• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.316-320
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• 2017

Alternariol monomethyl ether (AME), a dibenzopyrone derivative, was isolated from Alternaria brassicae along with altertoxin II (ATX-II). The compounds were tested for the inhibitory activity of monoamine oxidase (MAO), which catalyzes neurotransmitting monoamines. AME was found to be a highly potent and selective inhibitor of human MAO-A with an $IC_{50}$ value of $1.71{\mu}M$; however, it was found to be ineffective for MAO-B inhibition. ATX-II was not effective for the inhibition of either MAO-A or MAO-B. The inhibition of MAO-A using AME was apparently instantaneous. MAO-A activity was almost completely recovered after the dilution of the inhibited enzyme with an excess amount of AME, suggesting AME is a reversible inhibitor. AME showed mixed inhibition for MAO-A in Lineweaver-Burk plots with a $K_i$ value of $0.34{\mu}M$. The findings of this study suggest that microbial metabolites and dibenzopyrone could be potent MAO inhibitors. In addition, AME could be a useful lead compound for developing reversible MAO-A inhibitors to treat depression, Parkinson's disease, and Alzheimer's disease.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.177-181
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• 2008

Mycotoxins produced by molds isolated from discolored sun-dried red pepper fruits were determined and the toxicity to animals was also tested by feeding mold-grown unpolished rice to rats. Among the mold species tested, only Alternaria alternata was toxic to experimental animals, while other mold species belonging to the genera of Colletotrichum, Diaporthe, Diaporthopsis, Botryosphereia, Aspergillus and Fusarium were not. Rats fed Alternaria-grown rice lost weight and died within two weeks of feeding period. Succumbed rats during the process of feeding study showed extreme cases of enlargements of stomach, small intestine and liver. Among the 17 Alternaria isolates, 8 species produced considerable amount of tenuazonic acid along with small amounts of other toxins including alternariol and monomethyl ether derivative of alternariol in both red pepper homogenate and unpolished rice. It is therefore advised that red pepper fruits infested by molds during the sun-drying process be discarded to avoid unnoticeable health hazards.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.151-157
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• 1995

국내에서 분리한 20종의 Alternaria 277개 균주를 사용하여 Alternaria 진균소독인 altenuene(ALT), altertoxin-I(ATX-I) 및 tenuazonic acid(TA)의 in vitro에서의 생성능과 그 분포를 조사하였다. 각 사용균주를 200g의 살균된 쌀배지에 접종하여 $25^{\circ}C$에서 3주간 배양하였다. Alternaria 배양체들을 methanol로 추출하고 용매분획과 TLC 및 HPLC분석을 통하여 순화하였다. A. alternata와 그와 형태적으로 유사한 A. kikuchiana, A. longipes 및 A. mail는 비록 종간 및 종내의 균주간에 생성량의 차이는 매우 다양하였지만 TA를 비롯한 5종의 진균독소를 모두 생성하였다. A sesami와 A. sesamicola는 4종의 진균독소(AOH, AME, ALT, ATX-I)를 생성하였고 A. cucumerina, A. dauci, A. macrospora, A. porri, A. solani, A. tagetica와 A. zinniae와 같은 대형분생포자와 긴 beak를 형성하는 7종의 Alternaria균들은 AOH와 AME만을 생성하였다. A. brassicicola, A. helianthi, A. panax, A. radicina 및 A. raphani등 5종의 Alternaria는 5종의 진균 독소를 모두 생성하지 않았다.

• Analytical Science and Technology
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• v.11 no.3
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• pp.206-212
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• 1998

The major mycotoxins were detected from peppers, onions and garlics infected postharvest pathogens, Alternaria, Penicillium and Fusarium. Analyses of the major mycotoxins were conducted using HPLC. Detected Alternaria mycotoxins per gram of infected postharvest peppers were alternariol (AOH) with amount ranged from small quantity to $440{\mu}g/g$, altenuene (ALT) with amount ranged from small quantity to $103{\mu}g/g$, tenuagonic acid (TeA) with amount ranged from 249 to $342{\mu}g/g$ and alternariol monomethyl ether (AME) with amount ranged from 206 to $294{\mu}g/g$. Penicillium toxins per gram of infected postharvest onions and garlics were citrinin with amount ranged from 2.8 to $18.4{\mu}g/g$, penicillun-G with amount ranged from no detection to $439.0{\mu}g/g$, penicillic acid with amount ranged from no detection to small quantity and patulin with amount ranged from no detection to small quantity. Fusarium toxins per gram of infected postharvest onions and garlics were fusaric acid with amount ranged from no detection to $553.6{\mu}g/g$. However, deoxyrivalenol and nivalenol were not detected from onins and garlics infected by Fusarium.

• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.1-8
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• 1995

Alternaria alternata and A. solani were identified from 130 Alternaria isolates obtained from red pepper fruits, and three species including A. alternata, A. sesami and A. sesamicola were detected from 150 isolates from sesame seeds. Among the 4 Alternaria species, A. alternata was the predominant fungus from both plants, having incidence of 95.4% in red pepper and 56.0% in sesame. Of the total 280 isolates, cultures on autoclaved rice of 75 isolates were tested for toxicity to 21-day-old virgin female rats. Out of 50 isolates of A. alternata, 17 were lethal to rats, inducing congestion and hemorrhage of stomach and intestine and kidney enlargement, and 8 caused lack of weight gain or weight loss. The other 25 isolates of A. alternat and all the isolates of A. sesami, A. sesamicola and A. solani, showed no significant indication of toxicity. Production of mycotoxins in the rice cultures of the above 75 isolates belonging to 4 species was analyzed. Alternaria cultures were extracted with methanol and purified by using solvent partition, thin-layer chromatography, and high performance liquid chromatography. Of the four species tested, all produced alternariol (AOH) and alternariol monomethyl ether (AME), three (A. alternata, A. sesami and A. sesamicola) produced alternuene (ALT) and altertoxin-I (ATX-I), and only A. alternata produced tenuazonic acid (TA). TA was produced by all of the highly toxic (lethal to rats) isolates of A. alternata, but not by any nontoxic isolates.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2004.05a
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• pp.224-228
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• 2004

2002년 8월부터 11월까지 전국 27개 지역에서 희나리 고추를 포함하고 있는 태양초 시료 40군을 수집하여 총 197주의 곰팡이를 분리하였다. 이 곰팡이들을 고체배지상에서의 번식속도, 분생포자의 모양 및 배양특성의 특성에 따라 6개의 group오로 나누었고 각 group에서 대표가 되는 30 균주를 임의로 선택하여 18S rRNA gene 염기서열을 분석하여 동정하였다. 희나리 곰팡이 중 에서 Colletotrichum 속 곰팡이가 66.5% (131/197)를 차지하여 가장 많이 분리되었고, 기타 Diaporthe phaseolorum var. sojae (28주, 14.2%), Alternaria alternata (17주, 8.6%), Botryosphaeria ribis (9주, 4.6%) Aspergillus oryzae var. oryzae (3주 1.5%) 및 Fusarium incarnatum (9주, 4.6%)이 동정되었다. 각 group에서 임의적으로 한 균주씩을 선택하여 현미에 배양한 뒤 쥐(rat)에 투여시험한 결과 A. alternata를 접종한 사료를 먹인 실험동물이 2주내에 모두 죽었으며 다른 곰팡이를 배양한 사료에는 특이한 영향이 없었다. A. alternata 곰팡이를 현미와 고추즙에 배양하여 주요 독소들을 분석한 결과 17주의 곰팡이 중 8주가 현미와 고추즙에서 많은 양 (현미: $488{\sim}1572\;{\mu}g/g$, 고추즙: $115{\sim}1050\;{\mu}g/g$)의 tenuazonic acid (TeA)를 생성하였다. alternariol(AOH)독소와 alternariol monomethyl ether (AME)는 현미에 배양했을 때만 흔적량 내지 소량씩이 관찰되었다. Alternaria 독소 중 altenuene는 현미와 고추즙 배지 모두에서 검출되지 않았다.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.13-13
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• 2018

Alternaria is a ubiquitous fungal genus, widely distributed in the environment and a range of different habitats. It includes both plant pathogenic and saprophytic species, which can affect crops in the field or cause post-harvest spoilage of plant fruits and kernels. Numerous Alternaria species cause damage to agricultural products including cereal grains, fruits and vegetables, and are responsible for severe economic losses worldwide. Most Alternaria species have the ability to produce a variety of secondary metabolites, which may play important roles in plant pathology as well as food quality and safety. Alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), tentoxin (TEN) and altenuene (ALT) are considered the main Alternaria compounds thought to pose a risk to human health. However, food-borne Alternaria species are able to produce many additional metabolites, whose toxicity has been tested incompletely or not tested at all. Both alternariols are mutagenic and their presence in cereal grain has been associated with high levels of human esophageal cancer in China. TeA exerts cytotoxic and phytotoxic properties, and is acutely toxic in different animal species, causing hemorrhages in several organs. The possible involvement of TA in the etiology of onyalai, a human hematological disorder occurring in Africa, has been suggested. Altertoxins (ALXs) have been found to be more potent mutagens and acutely toxic to mice than AOH and AME. Other metabolites, such as TEN, are reported to be phytotoxins, and their toxicity on animals has not been demonstrated up to now. Vegetable foods infected by Alternaria rot are obviously not suitable for consumption. Thus, whole fresh fruits are not believed to contribute significantly with Alternaria toxins to human exposure. However, processed vegetable products may introduce considerable amounts of these toxins to the human diet if decayed or moldy fruit is not removed before processing. The taxonomy of the genus is not well defined yet, which makes it difficult to establish an accurate relationship between the contaminant species and their associated mycotoxins. Great efforts have been made to organize taxa into subgeneric taxonomic levels, especially for the small-spored, food associated species, which are closely related and constitute the most relevant food pathogens from this genus. Several crops of agricultural value are susceptible to infection by different Alternaria species and can contribute to the entry of Alternaria mycotoxins in the food chain. The distribution of Alternaria species was studied in different commodities grown in Argentina. These food populations were characterized through a polyphasic approach, with special interest in their secondary metabolite profiles, to understand their full chemical potential. Alternaria species associated with tomato, bell pepper, blueberry, apples and wheat cultivated in Argentina showed a surprisingly high metabolomic and mycotoxigenic potential. The natural occurrence of Alternaria toxins in these foods was also investigated. The results here presented will provide background for discussion on regulations for Alternaria toxins in foods.