Evaluation of the antioxidant potential of brown seaweeds extracted by different solvents and characterization of their phenolic compounds by LC-ESI-QTOF-MS/MS.

Seaweeds, serving as valuable natural sources of phenolic compounds (PCs), offer various health benefits like antioxidant, anti-inflammatory properties, and potential anticancer effects. The efficient extraction of PCs from seaweed is essential to harness their further applications. This study compares the effectiveness of different solvents (ethanol, methanol, water, acetone, and ethyl acetate) for extracting PCs from four seaweed species: Ascophyllum sp., Fucus sp., Ecklonia sp., and Sargassum sp. Among them, the ethanol extract of Sargassum sp. had the highest content of total phenolics (25.33 ± 1.45 mg GAE/g) and demonstrated potent scavenging activity against the 2,2-diphenyl-1-picrylhydrazyl radical (33.65 ± 0.03 mg TE/g) and phosphomolybdate reduction (52.98 ± 0.47 mg TE/g). Ecklonia sp. had the highest content of total flavonoids (0.40 ± 0.02 mg QE/g) in its methanol extract, whereas its ethyl acetate extract contained the highest content of total condensed tannins (8.09 ± 0.12 mg CE/g). Fucus sp. demonstrated relatively strong antioxidant activity, with methanolic extracts exhibiting a scavenging ability against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (54.41 ± 0.24 mg TE/g) and water extracts showing ferric-reducing antioxidant power of 36.24 ± 0.06 mg TE/g. Likewise, liquid chromatography-mass spectrometry identified 61 individual PCs, including 17 phenolic acids, 32 flavonoids, and 12 other polyphenols. Ecklonia sp., particularly in the ethanol extract, exhibited the most diverse composition. These findings underscore the importance of selecting appropriate solvents based on the specific seaweed species and desired compounds, further providing valuable guidance in the pharmaceutical, nutraceutical, and cosmetic industries. PRACTICAL APPLICATION: The PCs, which are secondary metabolites present in terrestrial plants and marine organisms, have garnered considerable attention due to their potential health advantages and diverse biological effects. Using various organic/inorganic solvents during the extraction process makes it possible to selectively isolate different types of PCs from seaweed species. The distinct polarity and solubility properties of each solvent enable the extraction of specific compounds, facilitating a comprehensive assessment of the phenolic composition found in the seaweed samples and guiding industrial production.

LC-ESI-QTOF-MS2 Characterization of Phenolic Compounds in Different Lentil (Lens culinaris M.) Samples and Their Antioxidant Capacity.

BACKGROUND: Lentil (Lens culinaris M.) is a legume widely consumed worldwide. It is rich in bioactive compounds, including polyphenolic compounds that contribute to positive health benefits. METHODS: This study aimed to determine the phenolic content and antioxidant activity of black, red, green, and brown whole lentils. Towards this end, the lentils' phenolic compounds were evaluated regarding their total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC), total condensed tannin (TCT), total proanthocyanin content (TPAC), total anthocyanin content (TAC). For the antioxidant activity 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), hydroxyl radical scavenging activity (•OH-RSA), ferrous ion chelating activity (FICA), reducing power assay (RPA) and phosphomolybdate (PMA) assay were accessed. To identify individual phenolic compounds, liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS2) was used. RESULTS: The results showed that green lentils exhibited the highest TPC (0.96 mg gallic acid equivalents (GAE)/g) whereas red lentils presented the highest TFC (0.06 mg quercetin equivalents (QE)/g). Black lentils were noted with the highest TCT (0.03 mg catechin equivalents (CE)/g), TPAC (0.009 mg cyanidin chloride equivalents (CCE)/g), and TAC (3.32 mg/100 g) contents. While the greatest TTC (2.05 mg tannic acid equivalents (TAE)/g) was observed in the brown lentil. Regarding the total antioxidant capacity, red lentils (4.01 mg ascorbic acid equivalents (AAE)/g) presented the greatest activity, whereas the lowest was found in the brown samples (2.31 mg AAE/g). The LC-ESI-QTOF-MS2 tentatively identified a total of 22 phenolic compounds, containing 6 phenolic acids, 13 flavonoids, 2 lignans, and 1 other polyphenol. The relationships among phenolic compounds by Venn Diagram showed a high number of overlapping compounds in brown and red lentils (6.7%), and a low number of overlapping compounds between the green, brown, and black lentils (2.6%). Flavonoids were the most abundant phenolic compound within the studied whole lentils, with the brown lentils being the richest in phenolic compounds, especially flavonoids. CONCLUSIONS: This study emphasized a comprehensive understanding of the antioxidant potential of lentils and disclosed the phenolic distribution across various lentil samples. This may increase interest in the development of functional food products, nutraceutical ingredients, and pharmaceutical applications with lentils.

Bioaccessibility and bioactivities of phenolic compounds from roasted coffee beans during in vitro digestion and colonic fermentation.

Bioaccessibility and bioactivity of phenolic compounds in coffee beans relate to roasting and digestion process. This study aimed to estimate phenolic content, antioxidant potential, bioaccessibility, and changes in short chain fatty acids (SCFAs) production during in vitro digestion and colonic fermentation of commercial roasted (light, medium and dark) coffee beans. There was no significant difference found among all three different roasting levels. TPC and DPPH were enhanced 15 mg GAE/g and 60 mg TE/g during gastrointestinal digestion, respectively. For colonic fermentation, the highest TPC and FRAP of all coffee beans was found at 2 and 4 h, respectively. The gastric bioaccessibility of most of the phenolic compounds were relatively higher due to thermal phenolic degradation. Total SCFAs production was only up to 0.02 mM because of thermal polysaccharide decomposition. Light roasted beans exhibited relatively higher phenolic bioaccessibility, antioxidant activities and SCFAs production, which would be more beneficial to gut health.

Multiproduct biorefinery from marine thraustochytrids towards a circular bioeconomy.

Microalgal biotechnology research continues to expand due to largely unexplored marine environments and growing consumer interest in healthy products. Thraustochytrids, which are marine oleaginous protists, are known for their production of bioactives with significant applications in nutraceuticals, pharmaceuticals, and aquaculture. A wide range of high-value biochemicals, such as nutritional supplements (omega-3 fatty acids), squalene, exopolysaccharides (EPSs), enzymes, aquaculture feed, and biodiesel and pigment compounds, have been investigated. We discuss thraustochytrids as potential feedstocks to produce various bioactive compounds and advocate developing a biorefinery to offset production costs. We anticipate that future advances in cell manufacturing, lipidomic analysis, and nanotechnology-guided lipid extraction would facilitate large-scale cost-competitive production through these microbes.

Unveiling the dermatological potential of marine fungal species components: Antioxidant and inhibitory capacities over tyrosinase.

Marine fungi are a rich source of biologically active molecules, but a poorly explored bioresource for cosmeceutical products. This study evaluates the phytochemistry, antioxidant, and antityrosinase effects of the organic extracts of marine fungi isolated from various marine environments in India. Out of 35 screened fungal strains, methanol extracts of strains P2, Talaromyces stipitatus, and D4, Aspergillus terreus exhibited antityrosinase activity of 45% and 43%, respectively, at the lowest concentration of 0.5 mg/mL. The highest free radicals scavenging activity of 94% and 97% was observed at 500 mg/mL, respectively, of the same fungal extracts. The total phenolic content ranged from 8.20 to 20.30 mg/g of the dry weight of extract, expressed as gallic acid equivalent. GC-MS analysis of T. stipitatus and A. terreus extract identified seven and 10 major compounds, respectively. Some of the major compounds included azetidine, (3E)-3-[(3,5-dimethoxybenzoyl)hydrazono]-N-isobutyl butanamide, aziridine, and 3-methylcyclopentanone, 1,1-dimethylcyclohexane, cyclopentane carboxylic acid, N-allyl-4,5,6,7-tetrahydro-2-benzothiophene-1-carboxamide, cyclo(l-Pro-l-Val), and 3-phenylpropionitrile. In conclusion, this study showed abundant fungal resources in Indian marine environments. A correlation between total phenolic contents of the extracts confirmed that phenolic compounds play an important role in antioxidant as well as antityrosinase activity of the marine fungal extracts and can be viewed as new potential antityrosinase and antioxidant resources.

LC-ESI-QTOF-MS/MS Characterization of Seaweed Phenolics and Their Antioxidant Potential.

Seaweed is an important food widely consumed in Asian countries. Seaweed has a diverse array of bioactive compounds, including dietary fiber, carbohydrate, protein, fatty acid, minerals and polyphenols, which contribute to the health benefits and commercial value of seaweed. Nevertheless, detailed information on polyphenol content in seaweeds is still limited. Therefore, the present work aimed to investigate the phenolic compounds present in eight seaweeds [Chlorophyta (green), Ulva sp., Caulerpa sp. and Codium sp.; Rhodophyta (red), Dasya sp., Grateloupia sp. and Centroceras sp.; Ochrophyta (brown), Ecklonia sp., Sargassum sp.], using liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS). The total phenolic content (TPC), total flavonoid content (TFC) and total tannin content (TTC) were determined. The antioxidant potential of seaweed was assessed using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, a 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radical scavenging assay and a ferric reducing antioxidant power (FRAP) assay. Brown seaweed species showed the highest total polyphenol content, which correlated with the highest antioxidant potential. The LC-ESI-QTOF-MS/MS tentatively identified a total of 54 phenolic compounds present in the eight seaweeds. The largest number of phenolic compounds were present in Centroceras sp. followed by Ecklonia sp. and Caulerpa sp. Using high-performance liquid chromatography-photodiode array (HPLC-PDA) quantification, the most abundant phenolic compound was p-hydroxybenzoic acid, present in Ulva sp. at 846.083 ± 0.02 µg/g fresh weight. The results obtained indicate the importance of seaweed as a promising source of polyphenols with antioxidant properties, consistent with the health potential of seaweed in food, pharmaceutical and nutraceutical applications.

Lipase-catalysed synthesis of palm oil-omega-3 structured lipids.

In this work, Candida antarctica lipase A was applied to selectively remove saturated fatty acids from palm oil to prepare palm oil acylglycerol concentrate (POAC), where palmitic acid decreased from 40.0 to 28.7% and oleic acid increased from 40.0 to 50.5% after 3 h of hydrolysis. Lipozyme RMIM from Rhizomucor miehei was then used to incorporate either alpha linolenic acid (ALA) or eicosapentaenoic acid (EPA) into the resulting POAC. Optimum omega-3 incorporation was achieved when POAC to omega-3 ratio was 6 : 3, reaction temperature was 40 °C and reaction time was 18 h. Under these conditions, the ALA content in the separated ALA incorporated structured lipid (POAC-ALA) was 27.1%, and the EPA content in the EPA incorporated structured lipids (POAC-EPA) was 30.9%. The formed structured lipids had lower levels of saturated fatty acids, and significantly lower melting points, in both cases below 8 °C. The enzymatic process developed produces new structured lipids, with lower saturated fat and higher omega-3, with potential as a healthy palm oil derived lipid ingredient.

Enzyme-free fluorescent detection of microcystin-LR using hairpin DNA-templated copper nanoclusters as signal indicator.

Microcystin-LR (MC-LR) is a potent hepatotoxin that is often associated with blooms of cyanobacteria. The analysis of trace MC-LR plays important role in environmental and health fields. Herein, we developed a low-cost and enzyme-free detection method of MC-LR by using hairpin DNA-templated copper nanoclusters (hpDNA-CuNCs) as fluorescent probe. The hpDNA-template was designed and fabricated by a MC-LR aptamer loop and a double strand stem, which can specifically recognize target MC-LR with strong affinity. The AT-rich and complementary double strand stem serves as a template for the formation of CuNCs. The formed fluorescent sensing probe of hpDNA-CuNCs exhibits maximum emission wavelength at 575 nm. Upon the addition of target MC-LR into the hpDNA-CuNCs, we observed fluorescence was quenched considerably due to the high affinity between MC-LR and hpDNA aptamer strand loop, which indicated a conformational change of hairpin probe from the stem-loop DNA structure to single-stranded DNA. Then, the change of fluorescence intensity can be used to monitor the concentration of MC-LR from 0.005 to 1200 µg L-1 with a detection limit of 0.003 ng L-1. Compared with the previous reports, this method does not require complex DNA sequence design, fluorescence dye label and sophisticated experimental techniques. Moreover, the target MC-LR in real water samples has been detected.

Investigation of oil distribution in spray-dried chia seed oil microcapsules using synchrotron-FTIR microspectroscopy.

In this study, chia seed oil (CSO) microcapsules were produced using three types of shell materials, including chia seed protein (CPI), chia seed gum (CSG) and CPI-CSG complex coacervates. Synchrotron-Fourier transform infrared (S-FTIR) microspectroscopy was used to investigate the effect of shell materials on the distribution of CSO both on the surface and in the interior of the solid microcapsules. S-FTIR measurements were carried out in macroscopic attenuated total reflection (macro ATR) and transmission modes, to determine the surface lipid and the encapsulated lipid fractions, respectively. The amounts of lipid and protein distributed on the surface and in the interior of the microcapsules were compared based on the average spectra extracted from S-FTIR chemical images obtained from each type of the microcapsules. The unsaturated fatty acids (UFAs) to total oil ratios in all the three types of the microcapsules were closely similar to the original non-processed CSO, suggesting an effective encapsulation and thereby shielding protection of UFAs from oxidative damage during microencapsulation process. The type of the shell materials was found to affect the distribution of CSO on the surface and within the microcapsules. The complex coacervation based microcapsules had a significantly lower oil content (∼2% w/w) on the surface compared to those observed for the other two types of microcapsules (>5%, w/w).

Gypenosides as natural emulsifiers for oil-in-water nanoemulsions loaded with astaxanthin: Insights of formulation, stability and release properties.

The formulation, physicochemical stability and bioaccessibility of astaxanthin (AST) loaded oil-in-water nanoemulsions fabricated using gypenosides (GPs) as natural emulsifiers was investigated and compared with a synthetic emulsifier (Tween 20) that is commonly applied in food industry. GPs were capable of producing nanoemulsions with a small volume mean diameter (d4,3 = 125 ±â€¯2 nm), which was similar to those prepared using Tween 20 (d4,3 = 145 ±â€¯6 nm) under the same high-pressure homogenization conditions. GPs-stabilized nanoemulsions were stable against droplet growth over a range of pH (6-8) and thermal treatments (60-120 °C). Conversely, instability occurred under acidic (pH 3-5) and high ionic strength (25-100 mM CaCl2) conditions. In comparison with Tween 20, GPs were more effective at inhibiting AST from degradation during 30 days of storage at both 5 and 25 °C. However, GPs led to lower lipid digestion and AST bioaccessibility from nanoemulsions than did Tween 20.

Formulation and characterization of astaxanthin-enriched nanoemulsions stabilized using ginseng saponins as natural emulsifiers.

In this study ginseng saponins (GS) were used as natural emulsifiers to formulate and stabilize O/W nanoemulsions loaded with astaxanthin (AST). GS were found to be highly effective at reducing the interfacial tension at the soybean oil-water interfaces, and were capable of producing nano-scaled droplets (d4,3 ≈ 125 nm) using a high-pressure homogenizer. The droplet size of the nanoemulsions decreased with increasing emulsifier concentration and homogenization pressure. The nanoemulsions were stable without droplet coalescence against thermal treatment (30-90 °C, 30 min), and over a narrow range of pH values (7-9). GS-coated droplets were unstable in acidic conditions (pH 3-6) and in the presence of salt (>25 mM NaCl). The formulated nanoemulsions showed slight change in d4,3 during 15 days of storage at 5, 25 and 40 °C. However, the chemical stability strongly depended on the storage temperature, with the lowest level of AST retained in nanoemulsions stored at higher temperature.

In-vitro evaluation of marine derived fungi against Cutibacterium acnes.

Cutibacterium acnes (or Propionibacterium acnes) is the main target for the prevention and medical treatment of acne vulgaris. The aim of this study was to evaluate the in vitro anti-C. acnes and anti-S. epidermidis properties of some marine fungi isolated from different Indian marine environments. Seventy fungal isolates were obtained from samples collected from the west coasts and Andaman Island, India. Methanol extracts of 35 isolates were screened for their antibacterial properties and 5 out of the 35 isolates displayed significant inhibition as compared with tetracycline. DNA was successfully extracted from these five fungal isolates and phylogenetic analysis was performed. The methanol extracts possessed antibacterial activity against C. acnes and S. epidermidis with MIC values ranged from 0.8 mg/mL to 1 mg/mL. SEM analysis revealed that the extract induces deleterious morphological changes in the bacterial cell membrane. This study has identified some fungi extracts with significant antibacterial activity. The extracts may have potential for development as an antibacterial agent in the treatment of acne vulgaris.

Formulation and characterization of O/W nanoemulsions encapsulating high concentration of astaxanthin.

This study evaluates the effect of modified lecithin (ML) and sodium caseinate (SC) on the formulation, stability and bioaccessibility of astaxanthin (AXT) loaded oil-in-water (O/W) nanoemulsions. These nanoemulsions were formulated using high-pressure homogenization in four passes at 100MPa. The volume mean diameter (d4,3) of nanoemulsions produced by ML and SC were 163±5 and 144±12 nm, respectively. The physiochemical stability of nanoemulsions was recorded at 25°C. The nanoemulsions prepared by ML were stable for 30 minutes against a wide range of pH and heating temperatures (60-120 °C). However, ML-stabilized nanoemulsions showed droplet growth when treated at high NaCl concentrations. In comparison, droplet growth was observed in SC-stabilized nanoemulsions at pH4 and at high temperature treatment. However, SC-stabilized nanoemulsions were stable at high NaCl concentration (500 mM). The SC-stabilized nanoemulsions showed good physical and chemical stability (>70%) after 30 days of storage. The bioaccessibility of AXT in nanoemulsions was significantly higher in ML (33%) than in SC-stabilized nanoemulsions (6%), indicating a strong influence of emulsifier on bioaccessibility. These findings provide valuable information in designing nutritional products such as aqueous based AXT fortified beverages.

Microencapsulation of chia seed oil using chia seed protein isolate-chia seed gum complex coacervates.

Chia seed oil (CSO) microcapsules were produced by using chia seed protein isolate (CPI)-chia seed gum (CSG) complex coacervates aiming to enhance the oxidative stability of CSO. The effect of wall material composition, core-to-wall ratio and method of drying on the microencapsulation efficiency (MEE) and oxidative stability (OS) was studied The microcapsules produced using CPI-CSG complex coacervates as wall material had higher MEE at equivalent payload, lower surface oil and higher OS compared to the microcapsules produced by using CSG and CPI individually. CSO microcapsules produced by using CSG as wall material had lowest MEE (67.3%) and oxidative stability index (OSI=6.6h), whereas CPI-CSG complex coacervate microcapsules had the highest MEE (93.9%) and OSI (12.3h). The MEE and OSI of microcapsules produced by using CPI as wall materials were in between those produced by using CSG and CPI-CSG complex coacervates as wall materials. The CSO microcapsules produced by using CPI-CSG complex coacervate as shell matrix at core-to-wall ratio of 1:2 had 6 times longer storage life compared to that of unencapsulated CSO. The peroxide value of CSO microcapsule produced using CPI-CSG complex coacervate as wall material was <10meq O2/kg oil during 30 days of storage.

A quick colorimetric method for total lipid quantification in microalgae.

Discovering microalgae with high lipid productivity are among the key milestones for achieving sustainable biodiesel production. Current methods of lipid quantification are time intensive and costly. A rapid colorimetric method based on sulfo-phospho-vanillin (SPV) reaction was developed for the quantification of microbial lipids to facilitate screening for lipid producing microalgae. This method was successfully tested on marine thraustochytrid strains and vegetable oils. The colorimetric method results correlated well with gravimetric method estimates. The new method was less time consuming than gravimetric analysis and is quantitative for lipid determination, even in the presence of carbohydrates, proteins and glycerol.

Selective Enrichment of Omega-3 Fatty Acids in Oils by Phospholipase A1.

Omega fatty acids are recognized as key nutrients for healthier ageing. Lipases are used to release ω-3 fatty acids from oils for preparing enriched ω-3 fatty acid supplements. However, use of lipases in enrichment of ω-3 fatty acids is limited due to their insufficient specificity for ω-3 fatty acids. In this study use of phospholipase A1 (PLA1), which possesses both sn-1 specific activity on phospholipids and lipase activity, was explored for hydrolysis of ω-3 fatty acids from anchovy oil. Substrate specificity of PLA1 from Thermomyces lenuginosus was initially tested with synthetic p-nitrophenyl esters along with a lipase from Bacillus subtilis (BSL), as a lipase control. Gas chromatographic characterization of the hydrolysate obtained upon treatment of anchovy oil with these enzymes indicated a selective retention of ω-3 fatty acids in the triglyceride fraction by PLA1 and not by BSL. 13C NMR spectroscopy based position analysis of fatty acids in enzyme treated and untreated samples indicated that PLA1 preferably retained ω-3 fatty acids in oil, while saturated fatty acids were hydrolysed irrespective of their position. Hydrolysis of structured triglyceride,1,3-dioleoyl-2-palmitoylglycerol, suggested that both the enzymes hydrolyse the fatty acids at both the positions. The observed discrimination against ω-3 fatty acids by PLA1 appears to be due to its fatty acid selectivity rather than positional specificity. These studies suggest that PLA1 could be used as a potential enzyme for selective concentrationof ω-3 fatty acids.

Exploring the Effects of Omega-3 and Omega-6 Fatty Acids on Allergy Using a HEK-Blue Cell Line.

BACKGROUND: Allergic reactions can result in life-threatening situations resulting in high economic costs and morbidity. Therefore, more effective reagents are needed for allergy treatment. A causal relationship has been suggested to exist between the intake of omega-3/6 fatty acids, such as docosahexanoic acid (DHA), eicosapentanoic acid (EPA), docosapentanoic acid (DPA) and arachidonic acid (AA), and atopic individuals suffering from allergies. In allergic cascades, the hallmark cytokine IL-4 bind to IL-4 receptor (IL-4R) and IL-13 binds to IL-13 receptor (IL-13R), this activates the STAT6 phosphorylation pathway leading to gene activation of allergen-specific IgE antibody production by B cells. The overall aim of this study was to characterize omega-3/6 fatty acids and their effects on STAT6 signaling pathway that results in IgE production in allergic individuals. METHODS: The fatty acids were tested in vitro with a HEK-Blue IL-4/IL-13 reporter cell line model, transfected with a reporter gene that produces an enzyme, secreted embryonic alkaline phosphatase (SEAP). SEAP acts as a substitute to IgE when cells are stimulated with bioactive cytokines IL-4 and/or IL-13. RESULTS: We have successfully used DHA, EPA and DPA in our studies that demonstrated a decrease in SEAP secretion, as opposed to an increase in SEAP secretion with AA treatment. A statistical Student's t-test revealed the significance of the results, confirming our initial hypothesis. CONCLUSION: We have successfully identified and characterised DHA, EPA, DPA and AA in our allergy model. While AA was a potent stimulator, DHA, EPA and DPA were potential inhibitors of IL-4R/IL-13R signalling, which regulates the STAT6 induced pathway in allergic cascades. Such findings are significant in the future design of dietary therapeutics for the treatment of allergies.

Synthesis and characterization of surface-enhanced Raman-scattered gold nanoparticles.

In this paper, we report a simple, rapid, and robust method to synthesize surface-enhanced Raman-scattered gold nanoparticles (GNPs) based on green chemistry. Vitis vinifera L. extract was used to synthesize noncytotoxic Raman-active GNPs. These GNPs were characterized by ultraviolet-visible spectroscopy, dynamic light-scattering, Fourier-transform infrared (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy. The characteristic surface plasmon-resonance band at ~ 528 nm is indicative of spherical particles, and this was confirmed by TEM. The N-H and C-O stretches in FTIR spectroscopy indicated the presence of protein molecules. The predominant XRD plane at (111) and (200) indicated the crystalline nature and purity of GNPs. GNPs were stable in the buffers used for biological studies, and exhibited no cytotoxicity in noncancerous MIO-M1 (Müller glial) and MDA-MB-453 (breast cancer) cell lines. The GNPs exhibited Raman spectral peaks at 570, 788, and 1,102 cm(-1). These new GNPs have potential applications in cancer diagnosis, therapy, and ultrasensitive biomarker detection.

Pollen baiting facilitates the isolation of marine thraustochytrids with potential in omega-3 and biodiesel production.

Marine heterotrophic microbes are capable of accumulating large amounts of lipids, omega-3 fatty acids, carotenoids, and have potential for biodiesel production. Pollen baiting using Pinus radiata pollen grain along with direct plating techniques were used in this study as techniques for the isolation of oil-producing marine thraustochytrid species from Queenscliff, Victoria, Australia. Thirteen isolates were obtained using either direct plating or using pine pollen, with pine pollen acting as a specific substrate for the surface attachment of thraustochytrids. The isolates obtained from the pollen baiting technique showed a wide range of docosahexaenoic acid (DHA) accumulation, from 11 to 41 % of total fatty acid content (TFA). Direct plating isolates showed a moderate range of DHA accumulation, from 19 to 25 % of TFA. Seven isolates were identified on the basis of 18S rRNA sequencing technique as Thraustochytrium species, Schizochytrium species, and Ulkenia species. Although both methods appear to result in the isolation of similar strains, pollen baiting proved to be a simpler method for the isolation of these relatively slow-growing organisms.

Quantitative determination of fatty acid compositions in micro-encapsulated fish-oil supplements using Fourier transform infrared (FTIR) spectroscopy.

The research describes a rapid method for the determination of fatty acid (FA) contents in a micro-encapsulated fish-oil (µEFO) supplement by using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic technique and partial least square regression (PLSR) analysis. Using the ATR-FTIR technique, the µEFO powder samples can be directly analysed without any pre-treatment required, and our developed PLSR strategic approach based on the acquired spectral data led to production of a good linear calibration with R(2)=0.99. In addition, the subsequent predictions acquired from an independent validation set for the target FA compositions (i.e., total oil, total omega-3 fatty acids, EPA and DHA) were highly accurate when compared to the actual values obtained from standard GC-based technique, with plots between predicted versus actual values resulting in excellent linear fitting (R(2)≥0.96) in all cases. The study therefore demonstrated not only the substantial advantage of the ATR-FTIR technique in terms of rapidness and cost effectiveness, but also its potential application as a rapid, potentially automated, online monitoring technique for the routine analysis of FA composition in industrial processes when used together with the multivariate data analysis modelling.