this strain led to the identification of two antibiotics, including a tetracenomycin (Tcm) analogs, Tcm X (1), and a tomaymycin derivative, oxotomaymycin (2). Their structures were identified by spectroscopic data analysis, including UV, 1D-NMR, 2D-NMR and MS spectra. Tcm X (1) showed moderate antibacterial activities against a number of drug-resistant pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) pathogens, with the MIC values in the range of 32-64 microg x mL(-1). In addition, 1 also displayed significant cytotoxic activities against human cancer cell lines, including HL60 (leukemia), HepG2 (liver), and MCF-7 (breast) with the IC 50 values of 5.1, 9.7 and 18.0 micromol x L(-1), respectively. Guided by the PCR-based gene sequence analysis, Tcm X (1) and oxotomaymycin (2) were identified from the genus of Saccharothrix and their 13C NMR data were correctly assigned on the basis of 2D NMR spectroscopic data analysis for the first time.
Actinomycetales ; chemistry ; genetics ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Benzodiazepinones ; chemistry ; isolation & purification ; pharmacology ; Cell Line, Tumor ; Data Mining ; methods ; Drug Resistance, Bacterial ; Enterococcus faecalis ; drug effects ; Fermentation ; Genomics ; Humans ; Inhibitory Concentration 50 ; Marine Biology ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Microbial Sensitivity Tests ; Molecular Structure ; Naphthacenes ; chemistry ; isolation & purification ; pharmacology ; Phylogeny ; Staphylococcus epidermidis ; drug effects

In the last decade, along with the development of taxonomy research in marine-derived actinobacteria, more and more halogenated natural products were discovered from marine actinobacteria. Most of them showed good biological activity and unique structure compared to those from land. The special halogenation mechanism in some compounds' biosynthesis has drawn great attention. So in this review, we focus on the halogenated natural products from marine actinobacteria and their halogenation mechanisms.
Actinobacteria ; chemistry ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Biological Products ; chemistry ; isolation & purification ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Halogenation ; Humans ; Marine Biology ; Molecular Structure

Marine can be considered as a rather unexplored source of biological material. Production of algal oligosaccharides by using valuable enzymes from marine origin has become an important way to utilize marine resources. As one of algal tool enzymes, the use of alginate lyases has been focused mainly on development and application of alginate oligosaccharides with bioactive function in recent years. In this paper, we reviewed the research of alginate lyases over the past decade in several aspects, including their origin, diversity, substrate specification, mode of action, structure and catalysis mechanism, assay of enzyme activity, enzyme characterization, as well as our own experience on this subject. At the end of the review, the application prospects of alginate lyases are presented.
Alginates ; metabolism ; Glucuronic Acid ; metabolism ; Hexuronic Acids ; metabolism ; Marine Biology ; methods ; Oligosaccharides ; metabolism ; Phaeophyta ; enzymology ; Polysaccharide-Lyases ; classification ; isolation & purification ; metabolism ; Substrate Specificity

The discovery of quorum sensing (QS) system and its critical role in bacterial virulence have revealed a new way to attack pathogenic bacterium. The pathogenecity of QS deletion mutants decreases significantly. Targeting bacterial QS system is a promising therapeutic approach to control infections and anti-microbial resistance. To obtain natural QS inhibitors from marine organisms, marine fungi (69 strains) were isolated from marine mollusca, and their extracts were screened using improved QSIS2 (Quorum Sensing Inhibitor Selector 2) assay and Chromobacterium violaceum CV026. To improve the efficiency of QSIS2 screening, 2,3,5-triphenyltetrazolium chloride (TTC) staining method was used. Extract from strain QY013 was found to have QS inhibitory activity. Further experiment indicated that pyocyanin in Pseudomonas aeruginosa PAOI and violacein in C. violaceum CV026 were reduced by QY013 extract, without affecting bacterial growth. Morphological and 18S rDNA sequence analysis revealed that strain QY013 was most closely related to Penicillium species. The above results suggest that active constituents from QY013 may be used as novel antimicrobial agents against bacterial infection.
Animals ; Anti-Infective Agents ; isolation & purification ; metabolism ; pharmacology ; Bacterial Physiological Phenomena ; Fungi ; isolation & purification ; physiology ; Marine Biology ; Mollusca ; microbiology ; Penicillium ; isolation & purification ; metabolism ; Pseudomonas aeruginosa ; drug effects ; metabolism ; pathogenicity ; Quorum Sensing ; drug effects ; Virulence ; drug effects

Ocean is a unique and excellent resource that provides a diverse array of intriguing natural products. Marine natural products have demonstrated significant and extremely potent biological activities and have captured the attention of natural products chemists in the past few decades. It is increasingly recognized that a wealth of fascinating natural products and novel chemical entities will play a dominant role in the discovery of useful leads for the development of pharmaceutical agents and provide useful probes to lead to breakthroughs in a variety of life-science fields. This article focused on the research progress of chemistry of marine natural products in recent five years.
Alkaloids ; chemistry ; isolation & purification ; pharmacology ; Animals ; Anti-Infective Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Aquatic Organisms ; chemistry ; Biological Products ; chemistry ; isolation & purification ; pharmacology ; Humans ; Macrolides ; chemistry ; isolation & purification ; pharmacology ; Marine Biology ; Marine Toxins ; chemistry ; isolation & purification ; pharmacology ; Molecular Structure ; Peptides ; chemistry ; isolation & purification ; pharmacology ; Steroids ; chemistry ; isolation & purification ; pharmacology ; Terpenes ; chemistry ; isolation & purification ; pharmacology

OBJECTIVETo explore Effects of marine collagen peptides (MCPs) on markers of metablic nuclear receptors, i.e peroxisome proliferator-activated receptor (PPARs), liver X receptor (LXRs) and farnesoid X receptor (FXRs) in type 2 diabetic patients with/without hypertension. METHOD Study population consisted of 200 type 2 diabetic patients with/without hypertension and 50 healthy subjects, all of whom were randomly assigned to MCPs-treated diabetics (n = 50), placebo-treated diabetics (n = 50), MCPs-treated diabetics with hypertension (n=50), placebo-treated diabetics with hypertension (n = 50), and healthy controls (n = 50). MCPs or placebo (water-soluble starch) were given daily before breakfast and bedtime over three months. Levels of free fatty acid, cytochrome P450, leptin, resistin, adiponectin, bradykinin, NO, and Prostacyclin were determined before intervention, and 1.5 months, and 3 months after intervention. Hypoglycemia and the endpoint events during the study were recorded and compared among the study groups.

RESULTAt the end of the study period, MCPs-treated patients showed marked improvement compared with patients receiving placebo. The protection exerted by MCPs seemed more profound in diabetics than in diabetics with hypertension. In particular, after MCPs intervention, levels of free fatty acid, hs-CRP, resistin, Prostacyclin decreased significantly in diabetics and tended to decrease in diabetic and hypertensive patients whereas levels of cytochrome P450, leptin, NO tended to decrease in diabetics with/without hypertension. Meanwhile, levels of adiponectin and bradykinin rose markedly in diabetics following MCPs administration.

CONCLUSIONMCPs could offer protection against diabetes and hypertension by affecting levels of molecules involved in diabetic and hypertensive pathogenesis. Regulation on metabolic nuclear receptors by MCPs may be the possible underlying mechanism for its observed effects in the study. Further study into its action may shed light on development of new drugs based on bioactive peptides from marine sources.

Adipokines ; blood ; Aged ; Biomarkers ; blood ; Bradykinin ; blood ; C-Reactive Protein ; metabolism ; Collagen ; therapeutic use ; Cytochrome P-450 Enzyme System ; blood ; Diabetes Mellitus, Type 2 ; blood ; complications ; drug therapy ; Epoprostenol ; blood ; Fatty Acids, Nonesterified ; blood ; Female ; Humans ; Hypertension ; blood ; complications ; drug therapy ; Male ; Marine Biology ; Middle Aged ; Nitric Oxide ; blood ; Peptides ; therapeutic use ; Prospective Studies ; Receptors, Cytoplasmic and Nuclear ; metabolism

OBJECTIVETo investigate the protective effect of marine collagen peptides (MCPs) on the skin of aged mice induced by D-galactose.

METHODSSubchronic toxicity study was conducted while D-galactose induced subacute aging model was established. D-galactose dose of 0.125 g/kg body weight was intraperitoneally injected daily for 90 days. Marine collagen peptide 0.225, 0.450, 1.350 g/kg body weight were administered by oral gavage. Superoxide dismutase (SOD), catalase (CAT) activity and malondialdehyde (MDA) content in blood serum were measured, along with cutaneous histopathology examination.

RESULTSEpidermal thickness was significantly higher in MCPs treated group. Number and activity of fibroblast in MCPs treated dermis was increased prominently. The activity of SOD in 0.225, 0.450, 1.350 g/kgbw MCPs treated groups were 455.52 +/- 11.39, 460.15 +/- 18.09, 468.59 +/- 27.25 U/ml respectively, each of which was significantly higher than that in model control group; the activity of serum CAT in 0.225, 1.350 g/kgbw MCPs treated groups (21.33 +/- 4.82, 21.69 +/- 1.68 U/ml) were obviously increased compared with that in model control group (17.14 +/- 2.81 U/ml); MDA level in 0.450, 1.350 g/kgbw MCPs treated groups were 5.67 +/- 0.93, 5.76 +/- 1.02 nmol/ml respectively, each of which was significantly lower than that in model control group (7.63 +/- 1.37 nmol/ml).

CONCLUSIONSThe results showed that MCPs might play a protective role on skin aging by improving the activity of antioxidant.

Animals ; Antioxidants ; pharmacology ; Collagen ; pharmacology ; Male ; Malondialdehyde ; blood ; Marine Biology ; Mice ; Peptides ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Skin Aging ; drug effects ; Superoxide Dismutase ; blood

OBJECTIVETo investigate the effects of marine collagen peptide on adenine-induced chronic renal function impairment in rats.

METHODSAdenine suspension (100 mg/kg ) was given to Sprague-Dawley rats to made the model of renal function impairment. Marine collagen peptide 1.125 g x kg(-1) x d(-1) and 2.25 g x kg(-1) x d(-1) were administered intragastricly in two intervention groups. In addition, adenine suspension (100 mg/kg ) was given. Experiment was kept 12 weeks. Time-dependent levels of serum creatinine (Cr), urea nitrogen (BUN) and creatinine clearance rate were monitored. Kidney ultramicrostructure was checked through transmission electron microscope.

RESULTSIn model group, level of serum Cr, BUN and Ccr of 5, 8, 12th week respectively were: (182.2 +/- 119.52, 308.17 +/- 88.37, 347.57 +/- 68.24; 29.20 +/- 16.48, 63.03 +/- 18.68, 95.53 +/- 24.88; 0.53 +/- 0.23, 0.17 +/- 0.13, 0.14 +/- 0.08). Serum Cr, BUN levels in marine collagen peptide 2.25 g x kg(-1) x d(-1) treated rats were lower and Ccr was higher significantly than that of model group. Level of serum Cr, BUN and Ccr of 5, 8, 12th week in marine collagen peptide treatment group respectively were: (105.60 +/- 11.84, 175.40 +/- 73.93, 240.14 +/- 71.53; 23.62 +/- 3.89, 41.90 +/- 23.78, 72.93 +/- 26.12; 0.99 +/- 0.35, 0.45 +/- 0.28, 0.26 +/- 0.06). Besides, kidney ultramicrostructure damage was ameliorated. Favorable effect of marine collagen peptide 1.125 g x kg(-1) x d(-1) was also observed on renal function impairment, but the difference compared to model group was not significant.

CONCLUSIONMarine collagen peptide at a dose of 2.25 g x kg(-1) x d(-1) might slow down the progression of chronic renal function impairment induced by adenine in rats.

Adenine ; adverse effects ; Animals ; Collagen ; administration & dosage ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Male ; Marine Biology ; Peptides ; administration & dosage ; Rats ; Rats, Sprague-Dawley ; Renal Insufficiency, Chronic ; chemically induced ; prevention & control