Effect of different pasteurization conditions on bioactivities of Lupinus albus protein isolates

Lupin protein isolate was extracted following the procedure in European Patent (EP 1024 706 B1) in order to use lupin protein for food and pharmaceutical applications. The acid insoluble/neutral pH soluble protein isolate was pasteurized at 65-125 °C for 10-1000 s. The objective of this study is finding out reasonable pasteurization condition for food use, or for good bioactivities like radical scavenging, angiotensin converting enzyme inhibition, and bile acid binding activity. Pasteurization at 65 °C for 10 s did not reduce the microbial count of the protein sufficiently for use in foods. The chemical composition of lupin protein isolates had no change by various pasteurization. The angiotensin converting enzyme inhibition decreased and the DPPH radical scavenging capacity increased after high temperature treatment at 125 °C. The sodium cholate binding capacity was not affected by tested conditions. Pasteurization at higher temperature is useful for producing selective bioactive fractions with suitable microbiological properties.     

Cholesterol-lowering effect of whole lupin (Lupinus albus) seed and its protein isolate

This study describes the hypocholesterolaemic effect of whole lupin and its protein in hamsters. The diets were: casein (control group HC), lupin protein isolate (group HPI) and whole lupin seed (group HWS). Diets from HPI and HWS promoted a significant reduction of total cholesterol and non-HDL cholesterol in the hamsters’ plasma as compared with HC. The true digestibility of HPI and HC groups were similar and differed significantly from the HWS one, which in turn showed a significant difference in total sterol excretion as compared to the former groups. Histological analysis of the liver revealed that animals fed on HPI and HWS diets presented a low level of steatosis (level 1) as compared to the ones fed on HC diet (level 4). Our findings demonstrate that protein isolate from Lupinus albus from Brazil has a metabolic effect on endogenous cholesterol metabolism and a protector effect on development of hepatic steatosis.     

Effect of genotype and environment on fatty acid composition of Lupinus albus L. seed

Six cultivars of Lupinus albus L. (white lupin) were grown in two subcontinental-climate environments and one Mediterranean-climate environment in Italy, to assess the influence of genotypic (G) and genotype × environment (GE) interaction effects on grain yield and grain content of oil, total saturated fatty acids (FAs), polyunsaturated FAs, monounsaturated FAs, and ω−3/ω−6 FA ratio. The variance of genotypic effects was much larger than the GE interaction variance for all variables, except for grain yield, indicating that oil content and FA composition of different varieties can be assessed reliably in just a few test environments. Gas-chromatographic analyses highlighted that linoleic acid and α-linolenic acid were in the range 1.76–4.76 mg/g flour (7.79–15.81% of total FAs) and 1.17–3.14 mg/g flour (5.40–10.36% of total FAs), respectively. As a consequence, the analysed lupin seeds exhibited a very favourable ω−3/ω−6 FA ratio, ranging from 0.49 to 0.79.     

Fat and fatty acids of white lupin (Lupinus albus L.) in comparison to sesame (Sesamum indicum L.)

The study was undertaken to compare fat and fatty acid profiles in white lupin (Lupinus albus ssp. albus) and sesame (Sesamum indicum L.), representing two different families, Fabaceae and Pedaliaceae. Fat levels were 10.74% and 55.44% in seeds of white lupin and sesame, respectively. The results indicated that oleic, linolenic and arachidic acids in seed fat were higher in white lupin than in sesame cultivars. Oleic acid was the predominant fatty acid in white lupin, whereas linoleic acid was predominant in sesame. Fat content (%) was statistically significantly correlated with linoleic, linolenic and arachidic acids at the genotypic level. The fatty acid composition of white lupin is useful for human consumption. Although oil content of white lupin was lower than that of sesame, white sweet lupin could be improved.     

Nutritional and functional properties of Vicia faba protein isolates and related fractions

The goal of this research was the characterisation of Vicia faba (broadbean) protein isolates and related fractions in order to determine whether this grain legume could be used for production of high quality protein products and other fractions rich in functional components. Alkaline extraction of the defatted seed flour, followed by precipitation at the isoelectric pH, yielded a 92% protein isolate with a high oil absorption capacity. The contents of the favism-inducing glycosides, vicine and convicine, in the isolate were reduced by more than 99% as compared to the original flour, although the amino acid composition was similar to that of the flour. Some of the by-products of protein isolate production may also be of interest from a nutritional and functional point of view. Thus, the oil resulting from hexane extraction of the flour is rich in unsaturated fatty acids, and polyphenols (resulting from extraction of the defatted flour with acetone) showed a high ABTS radical-scavenging activity. In addition, the solid residue (resulting from protein solubilisation) was high in fibre and showed good water absorption. These results show good nutritional and functional properties in V. faba protein isolates and related fractions, which may favour the revalorisation of this traditional bean crop.     

Protein isolates from two Mediterranean legumes: Lathyrus clymenum and Lathyrus annuus. Chemical composition,functional properties and protein characterisation

Protein isolates were analysed from two Mediterranean legumes, Lathyrus clymenum and L. annuus. Protein isolates were prepared by alkaline extraction, including sodium sulphite and acid precipitation of Lathyrus proteins at their isoelectric point (pH 4.5). The percentage of proteins recovered from L. annuus and L. clymenum flours during the preparation of the protein isolates was around 60%. Chemical composition, nutritional parameters, main functional properties and protein composition of Lathyrus protein isolates were studied. L. annuus and L. clymenum protein isolates contained 81.07% and 82.4% of proteins, respectively, and they have a balanced content of essential amino acids, except for sulphur amino acids, with respect to the FAO pattern. The in vitro protein digestibility increased in the protein isolates to 93% and 95% in L. annuus and L. clymenum, respectively. Functional properties were similar to those observed in other legumes protein isolates. These results confirm the interest of local crops as sources of high value protein products obtained after convenient protein extraction procedures and the removal of antinutritional components. These high added value protein isolates are of interest for the food industry and for the revalorisation of L. annuus and L. clymenum favouring the bioconservation of Lathyrus.     

Abietane diterpenoids from Isodon lophanthoides var. graciliflorus and their cytotoxicity

Seven new (1–7) and three known (8–10) abietane diterpenoids were isolated from the methanolic extract of the aerial parts of Isodon lophanthoides var. graciliflorus (Lamiaceae), a folk Chinese medicine and an herb for functional beverages. They were identified as 16-acetoxylsugiol (1), graciliflorin E (2), graciliflorin F (3), 15-O-methylgraciliflorin F (4), 15-hydroxy-20-deoxocarnosol (5), 3β-hydroxysempervirol (6), 15-hydroxy-1-oxosalvibretol (7), abieta-8,11,13-triene-14,19-diol (8), 6,12,15-trihydroxy-5,8,11,13-abietatetraen-7-one (9), and 3α-hinokiol (10) based on the spectroscopic data including COSY (correlated spectroscopy), HMBC (heteronuclear multiple bond correlation), and HR-ESI-MS (high-resolution electrospray ionization mass spectrometry). All the compounds except 10 were obtained from I. lophanthoides for the first time. Compounds 1, 2, 5, 6, 8, and 9 exhibited in vitro cytotoxicity against A549 (human lung adenocarcinoma), MCF-7 (human breast adenocarcinoma), and HeLa (human cervical carcinoma) cell lines with the IC₅₀ values of 1.79–52.67 μM.     

Characterisation of esterolytic activity from two wild mushroom species, Amanita vaginata var. vaginata and Tricholoma terreum

Characterisation of esterase activities from the edible mushroom species, Amanita vaginata var. vaginata and Tricholoma terreum, were investigated. Native electrophoresis of the crude extracts prepared from both mushroom samples showed the presence of esterolytic activities. The extracts had the greatest activity in the presence of p-nitrophenyl butyrate (pNPB) as a substrate. pH and temperature optima were found to be 8.0 and 30 °C for both enzymes, respectively. V_max and K_m values were determined as 14.2 U/l and 71 μM for A. vaginata var. vaginata and 34.6 U/l and 9.6 μM for T. terreum, respectively. The pH-stability profile showed a stationary line between 3.0 and 10.0 for both enzymes. The esterolytic activities from the extracts were maintained between 10 and 40 °C for 4 h and started to decrease at 50 °C. The effects of EDTA, NaN₃, DTT and PMSF on the enzyme activity were also investigated.     

Comparative study of the composition and thermal properties of protein isolates prepared from nine Phaseolus vulgaris legume varieties

Beans contain high amounts of protein and, as demonstrated with other legumes, may contain peptides with bioactive properties. Dozens of dry bean (Phaseolus vulgaris) varieties are grown in Canada, and many vary not only in terms of their protein content but also in their composition. In this study, the composition, molecular structure, and thermal properties of nine varieties of P. vulgaris were studied using electrophoresis, reversed-phase high-performance liquid chromatography (RP-HPLC), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy (FTIR). The predominant protein observed in each variety was vicilin. RP-HPLC chromatogram showed protein isolates (PIs) of white, great northern and black beans to have different profiles of low-molecular-weight proteins. Additionally, black bean PIs were missing proteins in the molecular mass (MM) range of 60 to 97 kDa. DSC analysis showed cranberry and light red kidney bean PIs to have significantly lower denaturation temperatures compared to the other varieties. RP-HPLC chromatograms of cranberry and light red kidney bean PIs were also very different. FTIR spectroscopy showed the predominant secondary structures in all varieties to be ??-sheets and random coils. Increasing the temperature from 25 °C to 95 °C resulted in a reduction in ??-sheet structures and an increase in the content of random coils and antiparallel ??-sheet structures. Overall there were no major dissimilarities observed in the FTIR profiles of the nine P. vulgaris varieties.     

TLC bioautography-guided isolation of antioxidants from fruit of Perilla frutescens var. acuta

Guided isolation through bioautography on TLC using 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) as a detection reagent led to the isolation of four antioxidant compounds from fruit of Perilla frutescens var. acuta. These compounds were identified as rosmarinic acid (1), luteolin (2), apigenin (3), and chrysoeriol (4), by means of UV, NMR, and ESI MS. All the compounds were isolated for the first time from the fruit of the plant. Compounds 1 and 2 showed significant DPPH scavenging capacities, with IC₅₀ values of 8.61 and 7.50 μM, respectively. Further quantitative HPLC analysis confirmed that compounds 1-4 are the predominant contributors to the free radical scavenging activity of the extract of P. frutescens var. acuta.     

Effects of hydroalcoholic α-galactoside extraction and phytase supplementation on the nutritive utilization of manganese,iron, zinc and potassium from lupin (Lupinus albus var. multolupa)-based diets in growing rats

The effects of α-galactoside removal, using a hydroalcoholic extraction process and phytase supplementation, on the digestive and metabolic utilization of total ash, Mn, Fe, Zn and K from Lupinus albus var. multolupa-based diets by growing rats were evaluated, using a balance technique, and compared to the results obtained using a casein–cystine control diet. The specific amount of minerals needed to complement those provided by the lupin flours and casein in order to reach the target requirements of the growing rat were supplemented as heme or non-heme iron sources or in the form of inorganic salts in the case of Zn or K. The nutritive utilization of total ash, Mn, Fe and Zn was higher from raw and α-galactoside-free lupin flour diets than from the casein–cystine control or the phytase-supplemented diets, whereas smaller differences were found regarding the nutritive utilization of K. Differences in mineral retention were reflected in changes of the mineral contents of some tissues, which varied among the different cations studied.     

Physicochemical and functional properties of the protein isolate and major fractions prepared from Akebia trifoliata var. australis seed

The physicochemical and functional properties of protein isolate (API) and major protein fractions prepared from Akebia trifoliata var. australis seed were investigated. The seed contained 38.83% of oil and 17.23% of protein. Albumin (51.65%) and glutelin (46.40%) were the predominant fractions in the protein component of the seed. The major amino acids were found to be glutamic acid and aspartic acid, while the contents of sulphur-containing amino acids and threonine were very low. One to eight distinct bands with molecular weight (MW) ranging from 12.0 to 50.0 kDa were displayed by SDS–PAGE. The solubilities of API, albumin and glutelin from seeds of the A. trifoliata var. australis were the lowest at pH 4.0–5.0. The high surface hydrophobicity indices of these three proteins were observed at pH 7.0, while the excellent emulsifying properties were displayed at pH 9.0. Circular dichroism measurements indicated that API, albumin and glutelin were rich in β-strand and random coil structures.     

Variations in essential oil and fatty acid composition during Myrtus communis var. italica fruit maturation

The essential oil and fatty acid composition of Myrtus communis var. italica fruit during its ripening was determined. The effect of the harvesting time on some physical properties of Myrtus fruits, fruit weight and moisture content, were significant. The increase of fruit weight (from 2.54 to 8.79 g% fruits) during ripeness was correlated positively with that of moisture content (from 28% to 72%). Fruit essential oil yields varied from 0.003% to 0.01% and showed a remarkable increase at 60 days after flowering to reach a maximum of 0.11%. Forty-seven volatile compounds were identified in fruit essential oils; 1,8-cineole (7.31–40.99%), geranyl acetate (1.83–20.54%), linalool (0.74–18.92%) and α-pinene (1.24–12.64%) were the main monoterpene compounds. Total fatty acid contents varied from 0.81% to 3.10% during fruit maturation and the predominant fatty acids were linoleic (12.21–71.34%), palmitic (13.58–37.07%) and oleic (6.49–21.89%) acids. The linoleic acid proportions correlated inversely with palmitic and oleic acids during all the stages of ripening.     

Determination of antioxidant activities of various extracts and essential oil compositions of Thymus praecox subsp. skorpilii var. skorpilii

The aim of this work is to examine the chemical composition and antioxidant activity of separated essential oils and different solvent extracts of Thymus praecox subsp. skorpilii var. skorpilii (TPS). The ethanol, acetone, methanol, hexane, aqueous extracts and separated essential oils of TPS were assessed for their antioxidant activities. Antioxidant activities were evaluated by reduction of Mo(VI) to Mo(V), reducing power, superoxide scavenging activity, free radical-scavenging activity, metal chelating activity, linoleic acid peroxidation, hydrogen peroxide scavenging activity and peroxide scavenging activity. Essential oils were characterized in total to be 41 components, whereas 9 components were isolated by column chromatography for antioxidant activity. TPS essential oil was found to contain thymol (40.31%) and o-cymene (13.66%) as the major components. The ethanol, methanol and water extracts exerted significant free radical-scavenging activity. The methanol and water extracts displayed highest superoxide scavenging activity. The water extract has the highest total phenolics (6.211 mg gallic acid (GAE)/g DW) and flavonoids (0.809 mg quercetin/g DW).     

Accumulation and antioxidant activity of secondary carotenoids in the aerial microalga Coelastrella striolata var. multistriata

The growth and nitrate uptake of the aerial microalga Coelastrella striolata var. multistriata, which was isolated from the surface of rocks, were characterized under a variety of conditions in this study. The maximum specific growth rate of the alga, having prominent inorganic nitrogen uptake in the fresh medium, was 0.30 d⁻¹, as calculated in the growth logarithmic phase. It was also shown that the alga had abilities to be reddish orange to green colour (depending on the nitrogen source concentration in the medium) and to synthesize very high amounts of a complex mixture of carotenoids, such as canthaxanthin, astaxanthin and β-carotene. The reddish orange cells of the alga could accumulate 56.0 mg of major secondary carotenoids per g biomass. In the content of carotenoids, canthaxanthin, astaxanthin and β-carotene in the cells were 47.5, 1.5, and 7.0 mg/g dwc, respectively. Additionally, it was shown that the algal extract containing those carotenoids had an antioxidant potential in lipid foods. In the near future, the aerial microalga C. striolata var. multistriata will be used as a functional material in a variety of commercial applications, such as feed supplements, natural antioxidants and food dyes.     

Molecular subtyping and virulence gene analysis of Listeria monocytogenes isolates from food

A total of 67 Listeria monocytogenes isolates from 698 raw meat samples were characterized for molecular serogroup identification and antimicrobial susceptibility. Approximately one third (32.8%) of the isolates belonged to molecular serogroup 1/2a, 3a, followed by 1/2c, 3c (26.9%), 1/2b, 3b, 7 (22.4%), 4b, 4d, 4e (16.4%) and 4a, 4c (1.5%). Most of the L. monocytogenes isolates were susceptible to 14 antimicrobials tested but several were resistant to tetracycline, ciprofloxacin and nitrofurantoin. An additional 30 L. monocytogenes isolates from chicken and produce in our collection were also included to determine the presence of significant virulence markers. All 97 isolates carried inlC and inlJ except for a lineage III isolate 110-1. Most Listeriolysin S (LLS)-carrying isolates (11/12) belonged to lineage I, whereas the remaining one isolate belonged to lineage III. Five 4b, 4d, 4e isolates including two from turkey and three from produce belonged to Epidemic Clone I (ECI). Four molecular serogroup associated mutation types that lead to premature stop codons (PMSCs) in inlA were identified. PFGE and inlA sequence analysis results were concordant, and different virulence potential within 1/2a, 3a and 4b, 4d, 4e isolates were observed. The study revealed that a subset of isolates from meat and produce belonged to ECI, harbored inlC, inlJ and LLS, and produced full length InlA, suggesting that they be capable of causing human illness.     

Aromatic series in sherry wines with gluconic acid subjected to different biological aging conditions by Saccharomyces cerevisiae var. capensis

Wines from healthy grapes supplemented with gluconic acid were subjected to biological aging under two experimental conditions. The first one was carried out under flor yeast velum as in the traditional biological aging and the second one under submerged cultures. The highest gluconic acid consumption was observed in aged wines in submerged cultures. Nine aromatic series were obtained by grouping the 48 volatile compounds quantified in wines. The aroma profile based on the aromatic series allows comparison of the changes due to the gluconic acid consumption and the changes due to the different aging conditions assayed. Only the herbaceous and fatty series showed diminished values of consequence of gluconic acid consumption. The fatty, herbaceous and roasty series show highest values, whereas the fruity, floral, solvent and medicinal series reached lower values in the submerged cultures assay. The application of the assay conditions to winemaking can reduce the gluconic acid concentration in wines obtained from rotten grapes.     

Essential oils of Zingiber officinale var. rubrum Theilade and their antibacterial activities

The essential oils obtained by hydrodistilation of the leaves and rhizomes of Zingiber officinale var. rubrum Theilade were analysed by capillary GC and GC–MS. Forty-six constituents were identified in the leaf oil, while 54 were identified in the oil from the rhizomes. The leaf oil was clearly dominated by β-caryophyllene (31.7%), while the oil from the rhizomes was predominantly monoterpenoid, with camphene (14.5%), geranial (14.3%), and geranyl acetate (13.7%) the three most abundant constituents. The evaluation of antibacterial activities using the micro-dilution technique revealed that both the leaf and rhizome oils were moderately active against the Gram-positive bacteria Bacilluslicheniformis, Bacillus spizizenii and Staphylococcus aureus, and the Gram-negative bacteria Escherichia coli, Klebsiella pneumoniae and Pseudomonas stutzeri.     

Sucrose hydrolysis by gelatin-immobilized inulinase from Kluyveromyces marxianus var. bulgaricus

The crude cell-free medium from a culture of Kluyveromyces marxianus var. bulgaricus was immobilized in a gelatin-water support, with an immobilization yield of 82.60% for inulinase activity. The optimum pH for both free and immobilized inulinase was the same (3.5) and the optimum temperatures were 55 °C for the free and 60 °C for the immobilized enzyme. The Arrhenius plots were linear and activation energies were 56.20 (free enzyme) and 20.27 kJ/mol K (immobilized enzyme). The kinetic parameters were calculated by Lineweaver–Burk plots and the V_max and K_m were 37.60 IU/mg protein and 61.83 mM for the free inulinase and 31.45 IU/mg protein and 149.28 mM for the immobilized enzyme, respectively. The operational stability of the immobilized inulinase was studied in a continuous fixed-bed column reactor for 33 days, at the end of which the sucrose conversion was 58.12%.     

Antioxidant and metal chelating activities of Phaseolus vulgaris L. var. Jamapa protein isolates, phaseolin and lectin hydrolysates

A search in a database of potential bioactive short sequences in food proteins reveals that bioactive peptides with a variety of beneficial effects for cardiovascular health are present in the sequence of common bean proteins, including bioactive sequences with antioxidant properties. A protein isolate, the storage protein phaseolin and a lectin extract from Phaseolus vulgaris L. var. Jamapa, were hydrolyzed by treatment with pepsin and pancreatin in order to investigate the possible release of peptides with antioxidant and metal chelating properties. Antioxidant activity was determined in Caco-2 cells exposed to a free radical generator, and iron and copper chelating activities were determined using colorimetric methods. The highest antioxidant activity, 71% inhibition, was found in the hydrolyzed protein isolate. Copper and iron chelating activities were highest in the lectin and phaseolin hydrolysates, 53% and 81%, respectively. Thus, experimental data indicates, as suggested by the database search, that antioxidant peptides are abundant in pepsin-pancreatin hydrolysates, which may represent a valuable health-promoting property in common bean.