Analisi morfologica ed ecologica di differenti isolati del fungo agente di carie bianca <em>Ganoderma adspersum</em> (Schulzer) Donk (Agaricomycetes, Polyporales)
10.6092/issn.2531-7342/9092
In questo lavoro sono state valutate le caratteristiche morfologiche e di crescita di differenti isolati del fungo medicinale Ganoderma adspersum (Agaricomicota, Poliporales). Le colture pure sono state isolate da basidiomi provenienti da Armenia Georgia e Iran e fatte sviluppare su estratto di malto agarizzato (MEA), agar patata (PDA) e in coltura liquida a diverse temperature (25, 30, 35, 38 °C) per 14 giorni. Sono state quindi descritte le caratteristiche specifiche macro e microscopiche dei miceli quali il colore dapprima bianco cotonoso, poi giallo limone-crema coriaceo, con unioni a fibbia di forma rotonda, rigonfiamenti ifali tipo clamidospore, cellule cuticolari brunastre e numerosi cristalli tetraedrici. Inoltre, è stata osservata la formazione di pellet piccoli, densi e lisci, nonché rigonfiamenti ifali durante la crescita in mezzo liquido. La temperatura di crescita più favorevole per lo sviluppo dei ceppi G. adspersum studiati è stata di 25-30 °C. Le caratteristiche culturali rivelate sono un utile strumento per l'identificazione e il controllo della purezza delle colture miceliali di questa specie fungina durante le diverse fasi di coltivazione in vitro del micelio.
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Italian Journal of Mycology
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Morphological and ecological screening of different collections of medicinal white-rot bracket fungus <em>Ganoderma adspersum</em> (Schulzer) Donk (Agaricomycetes, Polyporales)
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Ital J Mycol
Alessandra Zambonelli
2019/03/01
10.6092/issn.2531-7342/9092
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Wang B, Hua JA (1991) Cultural atlas of some Ganoderma cultures. Food Industry Research and Development Institute, Hsinchu.
Morphological and ecological screening of different collections of medicinal white-rot bracket fungus <em>Ganoderma adspersum</em> (Schulzer) Donk (Agaricomycetes, Polyporales)
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Badalyan et al.                               Italian Journal of Mycology 48:1-15 (2019)
DOI: https://doi.org/10.6092/issn.2531-7342/9092
_________________________________________________________________________
Morphological and ecological screening of different
collections of medicinal white-rot bracket fungus Ganoderma
adspersum (Schulzer) Donk (Agaricomycetes, Polyporales)
____________________________________________________
Susanna M. Badalyan1, Narine G. Gharibyan1, Mirco Iotti2, Alessandra
                           Zambonelli3


1
  Laboratory of Fungal Biology and Biotechnology, Institute of Pharmacy, Department of
Biomedicine, Yerevan State University, 1 A. Manoogian St.,0025, Yerevan, Armenia
2
  Department of Health, Life and Environmental Sciences, University of L’Aquila, via
Vetoio, Coppito 1, 67100 L’Aquila, Italy
3
  Department of Agricultural and Food Sciences, University of Bologna, via Fanin 44,
40127 Bologna, Italy

       Corresponding author e-mail: s.badalyan@ysu.am


Abstract
The screening of morphological and growth characteristics of mycelial collections of
medicinal bracket fungus Ganoderma adspersum (Agaricomycetes, Polyporales) of
different geographical origins (Armenia, Georgia, Iran) on malt-extract agar (MEA) and
potato-dextrose agar (PDA) media for 6 days, as well as in submerged culture (malt-extract,
ME, 200 rt min) for 14 days at different temperature (25, 30, 35, 38 °C) was performed.
Species-specific mycelial macro- and micromorphological characteristics, such as white,
cottony-felt, later chamois, leathery, creamy-lemon-yellowish fast-growing colonies, round-
shaped hyphal clamps, hyaline, round-shaped, smooth chlamydospore-like swellings and
brownish cuticular cells, numerous tetrahedral crystals were described in agar and
submerged cultures. The formation of small, dense and smooth pellets, as well as hyphal
swellings during submerged growth was observed. The favorable growth temperature for
studied collections of G. adspersum was 25-30 °C. The revealed cultural characteristics will
be used for taxonomic identification and quality control of mycelial cultures during their
biotechnological cultivation.

Key words: Ganoderma adspersum; mycelium; morphological characteristics; growth rate;
chlamydospores; cuticular cells; pellets




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ISSN 2531-7342
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Badalyan et al.                    Italian Journal of Mycology 48:1-15 (2019)
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Introduction

Currently, an interest towards the study of genetic resources of medicinal
polyporoid fungi (class Agaricomycetes, order Polyporales), as valuable
biological resources with high exploratory potential, including the
production of nutraceuticals, nutriceuticals, pharmaceuticals, and
cosmeceuticals is increasing (Badalyan and Gharibyan, 2015, 2016;
Badalyan et al., 2015; Saltarelli et al., 2015; Taofiq et al., 2016, 2017;
Gargano et al., 2017; Badalyan and Zambonelli, 2019).
    The white-rot cosmopolitan polypores of the genus Ganoderma Karst.
(family Ganodermataceae) include more than 250 species (Ryvarden, 1991).
Among these fungi, G. applanatum (Pers.) Pat., G. lucidum (Curtis) P.
Karst., G. resinaceum Boud., and G. tsugae Murrill [=Polyporus tsugae
(Murrill) Overh.] are medicinally important, particularly in the Asian
continent and widely used in traditional medicine for the therapy of chronic
diseases for over 2000 years (Paterson, 2006). They are considered
producers of several bioactive molecules (terpenoids, polysaccharides,
alkaloids, phenolics, etc.) with different therapeutic effects (antimicrobial,
antioxidant, antitumor, immunomodulatory, etc.) (Gao et al., 2003; Boh et
al., 2004; Teplyakova and Kosogova, 2016; Gargano et al., 2017; Kües and
Badalyan, 2017; Badalyan et al., 2019; Badalyan and Zambonelli, 2019).
    Ganoderma spp. develop laccate and non-laccate basidiomata. They are
distributed over a broad eco-geographical range and have been reported on
more than 150 host species including deciduous and conifer trees
(Adaskaveg and Gilbertson, 1986; Singh et al., 2016). The low sequence
variation observed in the LSU ribosomal gene suggested that the
Ganoderma genus has recently diverged (Moncalvo et al., 1995) and, due to
the high range of variability of macro- and micro-morphological
characteristics of basidiomata several synonymous names have been created
and that makes this genus the most difficult to classify among the polypores
(Moncalvo et al., 1995; Moncalvo, 2005; Tsivileva et al., 2016). Therefore,
for correct identification of Ganoderma spp. without having to resort to
molecular testing, taxonomically valuable morphological and growth
characteristics of mycelia are required particularly during their
biotechnological cultivation (Badalyan and Sakeyan, 2004; Badalyan et al.,
2012a; Clémançon, 2012; Badalyan and Kües, 2015; Badalyan et al., 2015;
Kües et al., 2016).
    Cultural studies of Ganoderma spp. were previously conducted by
several researchers. However, available scientific reports on systematic and
comparative morphological observations of mycelia, asexual sporulation in
the life cycle and other characteristics, as well as evaluation of their

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taxonomic value are limited (Nobles, 1965; Stalpers, 1978; Hseu, 1990;
Wang and Hua, 1991; Hong and Jung, 2004; Jayasinghe et al., 2008;
Bukhalo et al., 2009; Jo et al., 2009; Mohanty et al., 2011).
   The presence of chlamydospores or chlamydospore-like swellings is a
species-specific characteristic of the Ganoderma species (Adaskaveg and
Gilbertson, 1989; Bukhalo et al., 2009; Kües et al., 2016; Tsivileva et al.,
2016). It has been shown that host relationships, production of terminal and
intercalary chlamydospores, the range of average growth rate (from 2.1 mm
d-1 to 7.8 mm d-1) and thermophily (from 20 °C to 50 °C) of different
Ganoderma spp. are useful taxonomic criteria to distinguish their mycelial
cultures and reveal phylogenetic relationships among species (Adaskaveg
and Gilbertson, 1986, 1989; Moncalvo et al., 1995; Badalyan et al., 2012a-
b; Tsivileva et al., 2016). A remarkable correlation between mycelial
characters was particularly found: fast-growing cultures are thermophilic
and produce numerous ovoid chlamydospores, while slow growing cultures
are not thermophilic and do not produce chlamydospores (Moncalvo et al.,
1995). It was revealed that mycelial characters are less polymorphic than
morphological characters of the basidiomata between recently diverged taxa
(Moncalvo et al., 1995). Therefore, culture characters are useful in
distinguishing between Ganoderma taxa.
   In general, the relatively low temperature of 21°C was not appropriate for
normal growth of Ganoderma strains, however there are several species (G.
meredithiae Adask. & Gilb., G. oregonense Murrill, G. zonatum Murrill)
which prefer an optimal temperature range from 20 °C to 25 °C (Adaskaveg
and Gilbertson, 1986; Badalyan et al., 2015; Tsivileva et al., 2016; Badalyan
and Gharibyan, 2017a).
   The laccate Ganoderma species G. lucidum and G. tsugae grows on malt-
extract agar (MEA) with the average growth rate of 7.8 mm d-1 at optimum
temperature range 30-34 °C and 2.1 mm d-1 at 20-25 °C. Ganoderma
lucidum formed chlamydospores, while G. tsugae did not (Adaskaveg and
Gilbertson, 1986). There are other reports that G. lucidum strains grow with
average growth rate 10.6 mm d-1 at temperature optimum 22-26 °C (Szedlay
et al., 1996) or 9.1 mm d-1 at 26-30 °C (Wang and Hua, 1991) on MEA.
Other laccate species G. zonatum, G. meredithiae, and G. oregonense prefer
optimum temperature range of 20-25 °C and do not produce
chlamydospores. However, formation of staghorn hyphae, thin- and thick-
walled cuticular cells in G. zonatum, G. meredithiae, and G. oregonense
was reported. Previously undescribed hyphal rosettes were also typical
mycelial structures in G. zonatum (Adaskaveg and Gilbertson, 1986).
Thermophilic laccate species Ganoderma colossus (Fr.) C.F. Baker prefers
optimal growth temperature range 35-40 oC and at 37 oC showed growth

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rate 15.0 ± 0.7 mm d-1 (Tsivileva et al., 2016). Ganoderma colossus grows
slowly at 45 °C and survives exposure to 50 °C. It formed spherical thick-
walled globular up to 20 µm in diameter rough chlamydospores (Adaskaveg
and Gilbertson, 1986; Tsivileva et al., 2016).
   For non-laccate species G. applanatum [=G. applanatum f. australe (Fr.)
Bourdot & Galzin] the optimum temperatures ranging from 25-30 °C were
found to be suitable for the mycelial growth on potato dextrose agar (PDA).
It was revealed that the colonies of G. applanatum are denser on PDA (8.8
mm d-1), compared to MEA (7.5 mm d-1) (Jeong et al., 2009; Jo et al., 2009;
Luangharn et al., 2017). Several studies have reported the optimal pH range
for mycelial growth of various Ganoderma species to be pH 5-9 (Jayasinghe
et al., 2008; Jo et al., 2009). The fastest mycelial growth of G. applanatum
was observed in alkaline media of pH 7-8 (Luangharn et al., 2017).
   Previous works (Badalyan et al., 2012a-b, 2015) have shown that the
temperature range for optimal mycelial growth for laccate (G. lucidum and
G. resinaceum) and not laccate (G. adspersum, G. applanatum)
species/strains was 25-30 °C. At 35 °C, the growth of G. adspersum and G.
resinaceum was suppressed and observed mainly on inocula while G.
applanatum and G. lucidum did not grow at all. At 38 °C, only G.
resinaceum showed poor growth.
   Ganoderma adspersum (Schulzer) Donk (=Ganoderma europaeum
Steyaert) form non-laccate basidiomata, similar to G. applanatum and
Ganoderma gibbosum (Blume & T. Nees) Pat. with other common
morphological characteristics which often lead to misidentification of these
species (Steyaert, 1980; Adaskaveg and Gilbertson, 1986, 1989; Ryvarden
and Gilbertson, 1993). In Armenia, G. adspersum was originally collected
in 2002, on ash tree (Fraxinus sp.) in the city park of Yerevan and
morphologically identified as G. applanatum. Using DNA barcoding,
mycelium isolated from this basidioma was taxonomically verified as G.
adspersum (Badalyan et al., 2012b). The basidiomata of G. adspersum were
recollected in Armenia from 2005-2015, particularly in Yerevan and
Hankavan, as well as in the village Berdavan on different wood hosts
(Morus alba L., Acacia sp., Fraxinus sp., Quercus sp. and Fagus sp.)
(Badalyan et al., 2012b; 2015; Badalyan and Gharibyan, 2017a). Several
medicinal properties, such as antifungal activity, have been reported in the
mycelia of G. adspersum (Badalyan et al., 2012a; Badalyan and Gharibyan,
2015, 2017b). In this paper, the study of morphological, ecological and
growth characteristics of ten different genotyped mycelial collections of G.
adspersum is presented.



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Materials and Methods

Ganoderma samples were collected in Armenia during 2002–2015 on
Acacia sp., Fraxinus sp., M. alba and Quercus sp. trees, in Iran on
deciduous tree in 2008 and in Georgia on Laurus camphora L. tree in 2013
(Table 1, Fig. 1). Traditional taxonomic keys were used for morphological
identification of basidiomata (Phillips, 1981; Ryvarden, 1991). Dikaryotic
cultures were isolated from collected basidiomata by tissue method
(Bukhalo, 1988) and maintained on MEA or in distilled water at 5 °C in
tubes. Mycelial collections were genetically identified and verified using
nuclear ITS–rDNA sequence data by previously reported methods
(Badalyan et al., 2012b, 2015) (Table 1).

Table 1. The studied collections of G. adspersum
Catalogue Strain       Substrate             Origin and date of culture GenBank
number                                       isolation                  accession
                                                                        number*
 5501       Ga-1**     Fraxinus sp.          Armenia, Yerevan, 2002       JN588580
 5502       Ga-2-1     Morus alba            Armenia, Yerevan, 2005       JN588583
 5503       Ga-2-2     M. alba               Armenia, Yerevan, 2005       JN588581
 5504       Ga-2-3     M. alba               Armenia, Yerevan, 2005       JN588582
 5506       Ga-3       Acacia sp.            Armenia, Yerevan, 2010       JN588585
 5507       Ga-9       Fraxinus sp.          Armenia, Yerevan, 2011       not available
 5509       Gad-6      Quercus sp.           Armenia, Tavush province,    KP941436
                                             village Berdavan, 2013
 5517       Gad-03     Laurus camphora       Georgia, Batumi, 2013        KP941440
 5518       Gad-VII    L. camphora           Georgia, Batumi, 2013        KP941441
 5520       1016       Deciduous tree        Iran, Zagh Marz, Behshahr,   KP941442
                                             2008
*Published by Badalyan et al., 2012b, 2015
**The catalogue numbers and accession numbers of strains correspond to strain names with
slash published in the catalogue (Badalyan, Gharibyan, 2017a)




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Fig. 1. Fruiting body of G. adspersum collected in 2002 in Yerevan (Armenia) on Fraxinus
sp. (a); basidiospores (b)

   The morphology and growth rate of mycelia were studied after
inoculation of 5 mm3 inocula (three replicates per strains) into the center of
90-mm Petri dishes at different temperatures (25, 30, 35, and 38 °C) using
1.5% MEA and PDA media (pH 6.0) for 6 days. They were also studied in
submerged culture (pH 6.0, 200 rt min-1, 25 °C) using Erlenmeyer flasks
(250 ml, 5 inocula each) for 14 days of incubation under dark conditions.
Micro- and macromorphological observation of mycelial colonies and
pellets, anamorphs, as well as determination of average growth rates (GRavr)
were realized by previously reported methods (Badalyan et al., 2012b,
2015). The preparations were examined under the microscope Omano
OM157-T Trinocular (USA) with software program (OC View 7, ver. 7.1)
using 15×40 ocular/objective, as well as Axioplan-2 imaging microscope
(Zeiss, Germany) using 10×40 ocular/objective. The photos were taken by
OptixCam summit OCS 1.3MP and Colour View II Mega Pixel digital
microscope cameras using analySIS® software (Münster, Germany).
   The texture and pigmentation of colonies were described by Stalpers’
scale before covering the Petri dish (Stalpers, 1978). The sizes of
chlamydospore-like hyphal swellings, cuticular cells and crystals were
measured by 10 replicates. The fruiting ability of mycelia was evaluated
transferring the Petri dishes, after 30 days of incubation in the dark, into
humid containers at room temperature 23±2 °C under day/night regime.
   The statistical analysis was performed by SLOPE algorithm (Microsoft
Excel; Microsoft Corp., Redmond, WA, USA) and expressed as mean ±
S.D.
   The cultures are preserved in the Fungal Culture Collection of the
Laboratory of Fungal Biology and Biotechnology, Yerevan State University
(FCC-YSU) under the catalogue numbers (Badalyan and Gharibyan,


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2017a), as well as in the Culture Collection (CMI-UNIBO) of the
department of Agricultural and Food Sciences, University of Bologna.

Results and discussion

Macromorphological characteristics
The colonies of G. adspersum were initially white, cottony-felt, later
chamois, leathery, creamy-lemon-yellowish, with suppressed and smooth
margin (Fig. 2). The agar is bleached but locally yellowish, in some places
light brown. In submerged culture, G. adspersum forms small, dense,
smooth and leathery pellets (Fig. 3). The development of fruiting bodies
with mature basidiospores was only observed in Armenian strains Ga-9 and
Ga-2-2.




Fig. 2. Mycelial colonies of G. adspersum str. Ga-2-2 grown on MEA and PDA for 6 days
at 25 °C (a,d), 30 °C (b,e) and 35 °C (c,f)

Mycelial growth rates
Depending on media composition and temperature, the variability of
mycelial GRavr indicators in tested collections was detected. However, no
significant difference was found between tested media for cultivation of G.
adspersum strains although some strains grow better on PDA (Table 2).
   At 25 °C, the cultures grew relatively slower on MEA (GRavr = 3.4-5.1
mm d-1) than PDA (GRavr = 3.5-6.0 mm d-1) (Table 2; Fig. 2a,b,d,e). The
GRavr indicators were higher at 30 °C on MEA (4.0-6.8 mm d-1), particularly


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in Georgian strains Gad-03 (6.3 mm d-1) and Gad-VII (6.8 mm d-1), than
PDA (3.0-5.5 mm d-1). At 35 °C, only six strains isolated from ash,
mulberry and acacia trees showed slow growth on MEA (GRavr = 1.3-2.1
mm d-1) and PDA (GRavr = 1.9-2.8 mm d-1), while suppressed growth was
observed only for on inocula of Gad-6, Gad-03, Gad-VII and 1016 strains
isolated from oak, camphor and deciduous trees, respectively (Table 2; Fig.
2c,f). At 38 °C, no mycelial was observed in tested strains. Thus, optimal
growth temperature range in collections of G. adspersum was 25-30 °C. A
higher temperature above 30 °C suppressed mycelial growth of G.
adspersum, similar to morphologically and phylogenetically close species
G. applanatum (Moncalvo, 2000; Jargalmaa et al., 2017).




Fig. 3. Mycelial pellets formed by G. adspersum strains after 14 days of growth in malt-
extract medium (pH 6.0, 200 rt min-1) at room temperature: Ga-1 (a), Ga-2-3 (b), Gad-03
(c) and Gad-6 (d)

Micromorphological characteristics
The presence and form of hyphal clamps, asexual spores, including
chlamydospores are valuable taxonomic criteria in Agaricomycetes fungi
(Badalyan and Sakeyan, 2004; Badalyan et al., 2015; Badalyan and Kües,
2015; Kües et al., 2016).
   Staghorn hyphae, thin- and thick-walled round-shaped hyaline or
brownish cuticular cells organized from generative hyphae, hyphal rosettes
and wrinkled hyphae were previously described in Ganoderma species
(Nobles, 1965; Stalpers, 1978; Adaskaveg and Gilbertson, 1986, 1989;
Bukhalo et al., 2009; Tsivileva et al., 2016).
   In the advancing zone of colony, the hyphae of G. adspersum are hyaline
with single, one-sided clamp-connections at almost each septum (Fig. 4a,b).
Formation of coralloid-like hyphae was also typical for G. adspersum (Fig.
4c). Oidia and blastoconidia were not observed, while the round-shaped,
double-walled, smooth, thick-walled hyaline chlamydospore-like swellings
(3.49-5.60 x 3.13-6.22 µm) (Fig. 4e,f,g), and brownish spherical cuticular
cells (4.37-8.61 x 4.31-8.96 µm) (Fig. 4j,k) were abundant in the aging agar

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culture of G. adspersum. Cuticular cells were previously reported in
Ganoderma cultures, including G. adspersum and G. lucidum (Nobles,
1965; Stalpers, 1978; Badalyan and Kües, 2015; Tsivileva et al., 2016).

Table 2. The average growth rate (GRavr, mm d-1) of G. adspersum strains at different
culture conditions on the 6th day of growth
Strain      Temperature

            25 oC                     30 oC                  35 oC                  38 oC
            MEA            PDA        MEA          PDA       MEA        PDA         MEA     PDA
Ga-1        5.1±0.8*       6.0±1.4    5.2±0.2      3.9±0.6   1.3±0.1    2.8±0.1     NG      NG
Ga-2-1      4.6±0.8        5.5±1.2    5.4±0.7      5.0±1.7   1.8±0.1    2.4±0.1     NG      NG
Ga-2-2      4.8±0.8        5.4±1.1    5.8±0.5      5.5±1.2   2.1±0.1    2.5±0.1     NG      NG
Ga-2-3      4.3±0.6        5.0±0.9    5.4±0.4      4.1±0.9   1.8±0.1    1.9±0.3     NG      NG
Ga-3        3.4±0.6        5.9±1.1    4.0±0.3      4.6±1.0   2.0±0.1    2.2±0.3     NG      NG
Ga-9        4.6±0.8        4.6±0.9    5.0±0.2      4.5±0.9   1.5±0.1    2.2±0.3     NG      NG
Gad-6       4.0±0.7        3.6±0.3    4.5±0.6      3.0±1.0   GI         GI          NG      NG
Gad-03      4.3±1.0        4.0±0.5    6.3±0.9      3.5±0.5   GI         GI          NG      NG
Gad-VII     4.7±0.9        3.7±0.7    6.8±1.1      3.5±0.7   GI         GI          NG      NG
1016        3.8±0.7        3.5±0.5    4.7±0.9      4.0±1.0   GI         GI          NG      NG
Notes: (MEA) - malt extract agar, (PDA) – potato-dextrose agar; (GI) – growth on
inoculum; (NG) – not growth. (*) - Mean of 6 replicates.

Table 3. Sizes (µm) of cultural structures in studied collections of G. adspersum
Microstructure                    Length           Average          Wide         Average
                                                   Length                        Wide
Cuticular cells                   4.37-8.61        6.42±1.51        4.31-8.96    6.10±1.15
Hyphal swellings in agar             3.49-5.60        4.69±0.82        3.13-6.22     4.91±1.09
culture
Hyphal swellings in                  10.23-21.22      13.40±3.95       7.86-10.38    9.50±0.99
submerged culture
Crystals in agar culture             5.33-10.46       7.62±1.62        4.96-9.41     6.87±1.54
Crystals in submerged culture        6.31-18.39       10.38±6.94       5.72-17.28    9.64±6.62
Note: (*) - Mean of 10 replicates ± SD

  The salt crystals observed in mushroom cultures are usually calcium
oxalate crystals, which mainly formed on hyphae under different culture

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conditions. They are a relatively stable characteristic of fungal cultures since
the morphology and abundance of crystals may vary in different
species/strains. Numerous tetrahedral crystals in agar (5.33-10.46 x 4.96-
9.41 µm) and liquid (6.31-18.39 x 5.72-17.28 µm) cultures of G. adspersum
were observed (Fig. 4d,i). In submerged culture vacuolated hyphae with
clamps and chlamydospore-like swellings (10.23-21.22 x 7.86-10.38 µm)
were abundantly observed in G. adspersum (Table 3; Fig. 4h,l).




Fig. 4. Mycelial microstructures in G. adspersum on agar media: (a,b) hyphal clamps; (c)
coralloid hyphae in str. Ga-2-3; (d) crystals in str. Ga-1; (e,f,g) chlamydospore-like
swellings in str. Ga-9; (j,k) cuticular cells in str. 1016; (l) swelled and (h) vacuolated
hyphae in str. Gad-6; (i) crystal in str. Ga-3 in submerged culture. Size bar 10 µm

Conclusion

The revealed taxonomically valuable mycelial characteristics of G.
adspersum (colony texture, pigmentation, growth rate, presence and form of
hyphal clamps, coralloid hyphae, chlamydospore-like swellings and/or
cuticular cells, optimal growth temperature) will assist in the proper
taxonomic identification of cultures, control their quality and optimal
growth conditions during their biotechnological cultivation.




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Acknowledgements

The study was realized in collaboration between Yerevan State University, Armenia and
University of Bologna, Italy, as well as with the support of SCS RA research grants (15RF-
064; 18T‐1F115). SMB thanks the DAAD for supporting microscopic work at the
University of Göttingen, Dr. A. Borhani (Iran) for providing strain 1016 and T. Shahbazyan
for technical assistance.

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