Aspergillus tubingensis | |
---|---|
(a) Colonies growing in Czapek medium for 7 days; (b) The yellowish colonies observed from the reverse side of the Czapek's agar; (c) Sporophore and spherical sporangium; (d) Conidia and sporangium with bilayer structure | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Fungi |
Division: | Ascomycota |
Class: | Eurotiomycetes |
Order: | Eurotiales |
Family: | Aspergillaceae |
Genus: | Aspergillus |
Species: | A. tubingensis |
Binomial name | |
Aspergillus tubingensis R.Mosseray 1934 | |
Synonyms | |
Aspergillus tubingensis is a darkly pigmented species of fungus in the genus Aspergillus section Nigri. [1] [2] It is often confused with Aspergillus niger due to their similar morphology and habitat. [1] A. tubingensis is often involved in food spoilage of fruits and wheat, and industrial fermentation. This species is a rare agent of opportunistic infection. [3]
Aspergillus tubingensis was first discovered by Raoul Mosseray in 1934. [4] The conidia are heavily roughened, 3-5 μm in diameter. [5] [6] Whitish to pink sclerotia ranging from 0.5 to 0.8 mm in diameter are often produced. A. tubingensis exists exclusively as an asexual fungus but is understood to be phylogenetically closely related to the other so-called black Aspergilli and sexual states in the genus Petromyces . The production of Ochratoxin A (OTA) was previously thought to be a variable character dependent on strain; [7] however, the production of OTA is thought to be a consistent feature with prior reports of variation arising from the inclusion of misidentified strains (e.g., A. niger) or inconsistencies in test conditions such as incubation time, temperature, and growth medium. [8] [9] Other extrolites produced by this fungus include: asperazine, pyranoigrin A, pyrophen, funalenone, and kotanins. [7] When cultured on creatine sucrose agar (CREA) culture medium, A. tubingensis demonstrates good acid production (strong yellow colour change) and a moderate growth rate. [6] A. tubingensis and A. niger have similar morphology and are difficult to distinguish without resorting to more advanced methods. One rapid test that is useful in distinguishing the two taxa, the Ehrlich reaction, queries the presence of indole. In this test, A. tubingensis is negative in contrast to A. niger which produces a positive result. Sequences of protein coding genes such as Calmodulin and β-tubulin also reliable differentiate the two taxa. [10] [11] The production of asperazine by A. tubingensis also separates this species from other morphologically similar Aspergilli. [7]
Aspergillus tubingensis exhibits high resistance to ultraviolet light and can grow in elevated temperatures [12] between 30–37 °C (86–99 °F), [13] with optimal growth between 21–36 °C (70–97 °F). [7] In the temperature range of 15–20 °C (59–68 °F), this species is able to produce the mycotoxin, ochratoxin A (OTA). [13] The fungus is tolerant of low pH and has a preference for environments of relatively low water activity. [12] Originally recognized from Chiang Mai, Thailand and China, [7] A. tubingensis is found worldwide in warm climate regions. It is often seen in indoor environments of Croatia and Turkey, with some appearances in the Netherlands, Hungary, Thailand, and Algeria. [14] This species is commonly isolated from soil and plant debris as well as agricultural crops such as grapes, cocoa, coffee, and cereal, [7] and as an agent of rot on apples, grapes, and cereals. [15]
Because of the paucity of mycotoxin production by A. tubingensis, it has been explored for use in biotechnology and industrial applications. [16] A. tubingensis is generally recognized as safe (GRAS) by the American food and drug administration (FDA). [1] This species is notable for the production enzymes such amylase, lipase, glucose oxidase, phytase, xylanase, acid phosphatase and xylosidase production. Amylase produced by A. tubingensis has potential use in the manufacture of bioethanol from distilled waste water and molasses residues. [17] The fungus is also able to produce commercially scalable organic acids including citric acid, ascorbic acid, and wood preservatives. [16] It is also capable of degrading polyurethane. [18]
In commercial baking, the use of glucose oxidase enzyme (GOD) enhances texture, size, and loaf form. A. tubingensis is part of the microbial consortium involved in the fermentation of Chinese pu'er tea, converting tea polyphenols into bioactive theobromins. [ unreliable source?] [19]
In crop production, soil amendation with A. tubingensis has been shown to enhance corn yield through its ability to dissolve phosphates into soil and reduce alkalinity in bauxite residues. [20] The tolerance of A. tubingensis to conditions of high pH enhance its survival in these applications. [20] A. tubingensis has been suggested as a biocontrol agent for the protection of tomato plants against the pathogenic fungus, Fusarium solani . [21] Deleterious effects of this fungus on crop plants are also known. For example, A. tubingensis has been documented in grape vineyards, alongside other black Aspergilli including A. carbonarius and A. niger. [22] In grape production, these Aspergilli have been implicated as important contributors to OTA in grape must. [23]
In 2018, they were investigated for their ability to decompose plastic such as polyurethane in weeks rather than decades. [24]
"The plastic-busting potential was discovered last year by a team of scientists from China and Pakistan, who sought to isolate the fungi that were degrading polyurethane at a waste disposal site in Islamabad. The fungi were identified as aspergillus tubingensis and the scientists observed how it broke down bonds between the different polymers in weeks, rather than the decades it can take plastic to naturally disintegrate." [24]
Fungal keratitis (corneal infection) can be caused by members of the black Aspergilli including A. tubingensis. [25] Aspergillus tubingensis has also been implicated in the infection of maxillary bone following a tooth extraction. [26]
Aspergillus niger is a mold classified within the Nigri section of the Aspergillus genus. The Aspergillus genus consists of common molds found throughout the environment within soil and water, on vegetation, in fecal matter, on decomposing matter, and suspended in the air. Species within this genus often grow quickly and can sporulate within a few days of germination. A combination of characteristics unique to A. niger makes the microbe invaluable to the production of many acids, proteins and bioactive compounds. Characteristics including extensive metabolic diversity, high production yield, secretion capability, and the ability to conduct post-translational modifications are responsible for A. niger's robust production of secondary metabolites. A. niger's capability to withstand extremely acidic conditions makes it especially important to the industrial production of citric acid.
Aspergillus ochraceus is a mold species in the genus Aspergillus known to produce the toxin ochratoxin A, one of the most abundant food-contaminating mycotoxins, and citrinin. It also produces the dihydroisocoumarin mellein. It is a filamentous fungus in nature and has characteristic biseriate conidiophores. Traditionally a soil fungus, has now began to adapt to varied ecological niches, like agricultural commodities, farmed animal and marine species. In humans and animals the consumption of this fungus produces chronic neurotoxic, immunosuppressive, genotoxic, carcinogenic and teratogenic effects. Its airborne spores are one of the potential causes of asthma in children and lung diseases in humans. The pig and chicken populations in the farms are the most affected by this fungus and its mycotoxins. Certain fungicides like mancozeb, copper oxychloride, and sulfur have inhibitory effects on the growth of this fungus and its mycotoxin producing capacities.
Aspergillus alliaceus is a species of fungus in the genus Aspergillus. It is from the Flavi section. It was first described scientifically by Charles Thom and Margaret Church in 1926. Its associated teleomorph is Petromyces alliaceus. It has yellow spores.
Aspergillus vadensis is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. vadensis belongs to the Nigri section. The species was first described in 2004. It has been found in air in Egypt. It produces the secondary metabolites asperazine and aurasperone A.
Aspergillus astellatus is a species of the genus of Aspergillus. It is from the Nidulantes section. Aspergillus astellatus produces Aflatoxin B1, Aflatoxin B2 and sterigmatocystin.
Aspergillus pulvericola is a species of fungus in the genus Aspergillus. It is from the Circumdati section. The species was first described in 2004. A. pulvericola produces ochratoxin A.
Aspergillus occultus is a species of fungus in the genus Aspergillus. It is from the Circumdati section. The species was first described in 2014. It has been reported to produce ochratoxin A and penicillic acid.
Aspergillus persii is a species of fungus in the genus Aspergillus which can cause onychomycosis. and otomycosis
Aspergillus fresenii is a species of fungus in the genus Aspergillus. Aspergillus fresenii produces ochratoxin A, ochratoxin B, ochratoxin C, aspochracins, mellamides, orthosporins, radarins, secopenitrems, sulphinines, xanthomegnins.
Aspergillus onikii is a species of fungus in the genus Aspergillus.
Aspergillus homomorphus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. homomorphus belongs to the Nigri section. The species was first described in 1995. It has been isolated from soil from the Dead Sea in Israel. The mycotoxin secalonic acid D has been reported from this fungus. In addition, it produces many exometabolites only found in this fungus.
Aspergillus indologenus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. indologenus belongs to the Nigri section. The species was first described in 2011. It was isolated from soil in India and found to produce insecticidal compounds okaramins A, B, H, and two types of indol-alkaloids which have not been structure elucidated.
Aspergillus lacticoffeatus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. lacticoffeatus belongs to the Nigri section. It was first described in 2004. It has been found on coffee beans in Venezuela and Indonesia, and is an effective producer of ochratoxin. It has an unfunctional PKS gene (pksA) for the production of black conidium pigment, which makes it the only species in the Nigri section which is brown and not black. It has been proposed that this species might not be a separate species but instead a mutated A. niger.
Aspergillus uvarum is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. uvarum belongs to the Nigri section. The species was first described in 2008. A. uvarum has been isolated from grapes in Europe. It has been shown to produce secalonic acid, which is common for other black aspergilli; and geodin, erdin, and dihydrogeodin, which are not produced by any other black aspergilli.
Aspergillus steynii is a species of fungus in the genus Aspergillus. It is from the Circumdati section. The species was first described in 2004. It has been shown to produce Ochratoxin A.
Aspergillus flocculosus is a species of fungus in the genus Aspergillus. It is from the Circumdati section. The species was first described in 2004. It has been isolated in Venezuela, Slovenia, Greece, Costa Rica, and Brazil.
Aspergillus pseudoelegans is a species of fungus in the genus Aspergillus. It is from the Circumdati section. The species was first described in 2004. It has been reported to produce asteltoxins and ochratoxin A.
Aspergillus westerdijkiae is a species of fungus in the genus Aspergillus. It is from the Circumdati section. The species was first described in 2004. It has been reported to produce penicillic acid, ochratoxin A, xanthomegnin, viomellein, and vioxanthin.
Aspergillus shendaweii is a species of fungus in the genus Aspergillus. It is from the Fumigati section. Several fungi from this section produce heat-resistant ascospores, and the isolates from this section are frequently obtained from locations where natural fires have previously occurred. The species was first described in 2014.
Aspergillus pallidofulvus is a species of fungus in the section Circumdati of the genus Aspergillus. It has been reported to produce aspergamide A, aspergamide B, notoamides, penicillic acid, mellein, 4-hydroxy mellein, xanthomegnin, viomellein, aspyrone, and neoaspergillic acid. Cycloechinulin has been reported from single isolates.
{{cite journal}}
: CS1 maint: DOI inactive as of January 2024 (link){{cite book}}
: CS1 maint: location missing publisher (link)