Now showing 1 - 10 of 28
  • Publication
    Effect of seasons on the proximate composition of Laminaria hyperborea from Irish Atlantic coast
    This study aimed to analyze the seasonal variation in the proximate composition of Laminaria hyperborea collected in 2016 and 2017, off the west coast of Ireland.
  • Publication
    Biological Properties and Health-Promoting Functions of Laminarin: A Comprehensive Review of Preclinical and Clinical Studies
    Marine algal species comprise of a large portion of polysaccharides which have shown multifunctional properties and health benefits for treating and preventing human diseases. Laminarin, or β-glucan, a storage polysaccharide from brown algae, has been reported to have potential pharmacological properties such as antioxidant, anti-tumor, anti-coagulant, anticancer, immunomodulatory, anti-obesity, anti-diabetic, anti-inflammatory, wound healing, and neuroprotective potential. It has been widely investigated as a functional material in biomedical applications as it is biodegradable, biocompatible, and is low toxic substances. The reported preclinical and clinical studies demonstrate the potential of laminarin as natural alternative agents in biomedical and industrial applications such as nutraceuticals, pharmaceuticals, functional food, drug development/delivery, and cosmeceuticals. This review summarizes the biological activities of laminarin, including mechanisms of action, impacts on human health, and reported health benefits. Additionally, this review also provides an overview of recent advances and identifies gaps and opportunities for further research in this field. It further emphasizes the molecular characteristics and biological activities of laminarin in both preclinical and clinical settings for the prevention of the diseases and as potential therapeutic interventions.
  • Publication
    Exploring ultrasound-assisted extraction to recover high valuable polysaccharides from brown macroalgae and its related antioxidant activities
    This study aimed to optimize the ultrasound-assisted extraction (UAE) parameters of temperature, time and amplitude on the yields of fucose and glucans and their antioxidant activities (FRAP and DPPH) of extracts from Laminaria digitata and to evaluate the application of these optimum UAE parameters in other brown macroalgae (L. hyperborea and Ascophyllum nodosum).
  • Publication
    Effects of extraction method on the prebiotic potential of Ascophylum nodosum extracts
    Seaweed-derived bioactive compounds exhibit various beneficial activities in humans and animals. A factor influencing their concentrations, and subsequent bioactivity, is the extraction method. Our aim was to evaluate the in vitro prebiotic potential of three differently-extracted Ascophylum nodosum samples. The samples were produced using either solid-liquid extraction with water (AN-W), or ethanol (AN-EtOH) as solvent or high pressure-assisted extraction with water as solvent (AN-HPW). All extracts were two-fold diluted from 2 mg/ml to 0.25 mg/ml. Lactobacillus plantarum (LP), L. reuteri (LR) and Bifidobacterium thermophilum (BT) were used at 106 -107 colony-forming unit(CFU)/ml. Each concentration of each extract and controls (0 mg/ml) were incubated for 18 h at 37 °C aerobically or anaerobically (BT). Final bacterial concentrations were determined by spread plating. All experiments were carried out in triplicate with technical replicates. All data were logarithmically transformed and analysed using PROC GLM (SAS 9.4). AN-HPW increased BT (≤0.9 LogCFU/ml, P<0.05) at all concentrations and LR and LP (0.2 LogCFU/ml, P<0.05) at 2 mg/ml and 1mg/ml, respectively. AN-W increased BT (≤0.6 LogCFU/ml, P<0.05) at 1-2mg/ml, but decreased both lactobacilli; LP ≤0.7 LogCFU/ml and LR ≤5.4 LogCFU/ml at all concentrations (P<0.05). AN-EtOH increased LP (≤0.7 LogCFU/ml, P<0.05), but reduced LR (≤5.7 LogCFU/ml, P<0.05) at all concentrations and BT (≤4 LogCFU/ml, P<0.05) at 1-2 mg/ml. In conclusion, the extraction method influenced the prebiotic potential of the A. nodosum extracts in vitro with AN-HPW being the most promising.
  • Publication
    In vitro effects of seaweed extracts on intestinal commensals and pathogens of weaned piglets
    While the inclusion of certain seaweed extracts in weaner piglet diets leads to a beneficial gut microbial profile, the mode of action is not known. The aim of this study was to evaluate the prebiotic and antimicrobial potential of Laminaria digitata and Ascophylum nodosum extracts in vitro. Both extracts were two-fold diluted from 2 mg/ml to 0.25 mg/ml. The following strains were used at 106 -107 colonyforming unit(CFU)/ml concentrations: Lactobacillus plantarum, L. reuteri, Bifidobacterium thermophilum, Enterotoxigenic Escherichia coli O149 and Salmonella enterica ser Typhimurium PT12. Each concentration of each extract and controls (0 mg/ml) were incubated for 18 h at 37 °C aerobically or anaerobically (B. thermophilum). Final bacterial concentrations were determined by spread plating. All experiments were carried out with technical replicates on three independent occasions. All data were logarithmically transformed and analysed using the PROC GLM (SAS 9.4). The L. digitata extract increased B. thermophilum 0.7 LogCFU/ml at 0.25 mg/ml (P<0.05) and ≥1 LogCFU/ml from 0.5-2 mg/ml (P<0.05), with no effect on lactobacilli. The A. nodosum extract increased B. thermophilum up to 0.9 LogCFU/ml at all concentrations tested (P<0.05). Additionally, a 0.2 LogCFU/ml increase of L. reuteri and L. plantarum was observed at 2 mg/ml (P<0.05) and 1mg/ml (P<0.05), respectively. Both extracts displayed no antimicrobial activity against ETEC or S. Typhimurium. In conclusion, both extracts exhibited bifidogenic activity in vitro, with an additional slight increase of Lactobacillus spp. for A. nodosum, indicating a prebiotic potential.
  • Publication
    The influence of duration of feeding dietary vitamin D enriched mushroom powder to finisher pigs on growth performance and meat quality parameters
    Novel feed additives that replace the use of synthetic additives while enhancing pig performance and pork quality are continuously being explored. A complete randomised block design experiment was conducted to examine the effects of the duration of feeding of vitamin D2 enriched mushrooms to finisher pigs and its effect on pig performance and pork quality. Sixty pigs were assigned to one of three dietary treatments for a 69-day feeding period. The dietary treatments were as follows: (T1) basal diet; (T2) basal diet + 1 g/kg of feed vitamin D2 enriched mushroom powder for 48 days prior to slaughter (MPVD-48); and (T3) basal diet + 1 g/kg of feed vitamin D2 enriched mushroom powder for 26 days prior to slaughter (MPVD-26). The mushroom vitamin D content was naturally enriched using synthetic ultraviolet B exposure to obtain a vitamin D2 level of 50 µg/kg of feed. Dietary supplementation of vitamin D2 enriched mushroom powder, irrespective of feeding duration, caused a reduction (P < 0.05) in feed intake, whilst improving (P < 0.05) gain-to-feed ratio. Supplementation of vitamin D2 enriched mushroom powder for 26 days prior to slaughter caused pork lightness (L*) values to remain stable over the 21-day storage time-period compared with all other dietary groups. Supplementation for 26 days also caused a reduction in lipid peroxidation on day 4 of storage compared with supplementation for 48 days. Irrespective of feeding duration, vitamin D2 enriched mushroom powder supplementation improved FRAP (ferric reducing antioxidant power) values of pork compared with the basal. In conclusion, vitamin D2 enriched mushroom supplementation, irrespective of feeding duration, caused a reduction in feed intake but improved feed efficiency. The supplementation of vitamin D2 enriched mushrooms for the shorter duration of 26 days prior to slaughter improved pork quality in relation to colour and antioxidant status.
  • Publication
    Effect of dietary seaweed extracts, galactooligosaccharide and vitamin E supplementation on meat quality parameters in finisher pigs
    Fifty six pigs were assigned to 1 of 4 diets (n = 14) for 35 days pre-slaughter, to assess the effects on bacterial count, lipid peroxidation (LPO) and total antioxidant capacity (TAC) of fresh meat. The treatments were (T1) basal diet (BD), (T2) BD plus seaweed extract (SWE), (T3) BD plus vitamin E (Vit E) and (T4) BD plus galacto-oligosaccharides (GOS). At slaughter longissimus dorsi (LD) steaks were excised and stored in modified atmosphere packs for a 14 day period. The supplemented diets improved the TAC of LD steaks until day 11 of storage while SWE samples exhibited the highest TAC throughout. A reduction (P < 0.05) in the level of LPO was observed in LD steaks from SWE and Vit E supplementation. Compared to basal diet, SWE and GOS exhibited lower bacterial count throughout storage. These results demonstrate the potential for the incorporation of SWE into muscle foods via the diet.
    Scopus© Citations 36  452
  • Publication
    Extraction and yield optimisation of fucose, glucans and associated antioxidant activities from laminaria digitata by applying response surface methodology to high intensity ultrasound-assisted extraction
    The objectives of this study were to employ response surface methodology (RSM) to investigate and optimize the effect of ultrasound-assisted extraction (UAE) variables, temperature, time and amplitude on the yields of polysaccharides (fucose and total glucans) and antioxidant activities (ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity (DPPH)) from Laminaria digitata, and to explore the suitability of applying the optimum UAE conditions for L. digitata to other brown macroalgae (L. hyperborea and Ascophyllum nodosum). The RSM with three-factor, four-level Box-Behnken Design (BBD) was used to study and optimize the extraction variables. A second order polynomial model fitted well to the experimental data with R2 values of 0.79, 0.66, 0.64, 0.73 for fucose, total glucans, FRAP and DPPH, respectively. The UAE parameters studied had a significant influence on the levels of fucose, FRAP and DPPH. The optimised UAE conditions (temperature = 76 ◦C, time = 10 min and amplitude = 100%) achieved yields of fucose (1060.7 ± 70.6 mg/100 g dried seaweed (ds)), total glucans (968.6 ± 13.3 mg/100 g ds), FRAP (8.7 ± 0.5 µM trolox/mg freeze-dried extract (fde)) and DPPH (11.0 ± 0.2%) in L. digitata. Polysaccharide rich extracts were also attained from L. hyperborea and A. nodosum with variable results when utilizing the optimum UAE conditions for L. digitata.
      282Scopus© Citations 70
  • Publication
    Seasonal Variation of the Proximate Composition, Mineral Content, Fatty Acid Profiles and Other Phytochemical Constituents of Selected Brown Macroalgae
    The main objective was to determine the chemical, phytochemical, fatty acid and mineral profiles of three commercially relevant brown macroalgae (Laminaria digitata, Laminaria hyperborea and Ascophyllum nodosum) collected each season for two years off the west coast of Ireland. All the chemical, phytochemical, fatty acid and minerals analysed varied significantly depending on the macroalgal species, season and year of collection. Overall, the protein contents of macroalgae were negatively correlated with carbohydrate content. Protein (2–11%) was at its highest during winter and/or spring, decreasing to a minimum during summer and/or autumn. The three macroalgal species analysed in this study had clearly differentiated fatty acid profiles. The concentration of fatty acids was higher in A. nodosum compared with both Laminaria species. The mineral profile of the three macroalgal species was rich in essential metals, particularly Ca, Mg and P, while the levels of I were approximately 9- to 10-fold higher in both Laminaria spp. compared with A. nodosum. The levels of toxic metals (Cd, Hg and Pb) in all the macroalgal species studied were low in the current study; while the levels of total As were high (49–64 mg/kg DW macroalgae) compared with previous reports.
      313Scopus© Citations 35
  • Publication
    Evaluation of Ultrasound, Microwave, Ultrasound–Microwave, Hydrothermal and High Pressure Assisted Extraction Technologies for the Recovery of Phytochemicals and Antioxidants from Brown Macroalgae
    This study aims to explore novel extraction technologies (ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), ultrasound–microwave-assisted extraction (UMAE), hydrothermal-assisted extraction (HAE) and high-pressure-assisted extraction (HPAE)) and extraction time post-treatment (0 and 24 h) for the recovery of phytochemicals and associated antioxidant properties from Fucus vesiculosus and Pelvetia canaliculata. When using fixed extraction conditions (solvent: 50% ethanol; extraction time: 10 min; algae/solvent ratio: 1/10) for all the novel technologies, UAE generated extracts with the highest phytochemical contents from both macroalgae. The highest yields of compounds extracted from F. vesiculosus using UAE were: total phenolic content (445.0 ± 4.6 mg gallic acid equivalents/g), total phlorotannin content (362.9 ± 3.7 mg phloroglucinol equivalents/g), total flavonoid content (286.3 ± 7.8 mg quercetin equivalents/g) and total tannin content (189.1 ± 4.4 mg catechin equivalents/g). In the case of the antioxidant activities, the highest DPPH activities were achieved by UAE and UMAE from both macroalgae, while no clear pattern was recorded in the case of FRAP activities. The highest DPPH scavenging activities (112.5 ± 0.7 mg trolox equivalents/g) and FRAP activities (284.8 ± 2.2 mg trolox equivalents/g) were achieved from F. vesiculosus. Following the extraction treatment, an additional storage post-extraction (24 h) did not improve the yields of phytochemicals or antioxidant properties of the extracts.
      165Scopus© Citations 27