White cabbage (<Emphasis Type="Italic">Brassica oleracea</Emphasis> var. <Emphasis Type="Italic">capitata</Emphasis> f. <Emphasis Type="Italic">alba</Emphasis>): botanical,phytochemical and pharmacological overview

White cabbage (Brassica oleraceae var. capitata f. alba) is a cruciferous vegetable used worldwide as a food and in traditional medicine. Due to its common availability in local markets, affordability, and consumer preference, it represents a significant source of phytonutrients in the human diet. This review provides an overview of white cabbage origin, taxonomy, geographical distribution, botanical characteristics, and contemporary and traditional uses, as well as its phytochemicals and pharmacology. Special emphasis is placed on a health-promoting phytochemicals such as glucosinolates, polyphenols, and vitamins, as well as anticancerogenic, antioxidant, anti-inflamantory and cardioprotective effects. The majority of so far published research on white cabbage was focused on qualitative determination of phytochemicals (targeted analysis), while only few recent papers published data based on untargeted metabolomic profiling. Hence, this review discusses and emphasizes a further need of studying the white cabbage phytochemicals using modern metabolomics platforms which will enable scientists to pinpoint the exact bioactive metabolites which are responsible for certain bioactivity.     

Antimicrobial Activity of Essential Oils Against the Fungal Pathogens <Emphasis Type="Italic">Ascosphaera apis</Emphasis> and <Emphasis Type="Italic">Pseudogymnoascus destructans</Emphasis>

Fungal pathogens are a growing worldwide concern. Declines in a number of economically and agriculturally important plant and animal species pose a significant threat to both biodiversity and food security. Although many effective antifungal agents have been identified, their toxicity often precludes their use with food products or sensitive animal species. This has prompted the exploration of natural products as effective treatment compounds. In the present study, several essential oils were tested for their capacity to limit the growth of the fungal pathogens Ascosphaera apis and Pseudogymnoascus destructans, the causative agents of chalkbrood disease among honey bee larvae and white-nose syndrome among bats, respectively. Essential oils of cinnamon bark, citronella, lemongrass, and orange were exposed to A. apis in contact-dependent oil-agar suspensions as well as in contact-independent shared airspaces. Essential oils of cinnamon bark, citronella, and lemongrass were exposed to P. destructans in contact-dependent oil-agar suspensions. All compounds were found to significantly inhibit mycelial growth at low concentrations, suggesting the potential for these natural products to be used for controlling these and other select fungal pathogens.     

A new method of propagation of arbuscular mycorrhizal fungi in field cropped sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.)

Though arbuscular mycorrhizal (AM) fungi are indigenous to agricultural soils, their beneficial effects to host plants could be further improved by inoculation with efficient species. The method of AM propagation described in the present study uses oil cake as a supporting medium for the simultaneous delivery of sesame seeds and AM inoculum to the field. Experiment was conducted in a farmer’s field located at Avoor, Kerala, India where sesame was cultivated as a winter crop in rice fallows. Oil cake entrapped with sesame seeds (var. Tilatara) and AM fungus (Funneliformis dimorphicus) inoculum was prepared by thoroughly mixing sterilized coconut cake and neem cake (5:1 v/v), surface sterilized sesame seeds and sterilized spore sieving of F. dimorphicus from a pot culture in a 10% solution of a polysaccharide gum obtained from the seeds of Strychnos potatorum L. Entire mix was moulded into 2.5 cm cubes (ca. 5g) containing approximately 25–30 seeds and 200–300 spores cube^?1 and shade dried before application. The cubes were broadcast @ 600 kg ha^?1 in inoculated treatments. In uninoculated treatments, the oil cake cubes devoid of the fungal component was used. Harvested root samples from the inoculated treatments showed a high frequency (%F) and intensity (%M) of colonization by AM fungi as well as frequency of vesicles (%V) and arbuscules (%A) compared to uninoculated control. The growth (root length, shoot length and leaf area) and yield characters (pod number, seed number, seed weight and oil content) of sesame plants were significantly (p=0.05) improved under the present method of AM propagation indicating its viability under field condition.     

<Emphasis Type="SmallCaps">l</Emphasis>-Aspartate dehydrogenase: features and applications

l-Amino acid dehydrogenases are a group of enzymes that catalyze the reversible oxidative deamination of l-amino acids to their corresponding 2-oxoacids, using either nicotinamide adenine dinucleotide (NAD⁺) or nicotinamide adenine dinucleotide phosphate (NADP⁺) as cofactors. These enzymes have been studied widely because of their potential applications in the synthesis of amino acids for use in production of pharmaceutical peptides, herbicides and insecticides, in biosensors or diagnostic kits, and development of coenzyme regeneration systems for industrial processes. This article presents a review of the currently available data about the recently discovered amino acid dehydrogenase superfamily member l-aspartate dehydrogenase (l-AspDH), their relevant catalytic properties and speculated physiological roles, and potential for biotechnological applications. The proposed classification of l-AspDH on the basis of bioinformatic information and potential role in vivo into NadB (NAD biosynthesis-related) and non-NadB type is unique. In particular, the mesophilic non-NadB type l-AspDH is a novel group of amino acid dehydrogenases with great promise as potential industrial biocatalysts owing to their relatively high catalytic properties at room temperature. Considering that only a few l-AspDH homologs have been characterized so far, identification and prodigious enzymological research of the new members will be necessary to shed light on the gray areas pertaining to these enzymes.     

Low level of polymorphism in two putative <Emphasis Type="Italic">NPR1</Emphasis> homologs in the <Emphasis Type="Italic">Vitaceae</Emphasis>family

Background  

Grapevine is subjected to numerous pests and diseases resulting in the use of phytochemicals in large quantities. The will to decrease the use of phytochemicals leads to attempts to find alternative strategies, implying knowledge of defence mechanisms. Numerous studies have led to the identification of signalling pathways and regulatory elements involved in defence in various plant species. Nonexpressor of Pathogenesis Related 1 (NPR1) is an important regulatory component of systemic acquired resistance (SAR) in Arabidopsis thaliana.     

Screening and molecular identification of lactic acid bacteria from <Emphasis Type="Italic">gari</Emphasis> and <Emphasis Type="Italic">fufu</Emphasis> and <Emphasis Type="Italic">gari</Emphasis> effluents

Bacterial strains were isolated from cassava-derived food products and, for the first time, from cassava by-products, with a focus on gari, a flour-like product, and the effluents from the production processes for gari and fufu (a dough also made from cassava flour). A total of 47 strains were isolated, all of which were tested to determine their resistance to acidic pH and to bile salt environments. Four of the 47 isolates tested positive in both environments, and these four isolates also showed antibacterial behaviour towards both Gram-positive and Gram-negative microbial pathogens (i.e. Methicillin-resistance Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Salmonella enteritidis, Escherichia coli, Escherichia coli (O157), Yersinia enterocolitica). In most cases, the antibacterial activity was related to bacteriocin production. Molecular identification analysis (16S rDNA and randomly amplified polymorphic DNA-PCR) revealed that the four isolates were different strains of the same species, Lactobacillus fermentum. These results demonstrate that bacteria isolated from cassava-derived food items and cassava by-products have interesting properties and could potentially be used as probiotics.     

Feeding rate of sibling vole <Emphasis Type="Italic">Microtus rossiaemeridionalis</Emphasis> and mandarin vole <Emphasis Type="Italic">Lasiopodomys mandarinus</Emphasis> housed in cages and enclosures

Consumption of food of different nutritive value by sibling vole Microtus rossiaemeridionalis and mandarin vole Lasiopodomys mandarinus as a function of housing conditions—in cages or enclosures—was comparatively studied. Experimental groups included 8–14 adult non-reproducing animals of both sexes kept one per cage or enclosure. The rate of food consumption and digestibility were studied by standard methods and the obtained data were statistically analyzed using Statistica 6.0. Significant differences in the rate of food consumption by mandarin voles housed under different conditions as well as in the consumption and digestibility of food of different biochemical composition in both vole species have been revealed.     

Carotenoids from <Emphasis Type="Italic">Rhodotorula</Emphasis> and <Emphasis Type="Italic">Phaffia</Emphasis>: yeasts of biotechnological importance

Carotenoids represent a group of valuable molecules for the pharmaceutical, chemical, food and feed industries, not only because they can act as vitamin A precursors, but also for their coloring, antioxidant and possible tumor-inhibiting activity. Animals cannot synthesize carotenoids, and these pigments must therefore be added to the feeds of farmed species. The synthesis of different natural commercially important carotenoids (β-carotene, torulene, torularhodin and astaxanthin) by several yeast species belonging to the genera Rhodotorula and Phaffia has led to consider these microorganisms as a potential pigment sources. In this review, we discuss the biosynthesis, factors affecting carotenogenesis in Rhodotorula and Phaffia strains, strategies for improving the production properties of the strains and directions for potential utility of carotenoid-synthesizing yeast as a alternative source of natural carotenoid pigments.     

Limitations of <Emphasis Type="Italic">Neoseiulus baraki</Emphasis> and <Emphasis Type="Italic">Proctolaelaps bickleyi</Emphasis> as control agents of <Emphasis Type="Italic">Aceria guerreronis</Emphasis>

Several predatory mites have been found in association with the coconut mite, Aceria guerreronis Keifer, in northeast Brazil. However, the latter still causes damage to coconut in that region. The objectives of this work were to compare the frequencies of occurrence of Neoseiulus (Phytoseiidae) and Proctolaelaps (Melicharidae) species on standing and aborted coconuts in coastal Pernambuco State, northeast Brazil and to analyze their possible limitations as control agents of the coconut mite, based on evaluations of the restrictions they may have to access the microhabitat inhabited by the pest and their functional and reproductive responses to increasing densities of the latter. Neoseiulus baraki (Athias-Henriot) was found mostly on standing coconuts whereas Proctolaelaps bickleyi (Bram) was found mostly on aborted coconuts. Measurements of the entrance to the microhabitat occupied by the coconut mite, between the bracts and the subjacent fruit surface, showed that this different pattern of predator prevalence could be related to predator sizes, although other environmental factors could not be disregarded. Progressively higher predation rate of N. baraki was observed up to an experimental density that corresponded to 1,200 coconut mites per fruit, which is close to the average number determined in northeast Brazil, reducing slightly afterwards. Predation rate of P. bickleyi reduced consistently but slightly with increasing prey densities, but in absolute values, rates were always much higher than determined for N. baraki. The excessively high killing capacity of P. bickleyi, probably related to its high feeding requirement, may be detrimental in terms of stability. In fact, such high requirement for food suggests that P. bickleyi might not have a strong relation with the coconut mite and that the latter may not be its main food source under natural conditions. It is concluded that body sizes of both predators and the exceedingly high feeding requirement of P. bickleyi may limit their performance as control agents of the coconut mite.     

The tyrosine <Emphasis Type="Italic">O</Emphasis>-prenyltransferase SirD catalyzes <Emphasis Type="Italic">O</Emphasis>-, <Emphasis Type="Italic">N</Emphasis>-, and <Emphasis Type="Italic">C</Emphasis>-prenylations

Recently, the prenyltransferase SirD was found to be responsible for the O-prenylation of tyrosine in the biosynthesis of sirodesmin PL in Leptosphaeria maculans. In this study, the behavior of SirD towards phenylalanine/tyrosine and tryptophan derivatives was investigated. Product formation has been observed with 12 of 19 phenylalanine/tyrosine derivatives. It was shown that the alanine structure attached to the benzene ring and an electron donor, e.g., OH or NH₂, at its para-position are essential for the enzyme activity. Modifications were possible both at the side chain and the benzene ring. Enzyme products from seven phenylalanine/tyrosine derivatives were isolated and characterized by MS and NMR analyses including HSQC and HMBC and proven to be O- or N-prenylated derivatives at position C4 of the benzene rings. K _M values of six selected derivatives were found in the range of 0.10–0.68 mM. Catalytic efficiencies (K _cat/K _M ) were determined in the range of 430–1,110 s⁻¹·M⁻¹ with l-tyrosine as the best substrate. In addition, 7 of 14 tested tryptophan analogs were also accepted by SirD and converted to C7-prenylated derivatives, which was confirmed by comparison with products obtained from enzyme assays using a 7-dimethylallyltryptophan synthase 7-DMATS from Aspergillus fumigatus.     

Characterization of the <Emphasis Type="Italic">codY</Emphasis> gene and its influence on biofilm formation in <Emphasis Type="Italic">Bacillus </Emphasis><Emphasis Type="Italic">cereus</Emphasis>

The foodborne pathogen Bacillus cereus can form biofilms on various food contact surfaces, leading to contamination of food products. To study the mechanisms of biofilm formation by B. cereus, a Tn5401 library was generated from strain UW101C. Eight thousand mutants were screened in EPS, a low nutrient medium. One mutant (M124), with a disruption in codY, developed fourfold less biofilm than the wild-type, and its defective biofilm phenotype was rescued by complementation. Addition of 0.1% casamino acids to EPS prolonged the duration of biofilms in the wild-type but not codY mutant. When decoyinine, a GTP synthesis inhibitor, was added to EPS, biofilm formation was decreased in the wild-type but not the mutant. The codY mutant produced three times higher protease activity than the wild-type. Zymogram and SDS-PAGE data showed that production of the protease (∼130 kDa) was repressed by CodY. Addition of proteinase K to EPS decreased biofilm formation by the wild-type. Using a dpp-lacZ fusion reporter system, it was shown that that the B. cereus CodY can sense amino acids and GTP levels. These data suggest that by responding to amino acids and intracellular GTP levels CodY represses production of an unknown protease and is involved in biofilm formation.     

Mining <Emphasis Type="Italic">Xanthomonas</Emphasis> and <Emphasis Type="Italic">Streptomyces</Emphasis> genomes for new pectinase-encoding sequences and their heterologous expression in <Emphasis Type="Italic">Escherichia coli</Emphasis>

Microbial genome sequencing has left a legacy of annotated yet uncharacterized genes or open reading frames, activities that may have useful applications in health and/or the environment. We are interested in the discovery and characterization of potentially new pectinolytic activities for the enzymatic retting of natural bast fibers such as hemp and flax. A highlight in this study is the discovery of a cold-active pectate lyase among five pectate-lyase-encoding sequences and two polygalacturonase-encoding sequences that we have cloned from the genomes of Xanthomonas campestris pv. campestris and Streptomyces coelicolor A3(2). Heterologous expression of these sequences as active pectate lyases and polygalacturonases required their subcloning in Escherichia coli Rosetta™ cells. The most active recombinant pectate lyase (XcPL NP_638163), a cold-active pectate lyase (XcPL NP_636037), and a polygalacturonase (XcPG NP_638805) were purified to near homogeneity and their kinetic parameters were determined. A significant amount of pectin degradation products was shown to be released by the two pectate lyases but not the polygalacturonase when hemp fiber pectin was used as substrate. Results of this study showed that genome data mining, besides an economical approach to new gene acquisition, may uncover new findings such as the discovery of a cold-active pectate-lyase-encoding sequence from X. campestris, a mesophilic microorganism.     

Isolation and characterization of <Emphasis Type="Italic">Bacillus</Emphasis><Emphasis Type="Italic">polyfermenticus</Emphasis> isolated from <Emphasis Type="Italic">Meju,</Emphasis> Korean soybean fermentation starter

Bacteria of the Bacillus species have been reported as an important microorganism in fermented soybean products. In the present study, thirty Bacillus isolates were screened from Meju, a Korean soybean fermentation starter. The comparative analysis of 16S rDNA sequences, 16S-23S internal transcribed spacer sequences, phenotypic, and biochemical characterizations revealed three phylogenetically distinct groups namely Bacillus atrophaeus, Bacillus polyfermenticus and Bacillus subtilis. The isolates were assayed for poly-γ-glutamate production and fibrinolytic activity. Among the isolates, B. polyfermenticus exhibited maximum poly-γ-glutamate production and fibrinolytic activity. Moreover, the soybean products fermented by B. polyfermenticus have increased the time taken for coagulation and hemorrhage in mice. The results of the present study clearly indicate the functional role of B. polyfermenticus in fermented soybean products.     

Anti-oxidant,hemolysis inhibition,and collagen-stimulating activities of a new hexapeptide derived from <Emphasis Type="Italic">Arthrospira</Emphasis> (<Emphasis Type="Italic">Spirulina</Emphasis>) <Emphasis Type="Italic">platensis</Emphasis>

In this study, the whole protein of Arthrospira (Spirulina) platensis was extracted and hydrolyzed with trypsin. Screening process for new peptides was driven by 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity assay, and a hexapeptide with sequence of GMCCSR was identified. Its anti-oxidant activity was measured based on ABTS, 1,1’-diphenyl-2-picrylhydrazyl (DPPH), and ferric reducing ability of plasma (FRAP) assays. Hemolysis inhibition on human erythrocytes and collagen-stimulating activities on human skin fibroblasts (HSFs) were investigated. Results showed that its radical scavenging effect could compete with ascorbic acid. Intracellular assays revealed the reduction of reactive oxygen species (ROS) and malondialdehyde (MDA) contents and the increase in activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in erythrocytes pretreated with hexapeptide, demonstrating that the peptide could protect erythrocytes from lipid peroxidation and protein oxidation. Moreover, results from HSFs showed that it could promote proliferation and collagen production of HSFs pro-damaged by UVB. These results suggest the potential of the hexapeptide in food and pharmaceutical industries.     

Multiple paternity in <Emphasis Type="Italic">Rhipicephalus</Emphasis> (<Emphasis Type="Italic">Boophilus</Emphasis>) <Emphasis Type="Italic">microplus</Emphasis> confirmed by microsatellite analysis

The aim of this study was to determine if individual ticks among the progeny of a single female Rhipicephalus (Boophilus) microplus tick removed from cattle under natural conditions are the result of mating with one or several males. To this end, simulations were run using an existing dataset of genotypes from 8 microsatellite loci to predict the number of samples required and the best locus. Subsequently, 14–22 progeny from each of 15 engorged female ticks removed from three cows, and the engorged females themselves, were genotyped for the BmM1 locus and the minimum number of potential male parents was determined for each progeny group. Of the 15 progeny groups, 10 must have been sired by more than one male, as indicated by the presence of five unique alleles among the progeny or three unique alleles that could not have been contributed by the female. This finding demonstrates multiple paternity in R. microplus.     

Production of functionalized polyhydroxyalkanoates by genetically modified <Emphasis Type="Italic">Methylobacterium extorquens</Emphasis> strains

Background  

Methylotrophic (methanol-utilizing) bacteria offer great potential as cell factories in the production of numerous products from biomass-derived methanol. Bio-methanol is essentially a non-food substrate, an advantage over sugar-utilizing cell factories. Low-value products as well as fine chemicals and advanced materials are envisageable from methanol. For example, several methylotrophic bacteria, including Methylobacterium extorquens, can produce large quantities of the biodegradable polyester polyhydroxybutyric acid (PHB), the best known polyhydroxyalkanoate (PHA). With the purpose of producing second-generation PHAs with increased value, we have explored the feasibility of using M. extorquens for producing functionalized PHAs containing C-C double bonds, thus, making them amenable to future chemical/biochemical modifications for high value applications.