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Richard J Fitzgerald - One of the best experts on this subject based on the ideXlab platform.
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fractionation and identification of antioxidant peptides from an enzymatically hydrolysed Palmaria palmata protein isolate
Food Research International, 2017Co-Authors: Padraigin A Harnedy, Martina B Okeeffe, Richard J FitzgeraldAbstract:Abstract Proteins derived from the macroalgal species Palmaria palmata have emerged as potential substrates for the generation of bioactive peptides. The aim of this study was to fractionate, identify and characterize antioxidant peptides from a P. palmata protein hydrolysate. The P. palmata protein hydrolysate generated with the food-grade proteolytic enzyme Corolase PP was sequentially fractionated using solid phase extraction and semi-preparative (SP) RP-HPLC. The most active SP-RP-HPLC peptide fraction (SP-RP-HPLC-30-F26) was analysed by ESI-MS/MS. Seventeen novel peptide sequences were identified in this fraction. Of the peptides selected for synthesis, Ser-Asp-Ile-Thr-Arg-Pro-Gly-Gly-Asn-Met, showed the highest oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) activity with values of 152.43 ± 2.73 and 21.23 ± 0.90 nmol TE/μmol peptide, respectively. The results presented herein indicate that P. palmata derived peptides may have potential applications as health enhancing ingredients and as food preservatives due to their antioxidant activity.
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purification and identification of dipeptidyl peptidase dpp iv inhibitory peptides from the macroalga Palmaria palmata
Food Chemistry, 2015Co-Authors: Padraigin A Harnedy, Martina B Okeeffe, Richard J FitzgeraldAbstract:Dipeptidyl peptidase (DPP)-IV inhibitory peptides were purified and identified from an aqueous Palmaria palmata protein extract hydrolysed with Corolase PP. The hydrolysate was fractionated by solid phase extraction (SPE) using a C18 matrix followed by semi-preparative reverse phase-high performance liquid chromatography (SP RP-HPLC). IC50 values of 1.47 ± 0.09, 0.54 ± 0.03 and 0.36 ± 0.03 mg/ml were obtained for the hydrolysate, the 25% – acetonitrile (ACN) SPE fraction and the most active SP RP-HPLC peptide fraction (SP RP-HPLC 25_F28), respectively. Thirteen peptide sequences were identified following UPLC–ESI MS/MS analysis of SP RP-HPLC 25_F28. Three novel DPP-IV inhibitory peptides, Ile-Leu-Ala-Pro, Leu-Leu-Ala-Pro and Met-Ala-Gly-Val-Asp-His-Ile, with IC50 values in the range 43–159 μM were identified. The results indicate that P. palmata derived peptides may have potential as functional food ingredients in the prevention and management of type 2 diabetes.
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the effect of time and origin of harvest on the in vitro biological activity of Palmaria palmata protein hydrolysates
Food Research International, 2014Co-Authors: Padraigin A Harnedy, Anna Solervila, Maeve D Edwards, Richard J FitzgeraldAbstract:Abstract The effect of starting protein composition, and the origin and time of harvesting on the in vitro tyrosinase, dipeptidyl peptidase (DPP) IV and angiotensin converting enzyme (ACE) inhibitory and antioxidant activity of Palmaria palmata protein hydrolysates were investigated. Electrophoretic profiles showed significant differences in aqueous protein extracts obtained from the red macroalga Palmaria palmata harvested at different times of the year. No significant difference was observed in aqueous protein profiles extracted from wild and aquacultured samples of Palmaria palmata. Protein extracts from Palmaria palmata samples harvested from wild plants in April, July and October, and samples cultivated on longlines and harvested in April were hydrolysed with Alcalase 2.4 L and Corolase PP. The hydrolysates, when tested at 10 mg/ml, were shown to inhibit tyrosinase by 37–56%. The oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) values of the hydrolysates ranged from 323–494 and 8.9–19.9 μmol trolox equivalents per gram, respectively. The Palmaria palmata hydrolysates inhibited DPP-IV (IC50: 1.60–4.24 mg/mL) and ACE (IC50: 0.14–0.35 mg/mL) activities. The starting protein composition had a significant effect on the tyrosinase inhibitory activity, while protein composition and hydrolytic enzyme preparation had a significant effect on DPP-IV inhibitory and antioxidant activities. In general, the origin of the samples, wild or cultivated, had no effect on the in vitro biological activity of the protein hydrolysates. The results show that Palmaria palmata hydrolysates may have potential applications as health enhancing ingredients and as food preservatives due to their antioxidant and tyrosinase inhibitory effects.
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in vitro assessment of the cardioprotective anti diabetic and antioxidant potential of Palmaria palmata protein hydrolysates
Journal of Applied Phycology, 2013Co-Authors: Padraigin A Harnedy, Richard J FitzgeraldAbstract:The contribution of protein fraction and proteolytic enzyme preparation to the in vitro cardioprotective, anti-diabetic and antioxidant activity of Palmaria palmata protein hydrolysates was investigated. Aqueous, alkaline and combined aqueous and alkaline P. palmata protein fractions were hydrolysed with the food-grade proteolytic preparations, Alcalase 2.4 L, Flavourzyme 500 L and Corolase PP. The hydrolysates had angiotensin converting enzyme (ACE) and dipeptidyl peptidase (DPP) IV inhibitory activity with IC50 values in the range 0.19–0.78 and 1.65–4.60 mg mL−1, respectively. The oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) values ranged from 45.17 to 467.54 and from 1.06 to 21.59 μmol trolox equivalents/g, respectively. Furthermore, hydrolysates (1 mg mL−1) were show to inhibit renin within the range 0–50 %. In general, Alcalase 2.4 L and Corolase PP hydrolysates of aqueous protein displayed the highest in vitro activity. The results indicate that protein fraction and enzyme preparation used have significant effects on in vitro biofunctional activity of the hydrolysates. This study demonstrates the potential of P. palmata protein hydrolysates as multifunctional functional food ingredients for the prevention/control of hypertension and type II diabetes.
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extraction of protein from the macroalga Palmaria palmata
Lwt - Food Science and Technology, 2013Co-Authors: Padraigin A Harnedy, Richard J FitzgeraldAbstract:Abstract The effect of NaOH and N-acetyl- l -cysteine (NAC) concentration, mass:volume, agitation and extraction temperature on the recovery of alkaline soluble proteins from milled oven-dried Palmaria palmata was studied. The contribution of physical (osmotic shock and shearing) along with enzymatic cell disruption approaches on the extraction of aqueous and alkaline soluble proteins was also assessed. Optimal alkaline soluble protein extraction occurred when using 0.12 mol/l NaOH, 0.1 g/100 ml NAC, a mass to volume ratio of 1:15 (w/v) and when stirring for 1 h at room temperature. The concentration of NaOH and NAC employed were the critical parameters associated with extraction of the alkaline soluble protein. Cell disruption using osmotic shock and high shear treatments resulted in mean alkaline soluble protein recovery of 5.76 and 6.18 g/100 g dry weight, respectively. Prior treatment of macroalgal cells with the food-grade polysaccharidase preparations, Celluclast ® 1.5L and Shearzyme ® 500L, resulted in a mean alkaline soluble protein recovery of 8.39 g/100 g dry weight. However, due to the high enzyme:substrate required, the application of these polysaccharidases may not be feasible for the extraction of intact P. palmata proteins. The results presented herein are relevant to the extraction of intact protein fractions from seaweed sources.
Michael H. Depledge - One of the best experts on this subject based on the ideXlab platform.
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comparison of ultraviolet induced genotoxicity detected by random amplified polymorphic dna with chlorophyll fluorescence and growth in a marine macroalgae Palmaria palmata
Aquatic Toxicology, 2000Co-Authors: Franck A. Atienzar, Britt Cordi, Andrew J. Evenden, Maria E. Donkin, Michael H. DepledgeAbstract:Abstract The random amplified polymorphic DNA (RAPD) technique was used to detect DNA damage in the sublittoral macroalgae Palmaria palmata (Rhodophyta) exposed to both ambient and elevated irradiances of UV-B (280–315 nm). To investigate the potential of this method in ecotoxicological assessments, the qualitative and quantitative modifications in RAPD profiles were compared with changes in a number of physiological and fitness parameters. RAPD detectable modifications in DNA profiles were observed in all UV exposed individuals compared with controls. Changes in chlorophyll fluorescence (Fv/Fm ratio), in vivo pigment absorptance, thallus growth and RAPD profiles, examined simultaneously, provided a sensitive measure of UV-induced toxicity. In conclusion, the application of the RAPD method in conjunction with other suitable physiological and fitness measurements, may prove to be a valuable tool for investigating the specific effects of genotoxic agents upon marine algal populations. Ultimately, this methodology may allow the ecotoxicological examination of the link between molecular alterations and measurable adverse effects at higher levels of biological organisation.
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Comparison of ultraviolet-induced genotoxicity detected by random amplified polymorphic DNA with chlorophyll fluorescence and growth in a marine macroalgae, Palmaria palmata
Aquatic Toxicology, 2000Co-Authors: Franck A. Atienzar, Britt Cordi, Andrew J. Evenden, Awadhesh N. Jha, Maria E. Donkin, Michael H. DepledgeAbstract:The random amplified polymorphic DNA (RAPD) technique was used to detect DNA damage in the sublittoral macroalgae Palmaria palmata (Rhodophyta) exposed to both ambient and elevated irradiances of UV-B (280-315 nm). To investigate the potential of this method in ecotoxicological assessments, the qualitative and quantitative modifications in RAPD profiles were compared with changes in a number of physiological and fitness parameters. RAPD detectable modifications in DNA profiles were observed in all UV exposed individuals compared with controls. Changes in chlorophyll fluorescence (F(v)/F(m) ratio), in vivo pigment absorptance, thallus growth and RAPD profiles, examined simultaneously, provided a sensitive measure of UV-induced toxicity. In conclusion, the application of the RAPD method in conjunction with other suitable physiological and fitness measurements, may prove to be a valuable tool for investigating the specific effects of genotoxic agents upon marine algal populations. Ultimately, this methodology may allow the ecotoxicological examination of the link between molecular alterations and measurable adverse effects at higher levels of biological organisation. © 2000 Elsevier Science B.V.
Britta Grote - One of the best experts on this subject based on the ideXlab platform.
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recent developments in aquaculture of Palmaria palmata linnaeus weber mohr 1805 cultivation and uses
Reviews in Aquaculture, 2019Co-Authors: Britta GroteAbstract:This review summarizes the recent literature on the biology, cultivation techniques and uses of the red seaweed Palmaria palmata ((Linnaeus) Weber & Mohr 1805). The paper covers its distribution, appearance and life cycle, the state of the art cultivation techniques for spore release and seeding, and the culture of meristematic fragments of fronds harvested from natural populations. Furthermore, culture conditions for P. palmata sporelings and gametophytes and set-ups of tank and open sea culture are presented. For tank culture, relatively high irradiance and frequent seawater exchange to supply carbon dioxide and nutrients are the most important parameters. In open sea culture, site selection and system design play an important role. Land-based culture has the advantage that optimum culture conditions can be applied and quality-controlled, whereas nearshore cultivation is less costly and labour intensive. In addition, the bioremediation potential and the use of P. palmata in integrated multitrophic aquaculture (IMTA) are discussed. More research is needed to investigate bioremediation potential of different P. palmata strains. Recent developments in uses of P. palmata as food supplement, source of bioactive compounds, animal feed and compound for biofuels are presented. Finally, the possibilities of cultivation of P. palmata enhance the prospects for the expansion of the cultivation of this seaweed. However, future research is needed regarding balance of culture conditions, costs and biomass in land-based tank culture and in terms of site selection, system design, maintenance and harvest techniques in sea cultivation to establish a commercialization of the aquaculture of this species in Europe.
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Recent developments in aquaculture of Palmaria palmata (Linnaeus) Weber & Mohr 1805): cultivation and uses
Reviews in Aquaculture, 2017Co-Authors: Britta GroteAbstract:This review summarizes the recent literature on the biology, cultivation techniques and uses of the red seaweed Palmaria palmata ((Linnaeus) Weber & Mohr 1805). The paper covers its distribution, appearance and life cycle, the state of the art cultivation techniques for spore release and seeding, and the culture of meristematic fragments of fronds harvested from natural populations. Furthermore, culture conditions for P. palmata sporelings and gametophytes and set-ups of tank and open sea culture are presented. For tank culture, relatively high irradiance and frequent seawater exchange to supply carbon dioxide and nutrients are the most important parameters. In open sea culture, site selection and system design play an important role. Land-based culture has the advantage that optimum culture conditions can be applied and quality-controlled, whereas nearshore cultivation is less costly and labour intensive. In addition, the bioremediation potential and the use of P. palmata in integrated multitrophic aquaculture (IMTA) are discussed. More research is needed to investigate bioremediation potential of different P. palmata strains. Recent developments in uses of P. palmata as food supplement, source of bioactive compounds, animal feed and compound for biofuels are presented. Finally, the possibilities of cultivation of P. palmata enhance the prospects for the expansion of the cultivation of this seaweed. However, future research is needed regarding balance of culture conditions, costs and biomass in land-based tank culture and in terms of site selection, system design, maintenance and harvest techniques in sea cultivation to establish a commercialization of the aquaculture of this species in Europe.
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bioremediation of aquaculture wastewater evaluating the prospects of the red alga Palmaria palmata rhodophyta for nitrogen uptake
Journal of Applied Phycology, 2016Co-Authors: Britta GroteAbstract:The bioremediation capacity of the red macroalga Palmaria palmata was assessed by two experiments. First, uptake rates of P. palmata cultured in four treatments with varying levels and ratios of the N sources ammonium (NH4+) and nitrate (NO3−) (18/15, 0/30, 30/45, 50/65 μM) were measured over a 3-h period to evaluate N source preference. Secondly, P. palmata were cultured in five treatments with varying levels and ratios of ammonium and nitrate (300/12, 0/312, 500/12, 0/512, 250/262 μM) for 3 weeks to evaluate specific growth rates, protein content, and ammonia toxicity. Palmaria palmata had a higher affinity for NH4+ than for NO3− as N source. However, in the single N source trials, NO3− uptake was higher than that of NH4+. The maximum specific growth rate of 11.99 % day−1 was observed in the 0/512 μM ammonium/nitrate treatment after 3 weeks, whereas the minimum specific growth rate of 2.21 % day−1 was observed in the 500/12 μM ammonium/nitrate treatment after 3 weeks. NO3− supported higher growth rates, whereas NH4+ increased tissue N, and therefore protein content. Total protein content of the algal tissue was significantly higher in P. palmata of the NH4+ treatments, reaching up to 20.6 % DW, than of those from the NO3-treatments. Palmaria palmata showed signs of poisoning after 3 weeks in the highest NH4+ treatment. This study indicates that P. palmata is a suitable species for ecological engineering in integrated multitrophic aquaculture systems as it shows a relatively high growth performance, high nutrient uptake rates, and elevated protein content under NH4+ supply.
Joel Fleurence - One of the best experts on this subject based on the ideXlab platform.
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Structural studies of the mix-linked beta-(1-->3)/beta-(1-->4)-D-xylans from the cell wall of Palmaria palmata (Rhodophyta).
International journal of biological macromolecules, 2020Co-Authors: Estelle Deniaud, Joel Fleurence, Bernard Quemener, Marc LahayeAbstract:The structure and organization of Palmaria palmata cell walls, which are largely involved in biological and physiological functions as well as in biotechnological and food applications of this red marine alga, are principally assumed by the interactions and linkages of major mix-linked beta-(1-->3)/beta-(1-->4)-D-xylans. These partly acidic polysaccharides are essentially held in the cell wall by H-bonds. The location of the acid groups and the distribution of 1-->3-linkage were studied following the endo-beta-(1,4)-xylanase hydrolysis of sequentially extracted xylans, and fine analysis of the oligosaccharides produced by anion exchange chromatography, high performance anion exchange chromatography (HPAEC)-PAD, nuclear magnetic resonance (NMR) and electrospray ion trap mass spectrometry (ESI-MS) techniques. The results indicate that the acidity of the xylans was related to potential linkages to sulfated and/or phosphorylated xylogalactoprotein complexes. H-bonding of the mix-linked xylans involved a regular 1,3-linkages distribution idealized in a pentameric repeating structure (one 1,3-linkage and four 1,4-linkages). Furthermore, MS analysis of the xylo-oligosaccharides revealed a substitution of the mix-linked xylans by a non-osidic component of 175 g mol(-1). The presence of this substituent and of the proposed covalent linkage between the mix-linked xylans and charged glycoproteins are discussed with regard to the polysaccharides interactions in P. palmata cell walls.
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optimization of hydrolysis conditions of Palmaria palmata to enhance r phycoerythrin extraction
Bioresource Technology, 2013Co-Authors: Justine Dumay, M. Morançais, Nathalie Clement, Joel FleurenceAbstract:In this study, response surface methodology was applied to optimize R-phycoerythrin extraction from the red seaweed Palmaria palmata, using enzymatic digestion. Several algal treatments prior to digestion were first investigated. The extraction yield and the purity index of R-phycoerythrin, and the recovery of proteins and reducing sugars in the water-soluble fraction were then studied in relation to the hydrolysis time, the temperature and the enzyme/seaweed ratio. Enzymatic digestion appears to be an effective treatment for R-phycoerythrin extraction. Moreover, using the seaweed roughly cut in its wet form gives the most interesting results in terms of extract quality and economic cost. The R-phycoerythrin extraction yield is 62 times greater than without enzyme treatment and 16 times greater than without optimization. Enzymatic optimization enhanced the purity index up to 16 times.
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Optimization of hydrolysis conditions of Palmaria palmata to enhance R-phycoerythrin extraction
Bioresource Technology, 2013Co-Authors: Justine Dumay, M. Morançais, Nathalie Clement, Joel FleurenceAbstract:In this study, response surface methodology was applied to optimize R-phycoerythrin extraction from the red seaweed Palmaria palmata, using enzymatic digestion. Several algal treatments prior to digestion were first investigated. The extraction yield and the purity index of R-phycoerythrin, and the recovery of proteins and reducing sugars in the water-soluble fraction were then studied in relation to the hydrolysis time, the temperature and the enzyme/seaweed ratio.Enzymatic digestion appears to be an effective treatment for R-phycoerythrin extraction. Moreover, using the seaweed roughly cut in its wet form gives the most interesting results in terms of extract quality and economic cost. The R-phycoerythrin extraction yield is 62 times greater than without enzyme treatment and 16 times greater than without optimization. Enzymatic optimization enhanced the purity index up to 16 times. © 2012 Elsevier Ltd.
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simultaneous extraction of proteins and dna by an enzymatic treatment of the cell wall of Palmaria palmata rhodophyta
Journal of Applied Phycology, 2008Co-Authors: Yolaine Joubert, Joel FleurenceAbstract:The extraction of proteins and DNA from seaweed tissue is difficult due to the presence of cell wall anionic polysaccharides that, after cell disruption, remain in the extraction medium as hydrocolloidal compounds. These compounds increase medium viscosity, thus limiting access to and, consequently, quantification of the soluble macromolecules such as proteins or DNA. This study describes a protocol that enables the simultaneous isolation of proteins and DNA from the red seaweed Palmaria palmata. It is based upon a specific form of hydrolysis using a mixture of cellulase and xylanase at different concentrations. This approach was carried out on samples collected during April and July, seasons in which differences in protein content have previously been reported. Our results confirm this report and also show that protein yield depends on the enzyme concentration used. As for DNA, this enzymatic digestion results in a much higher yield compared with the control. However, no seasonal differences are found for DNA and there is no clear link between the increase in DNA yield and the enzyme mixture concentration.
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Evaluation of protein in vitro digestibility of Palmaria palmata and Gracilaria verrucosa
Journal of Applied Phycology, 2005Co-Authors: Olivier Marrion, Joel Fleurence, Jeanlouis Gueant, Annie Schwertz, Lillia Mamelouk, Jamel Ksouri, Christian VillaumeAbstract:Palmaria palmata and Gracilaria verrucosa are edible red seaweeds and potential protein sources for human or animal nutrition, so studies were conducted on their in vitro protein digestibility. After 30 min predigestion by pepsin followed by 6 h digestion into a cell dialysis containing porcine pancreatin, the in vitro protein digestibility of P. palmata and G. verrucosa , expressed in regard to casein digestibility, was 4.9% and 42.1%, respectively. The level of protein digestibility seems to be related to the amount of soluble fibre, which was 45.3% and 30.5%, respectively.
Padraigin A Harnedy - One of the best experts on this subject based on the ideXlab platform.
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fractionation and identification of antioxidant peptides from an enzymatically hydrolysed Palmaria palmata protein isolate
Food Research International, 2017Co-Authors: Padraigin A Harnedy, Martina B Okeeffe, Richard J FitzgeraldAbstract:Abstract Proteins derived from the macroalgal species Palmaria palmata have emerged as potential substrates for the generation of bioactive peptides. The aim of this study was to fractionate, identify and characterize antioxidant peptides from a P. palmata protein hydrolysate. The P. palmata protein hydrolysate generated with the food-grade proteolytic enzyme Corolase PP was sequentially fractionated using solid phase extraction and semi-preparative (SP) RP-HPLC. The most active SP-RP-HPLC peptide fraction (SP-RP-HPLC-30-F26) was analysed by ESI-MS/MS. Seventeen novel peptide sequences were identified in this fraction. Of the peptides selected for synthesis, Ser-Asp-Ile-Thr-Arg-Pro-Gly-Gly-Asn-Met, showed the highest oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) activity with values of 152.43 ± 2.73 and 21.23 ± 0.90 nmol TE/μmol peptide, respectively. The results presented herein indicate that P. palmata derived peptides may have potential applications as health enhancing ingredients and as food preservatives due to their antioxidant activity.
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the effect of consuming Palmaria palmata enriched bread on inflammatory markers antioxidant status lipid profile and thyroid function in a randomised placebo controlled intervention trial in healthy adults
European Journal of Nutrition, 2016Co-Authors: Philip J Allsopp, Padraigin A Harnedy, Anna Solervila, William Crowe, B Bahar, Emma S Brown, Sonja S Taylor, Thomas J Smyth, Pamela J Magee, Chris I R GillAbstract:Purpose Palmaria palmata (P. palmata) is reported to contain anti-inflammatory and antioxidant compounds albeit no study has investigated these effects in humans.
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purification and identification of dipeptidyl peptidase dpp iv inhibitory peptides from the macroalga Palmaria palmata
Food Chemistry, 2015Co-Authors: Padraigin A Harnedy, Martina B Okeeffe, Richard J FitzgeraldAbstract:Dipeptidyl peptidase (DPP)-IV inhibitory peptides were purified and identified from an aqueous Palmaria palmata protein extract hydrolysed with Corolase PP. The hydrolysate was fractionated by solid phase extraction (SPE) using a C18 matrix followed by semi-preparative reverse phase-high performance liquid chromatography (SP RP-HPLC). IC50 values of 1.47 ± 0.09, 0.54 ± 0.03 and 0.36 ± 0.03 mg/ml were obtained for the hydrolysate, the 25% – acetonitrile (ACN) SPE fraction and the most active SP RP-HPLC peptide fraction (SP RP-HPLC 25_F28), respectively. Thirteen peptide sequences were identified following UPLC–ESI MS/MS analysis of SP RP-HPLC 25_F28. Three novel DPP-IV inhibitory peptides, Ile-Leu-Ala-Pro, Leu-Leu-Ala-Pro and Met-Ala-Gly-Val-Asp-His-Ile, with IC50 values in the range 43–159 μM were identified. The results indicate that P. palmata derived peptides may have potential as functional food ingredients in the prevention and management of type 2 diabetes.
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the effect of time and origin of harvest on the in vitro biological activity of Palmaria palmata protein hydrolysates
Food Research International, 2014Co-Authors: Padraigin A Harnedy, Anna Solervila, Maeve D Edwards, Richard J FitzgeraldAbstract:Abstract The effect of starting protein composition, and the origin and time of harvesting on the in vitro tyrosinase, dipeptidyl peptidase (DPP) IV and angiotensin converting enzyme (ACE) inhibitory and antioxidant activity of Palmaria palmata protein hydrolysates were investigated. Electrophoretic profiles showed significant differences in aqueous protein extracts obtained from the red macroalga Palmaria palmata harvested at different times of the year. No significant difference was observed in aqueous protein profiles extracted from wild and aquacultured samples of Palmaria palmata. Protein extracts from Palmaria palmata samples harvested from wild plants in April, July and October, and samples cultivated on longlines and harvested in April were hydrolysed with Alcalase 2.4 L and Corolase PP. The hydrolysates, when tested at 10 mg/ml, were shown to inhibit tyrosinase by 37–56%. The oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) values of the hydrolysates ranged from 323–494 and 8.9–19.9 μmol trolox equivalents per gram, respectively. The Palmaria palmata hydrolysates inhibited DPP-IV (IC50: 1.60–4.24 mg/mL) and ACE (IC50: 0.14–0.35 mg/mL) activities. The starting protein composition had a significant effect on the tyrosinase inhibitory activity, while protein composition and hydrolytic enzyme preparation had a significant effect on DPP-IV inhibitory and antioxidant activities. In general, the origin of the samples, wild or cultivated, had no effect on the in vitro biological activity of the protein hydrolysates. The results show that Palmaria palmata hydrolysates may have potential applications as health enhancing ingredients and as food preservatives due to their antioxidant and tyrosinase inhibitory effects.
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in vitro assessment of the cardioprotective anti diabetic and antioxidant potential of Palmaria palmata protein hydrolysates
Journal of Applied Phycology, 2013Co-Authors: Padraigin A Harnedy, Richard J FitzgeraldAbstract:The contribution of protein fraction and proteolytic enzyme preparation to the in vitro cardioprotective, anti-diabetic and antioxidant activity of Palmaria palmata protein hydrolysates was investigated. Aqueous, alkaline and combined aqueous and alkaline P. palmata protein fractions were hydrolysed with the food-grade proteolytic preparations, Alcalase 2.4 L, Flavourzyme 500 L and Corolase PP. The hydrolysates had angiotensin converting enzyme (ACE) and dipeptidyl peptidase (DPP) IV inhibitory activity with IC50 values in the range 0.19–0.78 and 1.65–4.60 mg mL−1, respectively. The oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) values ranged from 45.17 to 467.54 and from 1.06 to 21.59 μmol trolox equivalents/g, respectively. Furthermore, hydrolysates (1 mg mL−1) were show to inhibit renin within the range 0–50 %. In general, Alcalase 2.4 L and Corolase PP hydrolysates of aqueous protein displayed the highest in vitro activity. The results indicate that protein fraction and enzyme preparation used have significant effects on in vitro biofunctional activity of the hydrolysates. This study demonstrates the potential of P. palmata protein hydrolysates as multifunctional functional food ingredients for the prevention/control of hypertension and type II diabetes.
