In this study, flavored oils were developed using oak mushroom (Lentinula edodes), with olive, avocado, soybean, and sunflower oils as the carrier oils. Changes in oxidative stability, color, aroma, and taste resulting from infusion with oak mushroom powder were then comparatively evaluated. Across all four oils, the samples infused with oak mushroom powder did not exhibit significant differences in primary and secondary oxidation levels compared with those of the controls; however, in terms of color, browning decreased in olive oil but tended to increase in avocado, soybean, and sunflower oils. Based on the analysis of aromatic characteristics, major sulfur compounds derived from oak mushroom formed in refined soybean and sunflower oils, whereas olive and avocado oils did not exhibit distinct effects. In terms of taste characteristics, umami increased after oak mushroom powder infusion across all oils, and the enhancement of umami was particularly significant in olive and avocado oils. These results indicate that the aromatic and taste characteristics of oak mushroom-flavored oils exhibit different patterns depending on the type of vegetable oil used.

Alternative substrate materials for mushroom cultivation must be developed due to the unstable supply of the currently used substrates. Threonine acts as a nitrogen source in the substrate used for cultivating mushrooms. Threonine influences food flavor and participates in lipid metabolism and protein synthesis as well as energy metabolism through the tricarboxylic acid cycle. In this study, mushroom cultivation substrate was supplemented with threonine to evaluate the effects of threonine on the growth characteristics of and secondary metabolites produced by Pleurotus ostreatus. Threonine supplementation induced substantial changes in the parameters indicating the quality of fruiting bodies. These findings provide a basis for further research on supplementing substrates with amino acids for cultivating mushrooms.

This study evaluated the effects of supplementing sawdust medium with 10% (w/w) Korean-style soy sauce residue (KS) and brewed soy sauce residue (BS) on the cultivation of Pleurotus ostreatus. Over 25 days, KS treatment produced mycelial growth comparable to the control, whereas BS treatment showed slower colonization. Fruiting bodies appeared after nine days in the control, ten days with BS, and twelve days with KS, with fresh weights of 146.0 g, 174.8 g, and 89.0 g, respectively, indicating reduced yield with KS and increased yield with BS. In antioxidant assays, DPPH radical scavenging slightly increased from 89.15% in the control to 89.99% with KS and 90.34% with BS. ABTS scavenging was 82.36% in the control, 83.42% with KS, and 75.99% with BS. Total polyphenol content was 64.39 mg AAE/mL in the control, 62.72 mg AAE/mL with KS, and 43.28 mg AAE/mL with BS. In conclusion, KS supports mycelial growth without compromising DPPH-based antioxidant capacity, while BS enhances fruiting body yield but reduces ABTS activity and phenolic content. Both residues show potential as supplementary nutrients in conventional sawdust media.

선박용 프로펠러는 선박 추진 성능과 연비에 직접적인 영향을 미치는 핵심 부품으로, 제작 과정에서 높은 정밀도가 요구된다. 사형주조는 복잡한 형상의 금속 부품 제작에 널리 사용되는 공정이지만, 주조 과정에서 발생하는 열적 팽창과 냉각 수축은 최종 치수 오 차와 가공 비용 증가를 초래하는 주요 원인이다. 본 연구에서는 사형주조 과정에서 발생하는 열팽창 및 수축 현상을 정밀하게 예측하고, 이를 고려한 최적의 치수 여유 설정을 통해 연마 작업을 최소화하는 설계 방안을 제안하였다. 알루미늄 청동 합금(ALBC3)을 사용한 프로 펠러를 대상으로 열팽창 공식과 유한요소해석(FEM)을 적용하여 블레이드, 허브, 전체 지름 등 각 부위별 변형을 정량적으로 분석하였다. 분석 결과, 블레이드 너비와 두께는 약 1.9%, 허브 직경은 1.5%, 전체 지름은 2.0%의 여유를 두는 것이 적절한 것으로 나타났다. 이러한 최 적 치수 여유를 적용한 결과, 최대 23kg의 재료 절감, 30만 원 이상의 제작 비용 절감, 작업 시간 50~60% 단축 등의 정량적 개선 효과가 확인되었다. 최적 설계를 적용함으로써 추가 연마 작업과 재료 손실을 줄일 수 있으며, 이에 따른 비용 절감 효과도 기대된다. 본 연구 결 과는 선박용 프로펠러 제작 과정의 품질 향상과 생산성 제고에 기여할 수 있을 것으로 판단된다.

In this study, we investigated the microbial community of oyster mushrooms at different growth stages at the species level. Gram-positive bacteria were predominant in the presterilized medium. On the other hand, Gram-negative bacteria were predominant in the culture-completed medium, post-harvest medium, and fruiting bodies. In addition, Pseudomonas tolaasii, which is known to cause disease in mushrooms, was confirmed in the cultured medium, post-harvest medium, and fruiting bodies, and it was determined that the mycelium culture stage was contaminated, and the reason why no disease occurred was Sphingobacterium psychroaquaticum. It was confirmed that this was because the growth of Pseudomonas tolaasii was suppressed by producing a component called tolacin. As a result of confirming the diversity of microorganisms, it was confirmed that the presterilization medium contains a variety of microorganisms compared to other growth stages, and the diversity decreases in the order of culture completion medium, fruiting body, and post-harvest medium. showed a trend. As a result of microbial similarity analysis, it was confirmed that the cultured medium and the post-harvest medium showed similar microbial communities, and in the case of fruiting bodies, there were some similarities but overall differences.

This study analyzed the effects of different nitrogen sources in substrate composition on the growth of Pleurotus ostreatus, as well as the subsequent changes in flavor and antioxidant activity. The T2, composed of poplar sawdust, beet pulp, cotton seed dregs, and cotton seed coat in a ratio of 40:20:20:20, exhibited the highest yield at 156.6 g. The total polyphenol content and ABTS and DPPH radical scavenging activities were 8.25 mg GAE/g, 70%, and 49%, respectively, showing higher radical scavenging activity compared to the Control and T1. Additionally, varying nitrogen content resulted in distinct aroma patterns and is presumed to influence taste profiles such as sourness, umami, and saltiness.

In this study, we examined the effects of gamma irradiation dosage on the mycelial growth of Auricularia auriculajudae and performed analyses of fruiting body yield, growth characteristics, taste, fragrance, and mineral composition. Assessments of mycelial growth in response to gamma irradiation at different intensities revealed an enhancement in the growth of fungi exposed to irradiation at 200 Gy. Fruiting body yield was also highest at 200 Gy, followed by 800 Gy and the control group. On the basis of these observations, we subsequently applied gamma ray doses of 200 and 800 Gy to examine the effects of irradiation on fungal quality characteristics. In terms of the taste of fruiting bodies, we detected no significant differences among the control, 200 Gy, and 800 Gy groups. Contrastingly, with respect to fragrance, we found that fungi treated with 200 Gy were characterized by a pattern that differed from those of the control and other treatment groups. Furthermore, whereas we detected no significant difference among treatments with respect total dietary fiber content, calcium content was found to be higher in the treatment groups compared with the control group, with the highest content being measured in fungi exposed to 800 Gy irradiation. Copper content was confirmed to be higher in the control group, whereas there were no significant differences between the fungi irradiated with 200 and 800 Gy. Contrastingly, the highest levels of zinc were detected in response to 200 Gy irradiation, followed by 800 Gy. Collectively, our findings thus indicate that gamma irradiation can contribute to promoting increases in the fruiting body yield and mineral contents of mushrooms.

A new brown variety of Flammulina velutipes, referred to as ‘Asakgold,’ was bred by crossing two monokaryons isolated from the “Geumhyang2ho” and “Garlmoe” varieties. The pileus color of the new variety is light brown and its shape is hemispherical. During bottle cultivation, the period necessary for mycelial growth was 40 days, 9 days for primordia formation and 15 days for fruiting body growth. The total cultivation period was 64 days, which was similar to that of the control variety “Yeoreumhyang1ho.” The pileus of the new variety was similar and the stipe was thinner and longer than that of the control. The number of valid stipes per bottle was 495, which was 37 % higher than that of the control (362), and the yield was 214 g, 16 % higher than that of the control (185 g). The -glucan content was 28.69 %, which was observed to be 1.6 times more than that of the control.

In this study, the growth characteristics of Lentinula edodes were confirmed by bean sprout waste(BW) as an alternative raw material for rice bran. The mycelium growth of Sanjo701, a major cultivation variety of L. edodes, was compared between a medium mixed with 8:2(v/v) of oak sawdust and a medium mixed with BW 50% and BW 100%. The mycelium growth in BW 50% was 13.5 cm. Compared to the control, BW 50% increased the diameter of the pileus by 1.6 cm. Additionally, the length of the pileus decreased by 0.4 cm when comparing the growth of the fruit body. In contrast, at BW 50%, the diameter of the pileus decreased by 9.6 cm and the length of the stipe decreased by 1.4 cm. According to analysis of the constituent amino acids, BW 50% showed a lower overall nutritional content than the control, whereas BW 100% had a lower amino acid content than the control. However, glutamic acid and aspartic acid, which are flavor-enhancing ingredients, were observed at levels of 3.954 mg/g and 1.436 mg/g, respectively, in BW 100%. Therefore, if bean sprout by-products are efficiently processed and utilized, it is believed that they will be beneficial to farmers as a substitute for rice bran and reduce the cost of manufacturing substrate

A new dark brown variety of Flammulina velutipes, referred to as ‘Asakchoco’, was bred by crossing two monokaryons isolated from the ‘Yeoreumhyang2ho’ and ‘Guemhyang2ho’ varieties. The pileus color of the new variety is dark brown and the stipe color is ivory, with uniformity from the upper section to the base. In addition, the primordia formation is uniform compared to that of the control, and the advantage of this is that the pileus does not become deformed after the primordia formation. During bottle cultivation, the period necessary for mycelial growth was 40 d, for primordia formation was 8 d, and for fruiting body growth was 16 d. The total cultivation period was 64 d, which was 2 d shorter than that of the control. The pileus was smaller and thicker and the stipe diameter was the same, but the stipe length was longer than that of the control. The number of valid stipes per bottle was 441, 24% higher than that of the control (357), and the yield was 197 g, 19% higher than that of the control (166 g).

In this study, we aimed to compare the mycelial growth of Pleurotus ostreatus after medium supplementation with various amino acids at different concentrations to select the optimal medium nutrient composition for mycelial growth. The mycelial growth of P. ostreatus was investigated after adding four amino acids (tryptophan, threonine, methionine, and lysine) at 0.5% or 1% to the medium.The rate of P. ostreatus mycelial growthwas faster in the potato dextrose agar (PDA) medium supplemented with threonine at 0.5% or 1% than that of the control, whereas it was inhibited by tryptophan treatment. Supplementation of sawdust mediumwith all amino acids, except tryptophan, at 0.5% did not alter the mycelial growth, compared to the controls. However, addition of any amino acid to sawdust medium at a higher concentration (1%) inhibited the mycelial growth. The laccase acitivity of P. ostreatus mycelium cultured in PDA medium was the highest when threonine was added, and the lowest when tryptophane was added, consistent with the results of the mycelial growth. Therefore, the addition of threonine, methionine, or lysine to PDA medium at a concentration of 0.5-1%was effective for increasing the mycelial growth of P. ostreatus; however, it inhibited mycelial growth insawdust medium, suggesting that the effects of amino acids dependedon the medium nutrient composition.

This study investigated the culture characteristics of Cryptoporus volvatus, whichis grow naturally in Korea, to determine the suitable environmental conditions for its cultivation. The physiological characteristics of the mycelia were assessed according to the cultivation conditions, to determine the optimal conditions for artificial cultivation. The visual characteristics of the hyphae of Cryptoporus volvatus KACC52303 included an irregular and uneven surface and a fuzzy or cotton-like texture. Under the microscope, its microstructure showed pre-chlamydospore formation, but no clamps were seen. The appropriate culture temperature was found to be a medium/high temperature of approximately 25–30oC, and the optimal pH was found to have a wide range from weakly acidic (pH 4) to neutral (pH 7). In the optimal nutrient source experiment, hyphal growth was shown to be fair in a mixed medium with 2.5% dextrin as the carbon source and 0.1% yeast extract as the organic nitrogen source. Among the various amino acids, organic acids, and inorganic salts tested, the fastest hyphal growth was observed in the presence of leucine, acetic acid or gluconic acid, and KCl or KH2PO4, respectively. The column test showed that the best mycelial growth occurred in a mixed medium of 80% pine sawdust, 10% rice bran, and 10% corncob sawdust.

This study was conducted to investigate the growth and antioxidant activity of Pleurotus ostreatus mycelia grown in medium supplemented with Aronia. The diameter and dry weight of the mycelia were increased in the medium supplemented with Aronia compared with the untreated medium. The total polyphenol content of mycelia grown in medium supplemented with Aronia and untreated medium was 6.54 mg GAE/g and 5.77 mg GAE/g, respectively. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of mycelia grown in medium supplemented with Aronia and untreated medium was 61.81% and 49.65%, respectively. Moreover, the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity of mycelia grown in medium supplemented with Aronia and untreated medium was 59.83% and 52.66%, respectively. These results confirmed that P. ostreatus mycelial growth and antioxidant activity were increased when Aronia was added to the culture medium.