Identification and characterization of Bacillus spp. isolates with potential for biocontrol of white button mushroom fungal pathogens

Najštetniji patogeni šampinjona čija pojava u gajilištima izaziva velike gubitke u prinosu su gljive Trichoderma spp., prouzrokovači zelene plesni i Lecanicillium fungicola, prouzrokovač suve truleži šampinjona...The most devastating fungal pathogens of the white button mushroom that induced the greatest yield losses are Trichoderma spp. and Lecanicillium fungicola, causal agents of green mould and dry bubble disease..

Антибактеријска својства талусних јетрењача marchantia polymorpha l., conocephalum conicum (l.) dum. И pellia endiviifolia (dicks.) dumort.

The antimicrobial activity of methanol extracts of three thalloid liver­worts, Marchantia polymorpha, Conocephalum conicum and Pellia endiviifolia and bis-bibenzyl marchantin A, the most dominant compound in the methanol extract of M. polymorpha, have been investigated in this research. 1H-NMR spec­troscopy revealed that the M. polymorpha and P. endiviifolia extracts of liverwort contain terpenes, oils, sugars and bis-bibenzyls, while these specific macrocyclic compounds were absent in the C. conicum extract. The anti­mic­robial potential was tested on eight bacterial strains. Antimicrobial effects of extracts and mar­chantin A were observed against Gram-positive bacteria, while they showed no effect against Gram-negative bacteria in both methods used – well diffusion and broth microdilution.У овом раду испитиван је хемијски састав и антибактеријска активност метанолних екстраката три јетрењачe, Marchantia polymorpha, Conocephalum conicum и Pellia endiveifolia и бис-бибензила маршанцина A, доминантне компоненте у метанолном екстракту M. polymorpha. 1H-NMR спектроскопија је показала присуство терпена, уља, шећера и бис-бибензила у екстрактима M. polymorpha и P. endiviifolia, док екстракт C. conicum не садржи специфична макроциклична једињења – бис-бибензиле. Антимикробни потен- цијал је тестиран на осам бактеријских сојева. Антимикробни ефекат маршанцина А уочен је на све грам позитивне сојеве, док је ефекат изостао код грам негативних сојева у обе тестиране методе – дифузионе методе у бунарима и микродилуционе методе у хранљивом бујону

Uticaj treatiranja pokrivke biofungicidom na bazi Bacillus subtilis Ch-13 na suzbijanje zelene plesni i prinos šampinjona

The impact of a biofungicide based on Bacillus subtilis Ch-13 on mushroom yield and efficacy in suppression of Trichoderma aggressivum f. europaeum T77 from Serbia was estimated in comparision with a similar microbial fungicide, Bacillus velezensis QST713, and the chemical fungicide prochloraz manganese. The biofungicide B. velezensis QST713 is registered for treatments of mushrooms and other crops in many countries but it is not currently available on the Serbian market. The tested B. subtilis Ch-13 fungicide enhanced mushroom yield 12%, compared with an uninoculated control, and notably more than B. velezensis QST713 applied at its higher test concentrations. Regarding the efficacy of the biofungicides in control of the compost pathogen T. aggressivum f. europaeum, B. subtilis Ch-13 applied in concentration of 3 × 108 CFU per m2 showed higher efficacy than the higher concentrations (5 × 109 and 1 × 1010 CFU per m2) of B. velezensis QST713. The biofungicide based on B. subtilis Ch-13 should be further investigated regarding its different modes of application to ensure better efficacy in disease control as it showed beneficial features in both promoting A. bisporus production and suppressing the growth of the aggressive compost pathogen T. aggressivum, the causal agent of devastating green mould disease.Biofungicid na bazi Bacillus subtilis Ch-13 odabran je za procenu uticaja na prinos šampinjona i efikasnost u suzbijanju Trichoderma aggressivum f. europaeum T77 iz Srbije u poređenju sa sličnim mikrobiološkim fungicidom na bazi Bacillus velezensis QST713 i fungicidom prohloraz manganom. Biofungicid B. velezensis QST713 je registrovan u šampinjonima i drugim usevima u mnogim državama, ali nije dostupan na tržištu Sribje. Testirani B. subtilis Ch-13 je povećao prinos šampinjona 12% u poređenju sa neinokulisanom kontrolom i u značajno većoj meri od B. velezensis QST713 primenjenog u većim koncentracijama. U određivanju efikasnosti biofungicida u suzbijanju kompostnog patogena T. aggressivum f. europaeum, B. subtilis Ch-13 primenjen u koncentraciji 3 × 108 CFU po m2, ispoljio je veću efikasnost od B. velezensis QST713 primenjenog u većim koncentracijama (5 × 109 i 1 × 1010 CFU po m2). Biofungicid na bazi B. subtilis Ch-13 bi trebalo dalje testirati i proučiti različite načine njegove primene da bi se uspostavila veća efikasnost u suzbijanju patogena jer je pokazao značajne osobine u pospešivanju prinosa A. bisporus i zaštiti od agresivnog patogena iz komposta T. aggressivum, prouzrokovača zelene plesni šampinjona

Antioxidative Responses of Duckweed (Lemna minor L.) to Phenol and Rhizosphere-Associated Bacterial Strain Hafnia paralvei C32-106/3

Duckweed (L. minor) is a cosmopolitan aquatic plant of simplified morphology and rapid vegetative reproduction. In this study, an H. paralvei bacterial strain and its influence on the antioxidative response of the duckweeds to phenol, a recalcitrant environmental pollutant, were investigated. Sterile duckweed cultures were inoculated with H. paralvei in vitro and cultivated in the presence or absence of phenol (500 mg L−1), in order to investigate bacterial effects on plant oxidative stress during 5 days. Total soluble proteins, guaiacol peroxidase expression, concentration of hydrogen peroxide and malondialdehyde as well as the total ascorbic acid of the plants were monitored. Moreover, bacterial production of indole-3-acetic acid (IAA) was measured in order to investigate H. paralvei’s influence on plant growth. In general, the addition of phenol elevated all biochemical parameters in L. minor except AsA and total soluble proteins. Phenol as well as bacteria influenced the expression of guaiacol peroxidase. Different isoforms were associated with phenol compared to isoforms expressed in phenol-free medium. Considering that duckweeds showed increased antioxidative parameters in the presence of phenol, it can be assumed that the measured parameters might be involved in the plant’s defense system. H. paralvei is an IAA producer and its presence in the rhizosphere of duckweeds decreased the oxidative stress of the plants, which can be taken as evidence that this bacterial strain acts protectively on the plants during phenol exposure

Antagonistic potential of Bacillus spp. isolates against bacterial pathogens of tomato and fungal pathogen of pepper

In vitro antagonistic potential of eleven isolates of Bacillus spp. against two phytopathogenic bacteria and one fungus was tested in order to identify potential biocontrol agents in vegetable crops. The Bacillus spp. isolates demonstrated different levels of antagonistic effect against the tested pathogenic microorganisms. Data in the study proved Xanthomonas vesicatoria to be more sensitive to Bacillus spp. strains than Clavibacter michiganensis subsp. michiganensis. Ten B. subtilis strains induced growth inhibition of X. vesicatoria, while a strain of B. pumilus did not affect the growth of that bacterium. The largest inhibition zones against X. vesicatoria were induced by strains B-319, B-325 and B-358. The pathogenic strain C. michiganensis subsp. michiganensis was most inhibited by two B. subtilis strains (B-338 and B-348) with mean inhibition zone diameters of up to 20 mm. B. subtilis strain B-319 which was the best in inhibiting X. vesicatoria, showed the lowest inhibitory effect on C. michiganensis subsp. michiganensis. The largest growth inhibition percentage of Verticillium sp. (PGI approximately 70%) was induced by B. subtilis strains B-310 and B-322. The other B. subtilis strains showed PGI values ranging from 45% to 68%, while B. pumilus strain B-335 had the least antagonistic potential (PGI =34.43%) against the pathogen. This study identified at least one suitable biocontrol candidate, B. subtilis strain B-358, as effective in vitro against all three vegetable pathogens

Supplementary data for the article: Ljaljević Grbić, M.; Unković, N.; Dimkić, I.; Janaćković, P.; Gavrilović, M.; Stanojević, O.; Stupar, M.; Vujisić, L.; Jelikić, A.; Stanković, S.; et al. Frankincense and Myrrh Essential Oils and Burn Incense Fume against Micro-Inhabitants of Sacral Ambients. Wisdom of the Ancients? Journal of Ethnopharmacology 2018, 219, 1–14. https://doi.org/10.1016/j.jep.2018.03.003

Supplementary material for: [https://doi.org/10.1016/j.jep.2018.03.003]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2158

Culture-Dependent Analysis of 16S rRNA Sequences Associated with the Rhizosphere of Lemna minor and Assessment of Bacterial Phenol-Resistance: Plant/Bacteria System for Potential Bioremediation – Part II

In this work, we demonstrate that the rhizosphere of common duckweed (Lemna minor) is inhabited with various phenol-resistant bacterial strains. Based on 16S rRNA sequencing, we have identified 60 rhizosphere-associated bacterial isolates belonging to 10 different bacterial genera (Pseudomonas, Hafnia, Serratia, Enterobacter, Micrococcus, Stenotrophomonas, Xanthomonas, Bacillus, Staphylococcus and Klebsiella). All isolates have been tested for phenol resistance and ability to utilize phenol as the sole carbon source. 70% of all isolates survived high doses of phenol (≥200 mg/L) and at least 27% can be potentially acclimatized by gradual increase of phenol concentration. Finally, based on high phenol resistance, ability to utilize phenol as the sole carbon source and documented low pathogenicity, we propose 5 strains as potentially excellent candidates for bioremediation. These 5 strains taxonomically correspond to Klebsiella sp., Serratia sp., and Hafnia sp., respectively. To the best of our knowledge, this is the first attempt to assess decontamination capacity of Serratia nematodiphila and Hafnia sp. in the context of bioremediation of phenol-contaminated aqueous media. Although additional analyses are needed, interaction between the common duckweed and the selected bacterial strains may be utilized in future bioremediation strategies

Frankincense and myrrh essential oils and burn incense fume against micro-inhabitants of sacral ambients. Wisdom of the ancients?

Ethnopharmacological relevance: Essential oils obtained from resins of Boswellia carteri Birdw. and Commiphora myrrha (Nees) Engl., commonly known as frankincense and true myrrh respectively, have been used extensively since 2800 BCE for the treatment of skin sores, wounds, teeth, inflammation, and urinary tract diseases in traditional medicine; for preparation of mummification balms and unguents; and also as incense and perfumes. Since ancient times, burning of frankincense and myrrh in places of worship for spiritual purposes and contemplation (a ubiquitous practice across various religions) had hygienic functions, to refine the smell and reduce contagion by purifying the indoor air. Aim of the study: The general purpose of the study was to assess the in vitro antimicrobial potential of the liquid and vapour phases of B. carteri and C. myrrha essential oils and burn incense, as well as to test the effectiveness of their in situ application to cleanse microbially-contaminated air within the ambient of an investigated 17th century church. Materials and methods: The chemical composition of B. carteri and C. myrrha essential oils, obtained by hydro distillation of frankincense and true myrrh oleo gum resins was determined using GC/MS, and antimicrobial properties of their liquid and vapour phases were assessed by the broth microdilution and microatmosphere diffusion methods. Chemical analysis of burn incense fume obtained using bottle gas washing with dichloromethane as a solvent was performed by GC/MS, while its antimicrobial activity was evaluated using a modified microatmosphere diffusion method to evaluate germination inhibition for fungi and CFU count reduction for bacteria. The in situ antimicrobial activity of B. carteri burn incense and essential oil vapour phase was assessed in the sealed nave and diaconicon of the church, respectively. Results: The dominant compounds of B. carteri EO were a-pinene (38.41%) and myrcene (15.21%), while C. myrrha EO was characterized by high content of furanoeudesma-1,3-diene (17.65%), followed by curzerene (12.97%), f3-elemene (12.70%), and germacrene B (12.15%). Burn incense fume and soot had a-pinene (68.6%) and incensole (28.6%) as the most dominant compounds, respectively. In vitro antimicrobial assays demonstrated high bacterial and fungal sensitivity to the liquid and vapour phases of Eos, and burn incense fume. In situ application of B. carteri EO vapour and incense fume resulted in reduction of air -borne viable microbial counts by up to 45.39 +/- 2.83% for fungi and 67.56 +/- 3.12% for bacteria (EO); and by up to 80.43 +/- 2.07% for fungi and 91.43 +/- 1.26% for bacteria (incense fume). Conclusions: The antimicrobial properties of essential oil derived from frankincense, a compound with wellknown traditional use, showed that it possesses a clear potential as a natural antimicrobial agent. Moreover, the results suggest possible application of B. carteri EO vapour and incense fume as occasional air purifiers in sacral ambients, apart from daily church rituals.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/2931