Ganoderma Strains Research Articles

Enhancing high-efficiency breeding and microbial microdroplet cultivation techniques for Ganoderma lucidum.

Ganoderma lucidum is known for its bioactive compounds, such as polysaccharides and triterpenoids, which are crucial in food and medicine. However, liquid fermentation encounters challenges in terms of strain differentiation and stability. In this research, we employed atmospheric room temperature plasma mutation and a microbial microdroplet culture system to identify strains with enhanced biomass and triterpenoid production. The three mutant strains, YB05, YB09, and YB18, exhibited accelerated growth rates and antagonized the initial strain G0023 more effectively than the controls. Notably, YB18 displayed the fastest growth, with a 17.25% increase in colony radius. Shake flask cultivation demonstrated that, compared with the initial strain, YB05 and YB18 had 26.33% and 17.85% greater biomass, respectively. Moreover, the triterpenoid production of YB05 and YB18 surpassed that of the control by 32.10% and 15.72%, respectively, as confirmed by colorimetric detection. Importantly, these mutant strains remained stable for five generations. This study revealed a comprehensive screening system utilizing atmospheric pressure, room temperature plasma mutation technology and microbial droplet cultivation. This innovative approach offers a promising pathway for obtaining advantageous Ganoderma strains for liquid fermentation. The methodology of atmospheric room temperature plasma mutation and microbial microdroplet culture systems is detailed for better comprehension.

Comparative Analysis of Agronomic Traits, Yield, and Effective Components of Main Cultivated Ganoderma Mushrooms (Agaricomycetes) in China.

To assess the strain resources and address production challenges in Ganoderma cultivation. 150 Ganoderma strains were collected from 13 provinces in China. A comparative analysis of agronomic traits and effective components was conducted. Among the 150 strains, key agronomic traits measured were: average stipe diameter (15.92 mm), average stipe length (37.46 mm), average cap horizontal diameter (94.97 mm), average cap vertical diameter (64.21 mm), average cap thickness (15.22 mm), and average fruiting body weight (14.30 g). Based on these agronomic traits, four promising strains, namely, L08, L12, Z21, and Z39, were recommended for further cultivation and breeding. The average crude polysaccharide content ranged from 0.048% to 0.977%, and triterpenoids ranged from 0.804% to 2.010%. In addition, 73 triterpenoid compounds were identified, constituting 47.1% of the total compounds. Using a distance discrimination method, the types, and relative contents of triterpenoid compounds in 150 Ganoderma strains were classified, achieving 98% accuracy in G. lingzhi identification. The 16 triterpenoid components used for G. lingzhi identification included oleanolic acid, ursolic acid, 3β-acetoxyergosta-7,22-dien-5α-ol, ganoderic acid DM, ganoderiol B, ganorderol A, ganoderic acid GS-1, tsugaric acid A, ganoderic acid GS-2, ganoderenic acid D, ganoderic acid Mf, ganoderic acid A, ganoderic acid K, ganoderic acid V, ganoderic acid G, and leucocontextin J. This study provides valuable insights for exploring and utilizing Ganoderma resources and for the development of new varieties.

Comprehensive analysis of codon bias in 13 Ganoderma mitochondrial genomes.

Codon usage bias is a prevalent phenomenon observed across various species and genes. However, the specific attributes of codon usage in the mitochondrial genome of Ganoderma species remain unknown. In this study, we investigated the codon bias of 12 mitochondrial core protein-coding genes (PCGs) in 9 Ganoderma species, including 13 Ganoderma strains. The codons of all Ganoderma strains showed a preference for ending in A/T. Additionally, correlations between codon base composition and the codon adaptation index (CAI), codon bias index (CBI) and frequency of optimal codons (FOP) were identified, demonstrating the impact of base composition on codon bias. Various base bias indicators were found to vary between or within Ganoderma strains, including GC3s, the CAI, the CBI, and the FOP. The results also revealed that the mitochondrial core PCGs of Ganoderma have an average effective number of codons (ENC) lower than 35, indicating strong bias toward certain codons. Evidence from neutrality plot and PR2-bias plot analysis indicates that natural selection is a major factor affecting codon bias in Ganoderma. Additionally, 11 to 22 optimal codons (ΔRSCU>0.08 and RSCU>1) were identified in 13 Ganoderma strains, with GCA, AUC, and UUC being the most widely used optimal codons in Ganoderma. By analyzing the combined mitochondrial sequences and relative synonymous codon usage (RSCU) values, the genetic relationships between or within Ganoderma strains were determined, indicating variations between them. Nevertheless, RSCU-based analysis illustrated the intra- and interspecies relationships of certain Ganoderma species. This study deepens our insight into the synonymous codon usage characteristics, genetics, and evolution of this important fungal group.

Antiproliferative and antibacterial activity of extracts of Ganoderma strains grown in vitro.

In this bioprospecting study the biological activities of extracts of the in vitro culture of Ganoderma Mexican strains were evaluated. The extracts were tested by the Sulforhodamine B staining method for antiproliferative activity and the plate microdilution method for antibacterial activity. Extracts that proved bioactive in these two activities, the antioxidant activity (Galvinoxyl, ABTS, and DPPH) and total phenolic contents (Folin-Ciocalteu) were additionally determined, as well as acute toxicity (Artemia franciscana). In the antiproliferative activity Ganoderma curtisii strain (GH-16-015) obtained a remarkable value of GI50 ≤ 50µg/mL against tumor lines: A549, HBL-100, HeLa, and T-47D. G. curtisii strains (GH-16-012 and GH-16-015) showed MIC values = 500µg/mL against Staphylococcus aureus. G. curtisii strain (GH-16-012) almost reduced by 50% the radical Galvinoxyl. Finally, G. curtisii strain (GH-16-023) presented the lowest level of toxicity with a LC50 of 490.881µg/mL against A. franciscana. These results support the potential medicinal effects of Mexican strains of G. curtisii.

Ganoderma sessile is a fast polysaccharide producer among Ganoderma species

ABSTRACT The selection of fast-growing and high-yield-producing strains is required to satisfy the market demand on fungal food supplements. To that aim, three strains deposited in our collection as G. lucidum and G. oregonense were screened for polysaccharide production and biomass yield. Ganoderma strains deposited as G. lucidum were identified as G. sessile and G. lingzhi by nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 (ITS) and translation elongation factor 1-α (TEF1-α) phylogenies. The identity of G. oregonense was confirmed by molecular phylogeny and biogeography. Additionally, mycelial antagonism confirmed species differentiation, and strains were further distinguished by morphology and protein profiles. Biomass and polysaccharide yields of G. sessile were clearly different from those of G. lingzhi and G. oregonense in both liquid culture and solid-state fermentation. The maximum polysaccharide yield (4.52 ± 0.83 g L−1) for G. sessile was obtained from submerged cultures at day 9. G. sessile also achieved the highest linear growth in lignocellulosic solid substrates. Consequently, basidiomata were successfully obtained by solid-state fermentation in polypropylene bags, whereas G. lingzhi and G. oregonense mushrooms were not produced in artificial solid substrates. G. sessile, a species frequently collected in America, showed to be a promising polysaccharide producer for the manufacture of dietary supplements.

Enhancement of ganoderic acid production by promoting sporulation in a liquid static culture of Ganoderma species

Ganoderic acids (GAs) produced by Ganoderma are a type of lanostane-type triterpenoids with anticancer and antimetastatic activities; however, low production of GAs limits its wide application. In this study, a novel strategy by promoting sporulation of Ganoderma was developed to increase GA production. First, a high-spore producing Ganoderma strain G. 260125 was obtained from dikaryotic strain CGMCC 5.0026, and the sporulation-specific gene of this strain exhibits a higher transcription level than CGMCC 5.0026. Then, the effect of promoting sporulation on GA content was investigated. The maximum ganoderic acid (GA)-T, GA-Mk, and GA-Me contents in G. 260125 in shake flasks were 358.97, 78.32, and 12.75 μg/100 mg dry weight, respectively, which were 3.42, 2.91, and 1.73 times higher than those obtained in CGMCC 5.0026. Moreover, total and individual GA contents in spores were significantly higher than those in liquid static culture. Both concentrations of intermediates and transcription levels of GA biosynthetic genes also improved in G. 260125 during fermentation compared with those in CGMCC 5.0026. For scaling-up experiments, GA-T, GA-Me, and GA-Mk production in G. 260125 improved by 2.2-, 2.6-, and 2.1-fold compared with those in CGMCC 5.0026. In addition, the effectiveness of the developed strategy was also confirmed in three different Ganoderma strains. This work illustrated that promoting sporulation efficiently improves GA production in liquid static cultures of Ganoderma.

Additions to the knowledge of Ganoderma in Thailand: Ganoderma casuarinicola, a new record; and Ganoderma thailandicum sp. nov.

Ganoderma is a cosmopolitan genus of mushrooms, which can cause root and butt rot diseases on many tree species. Members of this genus are particularly diverse in tropical regions. Some Ganoderma spp. are medicinally active and therefore are used to treat human diseases or as a dietary supplement. In this study, three Ganoderma strains were collected in tropical southern Thailand. Phylogenetic analyses of combined ITS, LSU, TEF1α and RPB2 sequence data indicated that the three strains grouped in a distinct lineage within laccate Ganoderma. One strain was collected from Surat Thani Province clustered in the G. casuarinicola clade with high statistical support (MLBS = 100% / MPBS = 98% / PP = 0.96), while the other two strains of Ganoderma, collected from Nakhon Si Thammarat Province, formed a distinct well-supported clade (MLBS = 100% / MPBS = 100% / PP = 1.00) and are described here as a new species. Ganoderma casuarinicola is reported here as a new record to Thailand. Morphological differences of the two taxa and their closely related taxa are discussed. Colour photographs of macro and micro morphological characteristics and a phylogenetic tree to show the placement of the new record and new species are provided.

Biodegradation of polycyclic aromatic hydrocarbons by native Ganoderma sp. strains: identification of metabolites and proposed degradation pathways.

Since polycyclic aromatic hydrocarbons (PAHs) are mutagenic, teratogenic, and carcinogenic, they are of considerable environmental concern. A biotechnological approach to remove such compounds from polluted ecosystems could be based on the use of white-rot fungi (WRF). The potential of well-adapted indigenous Ganoderma strains to degrade PAHs remains underexplored. Seven native Ganoderma sp. strains with capacity to produce high levels of laccase enzymes and to degrade synthetic dyes were investigated for their degradation potential of PAHs. The crude enzymatic extracts produced by Ganoderma strains differentially degraded the PAHs assayed (naphthalene 34-73%, phenanthrene 9-67%, fluorene 11-64%). Ganoderma sp. UH-M was the most promising strain for the degradation of PAHs without the addition of redox mediators. The PAH oxidation performed by the extracellular enzymes produced more polar and soluble metabolites such as benzoic acid, catechol, phthalic and protocatechuic acids, allowing us to propose degradation pathways of these PAHs. This is the first study in which breakdown intermediates and degradation pathways of PAHs by a native strain of Ganoderma genus were determined. The treatment of PAHs with the biomass of this fungal strain enhanced the degradation of the three PAHs. The laccase enzymes played an important role in the degradation of these compounds; however, the role of peroxidases cannot be excluded. Ganoderma sp. UH-M is a promising candidate for the bioremediation of ecosystems polluted with PAHs.

Diversity of Ligninolytic Enzymes and Their Genes in Strains of the Genus Ganoderma: Applicable for Biodegradation of Xenobiotic Compounds?

White-rot fungi (WRF) and their ligninolytic enzymes (laccases and peroxidases) are considered promising biotechnological tools to remove lignin related Persistent Organic Pollutants from industrial wastewaters and contaminated ecosystems. A high diversity of the genus Ganoderma has been reported in Cuba; in spite of this, the diversity of ligninolytic enzymes and their genes remained unexplored. In this study, 13 native WRF strains were isolated from decayed wood in urban ecosystems in Havana (Cuba). All strains were identified as Ganoderma sp. using a multiplex polymerase chain reaction (PCR)-method based on ITS sequences. All Ganoderma sp. strains produced laccase enzymes at higher levels than non-specific peroxidases. Native-PAGE of extracellular enzymatic extracts revealed a high diversity of laccase isozymes patterns between the strains, suggesting the presence of different amino acid sequences in the laccase enzymes produced by these Ganoderma strains. We determined the diversity of genes encoding laccases and peroxidases using a PCR and cloning approach with basidiomycete-specific primers. Between two and five laccase genes were detected in each strain. In contrast, only one gene encoding manganese peroxidase or versatile peroxidase was detected in each strain. The translated laccases and peroxidases amino acid sequences have not been described before. Extracellular crude enzymatic extracts produced by the Ganoderma UH strains, were able to degrade model chromophoric compounds such as anthraquinone and azo dyes. These findings hold promises for the development of a practical application for the treatment of textile industry wastewaters and also for bioremediation of polluted ecosystems by well-adapted native WRF strains.

Expression and characteristics of manganese peroxidase from Ganoderma lucidum in Pichia pastoris and its application in the degradation of four dyes and phenol

BackgroundManganese peroxidase (MnP) of white rot basidiomycetes, an extracellular heme enzyme, is part of a peroxidase superfamily that is capable of degrading the different phenolic compounds. Ganoderma, a white rot basidiomycete widely distributed worldwide, could secrete lignin-modifying enzymes (LME), including laccase (Lac), lignin peroxidases (LiP) and MnP.ResultsAfter the selection of a G. lucidum strain from five Ganoderma strains, the 1092 bp full-length cDNA of the MnP gene, designated as G. lucidum MnP (GluMnP1), was cloned from the selected strain. We subsequently constructed an eukaryotic expression vector, pAO815:: GlMnP, and transferred it into Pichia pastoris SMD116. Recombinant GluMnP1 (rGluMnP1) was with a yield of 126 mg/L and a molecular weight of approximately 37.72 kDa and a specific enzyme activity of 524.61 U/L. The rGluMnP1 could be capable of the decolorization of four types of dyes and the degradation of phenol. Phenol and its principal degradation products including hydroquinone, pyrocatechol, resorcinol, benzoquinone, were detected successfully in the experiments.ConclusionsThe rGluMnP1 could be effectively expressed in Pichia pastoris and with a higher oxidation activity. We infer that, in the initial stages of the reaction, the catechol-mediated cycle should be the principal route of enzymatic degradation of phenol and its oxidation products. This study highlights the potential industrial applications associated with the production of MnP by genetic engineering methods, and the application of industrial wastewater treatment.

DNA barcoding of wild Ganoderma specimens and cultivated strains in Hungary

The cosmopolitan polypore genus Ganoderma (Polyporales, Basidiomycota) has an enormous economic value, due to the caused diseases on different tree plantations (e.g. G. boninense in oil palms) and the medicinal properties of certain species (e.g. G. applanatum, G. lingzhi and G. sinense). The cultivated Ganoderma strains used by Hungarian growers originate both from selected wild strains or more often taxonomically not evaluated isolates with uncertain origin. However, based on morphological characteristics, the species concepts in the genus lack consensus, and the taxonomy of many Ganoderma taxa is thus problematic. Therefore, in addition to the morphological examination, suitable molecular methods have recently been required to the taxonomically correct identification of the wild Ganoderma species and cultivated strains in many cases. DNA barcode is a widely accepted tool for species identification and authentication of commercial products containing Ganoderma species. Among the tested fungal DNA barcoding markers, the application of the internal transcribed spacer (ITS) is the most commonly used and it was formally proposed as the primary fungal barcode marker. Besides the ITS, several other DNA barcoding markers were used by different authors to clarify taxonomic difficulties in Ganoderma: e.g. β-tubulin, LSU, rpb1, rpb2, Tef1-α or the mtSSU rDNA sequence. Formerly, the Hungarian Ganoderma species (viz. G. adspersum, G. applanatum, G. carnosum, G. cupreolaccatum, G. lucidum and G. resinaceum) were briefly studied by Papp and Szabo (2013, in Acta Silv. Lign. Hung. 9: 71–83.), however, based on solely morphological charactersitics. In this study we aimed (i) to generate DNA barcoding sequences for all wild Ganoderma species observed in Hungary; furthermore, (ii) to investigate and evaluate the Hungarian cultivated strains labelled as “G. lucidum” and the Ganoderma spp. isolates preserved in culture collections, based on DNA barcoding sequence analysis. Supported by the UNKP-17-4 New National Excellence Program of the Ministry of Human Capacities.

Genotyping of Ganoderma species by improved random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analysis

Species of Ganoderma are used in traditional medicines. An improved random amplified polymorphic DNA (RAPD) analysis, where the RAMP time is prolonged, has been used to characterize the genetic variation in some well known species of Ganoderma. The DNA materials were collected from ten Ganoderma strains, amplified with randomly selected 24 RAPD primers and evaluated by agarose gel electrophoresis. A cluster dendrogram was constructed for genetic analysis on the basis of amplification results. The improved RAPD amplified DNA with consistent and clear banding patterns. A total of 316 bands were found with 93% polymorphism. There was a significant genetic distance between the different strains of Ganoderma, with an index of similarity coefficient in the range of 0.52–0.74. The inter-simple sequence repeat (ISSR) analysis of the Ganoderma DNA samples showed similar trend results to the RAPD analysis with 0.49–0.81 similarity coefficients. This study reports the high level of genetic differences between different species or strains of a single species of Ganoderma and confirms the significance of the improved RAPD method in genetic characterization of organisms. Therefore, the improved RAPD combined with ISSR techniques might be used for the genetic characterization of organisms.

Screening of Ganoderma strains with high polysaccharides and ganoderic acid contents and optimization of the fermentation medium by statistical methods

Polysaccharides and ganoderic acids (GAs) are the major bioactive constituents of Ganoderma species. However, the commercialization of their production was limited by low yield in the submerged culture of Ganoderma despite improvement made in recent years. In this work, twelve Ganoderma strains were screened to efficiently produce polysaccharides and GAs, and Ganoderma lucidum 5.26 (GL 5.26) that had been never reported in fermentation process was found to be most efficient among the tested stains. Then, the fermentation medium was optimized for GL 5.26 by statistical method. Firstly, glucose and yeast extract were found to be the optimum carbon source and nitrogen source according to the single-factor tests. Ferric sulfate was found to have significant effect on GL 5.26 biomass production according to the results of Plackett-Burman design. The concentrations of glucose, yeast extract and ferric sulfate were further optimized by response surface methodology. The optimum medium composition was 55g/L of glucose, 14g/L of yeast extract, 0.3g/L of ferric acid, with other medium components unchanged. The optimized medium was testified in the 10-L bioreactor, and the production of biomass, IPS, total GAs and GA-T enhanced by 85, 27, 49 and 93%, respectively, compared to the initial medium. The fermentation process was scaled up to 300-L bioreactor; it showed good IPS (3.6g/L) and GAs (670mg/L) production. The biomass was 23.9g/L in 300-L bioreactor, which was the highest biomass production in pilot scale. According to this study, the strain GL 5.26 showed good fermentation property by optimizing the medium. It might be a candidate industrial strain by further process optimization and scale-up study.

In vitro growth of Ganoderma boninense isolates on novel palm extract medium and virulence on oil palm (Elaeis guineensis) seedlings

Aims: Basal stem rot (BSR) disease caused by Ganoderma pathogenic fungi, especially Ganoderma boninense is thriving rapidly in both areas with coastal and inland soils. The objectives of this study were to isolate and characterize Ganoderma isolates collected from various locations in Peninsular Malaysia through the comparison of their growth rate in vitroly on conventional and novel palm extract media, and to determine the degree of virulence caused by the isolates in oil palm seedlings. Methodology and results: In this study, 12 Ganoderma isolates were collected from infected oil palm trees, from various locations – Johor, Negeri Sembilan, Kedah, Perak, Pahang, and Kelantan, in Malaysia in year 2011. Twelve Ganoderma isolates were identified using molecular method with primer set that targeted at small-subunit 18S rDNA fragment, and characterized by determining the in vitro growth rate, and degree of virulence in 2-month-old oil palm seedlings in the nursery using both disease incidence (DI) and disease severity index (DSI) as the measurements to quantify the infection. All the Ganoderma isolates were identified as G. boninense and sequences of the respective isolates were deposited in GenBank. In general, all the isolates proliferated faster on oil palm extract medium (OPEM) compared to malt extract agar (MEA). Twelve G. boninense isolates were observed to illustrate different degree of virulence ranging from highly pathogenic to least pathogenic. Conclusion, significance and impact of study: Cultures of 12 G. boninense isolates were observed to show faster growth rate (P < 0.014) on OPEM under in vitro conditions compared to conventional MEA medium, except Bt Lintang G10 and GBA G12 isolates. OPEM medium could provide a better alternative for maintaining and culturing Ganoderma strains. In the current study, both DI and DSI were highly correlated. However, there were low linear relationships (R 2 < 0.423) between mycelia growth rate (on MEA and OPEM) and degree of virulence (DI and DSI) at 12-, 14- and 16weeks after treatments among the G. boninense isolates tested. Furthermore, different degrees of virulence in twelve separate Ganoderma isolates were reported. Therefore, it is crucial to incorporate more than one isolate into any researches on screening for Ganoderma resistance or tolerance planting materials, searching for potential biological control agents, and studying bitrophic or tri-trophic interactions. In addition, this study was aimed to isolate G. boninense strains with various virulence levels for future studies.

Biodegradation and detoxification of olive mill wastewater by selected strains of the mushroom genera Ganoderma and Pleurotus

Thirty-nine white-rot fungi belonging to nine species of Agaricomycotina (Basidiomycota) were initially screened for their ability to decrease olive-mill wastewater (OMW) phenolics. Four strains of Ganoderma australe, Ganoderma carnosum, Pleurotus eryngii and Pleurotus ostreatus, were selected and further examined for key-aspects of the OMW biodegradation process. Fungal growth in OMW-containing batch cultures resulted in significant decolorization (by 40–46% and 60–65% for Ganoderma and Pleurotus spp. respectively) and reduction of phenolics (by 64–67% and 74–81% for Ganoderma and Pleurotus spp. respectively). COD decrease was less pronounced (12–29%). Cress-seeds germination increased by 30–40% when OMW was treated by Pleurotus strains. Toxicity expressed as inhibition of Aliivibrio fischeri luminescence was reduced in fungal-treated OMW samples by approximately 5–15times compared to the control. As regards the pertinent enzyme activities, laccase and Mn-independent peroxidase were detected for Ganoderma spp. during the entire incubation period. In contrast, Pleurotus spp. did not exhibit any enzyme activities at early growth stages; instead, high laccase (five times greater than those of Ganoderma spp.) and Mn peroxidases activities were determined at the end of treatment. OMW decolorization by Ganoderma strains was strongly correlated to the reduction of phenolics, whereas P. eryngii laccase activity was correlated with the effluent’s decolorization.

AFLP analysis of genetic diversity in main cultivated strains of Ganoderma spp.

Ganoderma mushroom is one of the most prescribed traditional medicines, which has been used for medicinal purposes for centuries particularly in China, Japan, Korea and other Asian countries. In this article, the different strains of Ganoderma spp. used in production and their genetic relations of the closely related strains were identified and investigated at molecular level. The 30 Ganoderma strains were collected and analyzed using amplified fragment length polymorphism (AFLP) techniques. By using 8 primer combinations, the results showed that there were 52 polymorphic AFLP markers, and all accessions could be uniquely identified. Among the Ganoderma accessions, similarity coefficients ranged from 0.3282 to 0.746 in AFLP. The Ganoderma strains formed a tight cluster in eight groups in AFLP. Herein, among the collected Ganoderma spp., Ganoderma (from Korea) had some variations after introduction from original sites. These variances are related to different ecological habitats, and caused subtle discrimination in morphological traits and medical value. AFLP as a tool to identify the Ganoderma species or cultivars are very sensitive and practical.

An assessment of the genetic diversity within Ganoderma strains with AFLP and ITS PCR-RFLP

Ganoderma lucidum is one of the most important medicinal materials and plant pathogens. Because of its specific interhybridization, the genetic background, however, is relatively unclear. It made identification of Ganoderma strains, especially closely related strains difficulty. Amplified fragment length polymorphism (AFLP) using 14 primer combinations and internal transcribed spacer (ITS) PCR-RFLP were used in a comparative study which was designed to investigate the closely related Ganoderma strains genetic relations at molecular level. The analysis of 37 Ganoderma strains showed there were 177 polymorphic AFLP markers and 12 ITS PCR-RFLP markers, and all accessions could be uniquely identified. Among the Ganoderma accessions, similarity coefficients ranged from 0.07692 to 0.99194 in AFLP. The Ganoderma strains formed a tight cluster in nine groups in AFLP whereas seven groups in ITS PCR-RFLP. The cluster analysis revealed that the taxonomical system of subgenus Ganoderma is composed of Sect. Ganoderma and Sect. Phaeonema, and the strain 22 should be a variant form of strain 21. All methods delineated the Ganoderma strains from the different regions seeming to show a greater level of genetic diversity. It indicated that the genotype study at molecular level is a useful complement method to the current classification system of Ganoderma strains based on morphological traits. The congruency of the experiments was analyzed using the biostatistical software DPS V3.01.

Analysis of genetic diversity in Ganoderma population with a novel molecular marker SRAP

Genetic marker technology designed to detect naturally occurring polymorphisms at the DNA level had become an invaluable and revolutionizing tool for both applied and basic studies of fungi. To eliminate the confusion on the taxonomy of Ganoderma strains, in this study, a collection of 31 accessions representative of morphotypes and some unclassified types was used for analyzing molecular diversity using a novel molecular marker sequence-related amplified polymorphism (SRAP). This collection included commercial cultivars and wild varieties that represented the great diversification of types from different countries and regions. The experimental results showed that 50 out of 95 combinations of primers turned out to be polymorphic, and 85 polymorphism bands were obtained using six combinations. Based on the appearances of markers, the genetic similarity coefficients were calculated, and genetic variations were observed (0 approximately 1) among the 31 different Ganoderma strains. The group of Ganoderma lucidum showed significant differences from the group of Ganoderma sinense. Moreover, G. lucidum in China was also different from G. lucidum in Yugoslavia. At the same time, cluster analysis successfully categorized these 31 Ganoderma strains into five groups. These results revealed the genetic diversity of Ganoderma strains and their correlation with geographic environments. It also suggested SRAP marker could be used in the taxonomic analysis of fungi. To our knowledge, this is the first application of SRAP marker on the systematics of Ganoderma strains within basidiomycetes.

Molecular Systematics of Ganoderma: What Is Reishi?

Ganoderma is a very distinctive genus of white-rot polypore fungi that is primarily characterized by the formation of a double-walled, generally echinulate basidiospore. Most Ganoderma species are very variable macromorphologically and lack micromorphological distinctiveness. As a consequence, earlier taxonomic studies in the genus have created many synonymous names and have resulted in largely ambiguous species delimitation and identification systems, making species identification in the genus virtually impossible. Ganoderma strains used in oriental folk medicine refer to Reishi and have traditionally been labeled Ganoderma lucidum (W.Curt.: Fr.) P. Karst. in the scientific literature. However, there is now accumulative evidence that most species reported as G. lucidum in most of the pharmacological and phytopathological studies were wrongly identified.G. lucidum was first described as Boletus lucidus by William Curtis in 1781 from a filbert plant (= Corylus avellana) in London, UK. Curtis's original collection (i.e., the type specimen) has been lost. The actual type is represented in a color plate, which is in agreement with the International Code of Botanical Nomenclature. However, the typified plate is of no use for providing cultural characteristics and genetic information that would be useful for distinguishing G. lucidum from the other British laccate Ganoderma.Over the years, at least 166 laccate Ganoderma species have been described worldwide, of which at least 48 names were, at some point, considered to be synonyms of others. There is nevertheless a strong consensus about the true identity of G. lucidum among contemporary European mycologists. Molecular phylogenetic studies indicate that Ganoderma is a young genus in agreement with earlier morphological evidence as pointed out by the Norwegian mycologist Leif Ryvarden. DNA studies have shown that the G. lucidum species complex is composed of several species that can be difficult to distinguish from one another. These species include the European G. valesiacum Boud.; G. ahamdii Stey., described from Pakistan; North American G. tsugae Murrill and G. oregonense Murrill; and other taxa variously labeled G. resinaceum Boud., G. oerstedii Fr., and G. praelongum Murrill.Recent genetic and biogeographic studies have indicated that most Ganoderma species are geographically restricted. G. lucidum is probably restricted to western parts of Europe, although its distribution range can possibly also include parts of Siberia and of north western regions of China. Based on molecular phylogenetic evidence, it appears that most collections labeled G. lucidum in North America do in fact best correspond to the taxon labeled G. resinaceum in Europe, whereas G. tsugae in North America is genetically very close to the “true” G. lucidum from Europe.This leads to the question of what is the Oriental Reishi? A nonexhaustive molecular survey of taxa labeled G. lucidum in Asia, including strains commercially cultivated for the production of health tablets or teas, shows that this name has been largely misapplied and encompasses many distinct species.Incorrect taxonomic identification of Ganoderma strains hampers comprehensive strategies for drug discovery as well as for monitoring and managing diseases caused by Ganoderma in woody crops and forest ecosystems. Both molecular phylogenies and morphological evidence indicate that Africa probably harbors the highest genetic and taxonomic diversity in the genus.

Molecular Systematics of Ganoderma: What Is Reishi?

Volume 7, Issue 3, 2005 353 Ganoderma is a very distinctive genus of whiterot polypore fungi that is primarily characterized by the formation of a double-walled, generally echinulate basidiospore. Most Ganoderma species are very variable macromorphologically and lack micromorphological distinctiveness. As a consequence, earlier taxonomic studies in the genus have created many synonymous names and have resulted in largely ambiguous species delimitation and identifi cation systems, making species identifi cation in the genus virtually impossible. Ganoderma strains used in oriental folk medicine refer to Reishi and have traditionally been labeled Ganoderma lucidum (W.Curt.: Fr.) P. Karst. in the scientifi c literature. However, there is now accumulative evidence that most species reported as G. lucidum in most of the pharmacological and phytopathological studies were wrongly identifi ed. G. lucidum was fi rst described as Boletus lucidus by William Curtis in 1781 from a fi lbert plant (= Corylus avellana) in London, UK. Curtis’s original collection (i.e., the type specimen) has been lost. Th e actual type is represented in a color plate, which is in agreement with the International Code of Botanical Nomenclature. However, the typifi ed plate is of no use for providing cultural characteristics and genetic information that would be useful for distinguishing G. lucidum from the other British laccate Ganoderma. Over the years, at least 166 laccate Ganoderma species have been described worldwide, of which at least 48 names were, at some point, considered to be synonyms of others. Th ere is nevertheless a strong consensus about the true identity of G. lucidum among contemporary European mycologists. Molecular phylogenetic studies indicate that Ganoderma is a young genus in agreement with earlier morphological evidence as pointed out by the Norwegian mycologist Leif Ryvarden. DNA studies have shown that the G. lucidum species complex is composed of several species that can be diffi cult to distinguish from one another. Th ese species include the European G. valesiacum Boud.; G. ahamdii Stey., described from Pakistan; North American G. tsugae Murrill and G.oregonense Murrill; and other taxa variously labeled G. resinaceum Boud., G. oerstedii Fr., and G. praelongum Murrill. Recent genetic and biogeographic studies have indicated that most Ganoderma species are geographically restricted. G. lucidum is probably restricted to western parts of Europe, although its distribution range can possibly also include parts of Siberia and of north western regions of China. Based on molecular phylogenetic evidence, it appears that most collections labeled G. lucidum in North America do in fact best correspond to the taxon labeled G. resinaceum in Europe, whereas G. tsugae in North America is genetically very close to the “true” G. lucidum from Europe. Th is leads to the question of what is the Oriental Reishi? A nonexhaustive molecular survey of taxa labeled G. lucidum in Asia, including strains comMolecular Systematics of Ganoderma: What Is Reishi?