Presence Of Alternaria Research Articles

Emerging Alternaria and Fusarium mycotoxins in tomatoes and derived tomato products from the China market: Occurrence, methods of determination, and risk evaluation

Emerging Alternaria and Fusarium mycotoxins are increasingly becoming a public health concern due to the frequent contamination of various food commodities with these mycotoxins, posing potential health risks to humans. This study developed QuEChERS extraction method coupled with LC–MS/MS for simultaneous quantification of alternariol monomethyl ether (AME), alternariol (AOH), tentoxin (TEN), tenuazonic acid (TeA), altenuene (ALT), enniatins (ENNs) A, A1, B, and B1, and beauvericin (BEA) in tomatoes and derived tomato products. The validated method was successfully applied for a survey of 194 tomatoes and derived tomato products. Overall, one or more mycotoxins were detected in 58.8% of the samples, 100% of tomato powders, 100% of canned tomatoes, 89.6% of tomato sauces, 82.1% of ketchups, 46.7% of tomato juices, and 20% of dried tomatoes, with no mycotoxins detected in fresh tomatoes. Various mycotoxins were detected at relatively higher contamination levels in tomato powders than in other tomato products. TeA, the most predominant mycotoxin, was detected in 56.7% of the samples with an occurrence level of up to 7,985 μg/kg. Approximately 39.2% of positive samples presented the co-occurrence of more than one mycotoxins, and AME + AOH + TeA was the most frequently detected combination. This study is the first to perform the deterministic risk assessment for children and adults on Alternaria and Fusarium mycotoxins that are present in tomatoes and derived tomato products in China. The results showed that the average and 95th percentile dietary exposures to these mycotoxins, especially to AME and AOH, in children might be higher than those in adults by a factor of approximately 2. The estimation of exposure to either Alternaria mycotoxins or Fusarium mycotoxins indicated that the presence of Alternaria and Fusarium mycotoxins in derived tomato products might be a health concern, especially among children and the populations consuming a high amount of these products. However, no firm conclusion could be drawn due to the lack of relevant in vivo toxicity data. This study serves as a useful reference for individuals and food safety authorities concerning mycotoxin contamination in food commodities. • Methods for emerging toxins determination in various tomato products were developed. • About 58.8% (114/194) of tomato-based products were contaminated with emerging toxins. • Co-occurrence of various emerging toxins was evident in 39.2% (76/194) of samples. • Dietary exposures to Alternaria and Fusarium toxins varied among children and adults.

Uticaj fitopatogenih gljiva na parametre kvaliteta semena boranije u periodu 2018-2022

Green beans are among the most essential legumes because of their nutritional value. However, the production of green beans in Serbia suffers major decline due to significantly reduced yields, as well as the sown areas. Diseases caused by phytopathogenic fungi not only reduce yield and have the negative impact on total germination and seed quality of green beans, but also some phytopathogenic fungi can produce mycotoxins, adversely affecting human health. In this paper, the quality parameters of two green bean varieties (GB1 and GB2) were monitored for quality traits over a period of five years on the territory of Smederevska Palanka. The energy germination and total germination were the highest in the first observed year and amounted to 63% and 88% for GB1, respectively. For GB2 the energy germination and total germination (2018) were 71% and 75%, respectively. A significant decline in total germination was determined in 2020. and amounted to 75% for GB1 and 67% for GB2( p<0.05). The lowest energy germination and total germination were obtained in the last observed year (2022) in both genotypes and statistically increased infection with Alternaria sp. and Fusarium sp. The presence of Alternaria sp. was detected for GB1 and GB2 in the range of 2-3% (2018); Fusarium sp. was 3%. In the last observed year, the presence of other fungi was determined, apropos a higher percentage of diseased seeds with Alternaria sp. and Fusarium sp. (5-6%). Other phytopathogenic fungi were detected in both genotypes: Aspergillus sp. (1-3%), Penicillium sp. (1-4%), Rhizopus sp. (1-3%) and Rhizoctonia solani (2-3%). The moisture was 8.5-10.9 for both genotypes and did not differ statistically between varieties (p>0.05). The impact of phytopathogenic fungi on green beans was reflected in the reduction of total germination, and therefore in seed quality and yield. The priority of future research is the application of biotreatments that will contribute to seed protection and improve total germination, and thus the yield in the field.

The cultivable endophytic fungal community of Scutellaria baicalensis: diversity and relevance to flavonoid production by the host

ABSTRACT Scutellaria baicalensis (SB), a traditional Chinese medicinal plant, is widely used because of its important pharmacological activities. However, the endophytic fungi that promote flavonoid accumulation in SB remain unclear. Therefore, we analyzed the endophytic fungal community of SB and screened the endophytic fungi that might promote flavonoid synthesis in SB. ITS1/ITS4Blast was used to identify the endophytic fungi in SB. In total, 687 strains were identified in 57 genera. The dominant genus in the leaves and stems was Alternaria and that in the roots was Fusarium. Alternaria was the dominant genus in SB collected from all sites and in wild and cultivated SB. Alpha diversity indexes indicated more abundant endophytic fungi in samples from Chengde, the genuine producing area of SB, than in those from other sites. Beta diversity index analysis indicated that SB plants with closer geographical relationships showed more similar endophytic fungal community profiles. Spearman correlation analysis revealed that baicalin, wogonoside, wogonin, and oroxylin A contents were significantly correlated with the relative abundance of Alternaria. Overall, the results indicate the importance of geographical factors in influencing the endophytic fungal community of SB and suggest that the presence of Alternaria spp. might contribute to flavonoid synthesis in SB.

Influence of genotype on representativeness of Alternaria sp. inside the seeds of winter wheat

Goal. To establish the influence of the genotype of winter wheat on the presence of Alternaria sp. in the seeds of winter wheat under different growing conditions, for different periods of time, among varieties from different original institutions of Ukrainian and foreign selection.
 Methods. Field — cultivation of wheat varieties in the Forest-Steppe of Ukraine; organizational — collection of seed samples; laboratory — analysis of the mycoflora of winter wheat seeds by biological method on the PGA, determination of Alternaria fungi on the environment of the PCA; analytical and mathematical — analysis of the obtained results and their statistical comparison.
 Results. The study of the influence of the variety on the isolation of Alternaria fungi for their cultivation in different years for the period from 2011 to 2020 and in different growing conditions proved the existence of a significant difference in their total amount and number of individual species, especially dominant. Differences were noted in the presence of Alternaria sp. inside the seeds grown in two climatic zones (Polissya and Forest-Steppe), on farms and in experimental fields. Three-year observation of the species of these fungi on two varieties from one originator showed their different isolation: both the presence of certain representatives and the number of their isolation. Analysis of 9 and 17 genotypes of wheat of Ukrainian and foreign selection during 2019 and 2020 also showed a different picture of the population of Alternaria fungi.
 Conclusions. Significant influence of genotype on the selection of Alternaria sp. was installed. Based on several years of studying the population of winter wheat seeds with Alternaria fungi, genotypes with a smaller presence were identified: in 2013—2015 — Gordovyta variety, in 2019—2020 — Emil, Pylypivka. It should be borne in mind that fewer alternative fungi reduce the presence of their mycotoxins, but increase the number of other fungi in the mycoflora, sometimes more dangerous.

MYCOBIOTA OF SOILS OF URBAN TERRITORIES WITH DIFFERENT LEVELS OF ANTHROPOGENIC LOAD

Anthropogenic forcing has a huge impact on the formation of the ecosystem of modern cities, including the composition of the mycobiota of the urban environment. The paper presents the results of mycological studies of soil samples taken in the city of Kazan in areas divided into recreational and transport functional areas with different levels of anthropogenic load. More than 60 species of fungi belonging to 15 genera, including 20 species common to soils in both zones were identified. Penicillium sp., Fusarium sp., Rhizomucor sp., Trichoderma viride were shown to dominate in undisturbed natural areas, and in soils of the urban environment there was much more often found the presence of Alternaria sp., Aspergillus sp., Candida sp., Rhizopus sp., Trichophyton sp. In areas with good natural light the percentage of samples with low contamination by fungi was established to be significantly higher than in shaded areas: 16.7% and 7.1% in the recreational area; and 12.5% and 0% in the transport zone correspondingly. Potentially pathogenic species of fungi were detected in 80% of samples of recreational and in 95% of samples of transport areas. Dark-colored species (including Aspergillus, Alternaria, etc.) were shown to be more common in soils of transport zone, and Trichophyton sp. and Scopulariopsis sp. - in soils of recreational zone. The evaluation of mycological hazard index allowed to estimate the condition of the soil of Kazan as satisfactory for 80% of sites of recreational and 65% - of the transport area. The average value of the mycological hazard index for recreational areas was 2.7 and for the transport areas - 4.2. Results indicate to regular mycological monitoring would be desirable for the normalization of the mycological environment, significantly reducing the risk of mycosis, mycotoxicosis and mycogenic allergies, and should help to ensure sanitary-epidemiological welfare of the population.

Presence of Alternaria in Scalp of Patients with Alopecia Areata: Triggering Factor or Coexistence?

Presence of Alternaria in Scalp of Patients with Alopecia Areata: Triggering Factor or Coexistence?

Alternaria Inhibits Double-Stranded RNA-Induced Cytokine Production through Toll-Like Receptor 3

Background: Fungi may be involved in asthma and chronic rhinosinusitis (CRS). Peripheral blood mononuclear cells from CRS patients produce interleukin (IL)-5, IL-13 and interferon (IFN)-γ in the presence of Alternaria. In addition, Alternaria produces potent Th2-like adjuvant effects in the airway. Therefore, we hypothesized that Alternaria may inhibit Th1-type defense mechanisms against virus infection. Methods: Dendritic cells (DCs) were generated from mouse bone marrow. The functional responses were assessed by expression of cell surface molecules by FACS (MHC class II, CD40, CD80, CD86 and OX40L). Production of IL-6, chemokine CXCL10 (IP-10), chemokine CXCL11 (I-TAC) and IFN-β was measured by ELISA. Toll-like receptor 3 (TLR3) mRNA and protein expression was detected by quantitative real-time PCR and Western blot. Results:Alternaria and polyinosinic-polycytidylic acid (poly I:C) enhanced cell surface expression of MHC class II, CD40, CD80, CD86 and OX40L, and IL-6 production in a concentration-dependent manner. However, Alternaria significantly inhibited production of IP-10, I-TAC and IFN-β, induced by viral double-stranded RNA (dsRNA) mimic poly I:C. TLR3 mRNA expression and protein production by poly I:C were significantly inhibited by Alternaria. These reactions are likely caused by heat-stable factor(s) in Alternaria extract with >100 kDa molecular mass. Conclusion: These findings suggest that the fungus Alternaria may inhibit production of IFN-β and other cytokines by DCs by suppressing TLR3 expression. These results indicate that Alternaria may inhibit host innate immunity against virus infection.

OCCURRENCE OF ALTERNARIA spp. IN THE SEEDS OF BASIL AND ITS PATHOGENICITY

Eighteen seed samples of basil, belonging to the cultivars most frequently grown in the Piedmont area for pesto production and obtained from farms affected by the disease in Piedmont during the fall of 2010 as well as from experimental lines of basil, were assayed for the presence of Alternaria spp., the causal agent of leaf spot of basil. Isolations were carried out by disinfected and not disinfected seeds. All eighteen tested samples resulted contaminated by Alternaria spp. and the frequency of isolation of Alternaria spp. colonies was higher in the case of not disinfected seeds for all samples tested. In the case of seeds belonging to experimental lines of basil, the frequency of isolation of Alternaria spp. was 1.18% from not disinfected seeds, and 0.43% from disinfected seeds. In the case of seeds belonging to commercial varieties of basil, Alternaria spp. was isolated respectively from 7.29% and 2.62% of not disinfected and disinfected seeds. When twenty-eight isolates of Alternaria spp. obtained from seeds of experimental lines of basil under development were tested for their virulence, 22 were able to infect basil leaves. Twenty of them, obtained from disinfected and not disinfected seeds, showed a good level of virulence, infecting more than 30% of leaves. One hundred eighty one isolates of Alternaria spp. strains were obtained from seeds of commercial varieties, of which 149 from not disinfected seeds and 32 from disinfected seeds. Out of 149 strains obtained from not disinfected seeds, 102 were virulent and 47 were not virulent. Only two isolates of Alternaria spp. out of 32 obtained by disinfected seeds were not virulent when tested on basil. This work provides evidence that Alternaria spp. the causal agent of leaf spot of basil, is seed-transmitted, which suggests that seeds may be important in disseminating the pathogen.

Alternaria in patients with allergic rhinitis.

Inhalation of fungal spores is shown to participate in the development of allergic rhinitis symptoms. In this study, relation between presence of Alternaria in the human nasal cavity and allergic rhinitis is assessed. In a case-control study, 58 allergic rhinitis patients were compared with a well-matched control group of fifty healthy volunteers for sensitization to Alternaria (by skin prick test) and detection of Alternaria in their nasal mucous by conventional methods (microscopy with Methylene Blue stain and culture in Sabourad dextrose agar). Severity of the disease was determined according to the ARIA classification. Pearson chi-square test was applied to compare the proportional difference between the study groups for detection of Alternaria in the nasal cavity, and sensitization to Alternaria. Relation between detection of Alternaria and allergic rhinitis was significant [OR = 18.18 (4.02-82.50)] In addition, sensitization to Alternaria showed a significant relation with the disease [OR = 2.8 (2.1-3.8)]. There was a significant relation between the presence of Alternaria in the nasal cavity and sensitization to Alternaria [OR = 10.4 (3.8-28.3)]. Both sensitization to Alternaria and presence of Alternaria in the nasal cavity did not have a significant relation with the severity of allergic rhinitis. This study suggests Alternaria as a major allergen that its presence in the nasal cavity and subsequent development of sensitization have significant role in the induction of allergic rhinitis.

Alternaria in patients with allergic rhinitis.

Inhalation of fungal spores is shown to participate in the development of allergic rhinitis symptoms. In this study, relation between presence of Alternaria in the human nasal cavity and allergic rhinitis is assessed. In a case-control study, 58 allergic rhinitis patients were compared with a well-matched control group of fifty healthy volunteers for sensitization to Alternaria (by skin prick test) and detection of Alternaria in their nasal mucous by conventional methods (microscopy with Methylene Blue stain and culture in Sabourad dextrose agar). Severity of the disease was determined according to the ARIA classification. Pearson chi-square test was applied to compare the proportional difference between the study groups for detection of Alternaria in the nasal cavity, and sensitization to Alternaria. Relation between detection of Alternaria and allergic rhinitis was significant [OR = 18.18 (4.02-82.50)] In addition, sensitization to Alternaria showed a significant relation with the disease [OR = 2.8 (2.1-3.8)]. There was a significant relation between the presence of Alternaria in the nasal cavity and sensitization to Alternaria [OR = 10.4 (3.8-28.3)]. Both sensitization to Alternaria and presence of Alternaria in the nasal cavity did not have a significant relation with the severity of allergic rhinitis. This study suggests Alternaria as a major allergen that its presence in the nasal cavity and subsequent development of sensitization have significant role in the induction of allergic rhinitis.

The presence of Alternaria spp. on the seed of Apiaceae plants and their influence on seed emergence

Considerable damping-off of the seedlings of several commercial Apiaceae plant species was observed in Serbia. The infection of a total of 48 seed samples of nine vegetable and spice plants with phytopathogenic Alternaria spp. was established using the deep-freeze-blotter method. Identification of Alternaria species was performed using both conventional methods and PCR. Four different plant-pathogenic Alternaria species were detected in Serbia: A. dauci, A. radicina, A. petroselini, and A. alternata, all of which caused reduction of carrot, parsley, parsnip, and celery seed emergence. Alternaria dauci, A. radicina, and A. petroselini were relatively more aggressive compared to A. alternata. Substantial seed infection levels and strong influence of Alternaria spp. on seed emergence indicated that production of Apiaceae seed needs to be improved in order to obtain pathogen-free seed.

First Report of Leaf Spot Caused by Alternaria alternata on Hydrangea macrophylla in Italy.

Hydrangea macrophylla is cultivated as an ornamental and also used in the landscape. During the fall of 2005, leaves and young stems on 12-month-old plants (cvs. Hanabi, Nigra, and Zaffiro) grown in pots in several gardens and commercial nurseries in the Piedmont (northern Italy) had extensive necrosis. In many cases, 4-mm-diameter spots on the upper side of the leaves were surrounded by a chlorotic halo, which turned progressively black. Lesions often coalesced into 3- to 8-cm-diameter necrotic areas. Initial necrosis developed mainly on the leaf margins and near the petioles. Severely affected plants were defoliated. Infected plants rarely died, but the presence of lesions reduced the aesthetic quality and subsequently the commercial value. The disease occurred on 30 to 50% of the plants. Leaf spots contained dark brown, multicellular, pear-shaped conidia. Conidia were 19.2 to 36.5 μm (average 26.3 μm) long and 7.7 to 11.5 μm (average 8.9 μm) wide, with 3 to 4 longitudinal cross walls and an average of 4.4 single cells. A fungus identified on the basis of its morphological characteristics as an Alternaria sp. was consistently isolated from symptomatic leaves onto potato dextrose agar. DNA was extracted from mycelium (Nucleospin Plant Kit, Macherey Nagel, Brockville, ON, Canada) and PCR was completed using Alt-for/Alt-rev primers (3), which amplified a part of the gene that encodes for the protein Alt a 1, the major allergen produced by the genus Alternaria. A 305-bp fragment was amplified, sequenced, and the sequence was subjected to BLASTn analysis (1), which confirmed that the isolate belonged to the genus Alternaria and to the alternata group (3). The nucleotide sequence has been deposited in GenBank (Accession No. EF446670). Pathogenicity tests were performed by spraying leaves of healthy potted H. macrophylla plants, cvs. Zaffiro (6-month-old) and Hanabi (12-month-old) with a spore suspension (105 conidia/ml). Plants sprayed with water only served as a control. Ten plants per cultivar were used for each treatment. Plants were covered with plastic bags for 5 days after inoculation and maintained at 20°C for an additional 7 days. Plants were transferred outdoors and kept at temperatures ranging from 19 to 25°C. The first foliar lesions developed on leaves 15 days after inoculation, whereas control plants remained healthy. Alternaria sp. was consistently reisolated from these lesions. The pathogenicity test was completed twice. The presence of Alternaria sp. on Hydrangea spp. was reported in the United States (2), whereas A. hortensiae was observed in Spain (4). To our knowledge, this is the first report of Alternaria sp. belonging to the alternata group infecting H. macrophylla in Italy. The disease is currently spreading in other Italian areas.

Relationship between airborne fungal spore presence and weather variables: Cladosporium and Alternaria

Abstract By means of regression analysis the Cladosporium and Alternaria spore counts for 1980–89 for Stockholm are explored and modelled at 6-hour intervals in order to find the relationship between spore presence and climate for the same time periods. Six different weather parameters are used. For Cladosporium daily mean temperature and daily precipitation seem to be consistently significant. The presence of Alternaria appears to be more complex. There is a tendency for Alternaria spore concentrations to increase with the daily precipitation, wind velocity and total cloud cover. The models are evaluated statistically. On the basis of 10 years of data from roof level in Stockholm the natural background load of Cladosporium and Alternaria as the most prevalent fungal aeroallergens is presented and discussed.