scholarly journals Optimization of laboratory conditions for biosynthesis of type A trichothecenes

2007 ◽  
pp. 35-44 ◽  
Author(s):  
Aleksandra Bocarov-Stancic ◽  
Vesna Jacevic ◽  
Radmila Resanovic ◽  
Milorad Bijelic
Keyword(s):  
Type A ◽  
Climatic Conditions ◽  
Medium Composition ◽  
Fusarium Sporotrichioides ◽  
Metabolic Characteristics ◽  
Laboratory Conditions ◽  
Type A Trichothecenes ◽  
C And N ◽  
Definition Of

Type A trichothecenes, T-2 toxin and diacetoxyscirpenol - DAS, belong to one of the most toxic groups of fusariotoxins. Although larger quantities of them can be found more often in cooler parts of Europe, regarding their metabolic characteristics and the types of illnesses they provoke, it is obvious that even smaller quantities of these toxins can cause serious health disturbances of humans and animals in climatic conditions of Serbia. Having in mind the importance of these substances, the aim of this study was to carry out the optimization of laboratory conditions under which screening of Fusarium spp. isolates from Serbia, regarding T-2 toxin and DAS production, should be done. Four cultures of Fusarium sporotrichioides originating from different regions throughout the world, were under present investigation: ITM-391 (Italy), KF-38/1 (Poland), M-1-1 (Japan) and R-2301 (Germany). According to the previous literature data, all of these isolates were T-2 toxin producers, and some of them were also DAS producers. The influence of medium composition (different C and N atoms sources microelements etc), as well as aeration (in liquid media), on biosynthesis process of these mycotoxins, in vitro conditions was investigated. In the case of most Fusarium sporotrichioides isolates, highest yields of T-2 toxin and DAS were achieved under the conditions of more intense aeration, and with the use of glucose (5 or 20%) as a C atom source. Fermentation in semi-synthetic liquid medium, using a rotary shaker, was more suitable for screening the toxicity of the fungal isolates in pure culture because of shorter period of incubation, more simpler sample preparation, obtaining less interfering materials in crude toxin extracts, and possibility for more precise definition of factors influencing the yield of trichothecenes.

scholarly journals The toxigenic potential of Fusarium poae originated from wheat

2007 ◽  
pp. 113-123 ◽  
Author(s):  
Aleksandra Bocarov-Stancic ◽  
Jelena Levic ◽  
Slavica Stankovic ◽  
Vesna Krnjaja ◽  
Tamara Kovacevic ◽  
...  
Keyword(s):  
Liquid Medium ◽  
Room Temperature ◽  
Liquid Culture ◽  
Type A ◽  
Control Culture ◽  
Climatic Conditions ◽  
Chromatography Method ◽  
Ear Blight ◽  
Type A Trichothecenes ◽  
Layer Chromatography

Eleven isolates of F. poae, originated from wheat grain at 9 locations mainly in Vojvodina, were encompassed by the present study. The greatest number of samples was collected in 2005, in which the climatic conditions favoured a more intensive occurrence of Fusarium ear blight of wheat. In order to determine toxicological potential of this species, cultures of the selected isolates were grown in liquid media (GPY and SPY) on a rotary shaker (180 revolutions min-1), at room temperature (21-26?C) for three days. Crude toxins were isolated from liquid culture filtrates of isolates by the use of ethyl acetate, while quantification of mycotoxins was done by the thin layer chromatography method. A liquid culture of the isolate GZ-LES (F. graminearum) was used as a control for the evaluation of the zearalenone biosynthesis potential. On the other hand, the liquid culture of the isolate KF-38/1 (F. sporotrichioides) was used as a control for both type-A trichothecenes (T-2 toxin and diacetoxyscirpenol - DAS). The obtained results show that F. poae, in contrast to F. graminearum, has no potential for the zearalenone biosynthesis. The presence of DAS was determined only in one isolate of F. poae (MRIZP-666), and in the control isolate of F. sporotrichioides (KF-38/1/R), that were grown in the GPY liquid medium. The T-2 toxin was detected in the isolate MRIZP-666, grown in both media, and in the isolates MRIZP-37 and MRIZP-860, cultured in the GPY and SPY liquid medium, respectively. The control culture KF-38/1/R (F. sporotrichioides) produced the T-2 toxin at the concentration of 4,000 ?g L-1. According to the gained information, it can be concluded that the potential of F. poae for the type-A trichothecene biosynthesis was low, as the concentration of DAS or T-2 toxin did not exceed 80 ?g L-1 or 240 ?g L-1, respectively.

scholarly journals In vitro degradation of diacetoxyscirpenol and T-2 toxin by use of Mucor racemosus fresen. f. racemosus isolate

2011 ◽  
pp. 51-59 ◽  
Author(s):  
Aleksandra Bocarov-Stancic ◽  
Slavica Stankovic ◽  
Jelena Levic ◽  
Natasa Salma ◽  
Vladimir Pantic ◽  
...  
Keyword(s):  
Mixed Culture ◽  
Membrane Filter ◽  
Type A ◽  
Mucor Racemosus ◽  
Nutritive Medium ◽  
Liquid Cultures ◽  
Fusarium Semitectum ◽  
Type A Trichothecenes ◽  
Incubation Duration

Under controlled in vitro conditions the capacity of the Mucor racemosus f. racemosus 1215/09 isolate to degrade type A trichothecenes (diacetoxyscirpenol - DAS and T-2 toxin) was observed in the liquid nutritive medium. According to previously performed experiments it was proved that the selected isolate, originating from sunflower meal, had the ability to degrade these fusariotoxins when growing on the modified Vogel?s agar supplemented with crude extracts of DAS and T-2 toxin. In order to determine biodegradation of fusariotoxins, the liquid nutritive medium - SPY (5% sucrose + 0.1% peptone + 0.1% yeast extract, pH 6.2) was simultaneously inoculated with the isolate M. racemosus f. racemosus 1215/09 and: a) Fusarium semitectum SL-B (DAS producer) or b) F. sporotrichioides R-2301 (T-2 toxin producer). The SPY media, inoculated with single fungal isolates, were used as a control of toxin biosynthesis. The cultures were incubated at room temperature (21-26?C) on the rotary shaker (175 rpm). After the 3-5-day incubation, the filtration of liquid cultures and the extraction of fusariotoxins from filtrates with ethyl-acetate were performed. Determinations of DAS and T-2 toxin were done by thin layer chromatography using silica gel G. Depending on the incubation duration, M. racemosus f. racemosus in the mixed culture with F. semitectum degraded from 90.0 to 99.97% of DAS present in the medium (40,000- 120,000 ?g l-1), while in the mixed culture with F. sporotrichioides it degraded from 95.0 to 96.7% of T-2 toxin present in the medium (240,000 ?g l-1). Sterile filtrates of mixed cultures and single culture of M. racemosus f. racemosus, obtained by passing liquid cultures through the 0.45-?m membrane filter and added to the SPY medium, did not affect degradation of type A trichothecenes that had been biosynthesised by isolates F. semitectum SL-B and F. sporotrichioides R-2301 in the liquid medium.

scholarly journals Fusarium Sporotrichioides Sherb. Toxins Evaluated in Cereal Grain with Trichoderma Harzianum

2011 ◽  
Vol 51 (2) ◽  
pp. 134-139 ◽  
Author(s):  
Halina Wiśniewska ◽  
Tomasz Basiński ◽  
Jerzy Chełkowski ◽  
Juliusz Perkowski
Keyword(s):  
Liquid Medium ◽  
Trichoderma Harzianum ◽  
Plant Pathogens ◽  
Total Concentration ◽  
Type A ◽  
Fusarium Sporotrichioides ◽  
Head Blight ◽  
Naked Oat ◽  
Cereal Grain ◽  
Type A Trichothecenes

Fusarium SporotrichioidesSherb. Toxins Evaluated in Cereal Grain withTrichoderma HarzianumFusariumhead blight is one of the most severe diseases of small grain cereals and is caused by several toxigenicFusariumspecies. Yield losses and mycotoxin accumulation in grain are caused by the disease.F. sporotrichioidesandF. poaeproduce type A trichothecenes. Saprophyte fungal antagonists, especiallyTrichoderma harzianum, are effective biocontrol agents against several fungal soil-borne plant pathogens. These fungal antagonists can reduce the production ofFusariumspp. mycotoxins in some crop plants. The aim of this study was to examine the influence ofT. harzianumAN4 on the production of type A trichothecenes byF. sporotrichioidesin cereals. The accumulation of six trichothecene mycotoxins (scirpentriol,i.e.STO, T-2 tetraol, T-2 triol, HT-2 toxini.e., HT-2, T-2 toxini.e., T-2, diacetoxyscirpenol,i.e., DAS) was reduced on average, by over 89% in bioassays ofF. sporotrichioidesandTrichodermaisolate AN4 on a liquid medium and on solid substrates (seeds of naked and husked oats and wheat). The reduction in our experiments depended on fungal isolate and substrate. From the three isolates ofF. sporotrichioidesused in the experiments, the highest accumulation of all the metabolites after 21 days byF. sporotrichioidesin nearly all substrates, was recorded for strain ZFR 159. On the liquid medium inoculated withF. sporotrichioidesZFR 159, the amount of type A trichothecenes was the lowest (STO, T-2 tetraol, and T-2 triol not detected, HT-2 toxin 0.02 ppm, DAS 0.10 ppm, T-2 toxin 0.99 ppm). The highest total concentration of these toxins was produced by this isolate in husked oat cv. German (180.16 ppm), but in naked oat cv. Akt the toxin concentration was low (27.62 ppm). Trichothecene accumulation byT. harzianumAN4 was reduced the most in oat cv. Akt (98.48%) in the liquid medium (98.22%), while the lowest reduction was in oat cv. German (48.77%). The non-toxigenicT. harzianumAN4 isolate proved to be a useful biocontrol agent against the toxigenicF. sporotrichioidesin cereals, significantly reducing the production of six type A trichothecenes. This is the first report on effective biocontrol ofF. sporotrichioidesin cereals byT. harzianum.

scholarly journals Phylogenetic diversity, trichothecene potential, and pathogenicity within Fusarium sambucinum species complex

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245037
Author(s):  
Imane Laraba ◽  
Susan P. McCormick ◽  
Martha M. Vaughan ◽  
David M. Geiser ◽  
Kerry O’Donnell
Keyword(s):  
Species Complex ◽  
Plant Pathogens ◽  
Novel Species ◽  
Type A ◽  
Distinct Species ◽  
Fusarium Sambucinum ◽  
In Planta ◽  
Strain Collection ◽  
Type A Trichothecenes

The Fusarium sambucinum species complex (FSAMSC) is one of the most taxonomically challenging groups of fusaria, comprising prominent mycotoxigenic plant pathogens and other species with various lifestyles. Among toxins produced by members of the FSAMSC, trichothecenes pose the most significant threat to public health. Herein a global collection of 171 strains, originating from diverse hosts or substrates, were selected to represent FSAMSC diversity. This strain collection was used to assess their species diversity, evaluate their potential to produce trichothecenes, and cause disease on wheat. Maximum likelihood and Bayesian analyses of a combined 3-gene dataset used to infer evolutionary relationships revealed that the 171 strains originally received as 48 species represent 74 genealogically exclusive phylogenetically distinct species distributed among six strongly supported clades: Brachygibbosum, Graminearum, Longipes, Novel, Sambucinum, and Sporotrichioides. Most of the strains produced trichothecenes in vitro but varied in type, indicating that the six clades correspond to type A, type B, or both types of trichothecene-producing lineages. Furthermore, five strains representing two putative novel species within the Sambucinum Clade produced two newly discovered type A trichothecenes, 15-keto NX-2 and 15-keto NX-3. Strains of the two putatively novel species together with members of the Graminearum Clade were aggressive toward wheat when tested for pathogenicity on heads of the susceptible cultivar Apogee. In planta, the Graminearum Clade strains produced nivalenol or deoxynivalenol and the aggressive Sambucinum Clade strains synthesized NX-3 and 15-keto NX-3. Other strains within the Brachygibbosum, Longipes, Novel, Sambucinum, and Sporotrichioides Clades were nonpathogenic or could infect the inoculated floret without spreading within the head. Moreover, most of these strains did not produce any toxin in the inoculated spikelets. These data highlight aggressiveness toward wheat appears to be influenced by the type of toxin produced and that it is not limited to members of the Graminearum Clade.

EVALUATION OF TISSUE STEROID BINDING IN VITRO

1971 ◽  
Vol 68 (1_Suppl) ◽  
pp. S223-S246 ◽  
Author(s):  
C. R. Wira ◽  
H. Rochefort ◽  
E. E. Baulieu
Keyword(s):  
Protein Binding ◽  
Binding Sites ◽  
Experimental System ◽  
Specific Protein ◽  
Coupling Mechanism ◽  
Target Tissue ◽  
Protein Binding Sites ◽  
Definition Of ◽  
Hormone Specificity

ABSTRACT The definition of a RECEPTOR* in terms of a receptive site, an executive site and a coupling mechanism, is followed by a general consideration of four binding criteria, which include hormone specificity, tissue specificity, high affinity and saturation, essential for distinguishing between specific and nonspecific binding. Experimental approaches are proposed for choosing an experimental system (either organized or soluble) and detecting the presence of protein binding sites. Techniques are then presented for evaluating the specific protein binding sites (receptors) in terms of the four criteria. This is followed by a brief consideration of how receptors may be located in cells and characterized when extracted. Finally various examples of oestrogen, androgen, progestagen, glucocorticoid and mineralocorticoid binding to their respective target tissues are presented, to illustrate how researchers have identified specific corticoid and mineralocorticoid binding in their respective target tissue receptors.

Pertumbuhan Dan Perkembangan Anggrek Dendrobium anosmum Pada Media Kultur In Vitro Dengan Beberapa Konsentrasi Air Kelapa

Agrologia ◽  
2018 ◽  
Vol 1 (1) ◽  
Author(s):  
S. Tuhuteru ◽  
Meity L Hehanussa ◽  
Simon H.T Raharjo
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Water Concentration ◽  
Medium Composition ◽  
Coconut Water ◽  
Orchid Species ◽  
Randomized Design ◽  
Wet Weight ◽  
Completely Randomized Design

Dendrobium anosmum is one of natural orchids in Indonesia. Optimization of medium composition for orchid propagation through in vitro culture is necessary to enhance propagule multiplication capabilities and quality. This study was aimed to study the influence of concentration of coconut water in culture medium on in vitro growth and development of D. anosmum orchid species and to determine the optimal coconut water concentration in culture media.  The experiment were arranged in a Completely Randomized Design with four treatments and eight replications. The treatments consisted of the addition of coconut water with concentrations: 0 ml•l -1 (control), 50 ml•l-1, 100 ml•l-1 and 150 ml•l-1. The results showed that addition of coconut water in culture medium gave different effect on shoot growth and multiplication of D. anosmum orchids.  Coconut water concentration of 100 ml•l-1 was the best concentration for growth and multiplication of D. anosmum orchids, based on both shoots and roots growth, plantlet height and wet weight.

HELIOTHERAPY IN THE TREATMENT OF PSORIATIC ARTHRITIS

2018 ◽  
Vol 28 (2) ◽  
pp. 483-487
Author(s):  
Snezhina Georgieva ◽  
Dilyana Zvezdova
Keyword(s):  
Psoriatic Arthritis ◽  
Clinical Picture ◽  
Local Therapy ◽  
Severe Form ◽  
Climatic Conditions ◽  
Joint Disease ◽  
Immune Mediated ◽  
Social Comfort ◽  
Pigment Type ◽  
Definition Of

Psoriatic arthritis is an inflammatory joint disease associated with psoriasis vulgaris, with routinely negative rheumatoid factors and the absence of rheumatoid nodules. This is an immune-mediated disease, according to generally accepted definition of Wright and Moll from 1973. American Association against Rheumatism classified psoriatic arthritis as an independent disease in 1964. Psoriatic arthritis is a single disease with a varied clinical picture. It belongs to the group of seronegative spondyloarthropathies with which there are general clinical features. It is believed that similar mechanisms determine the onset of psoriasis and psoriatic arthritis. The clinical picture includes various clinical forms that damage the peripheral and sacroiliac joints, spine, internal organs. The treatment of psoriatic arthritis is directed simultaneously to the influence of skin and joint changes. Purpose: Our study aims to summarize our long-standing experience in the treatment of psoriatic arthritis with heliotherapy. Subject of observation: Monitoring includes 132 patients with moderate and severe form of psoriasis treated at the sanatorium in town of Pomorie for 5 years in the period 2001-2006. Results and discussion: 132 patients with psoriasis with no effect on the local therapy and have proven psoriatic arthritis were selected. In our climatic conditions, heliotherapy is appointed during the warm half-year. Sun treatment was conducted under the conditions of a healing beach, which had shielding, radiation-protective devices. In patients with erythema - pigment and pigment type skin reactivity begins with 1-2 bioadoses reached to 8-10 biodoses, carried out in the area of overcomfort. Conclusion: The studies demonstrated that heliotherapy combined with medications significantly improves the prognosis of patients with this disease. The ultimate success would mean overcoming the frequent depression conditions, better survival and social comfort for patients with psoriatic arthritis.

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