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The development of chitinase tailored for the bioconversion of chitin to chitin oligosaccharides has attracted significant attention due to its potential to alleviate environmental pollution associated with chemical conversion processes. In this present investigation, we purified extracellular chitinase derived from marine Bacillus haynesii to homogeneity and subsequently characterized it. The molecular weight of Bh Chi was approximately 35 kDa. Bh Chi displayed its peak catalytic activity at pH 6.0, with an optimal temperature of 37 °C. It exhibited stability across a pH range of 6.0–9.0. In addition, Bh Chi showed activation in the presence of Mn2+ with the improved activity of 105 U mL−1. Ca2+ and Fe2+ metal ions did not have any significant impact on enzyme activity. Under the optimized enzymatic conditions, there was a notable enhancement in catalytic activity on colloidal chitin with K m of 0.01 mg mL−1 and V max of 5.75 mmol min−1. K cat and catalytic efficiency were measured at 1.91 s−1 and 191 mL mg−1 s−1, respectively. The product profiling of Bh Chi using thin layer chromatography and Mass spectrometric techniques hinted an exochitinase mode of action with chitobiose and N-Acetyl glucosamine as the products. This study represents the first report on an exochitinase from Bacillus haynesii. Furthermore, the chitinase showcased promising antifungal properties against key pathogens, Fusarium oxysporum and Penicillium chrysogenum , reinforcing its potential as a potent biocontrol agent. [Display omitted] [ABSTRACT FROM AUTHOR]

Demethoxyfumitremorgin C, a secondary metabolite of the marine fungus, Aspergillus fumigatus , had been reported to demonstrate cytotoxic effect on mouse tsFT210 cells. However, no information is available regarding its functional mechanism and the chemo-sensitization effects on different kinds of human cancer cells. We found that treatment of demethoxyfumitremorgin C inhibited the cell viability of PC3 human advanced prostate cancer cells, induced apoptosis as determined by Annexin V/propidium iodide double staining, and decreased mitochondrial membrane potential. Demethoxyfumitremorgin C induced apoptosis was associated with downregulation of anti-apoptotic proteins: Ras, PI3K, Akt, Bcl-xL, and Bcl-2, and upregulation of pro-apoptotic Bax. Demethoxyfumitremorgin C activated caspase-3, -8, and -9, leading to PARP cleavage. Additionally, caspase inhibitors blocked demethoxyfumitremorgin C-induced apoptosis of PC3 cells. These results suggest that demethoxyfumitremorgin C from Aspergillus fumigatus inhibits the proliferation of PC3 human prostate cancer cells via the intrinsic (mitochondrial) and extrinsic pathway, followed by downstream events leading to apoptotic cell death. Demethoxyfumitremorgin C could therefore, serve as a useful agent to treat human advanced prostate cancer. [ABSTRACT FROM AUTHOR]

Floridoside [α-D-galactopyranosyl-(1-2)-L-glycerol] from marine red algae Laurencia undulata ( L. undulata ) has received considerable attention as a bioactive compound especially for its beneficial effects on human health. This study aimed to evaluate the effect of floridoside in the process of osteogenic differentiation in murine bone marrow mesenchymal (D1) cells and elucidate the mechanism underlying the effect. Under the osteogenic differentiation condition in D1 cells, floridoside showed up-regulation of the sequential markers such as alkaline phosphate (ALP), type I collagen, osteocalcin/osteopontin and mineralisation in the progression. In addition, mRNA levels of Runx-2 and Osterix with floridoside showed remarkable increase at days 14 and 21 compared to the control cells with only ODM media. Thus, our results suggest that floridoside can promote osteogenic differentiation via controlling the sequential markers at the early and late stages of osteogenic differentiation in D1 cells, and it may be a potential therapeutic agent for bone formation. [ABSTRACT FROM AUTHOR]

Fibrosis is generally characterized by an excessive accumulation and deposition of extracellular matrix (ECM) that progressively leads to the destruction of functional nephrons of the kidney. Current study is aimed to propose a probable antifibrotic mechanism of gliotoxin, isolated from marine Aspergillus fumigatus strain, in proximal tubule renal epithelial cells by inhibiting HIF-1α, Ang-II and NF-κB in a dose dependent manner. GTX at a concentration of 1.6 ng/ml also showed more than 80% cell viability. Scanning Electron Microscopy, fluorescence microscopy, FACS, mRNA and protein profiles further confirmed that gliotoxin reverses the epithelial to mesenchymal transition in HK-2 cells by scavenging the production of reactive oxygen species ( g = 69.7) when compared to negative control ( g = 467.74). Under the light of obtained results, the present study holds immense promise for the biomedical implication of the fungal metabolite, Gliotoxin in medicine for treating various clinical cases of renal fibrosis. [ABSTRACT FROM AUTHOR]

Seafood processing by-product, skate ( Okamejei kenojei ) skin, was utilized to isolate active peptides with antihypertensive effect. Two peptides (MVGSAPGVL, 829 Da and LGPLGHQ, 720 Da) were purified from skate skin gelatin. In human endothelial cells, nitric oxide (NO) synthesis was found to be increased and eNOS phosphorylation was upregulated by the peptides. The peptides exhibited inhibitory activities on the production and expression of IL-6. Furthermore, the peptides down-regulated the expression levels of endothelin-1. The peptides inhibited the NF-κB and the phosphorylation of MAPK pathways. In addition, the activation of the PI3K/Akt pathway by the peptides was confirmed. The present study demonstrated that the purified peptides had vasorelaxant effects via endothelium-dependent NO signaling through activation of the PI3K/Akt-eNOS pathway and inhibition of the NF-κB and MAPK pathways. The purified peptides could be used in the food industry as functional ingredients with potent benefits in reducing the risk of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Abstract: Marine microorganisms have received mounting attention in biodiscoveries due to their exclusive physicochemical characteristics which have been acquired as an adaptation to prevailing extreme conditions in the marine environment. It has been noticed that those unique marine microbes and their biologically active metabolites are potential sources to be used as sustainable food and pharmaceutical ingredients. Even though dozens of research articles demonstrate the immense potentials of marine microbial metabolites as lead compounds in drugs and pharmaceutical developments, their role as food ingredients is poorly addressed. However, recent advances in food technology have opened up a number of novel avenues to develop natural substances as food or food ingredients. In this context, this review aims at revealing and discussing prospective applications of marine microorganisms and their metabolites in modern nutraceuticals and functional foods. [Copyright &y& Elsevier]

Abstract: Bone homeostasis is maintained through a balance between osteoblastic bone formation and osteoclastic bone resorption. Aging induces bone loss due to decreased osteoblastic bone formation and increased osteoclastic bone resorption. Osteoporosis with its accompanying decrease in bone mass is widely recognized as a major public health problem. It is undoubted that pharmacological and nutritional factors are involved in the prevention of age-related bone loss. In the search for the appropriate treatment of osteoporosis, there is an interesting area of marine organisms and phytopharmacology. Extracts of marine algae and other marine derived compounds have a favorable effect on bone metabolism. This review discusses the current pharmacological therapies for osteoporosis and bioactive natural products from marine for the anti-osteoporotic research. [Copyright &y& Elsevier]

Abstract: Recently, much attention has been paid by consumers toward natural bioactive compounds as functional ingredients in nutraceuticals. Marine algae are considered as valuable sources of structurally diverse bioactive compounds. Marine algae are rich in sulfated polysaccharides (SPs) such as carrageenans in red algae, fucoidans in brown algae and ulvans in green algae. These SPs exhibit many health beneficial nutraceutical effects such as antioxidant, anti-allergic, anti-human immunodeficiency virus, anticancer and anticoagulant activities. Therefore, marine algae derived SPs have great potential to be further developed as medicinal food products or nutraceuticals in the food industry. This contribution presents an overview of nutraceutical effects and potential health benefits of SPs derived from marine algae. [Copyright &y& Elsevier]

Highlights: [•] Two peptides LDAVNR and MMLDF were purified from enzymatic hydrolysate of Spirulina maxima. [•] These peptides are effective against histamine production from mast cells. [•] These peptides significantly suppress cytokine generation from endothelial cells. [•] These peptides inhibit ROS production from mast cells and endothelial cells. [•] LDAVNR and MMLDF are functional peptides with potent anti-inflammatory benefits. [Copyright &y& Elsevier]

Abstract: Functional food is considered to be any food or food component that provides health benefits beyond basic nutrition. Recently, a great deal of interest has been paid by the consumers towards natural bioactive compounds as functional ingredients in the diets due to their various health beneficial effects. Notably, marine resources have been recognized as rich sources of structurally diverse biologically active compounds with great application potential in marine functional foods. Among them, fucoidans have been found to possess various bioactivities including antioxidant, anti-inflammatory, anti-allergic, anti-tumor, anti-obesity, anti-coagulant, anti-viral, anti-hepatopathy, anti-uropathy, and anti-renalpathy effects. Hence, this contribution focuses on fucoidans derived from marine sources and presents a brief overview of their biological activities with health benefits. [Copyright &y& Elsevier]

Abstract: Marine microbes have been a storehouse of bioactive metabolites with tremendous potential as drug candidates. Marine microorganism derived secondary metabolites (chemical compounds/peptides) are considered to be a burning area of research since recent past. Many of such compounds have been proven to be anti-bacterial, anti-fungal, anti-algal, anti-HIV, anti-helminthic, anti-protozoan, anti-tumor and anti-allergic agents. Marine bacteria and fungi have been reported to be the producers of such compounds owing to their defense mechanisms and metabolic by products. Although the number of natural products isolated from these classes of marine microbial flora is large, a limited number of such compounds reach the clinical trial and even less number of them get approved as a drug. Here we discuss the recent studies on the isolation, characterization and the pharmacological significances of anti-bacterial, anti-fungal and anti-infective agents of marine microbial origin. Further, the clinical status of such compounds has also been discussed in comparison with those derived from their terrestrial counterparts. [Copyright &y& Elsevier]

Abstract: Recently, the isolation and characterization of the biologically active components from seaweeds have gained much attention from various research groups across the world. The marine algae have been studied for biologically active components and phlorotannins are one among them. Among marine algae, brown algal species such as Ecklonia cava, Eisenia arborea, Ecklonia stolinifera and Eisenia bicyclis have been studied for their potential biological activities. Majority of the investigations on phlorotannins derived from brown algae have exhibited their potentiality as antioxidant, anti-inflammatory, antidiabetic, antitumor, antihypertensive, anti-allergic, hyaluronidase enzyme inhibition and in matrix metalloproteinases (MMPs) inhibition activity. In this review, we have made an attempt to discuss the potential biological activities of phlorotannins from marine brown algae and their possible candidature in the pharmaceutical applications. [Copyright &y& Elsevier]

Abstract: The importance of marine algae as sources of functional ingredients has been well recognized due to their valuable health beneficial effects. Therefore, isolation and investigation of novel ingredients with biological activities from marine algae have attracted a great deal of attention. Among functional ingredients identified from marine algae, natural pigments (NPs) have received particular attention. These NPs exhibit various beneficial biological activities such as antioxidant, anticancer, anti-inflammatory, anti-obesity, anti-angiogenic and neuroprotective activities. This contribution focuses on biological activities of marine algae-derived NPs and emphasizing their potential applications in foods as well as pharmaceuticals areas. [Copyright &y& Elsevier]

Abstract: Chitosan gallate were synthesized using a free radical-induced grafting reaction. Chitosan gallate showed enhanced water-solubility compared to plain chitosan, and exhibited good thermal stability. The IC50 value of chitosan gallate against 2,2-diphenyl-1-picrylhydrazyl (DPPH) was 17.86μg/mL. In addition, chitosan gallate effectively inhibited the generation of intracellular reactive oxygen species (ROS), and also suppressed lipid peroxidation in RAW264.7 macrophage cells. Chitosan gallate also exhibited the protection effect on genomic DNA damage by induced hydroxyl radical, and up-regulated the protein expression of antioxidant enzymes including superoxide dismutase-1 and glutathione reductase under H2O2-mediated oxidative stress in RAW264.7 macrophage cells. These results indicate that chitosan gallate might be potential antioxidant biomaterials. [Copyright &y& Elsevier]

Abstract: This paper discusses acetylcholinesterase inhibitory properties of gallic acid-grafted-chitosans (GA-g-chitosans) with different grafting ratios. The GA-g-chitosans exhibited potent acetylcholinesterase inhibitory effects in a dose-dependent manner, and their IC50 values ranged from 138.5±0.25 to 397.6±5.2μg/mL. The acetylcholinesterase inhibition kinetics of the GA-g-chitosan (I) by Lineweaver–Burk plots showed a decrease in V max, whereas K m was not altered, thus suggesting a non-competitive mode of inhibition. The inhibition constant, K i, was found to be 64.85μg/mL by the secondary plot of the Lineweaver–Burk plots. In addition, the GA-g-chitosan (I) did not exert any significant cytotoxicity against PC12 cells, and the cellular acetylcholinesterase activity in PC12 cells was significantly inhibited by the GA-g-chitosan (I). This is the first report on acetylcholinesterase inhibition by the grafting of GA onto chitosan, and this compound might be helpful in preventing Alzheimer''s disease by elevating cholinergic transmission. [Copyright &y& Elsevier]

Abstract: Gallic acid-grafted-chitosans (GA-g-chitosans) with four different grafting ratios were prepared by a free radical-induced grafting reaction in order to improve antioxidant and water-solubility. To verify the synthesis of GA-g-chitosans, 1H NMR and thin layer chromatography were employed, and the results revealed that GA was grafted onto the chitosan. The antioxidant properties of the GA-g-chitosans were evaluated using several in vitro models. GA-g-chitosan (I), which has the highest GA content, showed 92.26% scavenging activity against 2,2-diphenyl-1-picrylhydrazyl and 93.15% hydrogen peroxide scavenging activity at 50μg/mL. GA-g-chitosan (I) was also showed higher reducing power compared to others. All GA-g-chitosans showed improved antioxidant capacities compared to plain chitosan treated in the same conditions without gallic acid grafting. Furthermore, the GA-g-chitosans also exhibited good cytocompatibility and effectively inhibited the formation of intracellular reactive oxygen species (ROS) in time- and dose-dependent manner in RAW264.7 macrophages. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to investigate the inhibitory effect of phloroglucinol on oxidative stress and inflammation. Phloroglucinol is a monomer of phlorotannins abundant in brown algae. A few effects of phloroglucinol have been reported, but any information on its effect on anti-inflammation related to oxidative stress has not been reported in detail until now. In our study phloroglucinol exhibited inhibitory effects not only on oxidative stress but also on the production of inflammatory mediators such as tumor necrosis factor-α, interleukin-1β, interleukin-6 and prostaglandin E2 in RAW264.7 cells stimulated by lipopolysaccharide. Furthermore, in HT1080 cells, a human fibrosarcoma cell line, phloroglucinol decreased the expression of matrix metalloproteinase that play an important role in chronic inflammation. In the presence of phloroglucinol NF-κB transcription factor that regulates the expression of these inflammatory mediators was inactivated via inhibition of NIK, and activation of AP-1 transcription factor was also reduced via inactivation of ERK, a MAPK. These results suggest that phloroglucinol can provide a therapeutic potential for prevention of chronic inflammation. [Copyright &y& Elsevier]

Abstract: Dioxinodehydroeckol (DHE) isolated from Ecklonia cava, has previously been investigated for its inhibition of the differentiation of 3T3-L1 preadipocytes into adipocytes. Levels of lipid accumulation were measured, along with changes in the expression of genes and proteins associated with adipogenesis and lipolysis. Confluent 3T3-L1 preadipocytes in medium with or without different concentrations of DHE for 7 days were differentiated into adipocytes. Lipid accumulation was quantified by measuring direct triglyceride contents and Oil-Red O staining. The expression of genes and proteins associated with adipogenesis and lipolysis was measured using RT-PCR, quantitative real-time RT-PCR and Western blotting analysis. It was found that the presence of DHE significantly reduced lipid accumulation and down-regulated the expression of peroxisome proliferator-activated receptor-γ (PPARγ), sterol regulatory element-binding protein 1 (SREBP1) and CCAAT/enhancer-binding proteins (C/EBPα) in a dose-dependent manner. Moreover, DHE suppressed regulation of the adipocyte-specific gene promoters such as fatty acid binding protein (FABP4), fatty acid transport protein (FATP1), fatty acid synthase (FAS), lipoprotein lipase (LPL), acyl-CoA synthetase 1 (ACS1), leptin, perilipin and HSL compared to control adipocytes. The specific mechanism mediating the effects of DHE was confirmed by activation of phosphorylated AMP-activated protein kinase (pAMPK). Therefore, these results suggest that DHE exerts anti-adipogenic effect on adipocyte differentiation through the activation and modulation of the AMPK signaling pathway. [Copyright &y& Elsevier]

Abstract: In the present study, a peptide possessing antioxidant properties was isolated from Nile tilapia (Oreochromis niloticus) scale gelatin. Gelatin protein was hydrolyzed using alcalase, pronase E, trypsin and pepsin. Antioxidant efficacy of respective hydrolysates were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical and superoxide radical anion scavenging activities. Moreover, protective effect on DNA damage caused by hydroxyl radicals generated was determined. Further, the level of reactive oxygen species (ROS) was determined using a fluorescence probe, 2′,7′-dichlorofluorescin diacetate (DCFH-DA), which could be converted to highly fluorescent dichlorofluorescein (DCF) with the presence of intracellular ROS on mouse macrophages, RAW 264.7 cells. Among hydrolysates, alcalase-derived hydrolysate exhibited the highest antioxidant activity compared to other enzymatic hydrolysates. Therefore, it was further analyzed and the sequence of an active peptide present in it was identified as Asp-Pro-Ala-Leu-Ala-Thr-Glu-Pro-Asp-Pro-Met-Pro-Phe (1382.57Da). This peptide showed no cytotoxic effect on mouse macrophages (RAW 264.7) and human lung fibroblasts (MRC-5). In addition, it scavenged hydroxyl, DPPH and superoxide radicals at the IC50 values of 7.56, 8.82 and 17.83μM, respectively. These results suggest that the peptide derived from Nile tilapia (O. niloticus) scale gelatin acts as a candidate against oxidative stress and could be used as a potential functional food ingredient. [Copyright &y& Elsevier]

Abstract: Marine organisms are rich sources of structurally diverse bioactive compounds. Recently, a great deal of interest has been expressed regarding marine-derived bioactive peptides because of their numerous health beneficial effects. Moreover, many studies have reported that marine bioactive peptides can be used as antihypertensive, antioxidative, anticoagulant, and antimicrobial components in functional foods or nutraceuticals and pharmaceuticals due to their therapeutic potential in the treatment or prevention of diseases. This contribution presents an overview of the bioactive peptides derived from marine organisms and their biological activities with potential applications in different areas. [Copyright &y& Elsevier]

Abstract: A potent anticoagulant oligopeptide was isolated from the edible parts of blue mussel (Mytilus edulis). M. edulis anticoagulant peptide (MEAP) with an approximately 2.5kDa molecular mass was similar to the amino acid sequence of the EF-hand domain of calmodulin from scallop adductor muscle. MEAP could potently prolong both the thrombin time and the activated partial thromboplastin time, and specifically interact with blood coagulation factors: FIX, FX, and FII. MEAP could inhibit proteolytic activation of FX by the intrinsic FXase and formation of FIIa by a prothrombinase complex in dose-dependant reactions. This study elucidated that MEAP prolonged blood clotting by inhibiting activation of FX in the intrinsic tenase complex (FIXa/VIIIa/PLs) and conversion of FII to FIIa in the prothrombinase complex (FXa/FVa/PLs). [Copyright &y& Elsevier]

Abstract: The inhibitory effects of phlorotannins isolated from Ishige okamurae on cholinesterase (acetylcholinesterase and butyrylcholinesterase) were evaluated. The methanolic (MeOH) extract and ethyl acetate (EtOAc) soluble fraction obtained from I. okamurae exhibited inhibitory effects against cholinesterase. Repeated column chromatography of the EtOAc fraction of I. okamurae resulted in the isolation of three phlorotannins. Their structures were elucidated on the basis of spectroscopic techniques (1D and 2D NMR) and characterized as phloroglucinol (1), 6,6′-bieckol (2) and diphlorethohydroxycarmalol (3), respectively. Among these, compound 2 exhibited inhibitory activity against acetylcholinesterase (AChE), with IC50 of 46.42±1.19μM. Compound 3 showed a moderate butyrylcholinesterase (BChE) inhibitory activity with IC50 value of 110.83±1.15μM. Compound 2 displayed noncompetative type inhibition against AChE when analyzed by Lineweaver–Burk plots of the inhibition kinetics. Thus, we suggest that compound 2 and I. okamurae, serve as a potential AChE inhibitors that could be used as potential functional food ingredients or nutraceuticals for preventing Alzheimer’s disease. [Copyright &y& Elsevier]

Abstract: The purpose of this research is not only to produce two kinds of chitin oligosaccharides or N-acetyl chito-oligosaccharides (NA-COSs) with different molecular weights (MW) from crab chitin hydrolysis solution but also to determine their effect against oxidative stress in live cells. Two kinds of NA-COSs with MW 1–3kDa (NA-COS 1–3kDa) and below 1kDa (NA-COS<1kDa) were obtained using an ultrafiltration membrane system. They exhibited an inhibitory effect against DNA and protein oxidation. In addition, in their presence, intracellular glutathione (GSH) level and direct intracellular radical scavenging effect were significantly increased in a time-dependent manner in mouse macrophages (RAW 264.7) and rendered inhibitory effect against cellular oxidative stress. In particular, NA-COS 1–3kDa was more effective than NA-COS<1kDa in protein oxidation and production of intracellular free radicals in live cells. These results suggest that NA-COSs act as a potential scavenger against oxidative stress in cells. [Copyright &y& Elsevier]

Abstract: Ecklonia cava (EC) is a brown alga that evidences radical scavenging activity, bactericidal activity, tyrosinase inhibitory activity, and protease inhibitory activity. However, its anti-allergic effects remain poorly understood. In the current study, we attempted to determine whether pretreatment with EC induces a significant inhibition of asthmatic reactions in a mouse asthma model. Mice sensitized and challenged with ovalbumin (OVA) evidenced typical asthmatic reactions, as follows: an increase in the number of eosinophils in bronchoalveolar lavage fluid; a marked influx of inflammatory cells into the lung around blood vessels and airways, and airway luminal narrowing; the development of airway hyperresponsiveness; the detection of tumor necrosis factor-alpha (TNF-α) and Th2 cytokines, including IL-4 and IL-5 in the bronchoalveolar lavage (BAL) fluid; and the detection of allergen-specific immunoglobulin E (IgE) in the serum. However, the administration of EC extract prior to the final airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. We also demonstrated that EC extracts treatment resulted in significant reductions on matrix metalloproteinase-9 (MMP-9) and Suppressor of cytokine signaling-3 (SOCS-3) expression and a reduction in the increased eosinophil peroxidase (EPO) activity. The treatment of animals with EC extracts resulted in a significant reduction in the concentrations of the Th2 cytokine (IL-4 and IL-5) in the airways, without any concomitant increase in the concentration of Th1 cytokines. These findings indicate that EC extracts may prove useful as an adjuvant therapy for allergic airway reactions via the inhibition of the Th2 response. Accordingly, this study may provide evidence that EC extract performs a critical function in the amelioration of the pathogenetic process of asthma in mice. [Copyright &y& Elsevier]

Abstract: Chitosans with different degree of deacetylation were prepared from crab shell chitin in the presence of alkali. Aminoderivatized chitosan derivatives were prepared in addition of amino functional groups at a hydroxyl site in the chitosan backbone. Six kinds of aminoderivatized chitosan such as aminoethyl-chitosan (AEC90), dimethylaminoethyl-chitosan (DMAEC90), and diethylaminoethyl-chitosan (DEAEC90), which were prepared from 90% deacetylated chitosan, and AEC50, DMAEC50 and DEAEC50, which were prepared from 50% deacetylated chitosan, were prepared and their reactive oxygen species (ROS) scavenging activities were investigated against hydroxyl radical, superoxide anion radical and hydrogen peroxide. The electron spin resonance (ESR) spectrum revealed that AEC90 showed the highest scavenging effects against hydroxyl and superoxide anion radical, the effects were 91.67% and 65.34% at 0.25 and 5mg/mL, respectively. For hydrogen peroxide scavenging effect, DEAEC90 exhibited the strongest activity. These results suggest that the scavenging effect depends on their degree of deacetylation and substituted group. [Copyright &y& Elsevier]

Abstract: Generation of immense quantity of underutilized marine processing byproducts has long been recognized as wastes and greater efforts were given to use these materials in various applications. With a great number of researches on these byproducts, some biologically active compounds were identified and applicated to the useful compounds for human utilization. Potential applications of proteins, lipids, chitin and minerals in marine bioprocessing leftovers as bioactive materials have increased the value of processing byproducts in recent years. In this review, we have focused on the utilization of marine processing byproducts to screen bioactive compounds and their potential applications. [Copyright &y& Elsevier]

Abstract: Novel water-soluble chitin derivative was prepared by chemical modification to evaluate antioxidant activities by free radical scavenging potential using electron spin resonance spin trapping technique. Aminoethyl-chitin (AEC) exhibited free radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, superoxide, and peroxyl radicals. AEC quenched DPPH and peroxyl radical over 55% and 59% at 4mg/mL, and also suppressed superoixde radical over 58% at 2mg/mL. Especially, AEC was more active against hydroxyl radical, and scavenging ratio was 92.2% at 0.12mg/mL. These results suggested that free amino group in the –CH2CH2NH2 plays an important role in the free radical scavenging activity. In addition, cytotoxic effect of AEC was assessed using human lung fibroblast (MRC-5) cell line, and AEC showed less toxic against MRC-5. [Copyright &y& Elsevier]

Abstract: Many researchers have focused chitosan as a source of potential bioactive material during past few decades. However, chitosan has several drawbacks to be utilized in biological applications, including poor solubility under physiological conditions. Therefore, a new interest has recently been emerged on partially hydrolyzed chitosan, chitosan oligosaccharides (COS). During the resent past, several technological approaches have been taken to prepare COS and, enzymatic preparation methods captured a great interest due to safe and non-toxic concerns. With time, new improvements were introduced to enzymatic production and presently it has been developed to a continuous production process. Many of the biological activities reported for COS, such as antimicrobial, anticancer, antioxidant, and immunostimulant effects are depend on their physico-chemical properties. In this review, we have summarized different enzymatic preparation methods of COS and some of their reported biological activities. [Copyright &y& Elsevier]