• Journal of Food Hygiene and Safety
• /
• v.38 no.5
• /
• pp.287-296
• /
• 2023

Mushroom consumption is gradually growing annually worldwide for many centuries. Oyster mushrooms (Pleurotus ostreatus), button mushrooms (Agaricus bisporus), and enokitake (Flammulina filiformis) are mainly consumed in Korea. However, mushrooms can be contaminated with pathogenic microorganisms, such as Listeria monocytogenes, because antibacterial treatment during mushroom cultivation and processing is insufficient. Therefore, many cases of mushroom contamination-related foodborne illnesses and food recalls have been reported. Three representative treatments are used to prevent microbial contamination in mushrooms: chemical, physical, and combination treatments. Among the chemical treatments, chlorine compounds, peroxyacetic acid, and quaternary ammonium compounds are commercially used and ozone and electrolyzed water has recently been used. Additionally, physical treatments, including ultrasound, irradiation, and cold plasma, are being developed. Combination techniques include ultraviolet/chlorine compounds, ozone/organic acid, and ultrasound/organic acid. This review describes the domestically consumed mushroom types and their characteristics, and investigates the mushroom contamination levels. Additionally, effective antibacterial technologies for reducing microbial contamination in mushrooms are also discussed.

• Journal of Mushroom
• /
• v.8 no.3
• /
• pp.122-130
• /
• 2010

Common mushroom production per area has been decreased and are up to less than 50% of the 1980 production. To determine the main reasons for the decrement, we performed this study. Two main reasons, which are mushroom disease and the low compost quality because of mechanized compost making, were assessed. In mechanized mushroom farms, nitrogen concentration in compost was lower than recommended and total compost quantity was about 100-150 $kg/3.3m^2$, which was also lower than usual. Our study revealed that higher nitrogen concentration (about 1.5%) in compost gave better production. Also, use of large amount of compost appeared to increase the mushroom production, although more insects and disease problems were observed. The relationships between the presences of microorganisms and occurrence of diseases were assessed by monitoring the microorganism densities near the mushroom farms. Higher number of microorganisms were observed near the mushroom farm area, compared to control region, Daechon beach. Most contaminating molds were found in the circulating fans, tunnel and culture room floor. The bacterial isolates were collected from the air in mushroom culture room and killed with 0.005% Benzalkonium solution, indicating treatment of Benzalkonium are the effective methods to sanitize the mushroom culture room.

• Journal of Mushroom
• /
• v.14 no.4
• /
• pp.142-154
• /
• 2016

Worldwide production of mushrooms has been increasing by 10-20% every year. Recently, Pleurotus eryngii and P. nebrodensis have become popular mushroom species for cultivation. In particular, China exceeded 8.7 million tons in 2002, which accounted for 71.5% of total world output. A similar trend was also observed in Korea. Two kinds of mushrooms-Gumji (金芝; Ganoderma) and Seoji-are described in the ancient book 'Samguksagi' (History of the three kingdoms; B.C 57~A.D 668; written by Bu Sik Kim in 1145) during the Korea-dynasty. Many kinds of mushrooms are also described in more than 17 ancient books during the Chosun-dynasty (1392~1910) in Korea. Approximately 200 commercial strains of 38 species of mushrooms were developed and distributed to cultivators. The somatic hybrid variety of oyster mushroom, 'Wonhyeong-neutari,' was developed by protoplast fusion, and distributed to growers in 1989. Further, the production of mushrooms as food was 199,829 metric tons, valued at 850 billion Korean Won (one trillion won if mushroom factory products are included) in 2015. In Korea, the major cultivated species are P. ostreatus, P. eryngii, Flammulina velutipes, Lentinula edodes, Agaricus bisporus, and Ganoderma lucidum, which account for 90% of the total production. Since mushroom export was initiated in 1960, the export and import of mushrooms have increased in Korea. Technology was developed for liquid spawn production, and automatic cultivation systems led to the reduction of production cost, resulting in the increase in mushroom export. However, some species were imported owing to high production costs for effective cultivation methods. In academia, RDA scientists have conducted mushroom genome projects since 1997. One of the main outcomes is the whole genome sequencing of Flammulina velutipes for molecular breeding. With regard to medicinal mushrooms, we have been conducting genome research on Cordyceps and its related species for developing functional foods. There are various kinds of beneficial substances in mushrooms; mushroom products, including pharmaceuticals, tonics, healthy beverages, functional biotransformants, and processed foods have also became available on the market. In addition, compost and feed can likewise be made from mushroom substrates after harvest.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.8
• /
• pp.1087-1096
• /
• 2010

This study was conducted to investigate the physiological activity of extracts of fresh mushrooms. The components were extracted by hot water; subsequently, the hot-water extract was subjected to 60% ethanol precipitation to yield high-molecular-weight (HMW) and low-molecular-weight (LMW) fractions. Total polyphenol contents, $\beta$-glucan contents, electron-donating ability (EDA), superoxide dismutase (SOD)-like activity, nitrite-scavenging activity, fibrinolytic activity, nitric oxide (NO) production, and inhibition of NO production of the mushroom extracts were measured using lipopolysaccharide (LPS)-stimulated murine macrophages, RAW 264.7 cells. The extracts of Lentinus edodes (Berk.) Singer and Pleurotus ostreatus (Fr.) Kummer contained the highest levels of $\beta$-glucan (33.5% and 25.57%, respectively). Further, the LMW fractions of the Phellinus linteus contained the highest levels of polyphenols (233.23 mg/g). The EDA of LMW fractions (10 mg/mL) of the Phellinus linteus and Agaricus bisporus were 80.74% and 51.35%, respectively. Further, SOD-like activities of the LMW fractions were high as compared to those of the HMW fractions. Nitrite-scavenging activities of the LMW fractions (pH 1.2; concentration, 10 mg/mL) of the Phellinus linteus and Pleurotus ostreatus (Fr.) Kummer were 75.95% and 41.05%, respectively. The fibrinolytic activity of the LMW fractions of all mushrooms showed no enzyme activity by fibrin plate assay. The fibrinolytic activity of the extracts of Tricholoma matsutake was the greatest inhibitory activity at 60.4%. Further study revealed that the mushroom extracts exhibited anti-inflammatory effects on RAW 264.7 cells. The LMW fraction ($500\;{\mu}g/mL$) of the Phellinus linteus considerably inhibited NO production (100%).

• Applied Biological Chemistry
• /
• v.18 no.4
• /
• pp.203-218
• /
• 1975

In order to investigate the compositional change oil composts during the growing of cultivated mushroom (Agaricus bisporus), composts and mushrooms during the period of filling to ending under commercial conditions were subjected to chemical analyses. The results are summarized as follows and the mechanism of composting for mushroom cultivation was proposed. 1) The temperature change of growing bed and room was observed and the yield of mushroom for each cropping time was recorded to get $15.6kg/m^2$ in total crops. 2) Composts after filling showed pH 8.2 which dropped to 6.4 after casing and continued so up to ending. 3) On the dry weight basis of composts, crude ash increased whereas total nitrogen, ether extract and crude fibre decreased gradually to bring about the lowering of organic matter. 4) Total nitrogen of composts decreased gradually and more insoluble nitrogen was lost than soluble nitrogen. The C/N ratio of composts was initially 21 which was gradually lowered to 16. 5) The losses of ${\alpha}-cellulose$, pentosan and lignin in composts were 87%, 75%, and 60%, respectively, in which ${\alpha}-cellulose$ decreased markedly after casing. 6) Free reducing sugars of composts increased continuously. Gradually increased free amino acids till second cropping decreased again thereafter. Composts at the filling stage contained alanine, glutamic acid, glycine and serine in which glycine decreased markedly whereas proline increased remarkably upon mushroom cultivation. 7) Among minerals of composts, phosphorus and zinc tended to decrease, potassium and copper tended to increase anti sodium showed no marked change. 8) In comparison of mushrooms from different cropping time with respect to proximate composition, minerals, free reducing sugars and amino acids, no marked difference was observed. However, a little higher values were observed in crude fat, free reducing sugars and sodium content for early crops and in free amino acids and phosphorus content for late crops. Twelve free amino acids including alanine, serine, threonine, and glutamic acid were detected in the cultivated mushroom. 9) According to above experimental results, it was possible to support the mechanism of compositing that the formation of ammonia and decomposition of carbohydrates by mesophiles are followed by protein biosynthesis, formation of microbial bodies and nitrogen-rich lignin humus complex by thermophiles, thus supplying necessary nutrients for mushroom growth, along with residual carbohydrates.

• The Korean Journal of Mycology
• /
• v.1 no.1
• /
• pp.3-11
• /
• 1973

Four species of nematodes attacking mushroom beds were found in samples taken from 35 mushroom farms throughout Korea. These were Rhabditis sp., Aphelenchoides sp., Ditylenchus sp. and Aphelenchus sp. ,Rhabditis sp. was found from compost and casing from all mushroom farms and the frequencies of Aphelenchoides sp. was 31.4% in the both compost and casing. Both Ditylenchus sp. and Aphelenchus sp. showed 2.7% of frequencies in the compost, none in casing. Temperature and moisture content of compost affected pathogenicity of Aphelenchoides sp. on mushroom mycelia grown in compost. The higher temperature and moisture content the sooner the damage became apparent, and the more rapid was subsequent destruction of mycelia. There was no mycelial destruction at the lowest temperature of $10^{\circ}C$. Rhabditis sp. completely disintegrated mycelia grown in the compost, in the early stage, the numbers of Rhabditis sp. rose gradually and then increased suddenly to reach a peak but soon declined. At first, the pH of Rhabditis-infested spawned compost declined but then rose gradually as mycelia was disintegrated by nematodes. The trend in pH of infested unspawned compost was similar to those of uninfested, unspawned compost. Cultures inoculated with surface-disinfected dead Rhabditis sp. and with tap water used in the nematode extraction procedures showed no mycelial injury associated microorganisms containing within or outside the nematodes even though added by artificial wounding of the mycelia. Cultures artificially wounded showed no injury away from the wounds without the presence of living Rhabditis sp., such wounded mycelia slowly regenerated. On the other hand, artificial wounding accelerated the breakdown of mycelia in the presence of living Rhabditis sp.