Purification and identification of a novel heteropolysaccharide RBPS2a with anti-complementary activity from defatted rice bran

A novel heteropolysaccharide RBPS2a with anti-complementary activity was obtained from defatted rice bran by hot water extraction, ethanol precipitation, and purified by gel chromatography after anion-exchange chromatography. This fraction exhibited more potent anti-complementary activity than other polysaccharide fractions. RBPS2a was eluted as a single symmetrical narrow peak on high-performance gel-permeation chromatography (HPGPC) and the average molecular weight was 90,000 Da. We found RBPS2a contained 86.7% polysaccharide and 8.7% protein. The amino acid pattern showed that RBPS2a contained large amount of glutamic acid, arginine, aspartic acid, lysine, and alanine. The molar content of the above five amino acids constituted 59.31% of the total amino acids. Gas chromatography of absolute acid hydrolysate of RBPS2a suggested that it was composed of arabinose, xylose, glucose and galactose with a molar ratio of 4:2:1:4. The Fourier-transform infrared spectra (FT-IR) and ¹H, ¹³C NMR spectroscopy analysis revealed that RBPS2a had a backbone consisting of β-(1→3)-linked d-galacopyranosyl residues substituted at O-2 with glycosyl residues composed of α-d-xylose-(1→4)-α-d-arabinose-(1→ and α-d-glucose-(1→4)-α-d-arabinose-(1→ linked residues. Furthermore, some of the fractions extracted and purified from defatted rice bran exhibited strong anti-complementary activity. Among these fractions, the purified polysaccharide RBPS2a had the highest activity.     

Fractionation, separation, and identification of antioxidative peptides in potato protein hydrolysate that enhance oxidative stability of soybean oil emulsions

Abstract: The objective of the study was to identify the active peptides responsible for the antioxidant activity of potato protein hydrolysate (PPH). PPH was fractionated using ammonium sulfate precipitation; the efficacy of different fractions for scavenging 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS^{+ •}) radicals and inhibiting lipid oxidation (hexanal, TBARS) in soybean oil-in-water emulsions was investigated. Of all fractions, the fraction precipitated by 50% saturated ammonium sulfate (P50) exhibited the strongest ABTS^{+ •} scavenging activity and antioxidant activity. Active peptides based on the ABTS^{+ •} scavenging assay were isolated and purified by RP-HPLC and ultra performance liquid chromatography. Amino acid sequencing by tandem mass spectrometry identified Ser-Ser-Glu-Phe-Thr-Tyr and Ile-Tyr-Leu-Gly-Gln in P50 to be the dominant peptides that matched the sequences in metallocarboxypeptidase inhibitor and lipoxygenase 1, respectively.     

Effect of rosehip (Rosa canina L.) phytochemicals on stable free radicals and human cancer cells

BACKGROUND: The commercial development of plants as sources of antioxidants that can be used to enhance the properties of foods, for nutritional purposes and preservation as well as for prevention of oxidation‐related diseases, is currently of major interest. Rosehip (Rosa canina L.) is a rich source of vitamin C and polyphenols. RESULTS: Phytochemicals in rosehip tea were separated into three fractions: Fr1 (vitamin C, 39.17 mg kg^?1), Fr2 (flavonoids, 451.05 µg kg^?1) and Fr3 (phenolic acids, 504.69 µg kg^?1). Quercetin and ellagic acid were the most abundant polyphenolic compounds. Rosehip fractions, primarily rosehip flavonoids (EC₅₀ = 49 mg L^?1), showed high antioxidant activity towards 2,2‐diphenyl‐1‐picrylhydrazyl radicals (DPPH^?). Cell growth effects of rosehip fractions were assessed in HeLa, MCF7 and HT‐29 cell lines, with the lowest IC₅₀ values being determined for rosehip flavonoids, (80.63, 248.03 and 363.95 mg L^?1 respectively). However, the vitamin C fraction did not inhibit the growth of tested tumour cells. CONCLUSION: The results of this study confirm that vitamin C and flavonoids are responsible for the antioxidant activity of rosehip tea, while only polyphenols contribute to its antiproliferative activity. Copyright © 2011 Society of Chemical Industry     

Chemical characteristics and antioxidant activities of polysaccharide purified from the seeds of Plantago asiatica L.

BACKGROUND: A water‐soluble polysaccharide from the seeds of Plantago asiatica L. (P. asiatica L. polysaccharide, PLP) was extracted with hot water and purified by gel filtration chromatography. The chemical characteristics of PLP were determined by high‐performance gel permeation chromatography (HPGPC) and Fourier transform infrared (FTIR) spectroscopy. In addition, the antioxidant activities of PLP in vitro were evaluated using various test systems, including scavenging of 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH) radicals, scavenging of superoxide radicals generated by 1,2,3‐phentriol autoxidation, scavenging of hydroxyl radicals and inhibition of lipid peroxidation. RESULTS: The molecular weight of PLP was determined by HPGPC to be about 1894 kDa. PLP contained 29.2 g kg^?1 protein and 145.8 g kg^?1 uronic acid. The FTIR spectrum of PLP also revealed typical characteristics of a polysaccharide containing protein and uronic acid. Moreover, the results showed that PLP possessed antioxidant activities, but lower than those of ascorbic acid. CONCLUSION: PLP is an acid protein‐bound polysaccharide of high molecular weight, but its structure needs further study. The present results suggest that PLP could potentially be used as a natural antioxidant. Copyright © 2009 Society of Chemical Industry     

Effects of garlic oil on milk fatty acid profile and lipogenesis‐related gene expression in mammary gland of dairy goats

BACKGROUND: Garlic oil (GO) has blood lipid‐lowering effects. Milk fatty acid (FA) originates partly from plasma, and can be affected by the mammary lipogenesis. This study aimed to investigate GO effects on milk FA profile and mammary lipogenesis‐related gene expression. Early‐lactation goats were randomly allocated to four treatments with six goats each, and offered corn silage ad libitum and fixed amount of 0.79 kg day^?1 dry matter (DM) concentrate mixed with GO (0, 0.57, 1.14, 1.71 g kg^?1 DM) for 30 days consisting of 26‐day adaptation. RESULTS: Intake of corn silage reduced (P≤0.05) as GO level increased in the concentrate. Lipase activity and lactose content linearly increased, while non‐esterified FA concentration quadratically decreased with increasing GO level (P≤0.05). The proportions of short‐ and medium‐chain (C14:0, C15:0 and C16:0) and saturated FA decreased, whereas C18, cis9 trans11 conjugated linoleic acid (c9t11 CLA), t10c12 CLA, monounsaturated and polyunsaturated FA, and some ≥ C20 FA proportions increased in a linear manner with increasing GO level (P≤0.05). The mRNA abundance of genes remained unchanged (P > 0.1) as GO level increased. CONCLUSION: Garlic oil altered milk FA profile and these effects may not be related to the mammary lipogenesis‐related genes expression. © 2012 Society of Chemical Industry     

Effects of different forage:concentrate ratios in dairy ewe diets supplemented with sunflower oil on animal performance and milk fatty acid profile

The aim of this study was to evaluate the effect of different forage:concentrate (FC) ratios in dairy ewe diets supplemented with sunflower oil (SO) on animal performance and milk fatty acid (FA) profile, particularly focusing on trans C18:1 FA and conjugated linoleic acid (CLA). Sixty lactating Assaf ewes were randomly assigned to 6 treatments in a 3 × 2 factorial arrangement: 3 FC ratios (30:70, 50:50, and 70:30) and 2 levels of SO addition (0 and 20 g/kg of dry matter). Both the diet FC ratio and SO supplementation affected milk yield, but differences between treatments were small. Although the proportion of concentrate induced limited changes in milk FA profile, dietary SO significantly decreased saturated FA and enhanced total CLA. Furthermore, the incorporation of SO in ewe diets decreased the atherogenicity index value by about 25% and doubled the contents of potentially healthy FA such as trans-11 C18:1 and cis-9,trans-11 CLA. However, the inclusion of SO in a high-concentrate diet (30:70) could switch linoleic acid biohydrogenation pathways, resulting in a significant increase in trans-10 C18:1, trans-9,cis-11 C18:2, and trans-10,cis-12 C18:2 milk fat percentages.     

Isolation and chemical characterisation of a polysaccharide from green tea (Camellia sinensis L.)

BACKGROUND: To contribute towards understanding the relationship of structure and bioactivity, a protein‐bound acidic polysaccharide named TPC3‐1 was isolated and purified from low‐grade green tea (Camellia sinensis L.). The homogeneity and weight average molecular weight of TPC3‐1 was determined by agarose gel electrophoresis and high‐performance gel permeation chromatography. The monosaccharide and amino acid composition of TPC3‐1 were analysed by gas chromatography and an amino acid analyser. The molecular structure of TPC3‐1 was characterised by Fourier transform infrared spectroscopy, ¹³C nuclear magnetic resonance spectroscopy and atomic force microscopy. RESULTS: Based on the data obtained, the average peak molecular weight of TPC3‐1 was about 120 kDa. TPC3‐1 was composed of L ‐arabinose, D ‐ribose, D ‐xylose, D ‐glucose and D ‐galactose with a molar ratio of 4.9:2.2:3.1:1.8:1.0. Fifteen amino acids were identified as components of the polymer. The TPC3‐1 molecule was found to have an anomeric carbon sign of both α and β configurations and high‐branched chains. The network structure of TPC3‐1 was observed. CONCLUSION: The tea polysaccharide TPC3‐1 was an acid protein‐bound polysaccharide with an image of network structure. The results presented here will facilitate further study of the relationship between the chemical structure and biological role of tea polysaccharide. Copyright © 2008 Society of Chemical Industry     

Macrophage stimulating polysaccharide purified from peels of grape (Vitis labrusca)

To characterize the macrophage stimulating polysaccharide in grape (Vitis labrusca) peels, the active crude polysaccharide (VL-3) has been fractionated from the hot-water extract of grape peels. A macrophage stimulating polysaccharide-rich fraction (VL-3IIb-1-1) was purified from VL-3 by 3 successive column chromatographies on DEAE-Sepharose CL-6B, Sepharose CL-6B, and Sephacryl S-300. VL-3IIb-1-1 was eluted as a single peak on high performance liquid chromatography (HPLC) and its molecular weight was estimated to be 194 kDa. VL-3IIb-1-1 consisted mainly of Ara and Gal in addition to uronic acid (GalA+GlcA) (molar ratio 1.00:0.81:0.72). Methylation analysis indicated that VL-3IIb-1-1 consisted mainly of terminal Araf, 4- or 5-linked Ara, 2,4-branched Rha, 6- or 3,4- or 3,6-branched Gal, and 3,4,6-branched Glc. Single radial gel diffusion also indicated that VL-3IIb-1-1 showed an intermediate reactivity with β-glucosyl-Yariv antigen. In addition, oral administration of VL-3IIb enhanced the stimulatory responses of macrophage stimulating activity ex vivo. Therefore, VL-3IIb-1-1 purified from grape peels is suggested to be pectic polysaccharide with arabino-3,6-galactan, and it is assumed that VL-3IIb-1-1 plays an important role for expression of its activity.     

Seasonal changes of CLA isomers and other fatty acids of milk fat from grazing dairy herds in the Azores

BACKGROUND: Season of the year associated with dietary changes has been recognized as a factor implicated in milk fat fatty acid (FA) profile in dairy cows. However, a lack of information exists concerning cows grazing all year round as is practiced in the Azores, where cows are supplemented in winter with maize silage plus concentrates, while in spring the higher grass allowance only requires supplementation with concentrate. The main objective of this study was to detect any seasonal variation of FA profile of milk fat from milk sampled in bulk tanks of 12 Azorean dairy herds. RESULTS Compared to winter milk, milk fat from spring presented a higher proportion of CLA cis‐9,trans‐11 (14.3 versus 9.6 g kg^?1 FA), C18:1 trans‐11 (32 versus 22 g kg^?1 FA), C18:2 trans‐11,cis‐15 (3.7 versus 2.2 g kg^?1 FA), CLA trans‐11,cis‐13 (0.34 versus 0.23 g kg^?1 FA) and C18:3 n‐3 (5.7 versus 5.4 g kg^?1 FA). The C18:2 n‐6/C18:3 n‐3 ratio was lower (P < 0.05) in spring. Branched‐chain FA, except the anteiso‐C15:0, were higher in spring, while odd‐chain FA (C15:0) were higher in winter. CONCLUSION: Dairy herd management in the Azores presents a seasonal variation of milk fat FA composition, where the spring milk may present increased potential benefits for human consumers. Copyright © 2008 Society of Chemical Industry     

Antioxidant activity of compounds isolated from the pyroligneous acid, Rhizophora apiculata

The polyphenols (CPAE II) was isolated from the dichloromethane extract of the pyroligneous acid, Rhizophora apiculata by simultaneous acid base and solvent extraction method. Its qualitative and quantitative composition was studied by gas chromatography mass spectroscopy (GC/MS) and out of 57 peaks, 52 compounds were identified, representing 95.47% of the total polyphenols. The CPAE II was then fractionated to four fractions (F1–F4) by means of thin layer chromatography and silica gel column chromatography with dichloromethane, dichloromethane/chloroform/ethyl acetate mixture (8:1:1; 4:3:3, v/v/v), and ethyl acetate, respectively. The antioxidant properties of the CPAE II and the fractions were evaluated. Among the four fractions, fraction 1 (F1) was the most potent in DPPH radical scavenging activity and molybdenum (VI) reducing power. It was subjected to further purification by means of silica gel column chromatography with hexane, hexane/diethyl ether mixture (9:1, 6:1, 3:1, v/v), and diethyl ether, respectively. 2,6-Dimethoxyphenol (syringol) and dihydroxybenzenes (catechol and 3-methoxycatechol) were isolated and identified by GC/MS, ¹H NMR, ¹³C NMR spectral analyses, and confirmed by GC co-injection with authentic standards. Syringol, catechol and 3-methoxycatechol constitute 39.08, 4.21 and 1.10% of F1, respectively. Their antioxidant activities were evaluated by DPPH radical scavenging activity, ABTS radical cation scavenging activity, phosphomolybdenum and ferric reducing antioxidant power (FRAP). The trend in antioxidant capacity was similar in all the four assays, with dihydroxybenzenes > 2,6-dimethoxyphenols, although discrepancies in the ranking within the dihydroxybenzenes were present. These three compounds which showed significant antioxidant activities were isolated for the first time from the pyroligneous acid, R. apiculata.     

Preparation of reactive oxygen scavenging peptides from tilapia (Oreochromis niloticus) skin gelatin: optimization using response surface methodology

Abstract: Gelatin extracted from tilapia skin was hydrolyzed with Properase E. Response surface methodology (RSM) was applied to optimize the hydrolysis condition (temperature [T], enzyme‐to‐substrate ratio [E/S], pH and reaction time [t]), to obtain the hydrolysate with the highest hydroxyl radical (?OH) scavenging activity. The optimum conditions obtained were T of 44.2 °C, E/S of 2.2%, pH of 9.2, and t of 3.4 h. The predicted ?OH scavenging activity of the hydrolysate under the optimum conditions was 60.7%, and the actually experimental scavenging activity was 60.8%. The hydrolysate was fractionated by ultrafiltration, and 4 fractions were collected. The fraction TSGH4 (MW < 2000 Da) showed the strongest ?OH scavenging activity with the highest yield. Furthermore, reactive oxygen species (ROS) scavenging activities of TSGH4 with different concentrations were investigated in 5 model systems, including superoxide anion radical (?O₂), ?OH, hydrogen peroxide (H₂O₂), peroxynitrite (ONOO^?), and nitric oxide (NO?), compared with reduced glutathione (GSH). The results showed that TSGH4 significantly scavenged these ROS, and could be used as a functional ingredient in medicine and food industries.     

Structural characterization and antioxidant activities of 2 water-soluble polysaccharide fractions purified from tea (Camellia sinensis) flower

Abstract: The water‐soluble crude polysaccharide tea flower polysaccharide (TFP), obtained from tea (Camellia sinensis) flower by boiling‐water extraction and ethanol precipitation, was fractionated by Sephadex G‐100 column chromatography, giving 2 polysaccharide fractions termed TFP‐1 and TFP‐2. The structural features of TFP‐1 and TFP‐2 were investigated by high‐performance liquid chromatography (HPLC), gel‐permeation chromatography (GPC), rheometer, infrared (IR) spectra, nuclear magnetic resonance (NMR) spectroscopy, atomic force microscope (AFM), and scanning electron microscope (SEM). Results indicated that TFP‐1 was composed of glucose: xylose: rhamnose: galactose = 1.0:1.2:0.81:0.98 with a molecular weight of 167.5 KDa, while TFP‐2 comprised glucose: xylose: rhamnose: arabinose = 1.0:0.76:2.3:2.3 with a molecular weight of 10.1 KDa. The ¹H NMR revealed that TFP‐1 contained α‐L‐Rhap, α‐D‐Galp, α‐D‐GalpNAc, α‐D‐Xylp, α‐D‐Glcp, and β‐D‐Glcp residues, while TFP‐2 was illustrated to have α‐L‐Rhap, α‐L‐Arap, α‐D‐Xylp, α‐D‐Glcp, and α‐D‐GlcpNAc residues. Antioxidant activities of these fractions were investigated using various in vitro assay systems compared with ascorbic acid. In conclusion, TFP‐2 exhibited the higher antioxidant activities and could be explored as a novel potential antioxidant. Practical Application: At present, commonly low‐grade tea is preferred to extract the tea polysaccharide, to take full advantage of tea flower resource to extract polysaccharides can greatly reduce the cost of tea products. Thus, the search for plant‐derived biomaterials from this study could generate natural value‐added products from underutilized tea plant waste and used as a medicinal agent against chronic health problems, such as cancers, aging, and atherosclerosis caused by reactive free radicals that produced from oxidation.     

Isolation and Identification of Phenolic Antioxidants in Black Rice Bran

Black rice bran contains phenolic compounds of a high antioxidant activity. In this study, the 40% acetone extract of black rice bran was sequentially fractionated to obtain 5 fractions. Out of the 5 fractions, ethyl acetate fraction was subfractionated using the Sephadex LH‐20 chromatography. The antioxidant activity of phenolic compounds in the extracts was investigated by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical assay, 2,2‐azino‐bis‐(3‐ethylenebenzothiozoline‐6‐sulfonic acid) (ABTS) radical cation assay, reducing power. The subfraction 2 from ethyl acetate fraction had the highest total phenolic contents (TPC) (816.0 μg/mg) and the lowest EC₅₀ values (47.8 μg/mL for DPPH radical assay, 112.8 μg/mL for ABTS radical cation assay, and 49.2 μg/mL for reducing power). These results were 3.1, 1.3, and 2.6 times lower than those of butylated hydroxytoluene (BHT), respectively. At a concentration of 100 μg/mL, the antioxidant activity and TPC of various extracts was closely correlated, with correlation coefficients (R²) higher than 0.86. The major phenolic acid in subfraction 2 was identified as ferulic acid (178.3 μg/mg) by HPLC and LC‐ESI/MS/MS analyses. Our finding identified ferulic acid as a major phenolic compound in black rice bran, and supports the potential use of black rice bran as a natural source of antioxidant.     

Antioxidant activity of the ethanolic extract from the bark of Chamaecyparis obtusa var. formosana

BACKGROUND: Chamaecyparis obtusa var. formosana (Taiwan hinoki) is an endemic conifer in Taiwan and the purpose of this study is to evaluate the antioxidant activity of various fractions obtained from the bark of this plant material. The ethanolic extract of the bark was sequentially separated into three fractions, including n‐hexane, ethyl acetate and ethanol soluble fractions, by liquid–liquid partition. Then the antioxidant activities of crude extract and three fractions along with 13 subfractions obtained from the ethyl acetate (EA) soluble fraction were tested for several antioxidant assays. RESULTS: The total phenolic content of the samples varied from 27.71 to 102.86 mg GAE g^?1 dry weight for fractions, and from 49.94 to 206.46 mg GAE g^?1 for subfractions (where GAE is milligrams of gallic acid per gram of extract). The Trolox equivalent antioxidant capacity (TEAC) ranged from 0.15 to 0.26 mmol L^?1 Trolox equivalents. The EA soluble fraction was found to be the best antioxidant‐rich fraction in terms of DPPH and reducing power assays. With further data analysis it was found that there was a positive correlation between the total phenolic content of extracts and TEAC is R² = 0.61. CONCLUSION: Results from various antioxidant assays showed that the EA fraction possessed strong antioxidant activity. This would provide additional information about the antioxidant activity of bark extract of this plant species. Copyright © 2008 Society of Chemical Industry     

Evaluation of Citrus aurantifolia peel and leaves extracts for their chemical composition,antioxidant and anti‐cholinesterase activities

BACKGROUND: The replacement of synthetic antioxidants by safe natural antioxidants fosters research on the screening of vegetables and food as sources of new antioxidants. Moreover, oxidative degeneration of cells is associated with neurodegenerative diseases such as Alzheimer's disease. On the basis of these considerations this work aimed to investigate the antioxidant properties [by using the diphenyl picryl hydrazyl, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) and ferric reducing ability of plasma assays, and the β‐carotene bleaching test] and the anti‐cholinesterase activity of Citrus aurantifolia peel and leaves from different areas of growth. RESULTS: Methanol extracts of the peel and leaves demonstrated the strongest radical scavenging activity. A similar trend was observed with the reducing ability, with values from 112.1 to 146.0 µmol L^?1 Fe(II) g^?1. The relationship between phenol and flavonoid contents and antioxidant activity was statistically investigated. Based on analysis by high‐performance liquid chromatography, the most abundant flavonoids found in C. aurantifolia extracts were apigenin, rutin, quercetin, kaempferol and nobiletin. n‐Hexane fractions of both peel and leaves showed a good acetylcholinesterase inhibitory activity with IC₅₀ values in the range 91.4‐107.4 µg mL^?1. Gas chromatography‐mass spectrometry analysis revealed the presence of monoterpenes and sesquiterpenes as most common components. CONCLUSION: The findings of this study suggest a potential use of C. aurantifolia peel and leaves for supplements for human health. Copyright © 2012 Society of Chemical Industry     

Isolation,characterisation and sulphation of soluble polysaccharides isolated from Cucurbita maxima

Using hot water extraction, a large number of polysaccharides were obtained from Cucurbita maxima. A DEAE‐Sepharose CL‐6B chromatography column was used to isolate the major polysaccharides from C. maxima. Two fractions were obtained (LP2‐1 and LP2‐2). LP2‐1 and LP2‐2 consisted of neutral polysaccharides (MW: 1.02 × 10⁴ and 4.32 × 10⁸ g mol^?1, respectively) comprised mainly of galactose units. Analyses by FT‐IR spectrometry, partial acid hydrolysis, periodate oxidation, Smith degradation and GC‐MS indicated that LP2‐1 consisted of 85.3% (1→4) glycosidic linkages and 1.7% (1→3) or (1→6) glycosidic linkages. The LP2‐1 backbone consisted of (1→4)‐linked galactose units, which occasionally branched at O6 or O3. The branches were composed of (1→4)‐linked galactose and terminated with galactose (13%). Two sulphated derivatives (SLP2‐1 and SLP2‐2) with variable degrees of sulphation (DS) were obtained by the sulphur trioxide–pyridine method, without degradation of the polysaccharide. DS of PL2‐1 and PL2‐2 was 0.19 and 0.20, respectively.     

Influence of pH on colour and iron content of peptide fractions obtained from bovine Hb concentrate hydrolysates

The effect of pH on colour and iron content (Fe) of peptide fractions obtained from bovine haemoglobin concentrate (BHC) hydrolysates was studied. Four hydrolysates were obtained using three enzymes: Protex‐6‐L (P), Fungal–Protease–Concetrate (FC) and Flavourzyme (F). BHC and its hydrolysates (P, FC, P + F, FC + F) were fractioned at pH 4.5, 7.0 and 9.5. Solubility and Fe from different fractions were measured. Correlations between CIELAB colour parameters and Fe from different fractions were analysed. The colour from different fractions varied from red to yellow (a* and b* positives). Lightness values (L*) ranged from twenty‐four to seventy. FC4.5 and FC + F4.5 fractions were the clearest and yellow (higher L*, b*, h), while BHC9.5 and P + F9.5 fractions had the lowest values of L*, b* and h. There was an inverse linear relationship between b* and L* parameters and Fe from fractions. This relationship could be associated with the pH of extraction. As pH increases Fe significantly increases and lower b* and L* values were obtained.     

Effects of L‐carnitine supplementation to diets with different fat sources and energy levels on fatty acid composition of egg yolk of laying hens

BACKGROUND: The present study was carried out to determine the effects of feeding diets with two different levels of metabolisable energy (ME) (11.51 or 10.88 MJ ME kg^?1 diet) and three different sources of fat (palm oil, sunflower oil or fish oil) with or without supplemental L ‐carnitine (0 or 500 mg kg^?1 diet) on the fatty acid (FA) composition of egg yolk and the passage of n3 polyunsaturated FAs to egg yolk in laying hens. RESULTS: The ∑n3, particularly C22:6n‐3, FA contents of egg yolk were significantly reduced by adding of L ‐carnitine (C2) to different fat sources (P < 0.01). The ratio of n6/n3 was reduced from 53.77 to 17.72 in eggs yolks when ME was lowered in the diet with C2‐sunflower oil (SFO) whereas it was enhanced from 2.19 to 9.31 in C2‐E2 (low energy) diet with fish oil (FO) (P < 0.001). The diet with E2 or C2 containing FO resulted in a decrease of the C22:5n‐3, C22:6n‐3 and ∑n3 FA contents of egg yolk (P < 0.001). On the other hand, supplementation of C2 to diets with SFO or palm oil (PO) caused to a decrease in the C22:6n‐3 and ∑n3 FA contents of egg yolk (P < 0.01). A significant increase of the ratio of n6/n3 in egg yolk can be seen by feeding with E2 diet by adding of C2 to all fat sources like in E1 (normal energy) diet (P < 0.001). CONCLUSION: Dietary treatments resulted in major changes in FA composition of egg yolk. The supplemental C2 in diet decreased the C22:5n‐3, C22:6n‐3 and ∑n3FA contents in egg yolk. The use of FO in diets with E2 significantly reduced the passage rate of C22:6n‐3 FA to egg yolk. Copyright © 2008 Society of Chemical Industry     

Fatty acid profiles, antioxidant compounds and antiradical properties of Pinus halepensis Mill. cones and seeds

BACKGROUND: Pinus halepensis (Aleppo pine) is a widespread tree that can be found in both natural and urban environments. A discrimination study based on the antioxidant compounds, antioxidant capacity and fatty acid (FA) profile of P. halepensis cones (PHC) and seeds (PHS) was performed. RESULTS: The total amount of phenols was about 72‐fold higher in PHC extract than in PHS extract (P < 0.001). Anthocyanin and carotenoid contents were 10‐ and 12‐fold higher respectively in PHC extract. PHC and PHS extracts at a concentration of 1 mg mL^?1 differed significantly in free radical‐scavenging activity on 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH^?) (86.65 vs 16.97%). PHC had higher antioxidant ability on 2,2′‐azino‐bis(3‐ethylbenzothialozine‐6‐sulfonic acid) radical cation (ABTS^?+) than PHS (EC₅₀ 0.368 vs 2.345 mg mL^?1). The FA profile of PHC oil revealed its richness in saturated FAs (41.5%) and high levels of trans FA isomers, with a predominance of trans,trans ‐linoleic acid (4.74%). However, polyunsaturated FAs in PHS oil represented more than 64% of total FAs. CONCLUSION: PHC showed important antioxidant activities as well as high levels of bioactive compounds. Thus PHC is a potential source of natural antioxidants that may afford several health benefits. However, the lipid extract of PHS seems to have more nutritional value as a polyunsaturated oil than that of PHC, which is high in saturated and trans FAs. Copyright © 2011 Society of Chemical Industry     

Fumonisin B1 induced compositional modifications of the renal and hepatic membrane lipids in rats – Dose and exposure time dependence

ABSTRACT

Male Wistar rats were intraperitoneally dosed with fumonisin B1 (FB₁; 0, 20, 50 and 100 mg kg^?1 dietary dose equivalent) for 5 & 10 days to assess dose- and time-dependent effects on renal and hepatic phosphatidylcholine (PC), phosphatidylinositol (PI) and phosphatidylethanolamine (PE) fatty acid (FA) profiles. Renal PC showed increasing FA saturation (SAT) after 5 days; after 10 days polyunsaturation (PUFA) decreased markedly (Σ n3 (total n3), Σ n6, PUFA, unsaturation index (UI) and average FA chain length (ACL)), mostly with linear dose response. In the PI FAs similar changes were observed, decreasing monounsaturated FA, PUFA, UI and ACL (5 & 10 days), while the PE fraction was responsive in Σ n6 (↓) and SAT (↑), but only after 5 days (without dose response for both PI & PE). Liver PC exhibited increasing saturation (C16:0), decreasing polyunsaturation (C20:3 n6 [dihomo-γ-linolenic acid, DGLA]; C20:3 n3); the PI FA profile showed similar alterations after 5 days. PC & PI FA failed to respond in a dose-dependent manner to FB₁. In PE FA profile DGLA decreased, with a decrease of the total n6 FA proportion and dose-dependent increase of n3 FAs. Results revealed expressed renal sensitivity, supporting our earlier published results in terms of oxidative stress and histopathological modifications.