Twelve strains of bacteria with cellulase and xylanase activities were isolated from spent mushroom substrates collected from button mushroom cultivation farm, Buye, Chungcheongnam-do in Korea. Among them, one strain, designated NO12, with higher cellulase and xylanase activities was selected by agar diffusion method. The strain NO12 was identified to be a Bacillus sp. by biochemical characteristics using Bacillus ID kit and MicroLog system. Comparative 16S rDNA gene sequence analysis showed that strain NO12 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus subtilis with 16S rDNA gene sequence similarity of 99.2%. Based on its physiological properties, biochemical characteristics, and phylogenetic distinctiveness, strain NO12 was classified within the genus Bacillus, for which the name Bacillus subtilis NO12 was proposed. The cellulase and xylanase activities of B. subtilis NO12 were slightly increased according to bacterial population from exponential phase to stationary phase in the growth curve for B. subtilis NO12. The xylanase activity continuously increased from the beginning of the exponential phase and exhibited maximum activity in the middle of the exponential phase.

In this study, we investigate the potential use of persimmon peels (PP) in mushroom culture medium for the production of functional mushrooms. Pleurotus eryngii was cultivated in medium supplemented with PP (SMPP) at the following concentrations: 0% SMPP (control), 5% SMPP, 10% SMPP, 15% SMPP, 20% SMPP, or 30% SMPP. The total polyphenol content, DPPH radical scavenging ability, ABTS cation scavenging ability, and reducing power of P. eryngii cultivated in SMPP were investigated. P. eryngii cultured in 20% SMPP produced the highest values for all four measurements. Total polyphenol content, DPPH radical scavenging activity, ABTS cation scavenging ability, and reducing power all increased upon the addition of PP. Based on our results, we can conclude that persimmon peels are a highly valuable supplement for functional mushroom culture medium.

We measured the antioxidant activities of Oak mushroom (Lentinula edodes) in browned sawdust medium under conditions of varying LED sources and amounts of light. Consequently, exposure to 200Lx blue LED resulted in highly efficient browning; the most efficient browning was shown at 200Lx, regardless of the type of luminous source. We identified that quantities obtained with the blue luminous source increased compared to those in other treatment plots. The DPPH radical scavenging test conducted to examine antioxidant activity revealed that the red luminous source caused high radical scavenging compared to efficient browning. The fruiting body for Nongjin-go, as a treatment plot with the highest scavenging, under a 400Lx red luminous source was 34.3±1.80% and that for ‘Sanjo 701’ at a 300lx red luminous source was 32.99±1.58%. The polyphenol content, reported to be correlated with DPPH radial scavenging, showed no similar correlation in the ‘Nongjin-go’ variety. By contrast, ‘Sanjo 701’ showed a similar association.

Volvariella volvacea is mainly cultivated in subtropics area like South-East Asia. Because it is cultivated in rice straws, it is called a straw mushroom. That mushroom grows well in high temperature about 30~38°C and high humidity. Straw mushroom is a homothallic mushroom, so it is difficult to identify whether the offspring is different from the parents. This study was carried out to investigate RAPD primers that can be used for identification the DNA polymorphism of Volvariella volvacea genetic resources. 9 strains were collected from various countries like China, Vietnam etc. When ITS regions of their DNA were analyzed, they proved to be Volvariella volvacea. A cultivation test was conducted to measure the morphological characteristics of them 2 strains, KMCC04380 and KMCC04382 were selected for breeding resources because the mycelium of them grew well on medium and fruiting bodies were formed quickly. The Universal PCR Fingerprinting kits(UPF primers) were used to confirm the genetic polymorphisms of the 2 strains. As a result of confirming the DNA bands, 2 of 12 primers could be used to genetically distinguish 2 strains. About 50 spores were isolated from their fruiting bodies respectively and they also will be confirmed DNA polymorphisms by using UPF primers.

H. mamoreus is a mushroom with abundant favor and medicinal use. However, its cultivation has problems such as the long cultivation period, low biological efficiency and microbiological contamination, so new cultivars should be developed. In this study, 55 strains of H.marmoreus were analyzed with ISSR markers to identify precise genetic information in collected germplasm as mother strains in breeding. ISSR 13 and 15 markers were confirmed polymorphism. The three strains (KMC03106, KMC03107, and KMC03108) with white cap color were close genetic relationship in the UPGMA analysis of both the ISSR 13 and 15 markers. Especially in the PCR result of the ISSR 15, the collected germplasm were differentiated to three groups following collecting year. As these results, the ISSR 15 marker would be able to classify the phylogeny of cap color and genetic variation along the collecting year. Therefore ISSR markers will confer effective selection of mother strains for breeding of H. mamoreus.

Tremella fuciformis has about 40 species worldwide, and is widely distributed in the subtropical, tropical, and temperate regions. Tremella fuciformis is known to have been eaten by poppy in Chinese classics and has been a symbol of beauty since ancient times. In fact, it has been known that the extract of the Tremella fuciformis induces inhibition of melanin formation of the cells to have a skin whitening effect and to prevent wrinkles caused by UV stimulation damage, thereby improving wrinkles. Tremella fuciformis was first cultivated in Sichuan province, China, and is now cultivated in China and Southeast Asia. China has succeeded in large-scale artificial cultivation of Tremella fuciformis, but there is no research on mass artificial cultivation in Korea. Therefore, this study was carried out to develop standard cultivation technique for mass production of Tremella fuciformis. In order to select the optimal medium for Tremella fuciformis, five kinds of medium such as PDA, MCM, MEA, YM and CDA were used. Tremella fuciformis showed the best growth on PDA medium, and Annulohypoxylon stygium showed the best growth on MCM. The growth of Tremella fuciformis was good at pH 5 , and Annulohypoxylon stygium showed the best growth at pH 6. The optimum temperature for Tremella fuciformis and Annulohypoxylon stygium was 25 °C. Carbon source and nitrogen source were selected to establish optimal culture conditions.

Lentinula edodes are mainly used for cultivation and food in Korea. Consumption is gradually increasing with the characteristic smell and taste. In addition, anti-cancer effect, hypertension, atherosclerosis and other effects have been proven to be a functional food. The cultivation method of highland rice changed from lumber to sawdust bag. Thus, a browned step is required so that the surface of the medium can act like a tree epidermis. The browned medium is not easily contaminated with other bacteria even when in contact with the outside air. It is also a necessary step because it suppresses evaporation of water in the medium and helps mushroom production. But it takes a very long time to browning. Therefore, it is necessary to study the browning of the medium during the cultivation of the altitude. Therefore, the color of the Lab color was measured using a colorimeter to determine the browning efficiency of the medium by LED light source type and intensity. The varieties were Nongjingo and Sanjo-701. The LED light sources were divided into upper, middle, and lower by setting the blue, green, white, and red colors at 100 to 500 ㏓. L values of light source showed the greatest decrease in blue color, followed by white, green and red. It was confirmed that the L value of Sanjo 701 was lower than that of Nongjingo. The decrease of L value by the type of light source showed the same tendency as Nongjingo, and blue was the most decreased, followed by white, green and red.

Cladobotryum mycophilum is the causal agent of cobweb disease of commercial mushrooms. Symptoms were noticed as round, fleshy, yellowish brown lesions on mushroom caps and progressed when the parasitic fungus formed white cobweb circular colonies on dead or damaged pinheads, spread on the surface of the casing. Two gram-positive bacterium were isolated from mushroom media that markedly showed the antagonistic activity against C. mycophilum.. These isolates were identified as Bacillus altitudinis and Bacillus subtilis by analysis of the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacteria is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacteria cell was sufficient for inhibition in vitro for C. mycophilum. Control efficacy of browning disease of Bacillus altitudinis treatment was 78% on Agaricus bisporus. The optimal culture medium was determined as follows: 3% Soluble startch, 10% Soytone, 1% (NH4)2HPO4, 1 mmol KCl, and 0.5% L-asparagin at pH 6.0 at 30°C. Control efficacy of browning disease of Bacillus subtilis treatment was 71% on Agaricus bisporus. The optimal culture medium was determined as follows: 1.5% Xylose, 2% Soytone, 1% NH4H2PO4, 7 mmol CaCl2, and 0.5% Histidine at pH 6.0 at 25°C. Accordingly, the suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by C. mycophilum.

Although Agaricus bisporus mushroom is a popular mushroom consumed world-widely, the application of common bio-elements to verify its geographical origin remains highly limited. Therefore, this study aimed to verify whether the six cultivation regions in Korea of A. bisporus could be determined by the stable isotope composition analysis of bio-elements, which are unique and abundant in most living creatures. δ13C, δ15N, δ18O, and δ34S in A. bisporus were influenced by the region, cultivar, and the interactions between these two factors (P < 0.05). In particular, the effect of cultivation region was more significant to the isotope ratio profiles as compared to the mushroom cultivar effect. During the cultivation period of A. bisporus, the C, N, O, and S isotopic fractionation was observed between the mushroom and cultivation medium, note higher in the mushroom (P < 0.05). Two dimensional plot of δ15N, δ18O, or δ34S effectively distinguished the cultivation regions, Nonsan, Buyeo, Boryung, Daegu, and/or Gyeongju examined in this study. Further, these isotope ratio profiles measured in this study would be statistically analyzed with various chemometrics to provide isotope markers for the authenticity of geographical origin. Our preliminary case study improves our understanding of how the isotope composition of A. bisporus varies with respect to cultivation regions and cultivars. In conclusion, the analysis of stable isotope ratios is a suitable potential tool for discrimination between the cultivation origins of A. bisporus collected from Korea, with potential application to other countries after certain validation steps required.

The total mushroom production in Korea in 2015 comprised about 200,000 ton with a value of about 700 billion won (one trillion won if mushroom factory products are included, 1 $=1,128 won). This is almost equal to the amounts generated by flowers and medicinal crops. Even though the cultivation area and the number of farms have been decreased since 2006, the scale of the farms is increasing. Also mushroom productivity and consumption (4.9 ㎏ / person in 2015) are steadily increasing. Major cultivated species are Flammulina velutipes, Pleurotus ostreatus, Pleurotus eryngii, Lentinula edodes and Agaricus bisporus, which cover 90% of the total production. Shelves, logs, plastic bags or plastic bottles are mostly used for cultivation depending on the kind of mushroom. Mushroom export estimated about 43 million $ in 2016. Major exported mushrooms are Flammulina velutipes, Pleurotus eryngii, Lentinula edodes, Pleurotus ostreatus, Tricholoma matsutake and Agaricus bisporus that are destined for the U.S., the Netherlands, Australia, Canada, Hong Kong, Japan and several other countries. Mushroom research in the RDA started in 1967. In the beginning, development of cultivation methods using rice straw was studied together with distribution of improved strains of the button mushroom. The costs of button mushroom production strongly increased due the improving national economy, shortage of workers, increase of wages and the oil crisis in the nation. This caused a weak competitive position for button mushroom export and resulted in reduction of the button mushroom cultivation area. After development of a cotton waste cultivation method for the oyster mushroom (Pleurotus ostreastus), this mushroom was popularized and mainly studied. Development of automated plastic bottle cultivation systems in the 1990s changed shelf cultivation to mass production. The bottle system was applied to the oyster mushroom but also to F. velutipes and P. eryngii. Mushroom research in the RDA nowadays focuses on analysis of mushroom genetics in combination with development of new mushroom varieties, mushroom physiology and cultivation. Further studied are environmental factors for cultivation, disease control, development and utilization of mushroom substrate resources, post-harvest management and improvement of marketable traits. Finally, the RDA manages the collection, classification, identification and preservation of mushroom resources.

The choice of strain, substrate, and environmental conditions are fundamental factors that determine the ability of a fungus to develop and produce mushrooms with high quality. The objective of this study was to compare the strains of Lentinula edodes and Ganoderma lucidum originated from South Korea and Brazil in relation to their vegetative development in different culture media, to obtain isolates with high quality. The strains of the two mushroom species from Brazil and South Korea grew slowly, possibly because of abiotic factors or storage technique used. However, it may be concluded that temperature, humidity, light, pH, and nutrients from the substrate, if not regulated appropriately may affect the vegetative species.

Microsatellite SSR markers were developed and utilized to reveal the genetic diversity of 32 strains of Flammulina velutipes collected in Korea, China, and Japan. From the SSR-enriched library, 490 white colonies were randomly selected and sequenced. Among the 490 sequenced clones, 85 (17.35%) were redundant. Among the remaining 405 unique clones, 201 (49.6%) contained microsatellite sequences. We used 12 primer pairs that produced reproducible polymorphic bands for four diverse strains, and these selected markers were further characterized in 32 Flammulina velutipes strains. A total of 34 alleles were detected using the 12 markers, with an average of 3.42 alleles, and the number of alleles ranged from two to seven per locus. The major allele frequency ranged from 0.42 (GB-FV-127) to 0.98 (GB-FV-166), and values for observed (HO) and expected (HE) heterozygosity ranged from 0.00 to 0.94 (mean = 0.18) and from 0.03 to 0.67 (mean = 0.32), respectively. SSR loci amplified with GB-FV-127 markers gave the highest polymorphism information content (PIC) of 0.61 and mean allele number of five, whereas for loci amplified with GB-FV-166 markers these values were the lowest, namely 0.03 and two. The mean PIC value (0.29) observed in the present study with average number of alleles (3.42). The genetic relationships among the 32 Flammulina velutipes strains on the basis of SSR data were investigated by UPGMA cluster analysis. In conclusion, we succeeded in developing 12 polymorphic SSRs markers from an SSR-enriched library of Flammulina velutipes. These SSRs are presently being used for phylogenetic analysis and evaluation of genetic variations. In future, these SSR markers will be used in clarifying taxonomic relationships among the Flammulina velutipes.

In Korea, oyster mushroom is one of the commonly cultivated mushrooms. In 2013, the cultivation areas and products of oyster mushrooms were 60,039 M/T and 201 ha, respectively. Many species of oyster mushrooms are cultivated in various countries. These include Pleurotus ostreatus, P. florida, P. sajor-caju, P. eryngii, P. citrinopileatus, P. salmoneostramineus and P. cystidiosus. P. citrinopileatus is a yellow oyster mushroom famous for its health benefits such as anti-cancer and anti-oxidant effects. Therefore, a cultivar P. citrinopileatus ‘Jangdari’ was developed to improve yield and the ability to grow well at lower temperatures. Two parent strains ‘Gumbit (KMCC02150)’ and ‘KMCC02145’ were selected based on their morphological characteristics. ‘Jangdari’ was developed by the method of Mon-Mon crossing between monokaryons derived from ‘Gumbit’ and ‘KMCC02145’, and finally selected through continuous cultivation tests. The optimum temperature for mycelial growth was 30oC. The cultivar could grow well at high temperatures, especially 16~24oC. Fruiting body production per bottle (850 mL) was about 90.0 g. Stipe length and thickness of ‘Jangdari’ were similar to those of ‘Gumbit’. ‘Jangdari’ was more resistant to low temperature than ‘Gumbit’, and thus it could be cultivated with oyster mushrooms (P. ostreatus). In addition, while cultivating ‘Jangdari’, it is not required to scrape out the upper side of bottle’s sawdust medium; hence, its cultivation is expected to save energy and time.

Microsatellite SSR markers were developed and utilized to reveal the genetic diversity of 32 strains of Flammulina velutipes collected in Korea, China, and Japan. From SSR-enriched library, 490 white colonies were randomly selected and sequenced. In the 490 sequenced clones, 85 clones (17.35%) were redundant. Among the remaining 405 unique clones, 201 clones (49.6%) contained microsatellite sequences. As a result, 12 primer pairs produced reproducible polymorphic bands within diverse 4 strains and these selected markers were further characterized in 32 Flammulina velutipes strains. A total of 34 alleles were detected using the 12 markers, with an average of 3.42 alleles and the number of alleles ranged from two to seven per locus. The major allele frequency ranged from 0.42 (GB-FV-127) to 0.98 (GB-FV-166), and values for observed (HO) and expected (HE) heterozygosity ranged from 0.00 to 0.94 (mean = 0.18) and from 0.03 to 0.67 (mean = 0.32), respectively. SSR loci amplified with GB-FV-127 markers gave the highest polymorphism information content (PIC) of 0.61 and mean allele number of five, while for loci amplified with GB-FV-166 markers these values were the lowest, namely 0.03 and two. The mean PIC value (0.29) observed in the present study with average number of alleles (3.42). The genetic relationships among 32 Flammulina velutipes strains based on SSR data were generated by UPGMA cluster analysis. In conclusion, we succeeded in developing 12 polymorphic SSRs markers from SSR-enriched library of Flammulina velutipes. These SSRs are presently being used for phylogenic analysis and evaluation of genetic variations. In future, these SSR markers will be used in clarifying taxonomic relationships among the Flammulina velutipes.

The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 11,493 M/T in 2014. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Trichoderma harzianum is the causal agent of green mould disease of commercial mushrooms. Early symptoms were noticed as round, fleshy, brown lesions on mushroom caps. Late symptoms spread on the surface of the casing, and covered entirely fruiting bodies. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Trichoderma harzianum, the destructive pathogen of cultivated mushrooms. The CH518 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus methylotrophicus by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Trichoderma harzianum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Trichoderma harzianum. Control efficacy of browning disease of strain CH518 treatment was 77.7% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 3.0% saccharose, 1.5% Soytone, 1% NH4H2PO4, 10 mM MgSO4, and 2.0% glutamic acid at pH 6.0 at 25°C. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Trichoderma harzianum.

‘Baekseung’, a new variety of Flammulina velutipes, was bred by mating two monokaryotic strains isolated from KMCC 4210 and KMCC 4216 in the Mushroom Research Division, Baekseung ARES in 2016. The Baekseung and Uri1ho strains showed fast mycelial growth and mycelial density on malt extract agar media after 7 days of incubation. The spawn running period on the sawdust substrate required a cultivation period and temperature of 30 days and 25oC, respectively, for primordia formation where in fruiting body development occurred from 11±1 days at 14oC and 14±1 days at 7oC. The length of the pilei and stipes of the Baekseung harvested in optimal stag were 11.3±0.4 and 89.2±7.1 mm, respectively, whereas the values for Uri1ho were 10.7±1.0 and 91.3±20.8 mm, respectively. The yield of the Baekseung and Uri1ho strain grown on the sawdust substrate was 153.7±12.5 and 139.8±17.8 g, respectively, per 850 ml in bottle cultivation. The inferred tree exhibited a phylogenetic relationship between the Korean white fruiting body strains of Baekseung, Uri1ho and Fv-14-a-38, Fv-14-a-51, and the Japanese white fruiting body-forming strains of KMCC 4226, and these were confirmed to be genetically related.

Supplemental substrates for mushroom cultivation media are potent sources for fungal contamination of indoor environment in cultivation houses. The present study was performed to investigate the presence of harmful fungi in the supplemental materials (beet pulp, cotton seed meal, kapok meal, peat moss, wheat straw) imported from China, Egypt, Germany, Indonesia and Pakistan. Fungal concentration in the supplemental materials ranged from 1.3×102 to 1.8×103 cfu/g. A total of 11 genera and 21 species were identified. Two genera and two species were found in Germany peat moss. In Pakistan wheat straw, three genera and four species were detected. In Egypt beet pulp and China cotton seed meal, four genera and five species and seven genera and ten species were shown, respectively. Among the identified fungi, Acremonium sp., Aspergillus chevalieri, Cryptococcus adeliensis, Eurotium amstelodami, Paecilomyces variotii and Rhodotorula mucilaginosa were known as human pathogens. This study provided evidence that pathogenic yeast and filamentous fungi are present in imported agricultural byproduct materials for mushroom cultivation.

Oyster mushrooms are widely cultivated and consumed in Korea. P. ostreatus 'Suhan(ASI 2504)' is an ideal cultivar for mushroom farmers due to its dark pileus and thick stipe; however, as it is very sensitive to environmental conditions, an alternative cultivar is required. To develop a new cultivar, parental strains 'Suhan(ASI 2504)' and ‘ASI 0665 (Heuktari)’ were selected from various collected strains according to morphological characteristics. P. ostreatus ‘Soltari’ was developed by Di- Mon crossing between the dikaryotic strain ‘Suhan’ and the monokaryotic strain derived from ‘Heuktari’. Thirty-eight of the 100 crossed strains were selected following analysis of mitochondrial genetic characteristics, and 'Soltari' was ultimately selected by continuous cultivation tests. The mitochondrial DNA profile of ‘Soltari’ was found to be the same as that of ‘Heuktari, and a nuclear DNA profile of ‘Soltari’ was similar as those of the parental strains, ‘Suhan’ and ‘Heuktari.’ 'Soltari' mycelium grows adequately in moderate to high temperatures of 12–20oC, although its optimum temperature was found to be 30oC. Fruiting body production per 1.1-L cultivation bottle was approximately 158.8 g. Its stipe length and thickness were comparable to those of diameter and thickness were somewhat lower (42.72 vs. 51.33 mm and 18.18 vs. 22.46 mm, respectively). ‘Soltari’ was found to be more resistant to high CO2 atmosphere than 'Suhan', and the color of the pileus of 'Soltari' was dark gray at high temperature. Therefore, it is suggested that this new cultivar ‘Soltari’ is a good alternative cultivar and will contribute to energy saving in oyster mushroom farms.

The production scale of mushrooms in Korea is approximately 600 billion won, which is 1.6% of Korea’s gross agricultural output. In Korea, ca. 190,000 tons of mushrooms are harvested annually. Although the numbers of mushroom farms and cultivators are constantly decreasing, total mushroom yields are increasing owing to large-scale cultivation facilities and automation. The recent expansion of the well-being trend has caused an increase in mushroom consumption in Korea: the annual per capita mushroom was 3.9 kg (’13), whichis a little higher than that in Europe. Thus, mushroom export, mainly Flammulina velutipes and Pleurotus ostreatus, has increased since the mid-2000s. Recently, however, it is slightly reduced. Nevertheless, Vietnam, Hong Kong, the United States, and the Netherlands continue to export mushrooms, and Korea has increased its export to Australia, Canada, Southeast Asia, etc. Canned Agaricus bisporus, the first export of the Korean mushroom industry, reached it speak sales in 1977-1978. When Korea initiated trade with China in 1980, the international prices of mushrooms fell sharply, leading to shrinkage of the domestic markets. Spurred by the high demand to develop substitute goods for A. bisporus, the oyster mushroom (P. ostreatus) gained attention since it seemed to suit the taste of Korean consumers. Although the log cultivation technique for oyster mushroom was developed in the early 1970s, it required a great deal of labor. Thus, we developed the shelf cultivation technique, which is easier to manage and allows for mass production. In this technique, the growing shelf is made mafrom fermented rice straw, whichis the only P. ostreatus medium in the world and isused only in South Korea. After then, the use of cotton wastes as an additional material of medium, the productivity. Currently, we are developing a standard cultivation technique and environmental control system that can stably produce mushrooms throughout the year. The increase of oyster mushroom production may boostthe domestic market and contribute to industrial development. In addition, oyster mushroom production technology played a role in forming the basis for the development of bottle cultivation, which made mass production . In particular, bottle cultivation using liquid spawn could allow for the export of F. velutipes and Pleurotus eryngii. In addition, the white varieties of F. velutipes were second developed in the world after Japan. We also developed the new A. bisporus cultivar ‘Saeah’, which is easy to grow in Korea. In hopes to advance the mushroom industry, we will continue to develop cultivars with international competitive power and to improve cultivation techniques.

Pleurotus cornucopiae (PC) mushrooms is found in the field and commonly known in Japan as Tamogidake mushrooms. Recently it has been reported that PC also alleviating the toxicity of heavy metals. However little is known about mechanism of the action of PC on osteoblast differentiation, especially in transcription factor. Inhibitor of DNA binding-1 (Id-1) function has been linked to the proliferation, migration, and senescence of cells, and studies about relationship between Id-1 and biological function. Therefore, this study was aimed to investigate the effect of PC on osteoblast differentiation and expression of Id-1 and Id-2. PC treatment increased ALP, Col 1 and OCN. PC treatment up-regulated the mRNA levels of Id-1 and Id-2 genes. This PC–induced osteoblast differentiation is more effective in lower doses rather than high doses. This study shows that expression of Id-1 and Id-2 was increased in a dose-dependent manner during PC-induced osteoblast differentiation.