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Abstract

Antibiotic resistance is endangering public health globally and gives reason for constant fear of virtually intractable bacterial infections. Given a limitation of novel antibiotic classes brought to market in perspective, it is indispensable to explore novel, antibiotics-independent ways to fight bacterial infections. In consequence, the antibacterial properties of natural compounds have gained increasing attention in pharmacological sciences. We here performed a literature survey regarding the antibacterial effects of capsaicin and its derivatives constituting natural compounds of chili peppers. The studies included revealed that the compounds under investigation exerted i.) both direct and indirect antibacterial properties in vitro depending on the applied concentrations and the bacterial strains under investigation; ii.) synergistic antibacterial effects in combination with defined antibiotics; iii.) resistance-modification via inhibition of bacterial efflux pumps; iv.) attenuation of bacterial virulence factor expression; and v.) dampening of pathogen-induced immunopathological responses. In conclusion, capsaicin and its derivatives comprise promising antimicrobial molecules which could complement or replace antibiotic treatment strategies to fight bacterial infections. However, a solid basis for subsequent clinical trials requires future investigations to explore the underlying molecular mechanisms and in particular pharmaceutical evaluations in animal infection models.

Open access

Abstract

The excessive prescription of antibiotics has led to an increasing number of antimicrobial resistances, posing a major public health concern. Therefore, the pharmacological research has shifted its focus to the identification of natural compounds that exhibit anti-pathogenic properties without triggering antibiotic resistance. Butyrate has received increasing attention as a promising candidate for the treatment of bacterial infections in the gastrointestinal tract, particularly when antibiotic treatment is contraindicated. This literature survey summarizes recently investigated antibacterial and immune-modulatory effects of butyrate. This survey revealed that butyrate exerts direct antimicrobial effects against distinct strains of Acinetobacter baumannii, Escherichia coli, Bacillus, and Staphylococcus species. In addition, in vitro and in vivo studies confirmed indirect antimicrobial effects of butyrate, which were exhibited via induction of host defensin production as well as by activation of innate and adaptive immune responses. Finally, the synergistic action of butyrate in combination with other antimicrobial compounds results in a striking clearance of bacterial pathogens. In conclusion, butyrate and its derivatives might be considered as promising antibacterial and immune-modulatory agents in order to tackle bacterial infections without antibiotics.

Open access

The efficacy of single and combined application of Trichoderma harzianum and Pseudomonas fluorescens (CHA0) in the controlling of Meloidogyne javanica on tomato plants was evaluated under green house conditions. Seeds of the susceptible tomato cv. Early-Urbana were sown in clean plastic pots containing 1.5 kg steam sterilized soil. Four weeks after planting, the soil of each pot was infested with a suspension of 20 ml/kg soil of T. harzianum (106 spores/ ml) and a suspension of 15 ml/kg soil of P. fluorescens (CHA0) (108 CFU/ ml). Soil of other pots were infested with the two tested bio-agents together as a combined application. Seven days later, plants in all pots, except the controls, were inoculated with M. javanica at initial population densities of 1, 2 or 4 eggs/ cm3 soil. Sixty days after nematode inoculation, the parameters of plant growth and nematode reproduction were determined. Results showed that the nematode reproduction factor (Rf) on the plants infected with 1, 2 and 4 eggs/ cm3 decreased by 58, 63 and 31% after the single application of T. harzianum, 11, 33 and 12% after the single application of P. fluorescens (CHA0) and 43, 55 and 49% after the combined application of the bio-agents, respectively. Combined application of the two bio-agents was found to be the most effective in controlling the higher initial population density of the nematode (4 eggs/ cm3).

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Dr. Barnabás Nagy

(1921–2020), a naturalist, orthopterologist, agrozoologist and forward-looking ecologist covered a rich scientific career. In commemoration of his significant contribution to entomology, we attempt to shed some light on a selection of his achievements. While devoted to his chosen insect order, Orthoptera, he was sensitive also to problems coming from everyday’s practice in controlling pests in agriculture. Consequently, he dealt with various pest species, belonging to a variety of insect taxa (Coleoptera, Lepidoptera, Hymenoptera). He always put the actual problem in ecological context. This may have helped him to recognize the need for an ecological approach in plant protection and to develop the pioneering concept of biological / ecological pest management, published in Hungarian, as early as in 1957. When arguing for his concept, he criticized the surplus usages of toxic pesticides and provided guidelines for facilitating the beneficial activity of the natural enemies of pests. This way he prepared the way for integrated pest management (IPM), preceding the international mainstream of his age. He held an active part in the International Organization for Biological Control (IOBC), as a founder of the International Working Group of Ostrinia (IWGO), and was the Head of the Department of Zoology of the Plant Protection Institute, Budapest, Hungary. He held several positions in the Hungarian Entomological Society (President, vice-President, Secretary, committee member), to that society he was engaged for 80 years. Here we cite only some of his most important, original entomological papers. He regularly published also in journals for popular science and gave lectures for the young generations of entomologists.

Curriculum vitae in a nutshell

Open access

Gerbera (Gerbera jamesonii) is a popular ornamental plant cultivated all over the world. It is grown in beds, pots and used as cut-flower in making bouquets and for decoration in ceremonial functions. Gerbera has been commercially cultivated by a large number of growers in India as a primary source of income, therefore, has high socioeconomic impact in floriculture industry. The gerbera cultivation areas in India are increasing day by day due to its uses and the market demands. Its cultivation has been hampered by a variety of diseases that affect its flower quality and quantity. Of them, the viral and phytoplasma diseases cause considerable losses in gerbera cultivation. In this review, we have described about the disease symptoms, detection methods and identification of causal virus and phytoplasma pathogens affecting gerbera production worldwide and their disease management strategies opted by the researchers for production of pathogen-free plants.

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Mite species (Acari: Parasitiformes, Acariformes) living on foliage of brambles (Rubus sp.) were collected in Hungary, Austria and Slovakia. Four eriophyoid mite species (Acariformes: Eriophyoidea) associated with 14 Rubus taxa were identified. Female of Anthocoptes rubicolens Roivainen, 1953 is re-described, the male is described and illustrated from Rubus praecox Bertol., and recorded for the first time from R.bifrons Vest, R.clusii Borbás, R.grabowskii Weihe, R.praecocifrons Király et Trávn., Rubus ser. Rhamnifolii (Bab.) Focke, R.slavonicus Király, Trávn. et Žila, and R. solvensis W. Maurer. Anthocoptes rubicolens is a new species for the fauna of Hungary. Female of Epitrimerus rubi (Domes, 1960) is re-described, male and nymph are described and illustrated from R.bertramii G. Braun. Morphological differences distinguishing these species from the similar Anthocoptes rubi Domes and Epitrimerus gibbosus (Nalepa) are discussed. Out of the four identified phytoseiid species, Phytoseius juvenis Wainstein et Arutunjan (Parasitiformes: Phytoseiidae) was the most frequent predatory mite on the leaves of studied Rubus spp.

Open access

One of the most important diseases of pea is caused by Pea seed-borne mosaic virus (PSbMV), which has a relatively wide host range. Since there are few varieties with resistance against the virus, and spraying insecticides is not very effective, the determination of the disease and the pathogen in the seeds is very important. Inoculum prepared from pea seeds showing typical virus symptoms caused very mild symptoms on Chenopodium amaranticolor and C. quinoa, but several chlorotic/necrotic lesions on bean (Phaseolus vulgaris) cv. Scarlet, and systemic symptoms with mosaic and curling of top leaves on bean cv. Maxidor. The detection of the virus was carried out by PCR using universal primers and virus sequence analysis. According to the phylogenetic analysis the PSbMV isolate identified in Hungary belongs to the pathotype P1 and associated with the cluster 2 isolates.

Open access

Nagyelma n. gen. is erected for the northern Vietnamese Ennea aliena Bavay and Dautzenberg, 1912. The most closely related genus is probably Elma H. Adams, 1866, which also has a high-spired shell but differs from the new genus in the absence of a parietal tooth, the pointed-ovoid shell shape, and the penial sheath, which covers only half of the penis.

Open access

A new vagrant species of phyllocoptine mites, Leipothrix nagyi n. sp. collected from Zinnia elegans (Asteraceae) is described and illustrated from Hungary. Further three eriophyoid species were recorded for the first time in Hungary, viz. Aceria hippophaena (Nalepa, 1898) found on Hippophaë rhamnoides, Epitrimerus cupressi (Keifer, 1939) collected from Cupressus sempervirens and Epitrimerus tanaceti Boczek et Davis, 1984 associated with Tanacetum vulgare. The female of E.tanaceti is re-described, while the male and nymph are described for the first time.

Open access

Isoperla nagyi sp. n. is described on the basis of morphology of male and female adults and eggs. The new species is classified as an isolated species within the West Palaearctic Isoperla. It was found in the lower elevations of the Ţarcu Mts that is forming a high range of the westernmost Southern Carpathians. Further contributions are given on the stonefly fauna of the Ţarcu Mts, including notes on the Romanian distribution of Brachyptera bulgarica Raušer, and the taxonomy and distribution of Isoperla pusilla (Klapálek).

Open access