Features and performance of edible films,obtained from whey protein isolate formulated with antimicrobial compounds

The goal of this research effort was to assess the efficacy of edible films produced from whey protein isolate (WPI) and glycerol, including incorporation of lactic acid (LA) and propionic acid (PRO), chitooligosaccharides with nominal MW of 3 kDa (COS) and natamycin (NA) as antimicrobial agents. Their features were evaluated in vitro via agar diffusion and viable cell counting, against spoilage microflora often found contaminating cheese surfaces. The effect of incorporating the aforementioned compounds upon thickness, moisture content (MC), solubility (S), density (ρ^s), water activity (a_w) and water vapor permeability (WVP), as well as upon tensile and optical properties of those films were also evaluated. Films formulated with LA, PRO or COS exhibited antimicrobial activity against all microorganisms tested, yet the viable cell count assay was more sensitive and reproducible. COS was the most active against Gram-negative bacteria, whereas LA was the most active against Gram-positive ones. NA was not active against bacteria, but displayed the strongest effect against yeasts. Incorporation of said antimicrobial compounds did not significantly (p > 0.05) affect film thickness, yet it significantly (p < 0.05) reduced tensile strength (TS). Incorporation of LA and NA in particular did not significantly (p < 0.05) affect MC, S, ρ^s, WVP, elongation at break (EB) and Young's modulus (YM) values; however, a statistically significant increase (p < 0.05) of MC, S and WVP, together with a statistically significant decrease (p < 0.05) of ρ^s were attained upon incorporation of PRO or COS. Moreover, PRO produced the highest variation (p < 0.05) in EB, TS and YM, whereas COS produced the highest change (p < 0.05) in optical properties.     

Heat-induced Maillard reaction of the tripeptide IPP and ribose: Structural characterization and implication on bioactivity

Maillard reaction products (MRPs) were prepared from aqueous model mixtures containing 60 g L^? 1 ribose and 30 g L^? 1 of the bioactive tripeptide IPP (Ile-Pro-Pro), heated at 98 °C. MRP and associated reactions with changes in IPP were observed within one hour of heat-treatment. The pH of MRPs decreased significantly during the heat treatment of IPP–ribose mixtures from 9.0 to 7.6 after one hour. The amino group content, IPP and ribose concentration decreased significantly during heat treatment. The fluorescence intensity of the IPP–ribose MRPs reached the maximum within 2 h. Modification of the UV/vis spectra for IPP–ribose MRPs was mainly due to a condensation reaction of IPP with ribose. Compounds with molecular weight between 300 and 650 Da were dominant while compounds smaller than 250 Da were also produced during the reactions, as characterized by size exclusion chromatography. Mass spectrometry revealed that IPP was conjugated to ribose at the N-terminal (m/z of 458.3) upon heat-treatment. The presence of ribose also promoted peptide degradation to dehydrated IP (m/z of 211.1). IPP–ribose MRPs lost the known angiotensin-I-converting enzyme (ACE) inhibitory activity of IPP; however, strong antioxidant properties were detected.     

Purification and identification of antioxidant peptides from corn gluten meal

Corn gluten meal was hydrolyzed by alkaline protease and Flavourzyme to obtain the antioxidant peptides. The antioxidant activities of the hydrolysates or peptides were evaluated by free radical scavenging capacity (1,1-diphenyl-2-picrylhydrazyl/2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt/hydroxyl radical/superoxide radical anion), metal ion (Fe²⁺/Cu²⁺) chelating activity and lipid peroxidation inhibitory capacity. The hydrolysates were separated by ultrafiltration, and those with molecular weight <10 kDa exhibited highest antioxidant activity in all relevant assays. The hydrolysates were subsequently purified by gel filtration chromatography, and fraction F3 showed the highest antioxidant activity. Three peptides were identified from fraction F3 using LC–ESI–Q–TOF MS/MS as Leu-Pro-Phe (375.46 Da), Leu-Leu-Pro-Phe (488.64 Da) and Phe-Leu-Pro-Phe (522.64 Da). These peptides exhibited good free radical scavenging activity and lipid peroxidation inhibitory effect. Thus, corn gluten meal may be used as a potential source of antioxidant peptides for food and nutraceutical applications.     

Release of multifunctional peptides by gastrointestinal digestion of sea cucumber (Isostichopus badionotus)

Sea cucumber is a benthic marine organism distributed worldwide and used as food in several Asian countries. The species Isostichopus badionotus is captured intensively off the Yucatan Peninsula, Mexico. Boiled I. badionotus was subjected to in vitro simulated gastrointestinal digestion using pepsin and a pepsin–Corolase PP^® mixture. ACE-inhibitory and radical scavenging activities, iron reducing capacity and cytotoxic effects against colorectal cancer cells were evaluated in the hydrolysates and their ultrafiltered fractions. ACE-inhibitory activity was potent in fractions containing peptides <3000 Da, an effect augmented with combined action of gastric (pepsin) and intestinal (Corolase PP^®) enzymes (IC₅₀ = 0.038 ± 0.004 mg/mL). Antioxidant activity was exerted by peptides with low and high molecular weights, depending on hydrolysis method. This is the first report of cytotoxic capacity against colorectal HT-29 cells in peptides from sea cucumber. Sea cucumber hydrolysates and ultrafiltered fractions are potential ingredients for development of functional foods.     

Phytosterols and tocopherols content of pulps and nuts of Brazilian fruits

Fruits and nuts from the North and Northeast regions of Brazil were collected to determine their phytosterol and tocopherol content. The species studied were Cotia nut (Aptandra spruceana M.), Brazil nut (Bertholletia excelsa H.B.K.), Mucajá (Couma rigida M.), Red Açaí (Euterpe oleracea M.), Inajá (Maximiliana maripa D.), Jenipapo (Genipa Americana L.), Buriti (Mauritia flexuosa L.) and Uxi (Endopleura uchi C.). Phytosterols were analyzed by GC–FID using β-cholestanol as an internal standard, while tocopherols were determined by RP-HPLC-DAD. The pulps of Mucajá (26–236 mg 100 g^–1), Inajá (119–285 mg 100 g^–1) and Jenipapo (216 mg 100 g^–1) showed the highest total phytosterol contents. Considering α-tocopherol equivalents, the pulps of Buriti (346.72 μg g^–1) and Uxi (200.92 μg g^–1) contained the highest vitamin E activity. Therefore, the results indicate that these fruits and nuts have great potential to be cultivated and marketed as alternative dietary sources for these bioactive compounds.     

Decontamination of Salmonella enterica Typhimurium on green onions using a new formula of sanitizer washing and pulsed UV light (PL)

Pathogenic bacteria such as Salmonella and Shigella flexneri have been linked to green onion contamination. This study was conducted to evaluate decontamination of Salmonella Typhimurium using a new formula of sanitizer washing (0.4 mg/mL thymol and five new formula sanitizers including 300 ppm H₂O₂ + 4% SDS, 2 mg/mL citric acid + 4% SDS, 0.2 mg/mL thymol + 4% SDS, 0.2 mg/mL thymol + 2 mg/mL citric acid and 0.2 mg/mL thymol + 2 mg/mL acetic acid), pulsed UV light (PL) as well as synergy between the sanitizer wash and PL. New formula sanitizers based on decontamination efficacy of single washing solutions (organic acids, hydrogen peroxide (H₂O₂), essential oil or surfactant) were applied to decontaminate spot inoculated green onions. PL, the novel technique, alone has been applied to inactivate Salmonella on both dip and spot inoculated green onions. Salmonella inactivation of PL–new formula sanitizer combinations on dip inoculated green onions was investigated for their potential synergy. As a result, for spot inoculated green onions, 0.4 mg/mL thymol individually and the five new formula sanitizers all achieved higher log reduction of Salmonella (4.5–5.3 log 10 CFU/g reduction) than the 200 ppm chlorine washing. These new formulas of sanitizer would be potential alternatives to chlorine. The 5 s dry PL (4.6 log 10 CFU/g) or 60 s wet PL treatment (3.6 log 10 CFU/g) was better or comparable as chlorine washing. The sanitizer combinations did not provide significantly higher log reduction than PL, and PL has the potential of being used in the green onion industry for decontamination purpose. For dip inoculated green onions, none of our treatment provided > 0.8 log 10 CFU/g (0.6–0.8 log 10 CFU/g) reduction of Salmonella. As a result, the PL–new formula sanitizer combinations had no or minimal synergy to inactivate Salmonella dip inoculated on green onions.     

Antiangiogenic properties of carotenoids: A potential role of maize as functional food

Several human disorders are associated with neovascularization. The current in vivo study examines the effect in the blood vessel formation of a xanthophyll-rich seed extract of maize. The angiostatic effects of treatment with maize seed carotenoid extract (0.1–10 μM of zeaxanthin equivalent/implant) were evaluated in the chick yolk sac membrane (YSM) (12–50% inhibition, P < 0.05) as well as in the chorioallantoic membrane (CAM) assay (23–52% inhibition, P < 0.05) as compared to control group. A similar inhibitory action was found by treatments with the retinoic acid (10 μM/embryo, 49% and 57% inhibition) and commercial lutein (10 μM/embryo, 65% and 55% inhibition) (positive controls) performed in the YSM and CAM, respectively. Results point to maize seeds as interesting sources of xanthophylls which effectively inhibited the process of vessel formation, suggesting a potential role of such compounds in the prevention of diseases associated with vascular dysfunction.     

Thermodynamic analysis of the sorption isotherms of pure and blended carbohydrate polymers

The adsorption isotherms of gum Arabic (GA), mesquite gum (MG), and maltodextrin DE 10 (MD), and a blend of the three gums (17%GA–66%MG–17%MD) were determined at 25, 35, and 40 °C. All isotherms were fitted using the GAB model and the thermodynamic properties (enthalpies and entropies, differential and integral) were estimated by the Clausius–Clapeyron method. The minimum integral entropy was considered as the point of maximum stability where strong bonds between the adsorbate and adsorbent occurred, and water is less available and likely to participate in spoilage reactions. The point of maximum stability was found between 12.24 and 14.68 kg H₂O/100 kg d.s. (corresponding to water activity, a_w, of 0.32–0.57) for GA, 12.12–14.27 kg H₂O/100 kg d.s. (a_w = 0.33–0.55) for MG, and 11.37–13.84 kg H₂O/100 kg d.s. (a_w = 0.28–0.55) for the biopolymer blend, in the temperature range studied.     

Citharexylum solanaceum fruit extracts: Profiles of phenolic compounds and carotenoids and their relation with ROS and RNS scavenging capacities

Citharexylum solanaceum is a native fruit from Brazil, which both bioactive compounds and antioxidant potential were not yet investigated. Thus, the freeze-dried extracts of seed and pulp + skin of C. solanaceum fruits were obtained after solid-liquid extraction with ethanol and their bioactive compounds composition, namely phenolic compounds and carotenoids, were determined. The antioxidant capacity of both extracts against physiologically relevant reactive oxygen species (ROS) and reactive nitrogen species (RNS) was further investigated. Both C. solanaceum extracts showed high contents of phenolic compounds; however, pulp + skin extract presented 2.4-times more phenolic compounds (33.54 mg/g) than the seed extract (14.09 mg/g). Verbascoside (phenylpropanoid) was the major compound identified in both extracts (11–25 mg/g). Regarding the carotenoid composition, all-trans-lutein (14–42 μg/g) and all-trans-β-carotene (13–44 μg/g) were the major compounds in both extracts. The high content of phenolic compounds and carotenoids in pulp + skin extract might explain its higher scavenging capacity against all the ROS/RNS as compared to seed extract. In general, both extracts showed better scavenging capacity for the RNS than for the ROS. Our results indicate that C. solanaceum fruits can be explored as an important natural source of antioxidant compounds.     

Routine and sensitive SPE-HPLC method for quantitative determination of pheophytin a and pyropheophytin a in olive oils

A sensitive and specific HPLC method with tandem diode array-fluorescence detection (DAD-FL) has been developed and validated for the simultaneous determination of pheophytin a (phy a) and pyropheophytin a (pyrophy a) in olive oils. Pigments were extracted with reverse phase solid phase extraction (RP-SPE) and subsequently analysed by HPLC-DAD-FL. The chromatographic analysis was carried out isocratically on ODS2 RP column using methanol–acetone (1:1 v/v) at flow-rate of 2.0 ml min⁻¹. Specificity of the method was assured by the simultaneous detection by UV–visible (410 nm) and FL (λ_Ex: 410 nm; λ_Em: 672 nm). Both compounds could be baseline separated within 7 min. The method was validated and applied in olive oil samples recently extracted as well as stored during 12 months. The limit of detection (LOD) defined at a signal-to-noise ratio of about 3 was ∼21.6 ng g⁻¹ for pyrophy a and ∼24.6 ng g⁻¹ for phy a under FL detection, and ∼148.0 ng g⁻¹ for both analytes under UV–visible detection. The calibration graphs were linear (r² > 0.9999; p < 0.01) between 0.25–14.00 ng μl⁻¹ for pyrophy a and 0.25–19.00 ng μl⁻¹ for phy a, under both fluorescence and UV–visible detection conditions. Recoveries of phy a and pyrophy a were over 94% as estimated by the standard addition method. Relative standard deviation for the intra-day and inter-day determination of phy a and pyrophy a were lower than 3.7% and 8.0%, respectively.     

Modeling the inactivation kinetics of fruit bromelain in pineapple during high-pressure and thermal treatments

The stability of fruit bromelain (FBM) in pineapple pulp was studied within a high-pressure domain of 0.1–600 MPa/30–70 °C/1 s–30 min. The pulse effect was quantified as a function of pressure, temperature, pressure build-up and decompression times. A maximum of 60% reduction in FBM activity was obtained after a single pulse of 600 MPa/70 °C. Upon applying nth order model, the obtained reaction order (n) for thermal (0.1 MPa/30–70 °C) and high-pressure (100–600 MPa/30–70 °C) inactivation was 1.1 and 1.2, respectively. The inactivation rate constant (k) ranged from 1.2 to 45.0 × 10^− 3 U^n − 1 min^− 1. The activation energy was nonlinearly dependent on pressure (P); whereas, the activation volume was linearly related to temperature (T). The nonlinear dependence of k on P and T was modeled by an empirical equation. The D-values obtained from the empirical model appeared to be more realistic than those from the log-linear kinetics.Industrial relevancePineapple fruit bromelain (FBM) has numerous health benefits and therapeutic effects. It is a protease enzyme that helps in digestion. Processing of pineapple pulp needs attention towards retaining the maximum FBM activity in it. A detailed kinetic study of FBM within a broad range of pressure–temperature–time domain will help in designing a high-pressure process for the pineapple pulp with respect to its bromelain stability.     

Antioxidant activity of protein hydrolysates and purified peptides from Zizyphus jujuba fruits

In recent years, there has been a considerable interest in bioactive peptides derived from food proteins which might have beneficial effects on human health. Zizyphus jujuba is a medicinal plant with well-demonstrated biological functions for which various bioactive compounds except antioxidant peptides have been reported. Therefore, the aim of this study was to determine the antioxidant activity of Z. jujuba-derived protein hydrolysates and the purified peptides. Based upon this study, it was revealed that the hydrolysates prepared from Z. jujuba fruit possessed antioxidant effects. Among the prepared hydrolysates, trypsin hydrolysate with the highest antioxidant activity was fractionated using reverse-phase high-performance liquid chromatography (RP-HPLC). The most potent antioxidant peptides, named fractions F3 and F6, identified as VGQHTR (MW: 678.36 ± 0.3 Da) and GWLK (MW: 482.27 ± 0.3 Da), respectively, using tandem mass spectrometry. This study demonstrated that the derived hydrolysates and the purified peptides from Z. jujuba proteins can prevent oxidative reactions and might be underutilised for food preservation and medicinal purposes. However, more detailed studies are required to explore their antioxidant abilities in vivo.     

Depuration of cadmium from blue mussel (Mytilus edulis) by hydrolysis peptides and chelating metal elements

The present experiment was conducted to investigate the effects of prepared hairtail (Lepidopusc audatus) hydrolysis peptide–metal element (Fe^2 +, Zn^2 +, Ca^2 +, or Mg^2 +) complexes (PH–Fe^2 +, PH–Zn^2 +, PH–Ca^2 +, or PH–Mg^2 +) on the depuration of cadmium (Cd) from blue mussel (Mytilus edulis) tissues. Cd concentrations in anterior adductor muscle, posterior adductor muscle, gill, mantle, and visceral mass of mussels were 11.391, 15.323, 63.672, 19.509, and 109.621 μg/g, respectively, after 5 days of exposure to 0.32 mg/L Cd. Five groups of these exposed mussels were then exposed to seawater laced with four different concentrations of the peptide complexes listed above (5, 10, 15, and 20 mg/L) for 8 days. After 8 days of depuration, 5 mg/L of PH–Fe^2 +, PH–Zn^2 +, and PH–Ca^2 + showed no significant (P > 0.05) effects on Cd concentrations in mussel tissues. However, significant differences (P < 0.05) were observed in groups exposed to 20 mg/L of PH–Fe^2 +, PH–Zn^2 +, and PH–Ca^2 +. The Cd concentrations in anterior adductor muscle, posterior adductor muscle, gill, mantle, and visceral mass were significantly (P < 0.05) decreased by 29.56–35.83%, 27.51–33.62%, 31.59–40.34%, 25.83–31.28%, and 33.62–33.97%, respectively. Nevertheless, the variables of Cd concentrations in tissues treated with 5–20 mg/L PH–Mg^2 + showed no significant (P > 0.05) differences from controls at any point during the experimental period. For these reasons, PH–Fe^2 +, PH–Zn^2 +, and PH–Ca^2 + can be recommended as depuration agents in mussel feed to decrease the Cd concentrations in tissues.     

Comparison of subjective grading and objective assessment in meibography

AimTo analyse repeatability of subjective grading and objective assessment in non-contact infra-red meibography.MethodsMeibography photographs of 24 subjects (female 14; mean age = 46; range = 19–69 years, upper-lid images = 12, lower-lid images = 12) were classified in two sessions by three experienced observers (OI, OII, OIII). Relative area or portion affected by meibomian glands (MG) loss was classified applying three different grading scales in randomized order: a four-grade scale (4S) (degree 0 = no partial glands; 1 = <25% partial glands; 3 = 25–75% partial glands; 3 = >75% partial glands), a pictorial five-grade scale (5S) (degree 0 = no meibomian gland loss (MGL); 1 = <25% MGL; 3 = 26–50% MGL; 3 = 51–75%; 4 = >75% MGL) and objectively by a 100-grade scale (DA) applying ImageJ software.ResultsObserved MG loss ranged from 0% to 69%. Intra-observer agreement of the 5S (OI: κ = 0.80, p < 0.001; OII: κ = 0.40, p = 0.009; OIII κ = 0.81, p < 0.001) was better than of the 4S (OI: κ = 0.79, p < 0.001; OII: κ = 0.15, p = 0.342; OIII κ = 0.50, p = 0.0071). Intra-observer agreement of OI and OIII (±0.88 (95% confidence interval), ±1.305) was better than of OII (±2.21) in 4S and 5S (±0.99, ±2.00 and ±0.91; OI, OII and OIII, respectively) while it was relatively similar in DA (±18, ±17 and ±17). Inter-observer agreement was better in DA (OI–OII: ±13, OI–OII: ±19, OII–OIII: ±26) than in 4S (OI–OII: ±1.76; OI–OIII: ±1.29 and OII–OIII: ±1.31) or 5S (OI–OII: ±1.49; OI–OIII: ±0.91 and OII–OIII: ±1.20).ConclusionIntra-observer and inter-observer agreement was better in computerized grading followed by the subjective five-grade scale and four-grade scale.     

Growth-inhibition of hiochi bacteria in namazake (raw sake) by bacteriocins from lactic acid bacteria

The bacteriocins produced by Lactococcus lactis subsp. lactis C101910 (C101910) and NBRC 12007 (NBRC 12007) were used to prevent the growth of sake spoiling hiochi bacteria (Lactobacillus hilgardii, Lactobacillus fructivorans, and Lactobacillus paracasei) in namazake, which is raw (unpasteurized) sake. The bacteriocin concentrations required for decreasing the viable cell concentrations of L. hilgardii and L. fructivorans below the detection limit (1.0 × 10² cells/ml) in 24 h from the initial concentration of 4.0–9.5 × 10⁵ cells/ml in the namazake at pH 4.5 and at 4°C, were 18–35 U/ml and 5.6 U/ml for the bacteriocin from C101910 and NBRC 12007, respectively. To decrease the viable cell concentration of L. paracasei from the initial concentration of 7.5 × 10⁵ cells/ml to below the detection limit (1.0 × 10² cells/ml) in 24 h, 350 U/ml bacteriocin from C101910 and 140 U/ml bacteriocin from NBRC 12007 were required. In experiments using McIlvaine buffer (pH 4.5) with 15% ethanol instead of namazake as the medium, the viable cell concentrations of L. hilgardii and L. paracasei decreased to less than 1.0 × 10² cells/ml, whereas those of L. fructivorans decreased to less than 1.0 × 10³ cells/ml, when bacteriocins were added at the concentrations that had proven effective in namazake. The membrane depolarization assay using a fluorescent probe showed that the presence of ethanol stimulated the collapse of the membrane potential induced by bacteriocins. The ethanol induced collapse of the membrane potential suggests that the application of bacteriocins at the storage stage of namazake is more beneficial than when used in other stages of the sake brewing process.     

Modeling the effect of natamycin,pine-resin and environmental factors on the growth and OTA production by Aspergillus carbonarius using response surface methodology

The effect of two antifungal compounds (natamycin, pine-resin), temperature and water activity, on the growth rate, lag phase duration and Ochratoxin A (OTA) production by three Aspergillus carbonarius isolates (Ac-28, Ac-29, and Ac-33), was studied by means of Response Surface Methodology (RSM) based on a Central Composite Design (CCD). Two different experimental designs were performed as a function of temperature (16.6–33.4 °C), water activity (0.90–0.97 a_w), natamycin (0–1000 ng ml^− 1) or pine-resin (0–2.61%, w/v) on a Synthetic Grape-juice Medium (SGM). OTA production was analyzed after 5, 10 and 15 days of incubation. A second-order polynomial model was fitted to each response parameter to assess the growth and OTA potential of all fungal isolates. Results showed that natamycin, a_w and temperature had significant effects on the lag phase duration of all isolates, as well as on OTA accumulation after 10 days of incubation for Ac-29 and 15 days for Ac-28 and Ac-33 isolates. The same results were obtained for OTA production after treatment with pine-resin. However, fungal growth rates were not statistically significant in both experiments, with the exception of Ac-29 and Ac-33 after treatment with pine-resin. Overall, high natamycin concentrations (800 and 1000 ng ml^− 1) delayed fungal growth depending on the environmental factors assayed. Moreover, treatment with pine-resin at 16.6 °C/0.94 a_w/1.1% w/v, as well as at 25 °C/0.90 a_w/1.1% w/v, completely inhibited fungal growth up to 15 days of incubation.     

Moisture sorption isotherms of high pressure treated fruit peels used as dietary fiber sources

High hydrostatic pressure (HHP) treatments can improve the potential of orange, mango, and prickly pear peels as food formulation fiber sources. Akaike Information Criteria differences identified Peleg and GAB as the best model alternatives to describe experimental moisture isotherms. HHP (600 MPa/10 min/22 and 55 °C) effects on moisture isotherms expressed as relative water sorption content change with respect to controls (RWSC_aw) showed that in the 0.1–0.93 a_w range, HHP improved the adsorption water retention of orange peels. The same was true for the desorption water retention for all HHP-treated fruit peels except for prickly pear HHP-treated at 22 °C and > 0.35 a_w. The area under the hysteresis curve (A_H) in the 0.15–0.51 a_w range showed that HHP increased hysteresis for all fruit peels tested. All this illustrates the HHP potential to modify the hygroscopic properties of fruit peels at lower temperature and in less processing time than conventional processes.Industrial relevanceOrange, mango, and prickly pear peels are potential food fiber formulation sources with differentiated hygroscopic and functional properties. In this study, 600 MPa treatments at 22 and 55 °C for 10 min modified the adsorption and desorption moisture retention capacity of all fruit peels tested in this study. HHP technology can improve the potential of fruit peels as dietary fiber sources with the advantage of shorter processing times and lower temperatures than conventional technologies used to treat food fibers.     

Nondestructive estimation of fatty acid composition in soybean [Glycine max (L.) Merrill] seeds using Near-Infrared Transmittance Spectroscopy

The potential of Near-Infrared Transmittance (NIT) Spectroscopy for estimation of fatty acid composition in soybean seed samples was studied. Total 612 whole seed samples with wide range of variability for major fatty acids were used to develop calibration equations by applying SNV de-trend and first derivative mathematical treatment in the range of 850–1048 nm. Useful chemometric models for most important fatty acids present in soybean seed oil were developed using Modified Partial Least Squares (MPLS) regression method. In external validation oleic (r² = 0.89, SEP = 1.61), linoleic (r² = 0.86, SEP = 1.50) and palmitic (r² = 0.89, SEP = 0.17) acids were predicted with good accuracy, while the predictions for linolenic acid (r² = 0.78, SEP = 0.36) and stearic acid (r² = 0.63, SEP = 0.11) had relatively poor accuracy. The whole-seed NIT spectroscopy equations for fatty acid estimation would be useful for improving efficiency of breeding programs aimed at altering fatty acid composition in soybean.     

Analysis of nutrient and antinutrient content of underutilized green leafy vegetables

Analysis of chemical composition of 13 locally available underutilized green leafy vegetables (GLV) was the objective of this study. Moisture, ash and ether extract of the greens were in the range of 73–95 g/100 g, 0.77–3.54 g/100 g and 0.2–0.9 g/100 g, respectively. Four GLV had high iron content (13.15–17.72 mg/100 g) while the rest had lower levels (2.62–9.86 mg/100 g). Calcium content varied largely between the greens ranging from 41 mg/100 g in Polygala erioptera to 506 mg/100 g in Digera arvensis, whereas phosphorous ranged from 16 to 63 mg/100 g. Ascorbic acid was higher in Delonix elata (295 mg/100 g) and Polygala erioptera (85 mg/100 g) and lower in others (3–46 mg/100 g). Thiamine was found to be less than 0.1 mg/100 g in six greens and 0.1–0.33 mg/100 g in others. Total carotene content ranged between 10 and 35 mg/100 g in all with exceptionally high amount in Cocculus hirsutus (67 mg/100 g) and Delonix elata (60 mg/100 g). $\beta$-carotene was 13–25% of total carotene in all greens. Oxalate content was below 100 mg/100 g in five greens and less than 1400 mg/100 g in the remaining GLV. Tannin content ranged between 61 and 205 mg/100 g in all GLV with the exception of Coleus aromaticus (15 mg/100 g) and Delonix elata (1330 mg/100 g).     

Salmonella contamination of laying-hen flocks in two regions of Algeria

A preliminary epidemiological study of Salmonella contamination in laying-hen flocks was carried out in the regions of Annaba and Eltarf, Algeria, from March to October 2008 and March to November 2009. Our objectives were (i) to estimate the prevalence of infection by Salmonella spp. in seven pooled samples during the hens' laying period (ii) to identify the serotypes and antimicrobial resistance phenotypes of isolates, and (iii) to characterize the factors that may be related to Salmonella contamination in Algerian henhouses. For this purpose, 18 out of 22 operational laying-hen houses were sampled one to three times during these periods: once at the start of laying (pullets aged 22–31 weeks), once in the middle of laying (47–60 week) and once at the end of laying prior to depopulation (70–86 week). The flocks'Salmonella status was assessed by collecting 2754 environmental samples that were analyzed according to the ISO 6579 method. The antibiotic resistance of Salmonella strains was tested as per the guidelines of the Clinical and Laboratory Standards Institute (CLSI). The relationship between each potential risk factor and the Salmonella status of laying-hen flocks was evaluated by calculating the relative risk with 95% confidence intervals. Eight flocks tested positive for Salmonella spp., with a higher prevalence at the end of laying than at either the beginning or middle. Only 19 isolates were recovered from the 2754 samples analyzed and nine different serotypes identified. S. enteritidis (n = 4) was the most prevalent serovar, along with S. Kentucky and S. Hadar (n = 3), followed by S. Heidelberg, S. Manhattan and S. Virchow (n = 2), whereas S. Dublin, S. Typhimurium and S. Albany were found only once. Thirteen isolates were resistant to at least one antimicrobial agent. Of these, six were resistant to at least three different antimicrobial classes. Salmonella serovar Kentucky isolates were resistant to fluoroquinolones with ciprofloxacin MIC ≥ 8 mg/L. Six risk indicators were identified as potentially related to the Salmonella status of layer houses.