Emulsifying and foaming properties of Phaseolus vulgaris and coccineus proteins

Protein isolates from two Phaseolus cultivars, common bean (Phaseolus vulgaris L.) and scarlet runner bean (Phaseolus coccineus L.), were prepared by wet extraction methods (isoelectric precipitation – 4000 rpm, ultrafiltration, extraction with NaCl 2%, and isoelectric precipitation – 9900 rpm). The protein isolates were characterized by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and then evaluated for their solubility. The emulsion stability of emulsions produced at pH 7.0 and 5.5 with 1% or 2% or 3% w/v protein isolate was evaluated by average droplet size diameter, viscosity and creaming measurements. Emulsions with 1% protein content were unstable through storage. Emulsions with 3% w/v protein isolate concentration, extracted by ultrafiltration at pH 5.5 from both cultivars, were flocculated; this was more pronounced for coccineus isolates. The foaming properties, for the respective foams, were investigated. Foams with 1% w/v protein showed little foaming ability Ultrafiltration isolates produced more foam, which was especially stable at pH 5.5.     

Content of flavonols in Italian bean (Phaseolus vulgaris L.) ecotypes

Methanol extracts of seeds from 23 accessions of 3 Phaseolus vulgaris ecotypes (“Sarconi”, “Lamon”, “Zolfino del Pratomagno”), grown in different Italian regions (Basilicata, Veneto, Tuscany) were analyzed for their flavonoid content. Flavonoid glycosides were found in the seed coat from ten accessions of the “Zolfino” ecotype and in one accession of the “Sarconi” ecotype. From highest to lowest concentration these compounds were kaempferol 3-O-glucoside (compound 2), kaempferol 3-O-xylosylglucoside (compound 1) and a not completely identified kaempferol monoglucoside (compound 3). Total flavonol content varied from 0.19 to 0.84 g/kg of seed fresh weight. A great variability in the total flavonol content, being between 18% and 50%, and in the relative abundance of different kaempferol derivatives was observed for the same genotypes sampled in the original locations in the 2001–2003 period. Fluctuation in flavonol content suggests that further researches are necessary for an exhaustive comprehension of physiological mechanisms influencing the expression of these phenolic compounds. Obtained results evidenced that some Italian bean ecotypes may be an important source of functional compounds as kaempferol glycosides.     

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.     

In vitro and in vivo protein hydrolysis of beans (Phaseolus vulgaris) genetically modified to express different phaseolin types

Experiments were conducted to study whether phaseolin type could influence proteolysis susceptibility and nutritional value of total bean protein. The DOR-390 bean cultivar was genetically modified to express different phaseolin types (S, T or I). Beans were soaked and autoclaved. A sequential hydrolysis was carried out in vitro with pepsin and pancreatin. Differences in the degree of protein hydrolysis among bean lines started at 30 min and remained until 240 min, with the S bean proteins presenting lower values (P < 0.05). Subsequently, rats were fed with diets containing beans expressing different phaseolin types as the only source of protein for N digestibility and nutritional value determination. No differences (P > 0.05) in ileal protein digestibility and rat growth were observed. In conclusion, the differences in in vitro hydrolysis between bean lines expressing different phaseolin types had no consequences on growth and N retention in rats.     

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.     

Common bean (Phaseolus vulgaris L.) hydrolysates inhibit inflammation in LPS-induced macrophages through suppression of NF-κB pathways

The objectives of this study were to evaluate the antioxidant capacity of protein hydrolysates of the common bean (Phaseolus vulgaris L.) varieties Negro 8025 and Pinto Durango and determine their effect on the markers of inflammation in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Cell viability was determined and the percentage of viable cells was calculated and concentrations that allowed >80% cell viability were used to determine the markers of inflammation. Alcalase hydrolysates and pepsin–pancreatin hydrolysates showed the highest antioxidant capacity after 80 and 120 min of hydrolysis, respectively. Alcalase hydrolysates of the common bean Pinto Durango at 120 min inhibited inflammation, with IC₅₀ values of 34.9 ± 0.3, 13.9 ± 0.3, 5.0 ± 0.1 and 3.7 ± 0.2 μM, while var. Negro needed 43.6 ± 0.2, 61.3 ± 0.3, 14.2 ± 0.3 and 48.2 ± 0.1 μM for the inhibition of cyclooxygenase-2 expression, prostaglandin E₂ production, inducible nitric oxide synthase expression and nitric oxide production, respectively. Also, hydrolysates significantly inhibited the transactivation of NF-κB and the nuclear translocation of the NF-κB p65 subunit. In conclusion, hydrolysates from the common bean can be used to combat inflammatory and oxidative-associated diseases.     

Deterrent and insecticidal properties of bean seed (Phaseolus vulgaris L.) whole meal or protein extract incorporated into the diet of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

Callosobruchus maculatus, a pest that causes serious damage to chickpea Cicer arietinum, cannot develop in the seeds of Phaseolus or Vigna spp. which contain lectins. The insecticidal activity towards C. maculatus in these seeds is attributed both to lectins with specific affinity to N-acetylglucosamine, the major component of insect chitin, and to alpha-amylase inhibitors (lectin-like proteins). The insecticidal properties of bean meal or bean protein extracts from different sources towards different pest species are variable and need to be experimentally evaluated. The main objective of this study was to determine through a feeding trial on artificial chickpea seed the potential of bean seed meal from a wild bean Vigna caracalla, four varieties of Phaseolus vulgaris, and of a protein extract of P. vulgaris seed, to alter different life history traits of C. maculatus. The chickpea weevil was set up on artificial chickpea seeds containing different amounts of bean meal to observe the effects on female oviposition, percentage of development to adulthood and juvenile development time. These traits were combined in a composite index measuring the alteration of the multiplication rate of C. maculatus fed on artificial seed. The activity of lectin-like extracts was observed on chickpea artificial seed spiked with bean seed extract. Incorporation of bean flour at a rate of 10 and 20% in chickpea artificial seed significantly decreased C. maculatus female fecundity, percentage of adult emergence, and greatly increased the development time. Feeding trials with protein extracts of P. vulgaris reduced fecundity and survival of C. maculatus. Incorporation of 10% V. caracalla bean seed meal in chickpea artificial seed, reduced the multiplication potential of C. maculatus by over 90% showing that bean seed lectin extracts are worthy of further investigation for post-harvest infestation control.     

The polyphenolic profiles of common bean (Phaseolus vulgaris L.)

Based on the phenolic profiles obtained by high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS), 24 common bean samples, representing 17 varieties and 7 generic off-the-shelf items, belonging to ten US commercial market classes can be organized into six different groups. All of them contained the same hydroxycinnaminic acids, but the flavonoid components showed distinct differences. Black beans contained primarily the 3-O-glucosides of delphinidin, petunidin and malvidin, while pinto beans contained kaempferol and its 3-O-glycosides. Light red kidney bean contained traces of quercetin 3-O-glucoside and its malonates, but pink and dark red kidney beans contained the diglycosides of quercetin and kaempferol. Small red beans contained kaempferol 3-O-glucoside and pelargonidin 3-O-glucoside, while no flavonoids were detected in alubia, cranberry, great northern, and navy beans. This is the first report of the tentative identification of quercetin 3-O-pentosylhexoside and flavonoid glucoside malonates, and the first detailed detection of hydroxycinnamates, in common beans.     

Quantification of the polyphenolic fraction and in vitro antioxidant and in vivo anti-hyperlipemic activities of Hibiscus sabdariffa aqueous extract

In the present study the quantification of the polyphenolic fraction, anthocyanins and other polar compounds, the antioxidant capacity and the anti-hyperlipemic action of the aqueous extract of Hibiscus sabdariffa has been achieved. Seventeen compounds were successfully quantified either by HPLC-DAD or HPLC-ESI-TOF-MS. Six of them were directly quantified by their corresponding standards, whereas the rest were indirectly quantified as equivalents using standards of similar compounds. The antioxidant capacity have also been estimated by comparing different assays, i,e, Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and measurement of thiobarbituric acid reacting substances (TBARS). H. sabdariffa showed high reducing capacity in FRAP assay and significant capability to scavenge peroxyl radicals in the ORAC assay. Nevertheless, the extract exhibited poor efficacy to inhibit peroxyl radicals in lipid systems. The plant extract also exhibited the capacity to decrease serum triglyceride concentration on hyperlipemic mouse model.     

Effects of Salvia officinalis and Thymus vulgaris on oxidant-induced DNA damage and antioxidant status in HepG2 cells

Salvia officinalis (SO) and Thymus vulgaris (TV) are medicinal plants well known for their curative powers. However, the molecular mechanisms responsible for these abilities of sage and thyme have not been fully understood yet. In this study we investigated the composition and the quantitative estimation of plant extracts, the protective effects of plant extracts against hydrogen peroxide- and 2,3-dimethoxy-1,4-naphthoquinone-induced DNA damage, and levels of enzymatic and non-enzymatic antioxidants (superoxide dismutase, glutathione peroxidase, glutathione) in human HepG2 cells. To measure antioxidative activity of plant extracts we used three assays: 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The results showed that the oxidant-induced DNA lesions were significantly reduced in cells pre-treated with the plant extracts studied. The observed DNA-protective activity could be explained by both elevation of GPx activity in cells pre-treated with SO and TV and antioxidant activity of SO and TV.     

Effect of processing on antinutrients and in vitro protein digestibility of kidney bean (Phaseolus vulgaris L.) varieties grown in East Africa

The effects of hydration, autoclaving, germination, cooking and their combinations, on the reduction/elimination of antinutrients, flatus-producing compounds and the improvement of in vitro protein digestibility of three selected Phaseolus vulgaris varieties were investigated. Reduction in the amount of total α-galactosides was attained by employing hydration process and was due to the differential solubility of the individual oligosaccharides and their diffusion rates. Due to their heat-sensitive nature, saponins, trypsin inhibitors and phytohaemagglutinins, diminished drastically to undetectable amounts when heating processes (cooking and autoclaving) were employed. Hydration and germination processes were less effective in reducing trypsin inhibitors, saponins and phytohaemagglutinins as compared with cooking/autoclaving processes. Germination process reduced stachyose, raffinose, phytic acid and tannins which was due to metabolic activity. The combination of germination followed by autoclaving processes yielded the most promising result in this study. The bean variety Roba exhibited better protein digestibility on processing and thus has high potential to be used as a raw material for the manufacturing of value-added products.     

Polyphenols and triterpenes from Chaenomeles fruits: Chemical analysis and antioxidant activities assessment

Mugua, fruit of the genus Chaenomeles, is a valuable source of health food and Chinese medicine. To elucidate the bioactive compounds of five wild Chaenomeles species, extracts from fresh fruits were investigated by HPLC-DAD/ESI-MS/MS. Among the 24 polyphenol compounds obtained, 20 were flavan-3-ols (including catechin, epicatechin and procyanidin oligomers). The mean polymerisation degree (mDP) of procyanidins was examined by two acid-catalysed cleavage reactions; the mDP value was the highest in Chaenomeles sinensis and the lowest in Chaenomeles japonica. Total polyphenol content (TPC) reached 46.92 and 46.28 mg/g gallic acid equivalents (GAE) in Chaenomeles speciosa and Chaenomeles thibetica, respectively, although their main bioactive compounds were different (being epicatechin and procyanidin B2 in the former, and catechin and procyanidin B1 in the latter). These two species also exhibited equally strong free radical scavenging activities. Our results further showed that the antioxidant ability of Chaenomeles fruits was significantly correlated to their total polyphenol contents. Two triterpenes (oleanolic acid and ursolic acid) were the highest quantity in Chaenomeles cathayensis and C. thibetica, respectively.     

Functional properties of three common bean (Phaseolus vulgaris) cultivars stored under accelerated conditions followed by extrusion

Flor de Mayo M38, Pinto Villa and Bayo Victoria beans were stored under accelerated conditions for aging at 40 °C and 60% RH for 3 months. Following adjustment of moisture to 24, 26 and 28 g water/100 g solids, they were extruded at 165, 185 and 205 °C at a constant screw speed. Water absorption index (WAI) and bulk density of extrudates were measured. Feed humidity did not affect the evaluated properties. Storage conditions, temperature and cultivar were the parameters that influenced the evaluated properties. Higher value for WAI was obtained in aged beans, independently of cultivar, temperature and feed humidity used. The bulk density was similar for aged and not aged beans, but at the highest temperature it was lower for aged beans. This fact indicates that bean storing and interaction of temperature have important influence on the final quality of extrudates.     

Determination of carotenoids in Dunaliella salina cultivated in Taiwan and antioxidant capacity of the algal carotenoid extract

A simple HPLC method with good separation efficiency was developed to determine all-trans and cis forms of carotenoids in Dunaliella salina cultivated in Taiwan. The analysis used a C30 column (250 × 4.6 mm, 5 μm) and an isocratic solvent system (flow rate = 1 mL/min) mixing methanol–acetonitrile–water (84/14/2, v/v/v) and methylene chloride, (75/25, v/v). Carotenoids were detected at 450 nm. Moreover, the antioxidant capacities of the algal carotenoid extract were also evaluated with Trolox equivalent antioxidant capacity (TEAC) assay, reducing power and 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) radical scavenging assay. Results showed that 7 carotenoids in the algal extract could be separated simultaneously within 30 min and the total amount of them was 290.77 mg/g algae. The contents of all-trans-β-carotene and 9- or 9′-cis-β-carotene, the major carotenoids in the algae, were 138.25 and 124.65 mg/g algae, respectively. The contents of all-trans-lutein, all-trans-zeaxanthin, 13- or 13′-cis-β-carotene, all-trans-α-carotene and 9- or 9′-cis-α-carotene were 6.55, 11.27, 4.95, 2.69, and 2.41 mg/g algae, respectively. The algal carotenoid extract had significantly higher antioxidant activity than all-trans forms of α-carotene, β-carotene, lutein and zeaxanthin in all antioxidant assays. The cis forms of carotenoids, especially 9- or 9′-cis-β-carotene, might play crucial roles for the antioxidant capacities of the algal extract.     

Heat-induced modifications in the functional and structural properties of vicilin-rich protein isolate from kidney (Phaseolus vulgaris L.) bean

Heat-induced changes in the physico-chemical (and/or functional) and structural properties of protein isolate from kidney beans (KPI) were characterised. The extent of protein denaturation, free sulphydryl contents, surface hydrophobicity, as well as structural characteristics of the proteins were evaluated. Analyses of size-exclusion chromatography combined with laser scattering showed that the heating at 95 °C led to transformation of 7S-form vicilin to its 11S-form, and even higher molar mass (MW) oligomers or polymers. Moderate heating (for 15–30 min) significantly improved protein solubility, emulsifying and foaming activities (at neutral pH), whilst extensive heating (for 60–120 min) on the contrary decreased these properties. Spectral analyses of fluorescence and/or Raman spectroscopy showed that tertiary and secondary conformations of protein in KPI were remarkably affected to a varying extent by the heating. The results suggested a close relationship between functional properties of the vicilin from kidney bean and its conformational characteristics.     

Physicochemical and structural characterization of Lima Bean (Phaseolus lunatus) globulins

A globulin fraction from Phaseolus lunatus have been isolated and characterized. The fractionation scheme used allowed to obtain a Globulin partially purificated. Globulin purification by ultracentrifugation allowed to isolate three peaks with different sedimentation coefficient, while gel filtration chromatography yielded two species, I and II, which were later identified as 11S and 7S globulins, respectively. Species II, 7S globulin from P. lunatus, seems to have a molecular mass of 72 kDa and to be constituted by polypeptides of 34-36, 25-27 and 16-18 kDa without intermolecular disulfide bonds. These polypeptides would present certain heterogeneity, as suggested by the results of isoelectric focusing and electrophoresis analyses. This protein exhibited some particular features, including a lower molecular mass and higher thermal stability than typical vicilins. Species I, with a molecular mass of 336 kDa, would be constituted by subunits of 53-55 and 40-41 kDa formed by smaller polypeptides (around 30 and 20 kDa) linked by disulfide bonds. These features, together with the existence of basic and acid polypeptides in the molecule, would confirm that species I is a globulin of the legumins, 11S globulins or α-conglutin family.     

Genetic and environmental effects on chemical composition related to sensory traits in common beans (Phaseolus vulgaris L.)

The chemical composition determines plant-derived foods’ sensory traits; genetic and environmental effects and their interactions determine chemical composition. Understanding the importance of each factor should help characterise foodstuffs according to the variety and place of cultivation. We studied the effects of variety (five landraces + two checks) and environment (five locations and two years) on some molecules important for beans’ (Phaseolus vulgaris L.) sensory value. The greatest location effects were on protein and starch content and variety effects were due to combinations of traits (mainly sucrose, protein, and malic acid). The variety × location interactions detected in protein, sucrose, citric acid, and malic acid were difficult to associate to the gastronomic success of a particular variety cultivated at a particular location. Our results showed that protected designation of origin (PDO) in beans could be delimited on the basis of chemical composition, derived from the particular environmental characteristics of a region and the genetic characteristics of the varieties admitted.     

Impact of industrial processing and storage on major polyphenols and the antioxidant capacity of tropical highland blackberry (Rubus adenotrichus)

Critical steps of a typical industrial line for processing a blackberry-based beverage in glass bottles have been studied, together with the effects of storage of final product at four different temperatures. For the steps, contents of total phenolics, anthocyanins, ellagitannins, and minor phenolic compounds were assessed by HPLC-DAD and antioxidant capacity by H-ORAC and DPPH. Thermal processes, especially blanching, drastically reduced anthocyanins, whereas hot-filling degraded ellagitannins. The final product showed reduced values for the anthocyanins cyanidin-3-glucoside (by 52%) and cyanidin-3-malonyl glucoside (64%), and ellagitannins lambertianin C (80%), and sanguiin H-6 (50%). Antioxidant capacity (H-ORAC) dropped by almost 47%. The anthocyanins and ellagitannins continued degrading during storage, especially if temperatures were high. Reduction kinetic parameters during storage were estimated for anthocyanins and, for the first time, for both lambertianin C and sanguiin H-6.     

Effect of pressure cooking on the antioxidant activity of extracts from three common bean (Phaseolus vulgaris L.) cultivars

Common bean is a traditional legume that is becoming more attractive because of its dietary and associated health benefits. Flor de Mayo M38, Pinto Villa and Bayo Victoria, three common bean cultivars developed in Mexico, were tested for phenol content and free radical scavenging activity before and after autoclaving. Independent analysis of seed coat and cotyledon was performed for each cultivar. Longer cooking times enhanced diffusion of phenols from seed coats to cooking water and from there to cotyledons. Cooking waters showed a remarkable activity similar to crude seed coats extracts although their phenol content was 80% lower.