Scallop Extracts Research Articles

Procjena utjecaja matriksa na kvantifikaciju lipofilnih toksina u plodovima mora

Phycotoxin accumulation in seafood can cause human intoxication and significant economic losses in seafood-producing areas. To protect consumer safety, maximum permitted levels in bivalve molluscs have been set, with appropriate analytical methods for their determination and quantification. The reference method for lipophilic phycotoxins, commonly referred to as lipophilic toxins, is liquid chromatography tandem mass spectrometry (LCMS/MS method), where coeluting components from the matrix can affect the efficiency of ionisation, resulting in erroneous quantification. In this study, the matrix effect was evaluated using the slope ratio analysis method, which involves comparing the slopes of the calibration curves in the matrix with those in pure solvent. The extent of the matrix effect was investigated in mussels, oysters, queen scallops and ascidians. The study covered all phycotoxins under Regulation EU 853/2004 for which certified standards are commercially available, including unregulated pectenotoxin 2. The results indicated that all lipophilic toxins were susceptible to this effect when LC-MS/MS was used for their determination. Significant ion suppression was evident for most analytes in all matrices, except for okadaic acid and dinophysistoxin 2 in bivalves, where significant ion enhancement was demonstrated, and dinophysistoxin 1 in oyster and scallop extract where no significant effect on ionisation was observed. Further analysis revealed no significant differences between the slope of mussel matrix-matched calibration and that of other bivalve matrices. Given this minor difference, the mussel matrix-matched calibration curve could be applied to minimise the matrix effect and to quantify phycotoxins in bivalve matrices analysed here, with the exception of the okadaic acid group in ascidians, which requires matrix-matched calibration prepared with the blank extract of these mentioned species. Given the risks phycotoxins pose to human health, ongoing analytical method development is necessary in this field to properly control food safety and ensure consumer health.

The Effect of Lactiplantibacillus plantarum I-Enriched Diet on the Phenolic Content and Antioxidant Capacity of Queen Scallop (Aequipecten opercularis Linnaeus, 1758) Extracts.

The use of probiotics in the diet of bivalves poses a great potential in aquaculture as an alternative to antibiotics. The aim of this study was to assess the effect of Lactiplantibacillus plantarum I on the phenolic content and antioxidant capacity (AC) of queen scallop extracts after one month of feeding. Total phenols (TP) ranged from 28.17 ± 3.11 to 58.58 ± 8.57 mg GAE/100 g, total non-flavonoids (TNF) from 23.33 ± 3.66 to 36.56 ± 9.91 mg GAE/100 g, and total flavonoids (TF) from 10.56 ± 5.57 to 30.16 ± 1.69 mg CE/100 g. AC was assessed via three different methods: the ferric-reducing ability of plasma assay (FRAP), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic) acid assay (ABTS), and 2,2-diphenyl-1-picryhydrazyl assay (DPPH). FRAP values ranged from 0.13 ± 0.03 to 0.17 ± 0.02 µM AA/g, ABTS from 0.68 ± 0.11 to 2.79 ± 0.34 µM AA/g, and DPPH from 1.75 ± 0.17 to 2.98 ± 0.53 µM AA/g. Among all extracts, the best phenolic content and AC were observed in water extracts from queen scallops. The bivalves treated with the Lactiplantibacillus plantarum I-enriched diet showed higher AC according to the FRAP assay in all extracts. A significant correlation was observed between AC and TP and TNF in control and Lactiplantibacillus plantarum I-treated scallops.

Investigation of the effect of natural astaxanthin on cytotoxicity of mesenchymal stromal cells

The search for new promising dental products that have anti-inflammatory, wound-healing, antibacterial and immunomodulatory effects and at the same time exhibit minimal side effects is quite an urgent task of modern scientific and practical medicine. As part of this work, we have produced four samples of an antioxidant dental gel containing natural astaxanthin. Astaxanthin, which is part of the dental gel, by its chemical structure belongs to the class of carotenoids and is a natural antioxidant present in various amounts in living organisms.
 The first gel sample we made consisted of natural astaxanthin. An additional substance of the second sample of the preventive gel was interferon [12]. Interferon α has the ability to stimulate the phagocytic activity of macrophages, as well as the cytotoxic activity of T cells and NK cells. It has an indirect antiviral effect, increasing the body’s resistance to viral infections and modulating the immune system’s response aimed at neutralizing viruses or destroying infected cells. The third sample of dental gel contained polyprenol. Polyprenols are precursors of the most important transport lipid of all living organisms, dolichol. Since 2012, polyprenols have been included in the list of the most important essential components of nutrition for normal life support. Polyprenols are included in the list of vital components for the human body, as they are the building material for damaged cells. They help to stabilize cell membranes and restore cells of the brain, heart, liver and other organs, stimulate energy exchange and regenerative potential of body tissues. Polyprenols interact perfectly with antioxidants, increasing the efficiency of their work. The fourth sample included scallop extract as an enhancer of natural astaxanthin.
 Objective: to evaluate the effect of antioxidant gel on the survival and proliferation of mesenchymal stromal cells (MSCs) of the human umbilical cord.
 Materials and methods. Antioxidant gel with astaxanthin, astaxanthin with interferon, astaxanthin with polyprenol and astaxanthin with scallop extract were examined for the viability of MSCs in the MTT test and in the PI test.
 Results. The antioxidant gel with interferon and polyprenol has a proliferative effect on MSCs compared to control samples, which confirms its potential of side effects, antitoxic and wound healing effect. When studying the induction of apoptosis, we found that the percentage of apoptotic cells according to the PI test did not differ from the cells of the control group, which may indicate the absence of apoptosis-inducing effect of drugs on mesenchymal stromal cells.
 Conclusion. Studying the effects of the developed preventive antioxidant gel with astaxanthin, astaxanthin and interferon, astaxanthin and polyprenol, astaxanthin and scallop extract on the stromal cells of the human umbilical cord, no toxic and side effects were recorded.

Application of biologically active substances from marine hydrobionts in the treatment of age-related macular degeneration

Aim. To evaluate the effectiveness of products obtained from marine aquatic organisms in the treatment of age-related macular degeneration (AMD).Methods. In total, 90 patients diagnosed with AMD of various stages were examined. The control group (30 people) received a vitamin-mineral complex containing carotenoids – lutein and zeaxanthin (Retinorm). The 2nd group of patients (30 people) received the Scallop Extract product. The 3rd group of patients (30 people) received the Ascidia Oil Extract in combination with the basic therapy. All patients underwent a comprehensive ophthalmological examination, including optical coherence tomography of the macula and perimetry. The examination was carried out prior to and two weeks after treatment completion.Results. The experimental group of patients receiving Scallop Extract showed a significant increase in visual acuity indicators after treatment completion. For comparison, the experimental groups of patients receiving Ascidia Oil Extract demonstrated improved photosensitivity indicators and reduced visual field defects.Conclusions. Addition of marine hydrobiont-based products to the basic AMD therapy is pathogenetically justified due to its positive effects on the maintenance and improvement of visual functions, as well as the light sensitivity of the retina.

Identification and Quantitation of Taste-Active Compounds in Dried Scallops by Combined Application of the Sensomics and a Quantitative NMR Approach.

Application of the sensomics concept on dried scallops, a Japanese specialty produced from the adductor muscle of scallops, revealed after activity-guided fractionation with subsequent (comparative) taste dilution analyses besides nucleotides, amino acids, organic acids, and inorganic ions, the presence of taste-modulating quaternary ammonium compounds and opines in highly taste-active fractions. In order to recreate the taste of dried scallops, two independent quantitation approaches were applied and compared. The first approach used multiple targeted UHPLC-MS/MS and high-performance ion chromatography methods. Besides already established quantitation methods for basic taste compounds, a new HILIC-UHPLC-MS/MSMRM method for the quantitation of chromatographically challenging opines, using synthesized stable isotope-labeled standards, was developed. Furthermore, a qHNMR approach was applied, enabling a direct identification and quantitation of organic taste compounds in a food extract without prior fractionation using a reference 1H NMR database. Both methods yielded similar quantitative results of taste-active compounds in dried scallop extracts and subsequent taste recombination experiments based on these data were able to recreate the taste of dried scallops.

Antioxidant Potential of Madura Knife Scallop (Solen sp) Extract as a Prevention of Oxidative Stress

Reactive Oxygen Species (ROS) are produced by humans as a result of cellular metabolism and environmental factors such as pollutants or cigarette smoke. ROS is a very reactive molecule and has the ability to damage cell structure. Oxidative stress is a condition between oxidants and antioxidants that is not balance, pathophysiologically, oxidative stress can trigger the risk of various diseases including hypertension, atherosclerosis, diabetes, heart failure, stroke and other chronic diseases. Oxidative stress can be overcome by intake of antioxidants. The purpose of this study was to determine the antioxidant activity contained in the meat and shells of a knife scallop (Solen sp.) that lives in Bangkalan waters, Madura. The method used in this study is an analysis of antioxidant activity with the DPPH method. Knife scallop has antioxidant activity which is evident from the IC50 values obtained. IC50 values of the shell and meat extract with ethanol solvent were 489.56 ppm and 748.49 ppm. IC50 values of the shell and meat extract with ethyl acetate solvent were 916.43 ppm and 2045.93 ppm. While the IC50 value of the shell and meat extract with chloroform solvent was 119.37 ppm and 1692.80 ppm. Based on IC50 data of knife scallop shell and meat extracts on the 3 types of solvents, it can be concluded that knife scallop’s shell and meat extract with ethanol solvent has the greatest antioxidant activity compared to ethyl acetate and chloroform solvents.

Indirect quantitation of saxitoxin by HPLC with post-column oxidation and fluorometric detection.

The indirect identification and quantification of saxitoxin (STX) using other STX analogues by high-performance liquid chromatography with post-column oxidation and fluorescent detection (HPLC-FD) was investigated. Decarbamoylsaxitoxin (dcSTX) among the many STX analogues was selected as an external standard to identify and quantify STX. The retention time of STX in shellfish extracts by HPLC-FD was reproducibly estimated by using the retention time of dcSTX and the separation factor (α) between STX and dcSTX. Almost all of the columns tested to setup the method were useful to identify STX. Because a molar fluorescent coefficient of dcSTX was slightly different from that of STX, a factor used to correct the fluorescent coefficient in STX/dcSTX was determined to be 1.30. The indirect quantification of STX in scallop extracts by using the correction factor agreed to 80 - 100% precision with direct quantification using STX as an external standard.

High-throughput receptor-based assay for the detection of spirolides by chemiluminescence

The spirolides are marine toxins that belong to a new class of macrocyclic imines produced by dinoflagellates. In this study a previously described solid-phase receptor-based assay for the detection of spirolides was optimized for high-throughput screening and prevalidated. This method is based on the competition between 13-desmethyl spirolide C and biotin-α-bungarotoxin immobilized on a streptavidin-coated surface, for binding to nicotinic acetylcholine receptors. In this inhibition assay the amount of nAChR bound to the well surface is quantified using a specific antibody, followed by a second anti-mouse IgG antibody labeled with horseradish peroxidase (HRP). The assay protocol was optimized for 384-well microplates, which allowed a reduction of the amount of reagents per sample and an increase of the number of samples per plate versus previously published receptor-based assays. The sensitivity of the assay for 13-desmethyl spirolide C ranged from 5 to 150 ng mL−1. The performance of the assay in scallop extracts was adequate, with an estimated detection limit for 13-desmethyl spirolide C of 50 μg kg−1 of shellfish meat. The recovery rate of 13-desmethyl spirolide C for spiked samples with this assay was 80% and the inter-assay coefficient of variation was 8%. This 384-well microplate, chemiluminescence method can be used as a high-throughput screening assay to detect 13-desmethyl spirolide C in shellfish meat in order to reduce the number of samples to be processed through bioassays or analytical methods.

Determination of γ-glutamyl-valyl-glycine in raw scallop and processed scallop products using high pressure liquid chromatography-tandem mass spectrometry.

The determination of the kokumi peptide, γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) in raw scallop and processed scallop products was carried out using high pressure liquid chromatography-tandem mass spectrometry (LC/MS/MS). The detection of γ-Glu-Val-Gly was achieved using a multiple reaction monitoring (MRM) method. The optimised condition enabled the precise determination of γ-Glu-Val-Gly. Raw scallop contained 0.08 μg/g γ-Glu-Val-Gly, and the γ-Glu-Val-Gly levels in processed scallop products, such as dried-scallop and scallop extract, were measured to be 0.64 and 0.77 μg/g, respectively. This is the first report to confirm the existence of γ-Glu-Val-Gly in foodstuff.

Biosensor‐Based Assay for Domoic Acid: Comparison of Performance Using Polyclonal, Monoclonal, and Recombinant Antibodies

Domoic acid (DA) is a potent neuroexcitatory toxin produced by the diatom Pseudonitszchia sp, and causes amnesic shellfish poisoning in humans through the ingestion of contaminated shellfish. Shellfish products placed on the market are, therefore, highly monitored. A panel of anti‐DA antibodies, which included a mouse monoclonal, sheep polyclonal antiserum, and single chain variable region fragments from sheep and chicken, were evaluated for suitability for assay development using the surface plasmon resonance biosensors from BIAcore AB. Kinetic analysis of the binding of each antibody to immobilized DA gave dissociation rates varying from 2.07×10−5 for the sheep polyclonal to 6.52×10−4 for the mouse monoclonal. Inhibition assays were established with each antibody and the variation in sensitivities and lower limits of detection of the standard curves could be predicted from the dissociation rates. The standard curve given by the sheep polyclonal assay was the most sensitive with an ED‐50 (the concentration of DA inhibiting binding by 50%) of 26 ng/mL and the mouse monoclonal the least (ED‐50=1.445 µg/mL). All assays showed a high level of reproducibility. The sheep polyclonal assay was shown to be suitable for determination of domoic acid in scallop extracts.

Sensitization to king scallop (Pectin maximus) and queen scallop (Chlamys opercularis) proteins

To report a case of occupational asthma and urticaria due to the queen scallop (Chlamys opercularis) and king scallop (Pectin maximus). A 40-year-old female worked in a shellfish-processing plant, handling king and queen scallops for 5 years. At the time of investigation, she described a 2-year history of work-related respiratory symptoms. Serial peak expiratory flow rate readings were recorded and an OASYS study completed. A workplace visit was undertaken and specific immunoglobulin (IgE) radioallergosorbent (RAST) testing of scallop extracts was performed. The OASYS study was consistent with occupational asthma. RAST testing demonstrated evidence of specific sensitization (IgE) to queen and king scallop. There was also some cross-reactivity observed with other shellfish (prawns and crabs). Workers exposed to aerosols from scallop species are at risk of occupational asthma and require effective respiratory health surveillance.

Matrix effect and correction by standard addition in quantitative liquid chromatographic–mass spectrometric analysis of diarrhetic shellfish poisoning toxins

An evaluation of the feasibility of liquid chromatography–mass spectrometry (LC–MS) with atmospheric pressure ionization was made for quantitation of four diarrhetic shellfish poisoning toxins, okadaic acid, dinophysistoxin-1, pectenotoxin-6 and yessotoxin in scallops. When LC–MS was applied to the analysis of scallop extracts, large signal suppressions were observed due to coeluting substances from the column. To compensate for these matrix signal suppressions, the standard addition method was applied. First, the sample was analyzed and then the sample involving the addition of calibration standards is analyzed. Although this method requires two LC–MS runs per analysis, effective correction of quantitative errors was found.

Conversion of pectenotoxin-2 to pectenotoxin-2 seco acid in the New Zealand scallop, Pecten novaezelandiae

SUMMARY: Comparison of pectenotoxin (PTX) profiles between the toxic dinoflagellate Dinophysis acuta and scallops Pecten novaezelandiae collected at Wedge Point, Queen Charlotte Sound, New Zealand was carried out by liquid chromatography–mass spectrometry (LC-MS) with turbo-ionspray ionization. Although the major PTX homolog in D. acuta was pectenotoxin-2 (PTX2), the scallops contained pectenotoxin-2 seco acid (PTX2SA) as the predominant toxin. Pectenotoxin-2 isolated from D. acuta was rapidly converted to PTX2SA and its epimer 7-epi-pectenotoxin-2 seco acid (7-epi-PTX2SA) in the scallop extracts. These results indicate that PTX2SA and 7-epi-PTX2SA arose from the conversion of PTX2 by scallop tissue. The results indicate that New Zealand scallops have an ability to reduce the cytotoxicity of PTX2 by conversion to PTX2SA.

Direct evidence of transformation of dinophysistoxin-1 to 7- O-acyl-dinophysistoxin-1 (dinophysistoxin-3) in the scallop Patinopecten yessoensis

Non-toxic scallops Patinopecten yessoensis were reared for 5 days with the toxic dinoflagellate Dinophysis fortii sampled from the sea. The total cell number ingested by five scallops during the feeding experiment was approximately 682×10 3. Okadaic acid (OA), dinophysistoxin-1 (DTX1) and esterified toxins of OA and DTX1 in D. fortii and scallop extracts were determined by liquid chromatography fluorescence detection (LC-FLD) as their 9-anthryldiazomethane (ADAM) derivatives. Only DTX1 was detected in D. fortii extracts used for the feeding experiment. The content of esterified DTX1 in scallops fed on D. fortii was significantly higher than that of DTX1. Identification of esterified DTX1, 7- O-palmitoyl DTX1 (7- O-16:0 DTX1), in D. fortii and scallop extracts was carried out by LC equipped with an atmospheric pressure electrospray ionization–mass spectrometry (ESI–MS). Only extracts of scallops fed on D. fortii yielded a mass spectrum exhibiting abundant [M−H] − at m/ z 1055 corresponding to 7- O-16:0 DTX1. These findings are the first direct evidence of the transformation of DTX1 to 7- O-acyl DTX1 in scallop tissues.

魚介類におけるグルタチオンの分布と呈味効果

Contents of glutathione (GSH) in several fresh seafoods were determined by the HPLC method. GSH was detected in adductor muscle of scallop at a concentration of 29mg/100g and over the taste threshold of GSH (10mg/100ml). GSH content in salmon (9.2mg/100g) was near the threshold value. Other seafoods contained GSH in lower quantities. Contents of GSH disulfide (GSSG) in some seafoods were higher than those of GSH. The flavor character strengthened by GSSG was compared with that of GSH in the umami solution, showing that GSSG did not contribute to the flavors of foods so much as GSH.The effects of adding GSH on the flavor of GSH-free synthetic scallop extract at a concentration of 29mg/100ml were examined by sensory evaluation. GSH increased the intensities of sweetness, umami, and some flavor characteristics, such as thickness, mouthfulness, and continuity, suggesting that GSH contributes to the flavor of scallop.

Potentiation of phototactic suppression in Hermissenda by a chemosensory stimulus during compound conditioning.

Modifications of Hermissenda's phototactic behavior by compound pairings of light, scallop extract, and rotation were assessed. In general, the scallop extract potentiated phototactic suppression. Potentiation was dependent on (a) conjunctive presentations of scallop and light, (b) number of conditioning trials, and (c) scallop extract concentration. In related experiments, no second-order conditioning or sensory preconditioning of phototactic suppression was observed, indicating that within-compound associations did not contribute appreciably to potentiation. These results represent the first detailed analysis of compound conditioning in a mollusk using discrete presentations of well-characterized conditioned stimuli from distinct sensory modalities.

Studies on digestive system and assimilation of a flavored diet in ocellate puffer.

The digestive system in the ocellate puffer was histologically and biochemically examined. Also, the effect of scallop extract as a flavor in a diet on performance of the puffer was investigated.The ocellate puffer lacks a stomach, resulting that its expansion sea observed only esophageal epithelium and expansion sac-epithelium and that pepsin-like activity in the digestive tract from the esophagus to the opening portion of bile duct, excluding the expansion sac, maintained an extremely low level.Performance of the puffer fed the flavored diet for 20 days was much better than that fed the unflavored diet. Better protein digestibility was also recognized in the puffer fed the flavored diets. These findings suggest that favorite chemical stimuli caused by the dietary supplementation of the flavor promot digestive and absorptive functions even in the ocellate puffer having no stomach.

Extractive Components of Scallop and Identification of its Taste-active Components by Omission Test

In order to identify the taste-active components of scallop Patinopecten yessoensis, freeIn order to identify the taste-active components of scallop Patinopecten yessoensis, free and combined amino acids, nucleotides and related compounds, quaternary ammonium bases, organic acids, glycogen, inorganic ions, etc. in the muscle extract were analyzed. High content of glycine and taurine, and a high but somewhat lower content of arginine, alanine and glutamic acid were shown. These five amino acids occupied 97% of the total free amino acids. Besides, considerable amounts of AMP, glycinebetaine, homarine, trigonel- line, trimethylamine oxide and trimethylamine were observed. More than 95% of the total extractive nitrogen was accounted for by these nitrogenous constituents. The succinic acid content was very low, while a large amount of glycogen was detected. As for inorganic ions, Na+, Kt+, Cl- and PO43- were major components. After confirming sensorially that the synthetic extract prepared with pure chemicals in accordance with the analytical data except glycogen and combined amino acids could reproduce the taste of the scallop extract fairly well, we carried out omission tests and found that glycine, glutamic acid, alanine, arginine, AMP, Na+, K+ and Cl- were taste-active.

Antitumor of a boiled scallop extract.

A fraction from a boiled scallop extract modified by a sonication procedure exhibited marked antitumor activity when it was injected intradermally into either ICR or C3H/He mice that had been given sc implants of sarcoma 180 and Ehrlich carcinoma. The active moiety was heat-stable and noncytotoxic. In contrast, preparations from raw scallop showed lower antitumor activity and were heat-labile.