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Rajauria, Gaurav
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Rajauria, Gaurav
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Rajauria, Gaurav
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Now showing 1 - 10 of 27
- PublicationUltrasonic extraction(Teagasc, 2018-08-08)
; ; ; Found in seaweed, fucoidans have many beneficial properties, but extracting them from the plant has proved difficult. UCD and TEAGASC researchers looked at one promising technology.66 - PublicationEffect of seasons on the proximate composition of Laminaria hyperborea from Irish Atlantic coast(2018-10-27)
; ; ; ; 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.27 - PublicationEffect of dietary seaweed extracts, galactooligosaccharide and vitamin E supplementation on meat quality parameters in finisher pigsFifty 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.
354Scopus© Citations 30 - PublicationIn vitro effects of seaweed extracts on intestinal commensals and pathogens of weaned piglets(Microbiology Society, 2018-06-21)
; ; ; ; ; 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.38 - PublicationThe effect of 25‐hydroxyvitamin D3 and phytase inclusion on pig performance, bone parameters and pork quality in finisher pigs(Wiley, 2018-10)
; ; ; ; ; ; The objective of this study was to investigate the effects of supplementing both phytase and 25-hydroxyvitamin D3 (25-OH-D₃) on pig performance, nutrient digestibility, carcass characteristics, bone parameters and pork quality in finisher pigs. The experimental design was a 2 × 2 factorial comprising of four dietary treatments. One hundred and twenty pigs (60 male, 60 female) were blocked according to live weight and sex and allocated to the following dietary treatments: low P (4.81 g/kg) diet (basal) (T1); low P diet + phytase (T2); low P diet + 25-OH-D₃ (T3) and low P diet + phytase + 25-OH-D₃ (T4). Pigs supplemented with phytase had a lower average daily feed intake (ADFI) (2.45 kg vs. 2.59 kg; p < 0.05) and lower feed conversion ratio (FCR) (2.74 kg/kg vs. 2.85 kg/kg; p < 0.05) compared to pigs offered the nonphytase diets. Pigs offered phytase diets had a higher (p < 0.05) coefficient of apparent total tract digestibility (CATTD) of ash, phosphorous (P) and calcium (Ca) compared with pigs offered the nonphytase supplemented diets. Pigs offered the 25-OH-D3 diets had a higher CATTD of N and ash. Pigs offered the phytase diets had increased (p < 0.05) bone DM, ash, Ca, P and density compared to the nonphytase diets. There was a significant interaction (p < 0.05) between phytase and 25-OH-D3 on cook loss. Pigs offered 25-OH-D3 had increased cook loss over the basal diet; however, there was no effect on cook loss when phytase and 25-OH-D3 were offered in combination compared to the phytase only diet. Pigs offered 25-OH-D3 exhibited higher (p < 0.05) Warner Bratzler shear force values and lower (p < 0.05) pork lightness (L*) surface colorimeter values. In conclusion, there was no benefit to offering a combination of phytase and 25-OH-D3 on pig performance, bone parameters or pork quality.384Scopus© Citations 14 - PublicationThe potential of cholecalciferol and 25-hydroxyvitamin D3 enriched diets in laying hens, to improve egg vitamin D content and antioxidant availability(Elsevier, 2017-12)
; ; ; ; ; Sixty Hy-line brown hens were randomly assigned to four barns (n = 4) to investigate the effects of cholecalciferol (vitamin D₃) versus 25-hydroxyvitamin D3 (25-OH-D₃) enriched diets on egg vitamin D concentration, antioxidant activity and egg quality parameters. Experimental design was a 4 × 4 Latin square consisting of 4 experimental treatments and 4 experimental periods. The treatments were (1) 1500 IU of vitamin D₃ (2) 3000 IU of vitamin D₃ (3) 1500 IU of vitamin D₃ and 37.5 μg of 25-OH-D₃ (4) 75 μg of 25-OH-D₃ per kg of feed. Hens offered 75 μg of 25-OH-D₃ had a higher (P < 0.05) total vitamin D egg yolk content (5.06 μg/egg), and antioxidant activity compared to other dietary treatments. The results demonstrates that the enrichment of hen diets with 25-OH-D₃ may be a useful approach and may contribute between 25 and 33% towards total vitamin D daily requirements while also improving antioxidant status of eggs. Industrial relevance: Vitamin D deficiency is now regarded as a major issue in northern Europe and has been described as a pandemic. A growing interest in vitamin D food fortification in northern Europe to satisfy the current dietary intake recommendations has been observed. The use of a bio-addition approach for increasing vitamin D intake through biofortification of livestock feeds attracts attention. Enrichment of the hen's diet with vitamin D may also supply additional benefits of increasing antioxidant activity. This increase in antioxidant activity may have the ability to increase food quality and extend the shelf life. This study explores the effect of vitamin D enriched diets fed to laying hens on vitamin D egg yolk content and antioxidant activity in the egg. These enriched diets could demonstrate that enrichment of hen diets with 25-hyroxvitamin D₃ may be a useful approach for tackling low vitamin D intakes and improving antioxidant capacity of eggs.294Scopus© Citations 14 - PublicationOptimisation of Ultrasound Frequency, Extraction Time and Solvent for the Recovery of Polyphenols, Phlorotannins and Associated Antioxidant Activity from Brown Seaweeds(MDPI, 2020-05-11)
; ; ; ; ; ; ; This study investigates ultrasound assisted extraction (UAE) process parameters (time, frequency and solvent) to obtain high yields of phlorotannins, flavonoids, total phenolics and associated antioxidant activities from 11 brown seaweed species. Optimised UAE conditions (35 kHz, 30 min and 50% ethanol) significantly improved the extraction yield from 1.5-fold to 2.2-fold in all seaweeds investigated compared to solvent extraction. Using ultrasound, the highest recovery of total phenolics (TPC: 572.3 ± 3.2 mg gallic acid equivalent/g), total phlorotannins (TPhC: 476.3 ± 2.2 mg phloroglucinol equivalent/g) and total flavonoids (TFC: 281.0 ± 1.7 mg quercetin equivalent/g) was obtained from Fucus vesiculosus seaweed. While the lowest recovery of TPC (72.6 ± 2.9 mg GAE/g), TPhC (50.3 ± 2.0 mg PGE/g) and TFC (15.2 ± 3.3 mg QE/g) was obtained from Laminaria digitata seaweed. However, extracts from Fucus serratus obtained by UAE exhibited the strongest 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity (29.1 ± 0.25 mg trolox equivalent/g) and ferric reducing antioxidant power (FRAP) value (63.9 ± 0.74 mg trolox equivalent/g). UAE under optimised conditions was an effective, low-cost and eco-friendly technique to recover biologically active polyphenols from 11 brown seaweed species.139Scopus© Citations 57 - PublicationCholecalciferol supplementation in heifer diets increases beef vitamin D concentration and improves beef tenderness(Elsevier, 2017-12)
; ; ; ; ; This study investigated the effects of cholecalciferol (vitamin D₃) supplementation on beef vitamin D activity, beef tenderness and sensory attributes. Thirty heifers were randomly allocated to one of three finishing dietary treatments [(T1) basal diet + 0 IU vitamin D₃; (T2) basal diet + 2000 IU vitamin D₃; and (T3) basal diet + 4000 IU vitamin D₃] for a 30 day period pre-slaughter. Vitamin D₃ supplementation linearly increased serum 25-hydroxyvitamin D₃ (25-OH-D3) concentrations (R2 = 0.48), Longissimus thoracis (LT) total vitamin D activity (R2 = 0.78) as well as individually vitamin D₃ (R2 = 0.84) and 25-OH-D₃ (R2 = 0.75). The highest vitamin D₃ inclusion diet (T3) had a 42% increase (P < 0.001) in LT vitamin D activity compared to the intermediate diet (T2) and a 145% increase over the lowest level diet (T1). Vitamin D₃ supplementation decreased LT shear (P < 0.05) force values after 14 days chilling. Sensory parameters were not affected (P > 0.05). In conclusion, through short-term vitamin D₃ supplementation of cattle diets, beef vitamin D activity can successfully be enhanced312Scopus© Citations 18 - PublicationEmerging food processing technologies and factors impacting their industrial adoption(Taylor & Francis, 2018-06-04)
; ; ; Innovative food processing technologies have been widely investigated in food processing research in recent years. These technologies offer key advantages for advancing the preservation and quality of conventional foods, for combatting the growing challenges posed by globalization, increased competitive pressures and diverse consumer demands. However, there is a need to increase the level of adoption of novel technologies to ensure the potential benefits of these technologies are exploited more by the food industry. This review outlines emerging thermal and non-thermal food processing technologies with regard to their mechanisms, applications and commercial aspects. The level of adoption of novel food processing technologies by the food industry is outlined and the factors that impact their industrial adoption are discussed. At an industry level, the technological capabilities of individual companies, their size, market share as well as their absorptive capacity impact adoption of a novel technology. Characteristics of the technology itself such as costs involved in its development and commercialization, associated risks and relative advantage, and level of complexity and compatibility influence the technology's adoption. The review concludes that a deep understanding of the development and application of a technology along with the factors influencing its acceptance are critical to ensure its commercial adoption.899Scopus© Citations 83 - PublicationCharacterization of dietary fucoxanthin from Himanthalia elongata brown seaweedThis study explored Himanthalia elongata brown seaweed as a potential source of dietary fucoxanthin which is a promising medicinal and nutritional ingredient. The seaweed was extracted with low polarity solvents (n-hexane, diethyl ether, and chloroform) and the crude extract was purified with preparative thin layer chromatography (P-TLC). Identification, quantification and structure elucidation of purified compounds was performed by LC-DAD-ESI-MS and NMR (1 H and 13 C). P-TLC led purification yielded 18.6 mg/g fucoxanthin with 97% of purity based on the calibration curve, in single-step purification. LC-ESI-MS (parent ion at m/z 641 [M + H-H2O] +) and NMR spectra confirmed that the purified band contained all-trans-fucoxanthin as the major compound. Purified fucoxanthin exhibited statistically similar (p > 0.05) DPPH scavenging capacity (EC 50:12.9 μg/mL) while the FRAP value (15.2 μg trolox equivalent) was recorded lower (p < 0.05) than the commercial fucoxanthin. The promising results of fucoxanthin purity, recovery and activity suggested that H. elongata seaweed has potential to be exploited as an alternate source for commercial fucoxanthin production.
441Scopus© Citations 58
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