High-performance Liquid Chromatography Detection Research Articles

Norcantharidin Nanostructured Lipid Carrier (NCTD-NLC) Suppresses the Viability of Human Hepatocellular Carcinoma HepG2 Cells and Accelerates the Apoptosis.

Malignant tumors have become the main cause of harm to human life and health. Development for new antitumor drugs and the exploration to drug carriers are becoming the concerned focus. In this study, we exploited our experiments to explore the effect of NCTD-NLC on liver cancer cells: the HepG2 cells cultured in vitro were given with NCTD-NLC administration; then, the estimation on cellular proliferation and apoptosis was accomplished through MTT and flow cytometry. Six hours after the administration, we performed the High Performance Liquid Chromatography (HPLC) detection to estimate the NCTD content in the heart, liver, spleen, lung, kidney and plasma of rats. Then, our outcomes showed that NCTD-NLC had a notable inhibitory effect on HepG2 cells, leading to a gradually decreased cellular viability. Cell viability was negatively correlated with NCTD-NLC concentration. Along with the concentration increasing, significantly increasing cellular apoptosis and gradually decreasing cellular viability were observed. The apoptosis rate was positively correlated with the concentration of NCTD-NLC. On the basis of the data we obtained, we found that the group with NCTD-NLC tail vein injection had an obvious advantage in drug delivery when compared with other groups. Through the tumorigenesis test to nude mice, we found that the tumor inhibition rate of the NCTD-NLC tail vein injection group had a 27.48% elevation in contrast to the NCTD gavage group, and it was also the group with the best tumor inhibition efficiency. In conclusion, the NCTD-NLC prepared in this study had a mighty inhibitory effect towards HepG2 cellular viability and an accelerating work on apoptosis. Tail vein injection of NCTD-NLC has the best drug delivery effect.

Rapid Determination of Vitamin D3 in Aquatic Products by Polypyrrole-Coated Magnetic Nanoparticles Extraction Coupled with High-Performance Liquid Chromatography Detection.

A method using polypyrrole-coated Fe3O4 (Fe3O4@PPy composites) based extraction coupled with high performance liquid chromatography was developed for adsorption and detection of trace vitamin D3 (VD3) in aquatic products. The fabricated Fe3O4@PPy composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Fe3O4@PPy composites showed efficient adsorption of VD3 at pH 9.0 and 25 °C with a dose of 25 mg per 10 mL of sample solution and an adsorption time of 11 min. Methanol was selected as the desorption solvent to recover VD3 from Fe3O4@PPy composites after 3 min of static treatment. Fe3O4@PPy composites can be used for VD3 adsorption at least two times. The developed method showed a good linearity for VD3 determination in the range of 0.1–10 μg/mL with a correlation coefficient of 0.9989. The limits of detection and quantification were 10 ng/mL and 33 ng/mL, respectively. The recovery of VD3 in a spiking test was 97.72% with a relative standard deviation value of 1.78%. The content of VD3 in nine aquatic products was determined with this method. Our results show that Fe3O4@PPy composites provide a convenient method for the adsorption and determination of VD3 from the complex matrix of aquatic products.

Detection of Pyrethroids in Food by Immunofluorescence Enhanced Method Based on Three-Layer Core-Shell Structure Upconversion Materials.

A novel rare earth upconversion nanomaterial with a three-layer sandwich core–shell structure was synthesized by an improved thermal decomposition method, and the morphology, fluorescence intensity and diffraction peak position of the new material were characterized by TEM (transmission electron microscope), XRD (Powder X-ray diffraction)and fluorescence spectrophotometer. The inert core/active shell/inert shell design improved the upconversion luminous efficiency of the new material several times. FTIR (Fourier transform infrared spectroscopy)characterization showed that the surface of activated upconversion nanoparticles was modified with silicon shell and amino group. Combined with the characteristics that aminoated polystyrene magnetic microspheres could be separated by the magnetic field, an upconversion magnetic separation immunoassay method for the detection of pyrethroid pesticide residues was established. The capture probe competed with the pyrethroid standard, combined the signal probe, and measured the fluorescence signal value formed by the capture probe signal probe complex at 542 nm under 980 nm excitation light. The LOD (limit of detection)of fenpropathrin was 0.01 μg/L, cypermethrin was 0.015 μg/L, and fenvalerate was 0.011 μg/L. Through the actual sample detection of apple, cabbage and other samples, the recovery rate of pyrethroids was between 83.4~97.8%. The comparison with the HPLC (high performance liquid chromatography)detection results showed that the established method had good accuracy, and could realize the quantitative analysis of pyrethroids in food.

Development of mini column experiments (MCE) by coupling microliter flow HPLC with ICP-MS for the analysis of metal retention under conditions close to nature

The development and implementation of mini column experiments (MCE) can be of great importance to improve existing analytical methods such as highly standardised but unrealistic batch laboratory experiments or lengthy long-term diffusion experiments to study metal sorption/desorption properties. One envisaged application would be to test the retention of repository-relevant metals in claystone, which is a promising candidate for the host rock of a final repository site for high-level radioactive waste (HLW). The used MCE setup is derived from classical high performance liquid chromatography (HPLC). On this basis, coupling of MCE to ICP-MS (inductively coupled plasma mass spectrometry) detection was realised. This online separation enables the dynamic monitoring of metal sorption and desorption experiments on clay minerals (kaolinite), natural clay (Opalinus Clay) and mixtures with quartz sand in background solutions close to nature, and without the common use of metal complexing ligands, other reaction partners or buffers for the analysed metal ions. The optimised method allows the analysis of the retention of various contaminants in real groundwater solutions and compact clay samples in a reasonable amount of time and a small amount of sample. In addition, the coupling to the unspecific mass detector of ICP-MS enables the study of different radionuclides and homologues rather than the limited UV detection of a common HPLC.

Selective solid-phase extraction of atrazine from agricultural environmental water samples using high permeability nanoporous carbon derived from melamine-based polybenzoxazine followed by HPLC-UV

ABSTRACT For the first time, a highly permeable nanoporous carbon derived from melamine-based polybenzoxazine (NPC-PBZ-m) was used as the solid-phase extraction sorbent for trace analysis of atrazine (ATZ) herbicide in environmental water samples as a pre-treatment to enhance detection for high-performance liquid chromatography. Extraction performance was investigated using an agricultural field matrix-water sample. The parameters affecting the solid-phase extraction efficiency were carefully investigated. The optimisation conditions were determined as 200.0 mg of sorbent with an adsorption flow rate of 10.0 mL min−1, an elution flow rate of 1.0 mL min−1, and an elution volume of 3.0 mL. Moreover, it was not necessary to adjust the pH of the sample. Under these optimised extraction conditions, good linearity between 5.00 and 30.0 µg L−1 was achieved along with a limit of detection (LOD) of 1.25 µg L−1 and a limit of quantification (LOQ) of 3.79 µg L−1. Furthermore, the reusability of the NPC-PBZ-m column was found up to 8 cycles making it a new cost-effective material for herbicide enrichment. Finally, this developed method was successfully applied to analyse ATZ in water samples from rice fields, fish farms, and natural canal water, with 98–117% relative recoveries. These results indicate that NPC-PBZ-m with our proposed method is feasible and demonstrates its potential application as an effective adsorbent for herbicide enrichment.

Distribution and Influencing Factors of the Sialic Acid Content in the Breast Milk of Preterm Mothers at Different Stages.

Background and AimsThis study aimed to detect breast milk sialic acid (SA) content and the changing pattern, to understand the various stages of breastfeeding SA secretion, and the influence factors of the human milk SA content.MethodsWe recruited mothers and their infants as our subjects. At days 7, 14, 30, 120, and 365 after delivery, the contents of SA in breast milk were collected and detected through Fluorescence Detector-High Performance Liquid Chromatography. The participants completed the baseline questionnaire at ≤day 7 and were followed up at days 30, 120, and 365.ResultsA total of 95 mothers with 122 infants were included in the analysis, including 22 mothers with 22 term infants, 25 mothers with 35 late preterm infants, 31 mothers with 39 very preterm infants, and 17 mothers with 26 extremely preterm infants. Similar to previous findings, the results of the study showed that, compared with breast milk of term mothers at the same period, breast milk of preterm mothers contained more SA at each time node, and the content of SA in breast milk increased with decreasing gestational weeks. Moreover, maternal age, pre-pregnancy BMI, and delivery mode had significant effects on total SA in breast milk, especially for the preterm infant breast milk. Significant negative associations occurred between SA contents and infant growth status, especially in preterm infants.ConclusionsWe have confirmed the previous observations showing that with the prolongation of lactation time, the content of SA in breast milk gradually decreased, and the content of SA in the breast milk of preterm mothers was higher than that of term mothers. In addition, SA content was associated with maternal age, pre-pregnancy BMI, and delivery mode.

β-Ketoenamine-linked covalent organic framework absorbent for online micro-solid phase extraction of trace levels bisphenols in plastic samples.

Covalent organic frameworks with tunable porous crystallinity and outstanding stability have exhibited fascinating pretreatment performance as ideal extraction media. Herein, the β-ketoenamine-linked TpPa-1 synthesized by 1,3,5-triformylphloroglucinol and paraphenylenediamine was employed as the absorbent for online micro-solid phase extraction of trace bisphenols combined with high-performance liquid chromatography detection. A series of characterizations indicated that the TpPa-1 possessed large surface areas, high stability, and hydrophobicity. The main experimental parameters affecting the extraction efficiency were optimized in detail. Compared with four commercial sorbents, the TpPa-1 exhibited superior enrichment capacity for extracting bisphenols. Under the optimum conditions, the established method demonstrated a wide linear range and high sensitivity with the limit of detection ranging from 0.05-0.06 μg/L. Furthermore, the developed method was successfully applied to determine bisphenols in plastic samples. Bisphenol A was actually detected in a transparent box with a concentration of 0.31 μg/g, and the recoveries of the four bisphenols in the plastic samples were 80.5-116% with the relative standard deviation less than 9.2%. Such performance was attributed to recognition affinity, including the π-π affinity, hydrophobic effect, and hydrogen bond. These results demonstrated that TpPa-1 possessed great potential to be an excellent pretreatment medium for online separation and analysis of trace analytes in complex samples.

Review of the Analytical Methods Based on HPLC-Electrochemical Detection Coupling for the Evaluation of Organic Compounds of Nutritional and Environmental Interest

This review would like to show the state of the art regarding the coupling of High-Performance Liquid Chromatography (HPLC) with Electrochemical Detection (ED). Since a universal detector for HPLC is not available, the electrochemical detection methods, thanks to their versatility and specificity, are competitive with respect to the detectors currently used. The papers present in literature on HPLC-ED technique are analyzed and discussed: for example, they regard the development of analytical determinations of resveratrol, rosmarinic acid, aromatic heterocyclic amines and glyphosate in food matrices such as meat, aromatic plants, vegetables, fruit and tomato juices. These papers show that electrochemical sensors used as detectors for HPLC can offer better sensitivity values than other detectors. Furthermore, the use of specific working potentials allows avoid matrix interferences to be avoided by almost exclusively determining the analytes of interest. It should be underlined that HPLC-ED methods have a selectivity that allows for limitation of the sample preparation and clean-up procedures to a minimum, making them quick and easy to apply. In addition, these methods offer advantages such as the possibility of direct analysis, that derivatization is often not necessary, the cost-effectiveness of the instrumentation and the possibility of regenerating the electrodes which allows numerous analyses in succession.

Bisphenol and Phthalate Migration Test from Mexican Meat Packaging Using HPLC-DAD Technique

The objective of this work was to analyze the bisphenols’ and phthalates’ (PAEs) migration from meat packages (of sausages, Winnies, and ham found in Mexican markets) to a water simulant. The determination of these compounds was realized by high performance liquid chromatography (HPLC) and diode array detection (DAD) at a wavelength of 254 nm. The mobile phase utilized was a mixture of acetonitrile:H2O (70 : 30). Elution was performed isocratically at a temperature of 25°C and at a flow rate of 1 mL min−1. The LOQs obtained for BPA, DEP, BADGE, DBP, BisDMA, DHP, DOP, and PA in µg mL−1 were 0.53, 2.09, 0.85, 1.45, 5.81, 1.03, 3.12, and 29.6, respectively. Calibration curves exhibited an adequate determination coefficient for all compounds (R2 >0.999). Excellent accuracy and precision in measurements (% RSD) were achieved. The recovery study showed good applicability of the method (percentage recovery 80% to 106%). The BPA, BADGE, DBP, and DOP concentrations found in samples exceeded the simulant migration limits (SMLs) established by the European Union. The contribution of the current investigation was to provide information related to the presence of bisphenols and PAEs in the package of meat products, highlighting the health risks associated with their exposure.

High-performance liquid chromatographic detection of selected phenolic acidsin wine

The aim of this study was to develop a method for identification and quantification of phenolic acids in different wine samples. The simple reversed-phase HPLC-UV method for simultaneous determination of p-coumaric and ferulic acid was developed. The method was validated and working range, linearity, repeatability, accuracy, limit of quantitation LOQ and limit of detection LOD were determined. The linearity of the method was tested in concentration ranges 0.1-1 mg L-1 and 1-10 mg L-1. The correlation coefficients (r2) were greater than 0.996 and quality coefficients (QC) ≤ 5%. Detection limit for both compounds was 0.01 mg L-1. The method is precise (RSD

Method Validation and Rapid Determination of Monosodium Glutamate in Various Food Products by HPLC-Fluorescence Detection and Method Optimization of HPLC-Evaporative Light Scattering Detection Approach without Derivatization.

In this study, an effective, simple and rapid high-performance liquid chromatography (HPLC) using fluorescence (FLD) method was developed and validated for the determination of monosodium glutamate (MSG) in 57 various food samples. Besides, HPLC-Evaporate Light Scattering Detection (ELSD) method was carried out for determination of MSG without derivatization. MSG analysis was performed by derivatization with dansyl chloride at excitation 328, emission 530nm with fluorescence detector. HPLC-FLD method was carried out by using C18 (150mm, 4.6mm, 2.7μm) column with the mobile phase consisting of (Water: Methanol:Glacial Acetic Acid)/(54:45:1,v/v/v). The column temperature was set at 25°C and the flow rate was set at 0.5mLmin-1 with an injection volume 20μL. The results were linear (R2 = 0.9999) with very low quantification limits. The applied method was optimized and the validated parameters such as LOD, LOQ, accuracy, precision, linearity and robustness were calculated. The obtained results were statistically compared with each other. The validated HPLC-FLD method was successfully applied for the analysis of MSG in all of the food samples. Moreover, HPLC-ELSD method was optimized and successfully demonstrated for detect the MSG without derivatization.

Improved quantification of N-methylcarbamates combining supramolecular post-column derivatization-fluorescence detection-high performance liquid chromatography and partial least squares analysis

A strategy to improve the simultaneous quantification of N-methyl-carbamate pesticides was performed. It takes advantage of the supramolecular interactions between the analytes and hydroxypropyl-β-cyclodextrin (HPCD) in the post-column reactor to increase the high-performance liquid chromatography-fluorescence sensitivity and use the partial least squares algorithm for the data analysis to identify strong overlap signals. The use of HPCD in the derivatization reactor generated a 50% of improvement in the limit of detection of Aminocarb (11.29 ng/ mL), Carbofuran (CF) (19.58 ng/mL) and, Bendiocarb (BC) (0.27 mg/mL). It practically was the same for Carbaryl (2.35 ng/mL), but with a precise identification between CF and BC. The methods developed for these analytes were exactly on the elliptic joint confidence region. The recoveries in domiciliary water indicate the accuracy of the methodologies developed with values between 97% and 103% at the maximum concentration levels allow by international recommendations..

Nutrient content in ora-pro-nóbis (Pereskia aculeata Mill.): unconventional vegetable of the Brazilian Atlantic Forest

Abstract Ora-pro-nobis (Pereskia aculeata Mill.) is an unconventional vegetable found in the Brazilian Atlantic Forest and consumed, mainly by the rural population who lives in this biome. The present study investigated the nutritional value and contribution potential this species to the recommendations of daily nutrient intake for adults. Moisture and ash content were determined by gravimetry after oven drying and muffle incineration, respectively. Proteins were determined by the micro-Kjeldhal method; lipids by gravimetric lipids using soxhlet extractor; Total dietary fiber (TDF) by non-enzymatic gravimetry; Carotenoids and vitamin C by High Performance Liquid Chromatography (HPLC) with Diodes Array Detector; Vitamin E by HPLC and fluorescence detection; and minerals by inductively coupled plasma atomic emission spectrometry (ICP-AES). Ora-pro-nobis presented concentrations of TDF (3.73 g 100 g-1), ash (0.96 g 100 g-1), lipids (1.45 g 100 g-1), protein (1.27 g 100 g-1), carotenoids (3.15 mg 100 g-1), total vitamin E (438.68 µg 100 g-1), Ca (427.08 mg 100 g-1), Mg (88.84 mg 100 g-1), Mn (3.46 mg 100 g-1), Fe (13.89 mg 100 g-1) and K (689.41 mg 100 g-1). The species was considered a source of TDF, a good source of Mg, Cu and K, and an excellent source of vitamin A, Ca, Mn, Fe and Se.

In Vivo Monitoring of Acetylcholine Release from Nerve Endings in Salivary Gland.

Simple SummaryStimulation of the parasympathetic nervous system results in the secretion of saliva. Previous studies have demonstrated acetylcholine content in homogenate obtained from salivary glands. Acetylcholine in homogenate, however, includes that stored in the cells, as well as that released in the interstitial fluid. The activity of the parasympathetic nervous system is mainly determined by the amount of acetylcholine released. We established an in vivo microdialysis method for monitoring the acetylcholine released from nerve endings in the salivary glands in rats. The results of the present study demonstrated that acetylcholine levels in the dialysate reflect acetylcholine levels in the interstitial fluid of the submandibular gland, and that an increase in the acetylcholine level in the dialysate depends predominantly on the release of acetylcholine from the parasympathetic nerve endings.A microdialysis technique was used to monitor acetylcholine levels in the local interstitial fluid in rat submandibular glands, with the aim of determining parasympathetic nerve activity in vivo. The dialysis probe housed a 10 × 0.22 mm semipermeable membrane (molecular weight cutoffs: 50,000 Da). When the probe was perfused at 2 μL/min in vitro, the mean relative recovery of acetylcholine was 41.7% ± 2.5%. The dialysis probes were implanted in the submandibular glands of anesthetized rats and perfusion with Ringer’s solution, at 2 μL/min, was performed. Acetylcholine concentrations in the dialysate were measured by high-performance liquid chromatography and electrochemical detection. The results revealed the following: (1) that mixing Eserine with Ringer’s solution allowed acetylcholine in the salivary glands to be quantified; (2) that acetylcholine concentrations in the dialysate were highly variable and unstable over the first 120 min after probe implantation, but reached a nearly stable level (4.8 ± 2.7 nM) thereafter in the presence of 100 µM of Eserine; and (3) that electrical stimulation of the chorda tympani nerve, or perfusion with high potassium Ringer’s solution, significantly increased acetylcholine concentrations in the dialysate. These results indicate that the present microdialysis technique offers a powerful tool for detecting changes in parasympathetic activity within the salivary glands.

Lipid hydroperoxides in nutrition, health, and diseases.

Research on lipid peroxidation in food degradation, oil and fat nutrition, and age-related diseases has gained significant international attention for the view of improvement of societal health and longevity. In order to promote basic studies on these topics, a chemiluminescence detection-high performance liquid chromatography instrument using a high-sensitivity single photon counter as a detector was developed. This instrument enabled us to selectively detect and quantify lipid hydroperoxides, a primary product of lipid peroxidation reactions, as hydroperoxide groups at the lipid class level. Furthermore, an analytical method using liquid chromatography–tandem mass spectrometry has been established to discriminate the position and stereoisomerization of hydroperoxide groups in lipid hydroperoxides. Using these two methods, the reaction mechanisms of lipid peroxidation in food and in the body have been confirmed.

Selective Extraction and Determination of Citrinin in Rye Samples by a Molecularly Imprinted Polymer (MIP) Using Reversible Addition Fragmentation Chain Transfer Precipitation Polymerization (RAFTPP) with High-Performance Liquid Chromatography (HPLC) Detection

Citrinin (CIT) is a mycotoxin naturally in many foods that causes carcinogenic and mutagenic effects in the human body. A novel method was developed for the selective quantification of citrinin in rye samples. Citrinin-imprinted spheres were fabricated through reversible addition fragmentation chain transfer (RAFT) precipitation polymerization (RAFTPP) in the presence of 2-hydroxymethacrylate (HEMA, functional monomer), ethylene glycol dimethacrylate (EGDMA, cross-linker), citrinin (template), 4-cyano-4-(phenylcarbonothioylthio)pentanoic acid (CTA, RAFT agent), azobisisobutyronitrile (AIBN, initiator), and acetonitrile (ACN, porogen). The imprinted polymers were shown to be spherical with a high surface area and a porous structure. The rebinding properties of citrinin to the imprinted spheres were also examined in detail. The maximum adsorption capacity, equilibration time, and imprinting factor were 38.6 mg g−1, 90 min, and 3.89, respectively. In addition, the citrinin-imprinted spheres were regenerated at least 10 times without change in the adsorption capacity. The citrinin-imprinted particles were used to selectively remove and determine the analyte in rye extract. The calibration relationship was linear between 1 and 100 µg kg−1 with a limit of detection of 0.35 µg kg−1. The method also had high recoveries (98 to 100.0%) and low relative standard deviations (less than 4.1%). Therefore, the imprinted spheres are suitable for the selective determination of citrinin in rye extracts.

Development of ultrasound-assisted centrifugal extraction and online solvent concentration coupled with parallel countercurrent chromatography for the preparation of purified phytochemicals: Application to Lycium ruthenicum

To improve the preparation efficiency of natural products, new techniques for extraction and concentration of natural products have been established. Based on this, an on-line technology to improve the yield and preparation efficiency of natural products have been established. In this study, a novel method to extract natural products from crops and plants, termed ultrasound-assisted centrifugal extraction (UACE), was developed as a supplement to a new online solvent concentration (OSC) technique. These techniques were coupled with parallel countercurrent chromatography (PCCC) and evaluated in the automated preparation of phytochemicals from Lycium ruthenicum. The UACE device comprises an extraction chamber and a solution separation chamber and offers the advantages of higher extraction efficiency, fewer impurities, and conduciveness to sample processing. The OSC device comprises a spray nozzle, concentrating cylinder, and hot-blast air nozzle. The mechanical parameters of the UACE and OSC were optimized, and the operation mode of online UACE combined with OSC and PCCC was described. Raw plant materials were extracted with a two-phase extractant comprising petroleum ether‒ethyl acetate‒ethanol‒water (2:2:1:6, v/v/v/v), and the aqueous and organic phases were then concentrated by OSC. After extraction and online concentration, the concentrate was separated. During PCCC separation, the on-line extraction, and concentration were still conducted. When the first cycle of the UACE/OSC/PCCC was completed, the second cycle was initiated, and so on. As a result, six target compounds with purities exceeding 97.03 % (high performance liquid chromatography detection at 250 nm) were successfully separated using the countercurrent chromatography solvent systems comprising n-heptane‒ethyl acetate‒acetonitrile‒water (20:4:17:1, v/v/v/v) and n-butanol–ethyl acetate–water (55:21:70, v/v/v). Compared with conventional extraction methods, the proposed method offers the advantages of efficiency, automation, high-purity separation of the analytes, and systematic preparation of natural products from crops.

The influence of anesthetics on neurotransmitters in the nervous system of Sepia pharaonis

Anesthesia is a stress mitigation technique widely used during transportation and short-term human manipulation, such as labeling and measurement of body parameters of aquatic animals. This is because anesthetics affect the content of neurotransmitters, exerting various effects on the body. This study determined optimal anesthetic concentration for cuttlefish by measuring the anesthetic and recovery duration of Sepia pharaonis. This was assessed with Nuclear magnetic resonance (NMR) combined with high performance liquid chromatography (HPLC) detection of nervous system metabolites and specific changes in the content of six neurotransmitters. Successful anesthetization of cuttlefish was observed with ethanol concentration (10–30 mL L−1). The cuttlefish recovered after anesthesia, with the longest exposure time being 60 min at a concentration of 10 mL L−1 ethanol. Likewise, the cuttlefish also reached a sedative state at a concentration below 5 mL L−1 ethanol, but with a maximum exposure time of 270 min. We concluded that the action of ethanol attributed to the 10–20% increase of glycine and tyrosine using NMR and HPLC analysis. We postulate the anesthetic role of ethanol in cuttlefish led to increased inhibitory neurotransmitters gamma-Aminobutyric acid, (GABA) and Glycine (Gly) while it reduced the levels of excitatory neurotransmitters acetylcholine (Ach), dopamine (DA) and 5-hydroxytryptamine (5-HT).However, cuttlefish recovery from anesthesia was probably due to rising Ach and Glutamate (Glu) levels.

HPLC Detection and Antioxidant Capacity Determination of Brown, Red and Green Algal Pigments in Seaweed Extracts.

This study was carried out to determine the main pigments in some different selected seaweeds and to reveal their antioxidant potential regarding the ever-increasing demand for utilization of marine pigments in human health and nutrition. The individual amounts of algal pigments were found by reverse phase high-performance liquid chromatography (HPLC) and their total antioxidant capacities (TAC) by two spectrophotometric TAC assays, namely: CUPRAC (CUPric ion Reducing Antioxidant Capacity) and ABTS/TEAC (2,2'-azinobis [3-ethyl benzo thiazoline-6-sulfonate])/(trolox equivalent antioxidant capacity). These two tests gave the same rank order for TAC. The TAC of HPLC-quantified compounds accounted for a relatively much lower percentage of the observed CUPRAC capacities of seaweed extracts, namely ranging from 11 to 68% for brown, from 4 to 41% for red and from 3 to 100% for green species, i.e., some TAC originated from chromatographically unidentified compounds. Fucoxanthin, chlorophyll a, and pheophytin a compounds were major pigments in brown algae. The relative carotenoid contents in red marine algae were generally lower than those of chlorophylls. Overall total quantities were quite low compared with those of brown species. In general, chlorophyll a and chlorophyll b were chiefly present in green algae, but β-carotene, violaxanthin and siphonaxanthin were also detected substantially higher in some species of green algae such as Caulerpa racemosa var. cylindracea and Codium fragile.

Enhancement of functional characteristics of blueberry juice fermented by Lactobacillus plantarum

Lactic acid bacteria with various probiotic functions and excellent fermentation characteristics are widely used in food production, which not only enhance flavor, but also improve functional quality. In this research, Lactobacillus plantarum J26 was selected as the fermented strain in blueberry juice, and the basic indexes, nutritional functional properties, antioxidant capacity and enzyme inhibition were tested to judge the fermentation process influences to blueberry matrix. The results showed that the total amount of phenolic substances increased by 43.42% after fermentation. Four kinds of anthocyanins were found through High Performance Liquid Chromatography (HPLC) detection. Then the scavenging abilities of DPPH, superoxide anion radical and hydroxyl radical were estimated to determine the antioxidant activities of fermented blueberry juice. Moreover, the effect of oxidative damage was also analyzed in the model of Caco-2 cells. Finally, the inhibition of α-glucosidase and α-amylase were both detected in fermented blueberry juice. To sum up, these findings suggested that L. plantarum J26 could be used as fermented strain in the blueberry juice to improve the functional activities.