Distribution of metals and phenolic compounds as a criterion to evaluate variety of berries and related jams

Polyphenols, anthocyanins, phosphate, iron, zinc, manganese, calcium, potassium, magnesium and sodium were evaluated both in berries belonging to the genera Rubus and Ribes and in related jams by means of spectrophotometric techniques, to verify a possible differentiation on the basis of these parameters. The phenolic and anthocyanins higher contents were detected for black currant fruits and jams. Regarding the total phenolic content, in 11 cases it is possible to observe a higher content in jams with respect to the related row fruits. All samples contain a high amount of potassium, calcium and magnesium but small quantities of sodium. Phosphate is abundant especially in currants. As regard jams all results about metals are lower than those obtained for fruits, this is due to the dilution during the preparation of the jams. Multivariate statistical analysis shows that on the basis of obtained analytical results it is possible differentiate not only fruit but also the derived jams.     

Survival and reproduction of Tribolium castaneum (Herbst), Rhyzopertha dominica (F.) and Sitophilus oryzae (L.) following periods of starvation

This study determined the starvation tolerance of Tribolium castaneum (Herbst), Rhyzopertha dominica (F.) and Sitophilus oryzae (L.) in terms of both adult survival and reproduction, the impact of starvation on reproduction not having been studied before. Experiments were conducted at 30 °C and 55% or 70% r.h. using a laboratory strain and a field strain of each species. The number of progeny was a better indicator of the impact of starvation on a species than adult survival. Tribolium castaneum was the most tolerant species, requiring up to 35 d starvation before no progeny were produced. Rhyzopertha dominica and S. oryzae required up to 8 d starvation before no progeny were produced. The results suggest that hygiene will have a greater impact on populations of S. oryzae and R. dominica than T. castaneum.     

Combating Mineral Malnutrition through Iron and Zinc Biofortification of Cereals

Iron and zinc are 2 important nutrients in the human diet. Their deficiencies in humans lead to a variety of health‐related problems. Iron and zinc biofortification of cereals is considered a cost‐effective solution to overcome the malnutrition of these minerals. Biofortification aims at either increasing accumulation of these minerals in edible parts, endosperm, or to increase their bioavailability. Iron and zinc fertilization management positively influence their accumulation in cereal grains. Regarding genetic strategies, quantitative genetic studies show the existence of ample variation for iron and zinc accumulation as well as inhibitors or promoters of their bioavailability in cereal grains. However, the genes underlying this variation have rarely been identified and never used in breeding programs. Genetically modified cereals developed by modulation of genes involved in iron and zinc homeostasis, or genes influencing bioavailability, have shown promising results. However, iron and zinc concentration were quantified in the whole grains during most of the studies, whereas a significant proportion of them is lost during milling. This makes it difficult to realistically assess the effectiveness of the different strategies. Moreover, modifications in the accumulation of toxic elements, like cadmium and arsenic, that are of concern for food safety are rarely determined. Trials in living organisms with iron‐ and zinc‐biofortified cereals also remain to be undertaken. This review focuses on the common challenges and their possible solutions related to agronomic as well as genetic iron and zinc biofortification of cereals.     

Iron corrosion activity of anaerobic hydrogen-consuming microorganisms isolated from oil facilities

The purpose of the present study was to test the hypothesis that anaerobic hydrogen-consuming microorganisms generally promote iron corrosion. We isolated 26 hydrogen-consuming microorganisms (acetogens, sulfate-reducing bacteria, and methanogens) from oil facilities in Japan using hydrogen as an electron donor. The iron corrosion activities of these microorganisms were examined using iron (Fe⁰) granules as the sole electron donor. Almost all the isolates consumed hydrogen that was chemically generated from iron granules but did not induce significant iron corrosion. The amount of corroded iron in the cultures of these organisms was less than 2-fold that in an abiotic chemical corrosion reaction. These results indicated that hydrogen consumption did not strongly stimulate iron corrosion. On the other hand, one isolate, namely, Methanococcus maripaludis Mic1c10, considerably corroded iron: this phenomenon was not accompanied by hydrogen consumption, methane formation, or cell growth. This finding also provided strong evidence that M. maripaludis Mic1c10 produced some material that caused iron to corrode.     

The dissolution rate of zinc pyrithione

A method of measuring and correlating the rate at which zinc pyrithione dissolves during a shampoo is described. The rise in zinc concentration of a solution in a stirred vessel following the introduction of a dose of zine pyrithione suspension was measured as a function of time using atomic absorption spectrophotometry. An analysis of the mass transfer processes occurring during the dissolution of a suspended solid in a stirred vessel was used to correlate the concentration-time measurements. The analysis allows a calculation of the characteristic solution time, the mass transfer coefficient and the diffusion coefficient for the system. In this way the effect of changing shampoo formulation can be systematically studied.
Le taux de dissolution de zinc pyrithione.     

The antidandruff efficacy of a shampoo containing piroctone olamine and salicylic acid in comparison to that of a zinc pyrithione shampoo

Dandruff (pityriasis capitis) is a chronic scalp condition characterized by scaling and sometimes itching and redness. Shampoos containing antifungal agents are used to control the scaling condition. In the present study, two shampoos with different actives are compared in a double-blind, randomised and bilateral study on 19 subjects. One shampoo contained piroctone olamine (0.75%) combined with salicylic acid (2%) and the other contained zinc pyrithione (1%) as active ingredient. The subjects were treated twice weekly with the shampoos for almost 4 weeks. Before each treatment the degree of dandruff was evaluated. Both shampoos were highly effective in reducing the dandruff. The combination of piroctone olamine and salicylic acid appeared to be slightly more effective than zinc pyrithione in reducing the severity and area affected by the scaling.     

Effects of starvation period on the locomotory response of Rhyzopertha dominica (F.)

In the context of developing a behavioural bioassay, the effects of 1-5 days starvation on the locomotory responses of Rhyzopertha dominica were investigated. Movements in an experimental arena with airflow were videoed and analysed using computerised tracking and motion analysis software. Beetle velocity and angular velocity (turning) were influenced adversely following 3 or 4 days of starvation, resulting in a lower number of beetles arriving at food. The highest number of beetles arriving at food was when they were starved for 1 day. Gender had a statistically significant effect on velocity; on average males walked 37% faster than females and there were significant decreases in the velocity of females from the fourth day and male velocity from the fifth day of starvation. Starvation significantly reduced angular velocity of beetles although the effect of gender was not statistically significant. There was a decline in angular velocity following the first day of starvation, although the negative effect of starvation on turning is not as clear-cut as on velocity, with a more gradual decline with increasing starvation. For undertaking behavioural bioassays with R. dominica, starvation beyond 1 day is unlikely to improve responsiveness.     

Malting revisited: Germination of barley (Hordeum vulgare L.) is inhibited by both oxygen deficiency and high carbon dioxide concentrations

During malting, barley (Hordeum vulgare L.) seeds are germinated to promote the mobilisation of storage compounds. Germination is strongly influenced by O₂ and CO₂; however, any distinction between the particular effects is missing. Since, in this study, the ambient O₂ concentration was maintained when high CO₂ concentrations were applied, for the first time the impacts of CO₂ and of O₂ deficiency could be distinguished unambiguously.Germination was inhibited by both O₂ deficiency and high CO₂ (80%) concentrations, documented by the lack of any growth of coleoptiles and any increase of α-amylase and β-glucanase activity. In contrast, the related impacts of O₂ starvation and high CO₂ on fermentation differ strongly, demonstrated by quite different patterns of ethanol emission. Additionally, the stress metabolism - monitored by the means of GABA accumulation - was also differently impacted. The elucidation of the underlying, so far unknown, mechanisms will provide novel opportunities to improve malting.     

Nutritional changes in the essential trace elements content of asparagus during industrial processing

Changes in the essential trace elements (copper, iron, manganese and zinc) of the asparagus (Asparagus officinalis, L.) were determined in order to investigate the effect of the industrial processing of asparagus on mineral content and estimate if these possible changes involve a modification of its nutritional value. The main effect was a decrease of iron and manganese levels and an increase in copper and zinc content throughout the processing. These modifications are especially related to the peeling of the asparagus since the loss of the spear peel may imply changes in the mineral content. Variations in the essential trace elements concentrations between portions are related to the way of peeling that hardly affects the tip portion. The largest thickness spears showed the highest mineral concentrations and were less influenced by processing. The results of the nutrient density confirm that asparagus is an adequate food source of mineral nutrients and that its processing has no consequences for its mineral nutritional value, especially the apical portion because of the mineral RDAs and ESADIs supplied.     

Effects of acetic acid and its assimilation in fed-batch cultures of recombinant Escherichia coli containing human-like collagen cDNA

The primary processing problem in recombinant Escherichia coli fermentation is the production of acetic acid, which can inhibit both cell growth and recombinant protein production. The ability of E. coli to assimilate acetate permits it to solve this problem in a rather creative manner. In this study, the effects of acetic acid assimilation through a glucose starvation period at different cell growth phases were investigated in fed-batch cultures of recombinant E. coli. Experimental results showed that the human-like collagen (HLC) production could be improved by introducing glucose starvation at the end of batch culture and pre-induction phase, while the glucose starvation at the induction phase resulted in a poor HLC productivity. The acetic acid assimilation was observed during all the glucose starvation periods. In addition, a systematic study for evaluating the effects of acetic acid was carried out by adding acetate into culture media at different cell growth phases and then employing a glucose starvation after several hours. It was found that obvious acetate inhibition on cell growth occurred in the batch culture phases while its inhibitory effect on HLC expression occurred only in the post-induction phase. The longer the elevated acetic acid concentration maintained, the stronger the inhibitory effects were. These results are of significance for optimizing and scaling-up fermentation processes.     

Effect of phytate reduction of sorghum,through genetic modification,on iron and zinc availability as assessed by an in vitro dialysability bioaccessibility assay,Caco-2 cell uptake assay,and suckling rat pup absorption model

Improved iron and zinc availability from sorghum, a commonly consumed staple, will benefit many malnourished communities in rural Africa burdened with high prevalence of iron and zinc deficiency. This research compared the effect of genetic phytate reduction in sorghum on iron and zinc bioaccessibility and uptake measured by in vitro dialysability and Caco-2 cell uptake assays to that of iron and zinc absorption measured by a suckling rat pup model. The phytate reduction (80–86%) in these sorghums significantly increased zinc availability. The Caco-2 cell method, but not the dialysability assay, proved useful in estimating zinc absorption. The measured increase in iron availability differed between the methods, possibly due to the effect of varying mineral (Ca, Fe, Zn, P) contents of the sorghums. This effect was most prominent in the iron uptake results. More research is needed to determine the effect of naturally occurring variations in mineral contents of sorghum on the iron uptake by Caco-2 cells.     

Effects of the addition of wild legumes (Lathyrus annuus and Lathyrus clymenum) on the physical and nutritional properties of extruded products based on whole corn and brown rice

The effects of the addition of wild legumes (Lathyrus) from the South of Spain on the physical and nutritional properties of extruded products based on whole corn and brown rice were studied. Samples were obtained with a Brabender single screw extruder. The physical characterisation of the expanded products was performed by the measurement of density, expansion, solubility and specific mechanical energy consumption (SMEC). Chemical composition, amino acids content, protein digestibility, total polyphenol content and potential availability of iron and zinc were determined.     

Bifidobacterium bifidum BF-1 suppresses Helicobacter pylori-induced genes in human epithelial cells

Helicobacter pylori infection alters gene expression in host cells. Specifically, inflammatory chemokines such as IL-8 are upregulated in the gastric mucosa during H. pylori infection. Although the mechanism by which H. pylori causes inflammation of the gastric mucosa is not yet understood, many studies have suggested that nuclear factor kappa B (NF-κB) plays a key regulatory role in host cells. We have shown that preincubation with Bifidobacterium bifidum strain BF-1, a probiotic strain known to improve H. pylori-associated gastritis, suppresses induction of IL-8 by the pathogen. To investigate how how BF-1 affects gene expression in H. pylori-infected cells, we performed microarray analysis to assess gene expression in epithelial cells, which had been preincubated with BF-1 and infected with H. pylori. We found that preincubation with BF-1 suppresses the expression of H. pylori-induced genes in human cells and that most of the affected genes are related to the NF-κB signaling pathways. These results suggest that BF-1 can affect the regulatory mechanism of the NF-κB signaling pathways.     

Improved viability of bifidobacteria in fermented milk by cocultivation with Lactococcus lactis subspecies lactis

The poor survival of probiotic bacteria in commercial yogurts may limit their potential to exert health benefits in humans. The objective was to improve the survival of bifidobacteria in fermented milk. Cocultivation with some strains of Lactococcus lactis ssp. lactis improved the survival of bifidobacteria in fermented milk during refrigerated storage. Studies on one strain, Lc. lactis ssp. lactis MCC866, showed that the concentrations of dissolved oxygen were kept lower in the cocultivated fermented milk during storage compared with monocultured Bifidobacterium longum BB536 or samples cocultured with another noneffective Lc. lactis ssp. lactis strain. Degradation of genomic DNA was suppressed in the cocultivating system with Lc. lactis ssp. lactis MCC866. Several genes that participated in protection from active oxygen species (e.g., genes coding for alkyl hydroperoxide reductase and Fe²⁺ transport system) were expressed at higher levels during refrigerated storage in Lc. lactis ssp. lactis MCC 866 compared with another noneffective Lc. lactis ssp. lactis strain. Concentration of free iron ion was also lower in supernatants of fermented milk cocultivated with B. longum BB536 and Lc. lactis ssp. lactis MCC866. These results suggest that Lc. lactis ssp. lactis MCC 866 is potentially superior in reducing oxygen damage and consequently improves the survival of bifidobacteria in the cocultivating system. This cocultivation system is of industrial interest for producing fermented milk containing viable bifidobacteria with long shelf life.     

Clostridial spore germination versus bacilli: genome mining and current insights

Bacilli and clostridia share the characteristic of forming metabolically inactive endospores. Spores are highly resistant to adverse environmental conditions including heat, and their ubiquitous presence in nature makes them inevitable contaminants of foods and food ingredients. Spores can germinate under favourable conditions, and the following outgrowth can lead to food spoilage and foodborne illness. Germination of spores has been best studied in Bacillus species, but the process of spore germination is less well understood in anaerobic clostridia. This paper describes a genome mining approach focusing on the genes related to spore germination of clostridia. To this end, 12 representative sequenced Bacillus genomes and 24 Clostridium genomes were analyzed for the distribution of known and putative germination-related genes and their homologues. Overall, the number of ger operons encoding germinant receptors is lower in clostridia than in bacilli, and some Clostridium species are predicted to produce cortex-lytic enzymes that are different from the ones encountered in bacilli. The in silico germination model constructed for clostridia was linked to recently obtained experimental data for selected germination determinants, mainly in Clostridium perfringens. Similarities and differences between germination mechanisms of bacilli and clostridia will be discussed.     

Fusarium sibiricum sp. nov, a novel type A trichothecene-producing Fusarium from northern Asia closely related to F. sporotrichioides and F. langsethiae

Production of type A trichothecenes has been reported in the closely related species Fusarium langsethiae and F. sporotrichioides. Here, we characterized a collection of Fusarium isolates from Siberia and the Russian Far East (hereafter Asian isolates) that produce high levels of the type A trichothecene T-2 toxin and are similar in morphology to the type A trichothecene-producing F. langsethiae, and to F. poae which often produces the type B trichothecene nivalenol. The Asian isolates possess unique macroscopic and microscopic characters and have a unique TG repeat in the nuclear ribosomal intergenic spacer (IGS rDNA) region. In Asian isolates, the TRI1-TRI16 locus, which determines type A versus type B trichothecene production in other species, is more similar in organization and sequence to the TRI1-TRI16 locus in F. sporotrichioides and F. langsethiae than to that in F. poae. Phylogenetic analysis of the TRI1 and TRI16 gene coding regions indicates that the genes in the Asian isolates are more closely related to those of F. sporotrichioides than F. langsethiae. Phylogenetic analysis of the beta-tubulin, translation elongation factor, RNA polymerase II and phosphate permease gene sequences resolved the Asian isolates into a well-supported sister lineage to F. sporotrichioides, with F. langsethiae forming a sister lineage to F. sporotrichioides and the Asian isolates. The Asian isolates are conspecific with Norwegian isolate IBT 9959 based on morphological and molecular analyses. In addition, the European F. langsethiae isolates from Finland and Russia were resolved into two distinct subgroups based on analyses of translation elongation factor and IGS rDNA sequences. Nucleotide polymorphisms within the IGS rDNA were used to design PCR primers that successfully differentiated the Asian isolates from F. sporotrichioides and F. langsethiae. Based on these data, we formally propose that the Asian isolates together with Norwegian isolate IBT 9959 comprise a novel phylogenetic species, F. sibiricum, while the two subgroups of F. langsethiae only represent intraspecific groups.