• Research in Plant Disease
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• v.11 no.2
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• pp.185-192
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• 2005

In 1999 and 2002, 130 and 258 isolates of Colletotrichum spp. causing red pepper anthracnose were obtained from infected red pepper fruits, respectively. Their responses to 4 protective and 3 ergosterol biosynthesis-inhibiting(EBI) fungicides were investigated by observing their mycelial growth on PDA incorporated with different concentrations of each fungicide. The Colletotrichum isolates obtained in 1999 showed higher $EC_{50}$ values than those isolated in 2002 against three protective fungicides such as dithianon, chlorothalonil, and propineb, whereas the response was reversed toward other protective fungicide, iminoctadine. On the other hand, the isolates of year 1999 were more resistant against three EBI fungicides such as tebuconazole, hexaconazole, and prochloraz than those of year 2002; the $EC_{50}$ values of the former were 1.2-4.4 times higher than those of the latter, The responses of the Colletotrichum isolates toward protective and EBI fungicides were fluctuated according to regions, where the infected fruits were collected. On the other hand, the resis tance of Colletotrichum isolates to protective fungicides increased during monitoring from July to September, However, their responses towards EBI fungicides were not changed.

• YAKHAK HOEJI
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• v.43 no.2
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• pp.169-172
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• 1999

The acivity-guided fractionation on the MeOH extract of Bombycis corpus inoculated by Beauberia bassiana 101A led to the isolation of two steroids, 24-ethycholest-4-ene-3,6-dione (1) ergosterol peroxide (2), as active principles. Compounds 1 and 2 exhibited cytotoxicity against cultured human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT-15 with ED50 values ranging from 3.42 to $11.37{\;}\mu\textrm{g}/m$.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.282-288
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• 2006

Activity-guided fractionations led to the isolation of antitumor compound, ergosterol peroxide ($5{\alpha},\;8{\alpha}-epideoxy-24(R)-methylcholesta-6,\;22-dien-3{\beta}-ol$) from the fruiting body of Pleuratus eryngii that was cultivated artificially. This sterol structure was established by using spectroscopic methods ($^1H\;and\;^{13}C$ nuclear magnetic resonance and high resolution mass spectra). The purified compound showed a molecular formular of $C_{28}H_{44}O_3$ displaying characteristic features of epidioxy sterols. The 50% inhibitory concentrations ($IC_{50}$) of ergosterol peroxide against human lung cancer cell line (A549) and human ovarian cell line (SK-OV3) were $7{\mu}M\;and\;14{\mu}M$, respectively. In the DNA fragmentation assay, the compound showed the programmed cell death causing the chromosomal DNA fragmentation. It reveals that ergosterol peroxide arrests G1 phase of the cell division cycle.

• BMB Reports
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• v.30 no.5
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• pp.370-377
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• 1997

A novel assay method is described for rapid quantitation of reaction rate of sterol ${\Delta}^7$-reductase (${\Delta}^7$-SR) which catalyzes reduction of the ${\Delta}^7$-double bond of sterols. Of six different organ tissues-liver, small intestine, brain, lung, kidney, and testis-. ${\Delta}^7$-SR activity was detected only in liver (2.30 nmol/min/mg protein) and testis (0.11 nmol/min/mg protein). Using a newly developed method which employs diet-induced enzyme proteins and ergosterol as substrate, we assessed both kinetics ($K_m=210\;{\mu}M$, $V_{max}=1.93\;nmol/min/mg$) and inhibition of the rat hepatic ${\Delta}^7$-SR against well-studied cholesterol lowering agents such as triparanol ($IC_{50}=16\;{\mu}M$). 3-$\beta$-[2-(diethylamino)ethoxy]androst-5-en-17-one (U18666A) ($IC_{50}=5.2\;{\mu}M$), and trans-1.4-bis(2-chlorobenzylaminomethyl)cyclohexane dihydrochloride (AY-9944) ($IC_{50}=0.25\;{\mu}M$). Of the three well-known AY-9944-sensitive cholesterogenic enzymes (i.e., ${\Delta}^7$-SR, sterol ${\Delta}^8$-isomerase, and sterol ${\Delta}^14$-reductase). ${\Delta}^7$-SR was found to be the most sensitive enzyme with a noncompetitive inhibition of this compound ($K_i=0.109\;{\mu}M$). Substrate specificity studies of the microsomal ${\Delta}^7$-SR indicate that the relative reaction rate for 7-dehydrocholesterol and ergosterol are 5.6-fold and 1.6-fold higher than that for lathosterol. ${\Delta}^7$-SR activity was also modulated by feeding rats a diet supplemented with 0.5% ergosterol (>2.6-fold) in addition to 5.0% cholestyramine plus 0.1% lovastatin ($\simeq$5.0-fold). Finally, microsomal ${\Delta}^7$-SR was solubilized by 1.5% 3-[3-(cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CHAPS) and enriched on PEG (0~10%) precipitation, which should be suitable for further purification of the enzyme.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.828-831
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• 2005

The content of vitamin $D_2$, including its precursor ergosterol, was determined in some cultivated mushrooms to manufacture fortified Doenjang (Korean traditional soybean paste) with vitamin D by supplementation with mushroom. Ergosterol was the most abundant sterol in the mushrooms (50 to 140 mg/100 g dry weight) but the ergocalciferol portion made up only 0.065% (Pleurotus eryngii) to 2.5% (stipe part of Lentinus edodes, shiitake) of the total vitamin $D_2$ of each mushroom. Changes in these compounds in L. edodes caused by UV or solar irradiation were also evaluated. Ergocalciferol content in the pileus part of L. edodes went up to $424\;{\mu}g/100\;g$ dry weight and ergosterol levels reached 139.3 mg per 100 g dry weight at maximum levels. Ergocalciferol content increased about 50% when exposed to solar radiation and increased 377% with UV irradiation. These compounds level in Doenjang was enriched as much as supplied UV irradiated L. edodes powder to before fermentation, and the supplemented mushroom did not influence the palatability of Doenjang.

• Mycobiology
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• v.47 no.2
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• pp.242-249
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• 2019

Betaine derivatives are considered major ingredients of shampoos and are commonly used as antistatic and viscosity-increasing agents. Several studies have also suggested that betaine derivatives can be used as antimicrobial agents. However, the antifungal activity and mechanism of action of betaine derivatives have not yet been fully understood. In this study, we investigated the antifungal activity of six betaine derivatives against Malassezia restricta, which is the most frequently isolated fungus from the human skin and is implicated in the development of dandruff. We found that, among the six betaine derivatives, lauryl betaine showed the most potent antifungal activity. The mechanism of action of lauryl betaine was studied mainly using another phylogenetically close model fungal organism, Cryptococcus neoformans, because of a lack of available genetic manipulation and functional genomics tools for M. restricta. Our genome-wide reverse genetic screening method using the C. neoformans gene deletion mutant library showed that the mutants with mutations in genes for cell membrane synthesis and integrity, particularly ergosterol synthesis, are highly sensitive to lauryl betaine. Furthermore, transcriptome changes in both C. neoformans and M. restricta cells grown in the presence of lauryl betaine were analyzed and the results indicated that the compound mainly affected cell membrane synthesis, particularly ergosterol synthesis. Overall, our data demonstrated that lauryl betaine influences ergosterol synthesis in C. neoformans and that the compound exerts a similar mechanism of action on M. restricta.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.52-57
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• 2004

Seven compounds were isolated from stationary cultured mycelia of Inonotus obliquus, of which several of them showed certain antitumor activities. Seven compounds were identified as lanosterol(1), inotodiol(2), trametenolic acid(3), 3β,22,25-trihydroxy-lanosta-8-ene(6), 3β,22-dihydroxy-lanosta-8,24-diene(A), 3β-hydroxy- lanosta-8,24-dien-21-al(B) and methyl trametenolate(C), respectively. The precursor compound of sclerotium obtained from shaking-cultured and stationary-cultured mycelia of Inonotus obliquus is lanosterol. Ergosterol and ergosterol peroxide were obtained by shaking-culture, and the substituted compounds of C-21 and C-22 of lanosterol were obtained by stationary culture.

• The Korean Journal of Food And Nutrition
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• v.36 no.2
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• pp.129-136
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• 2023

In order to investigate the optimal UVB (ultraviolet B) treatment conditions for vitamin D₂ enhancement of freeze-dried ear mushroom, sample size (below 300 ㎛~whole), UV treatment temperature (30~60℃), treatment density (6.25~50.0 mg/cm²) and the samples mixing frequency (1~32 times) were treated differently. After that, chromaticity, vitamin D₂ and ergosterol (vitamin D₂ precursor) contents were investigated. As a result of the investigating, effective UVB treatment conditions for vitamin D₂ enhancement are as follows. The sample sizes were 2~4 mm and finely crushed pieces. The treatment temperatures were 50℃ and 60℃. The treatment density was 12.5 to 25.0 mg/cm², and the number of sample mixing was 8 times or more. As the amount of vitamin D₂ increased by UVB treatment, the ergosterol content generally tended to decrease. However, under some UVB treatment conditions, the vitamin D₂ content was not high despite the decrease of ergosterol content. Under the conditions set in this experiment, it was possible to obtain ear mushrooms with enhanced vitamin D₂ up to 26,968.7 ㎍/100 g. Therefore, it is thought that the ear mushroom is highly likely to be used as a vitamin D source and nutritionally fortified food ingredient.

• Journal of Applied Biological Chemistry
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• v.56 no.2
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• pp.109-112
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• 2013

Azole fungicides are one of the most wide-spread antifungal compounds in agriculture and pharmaceutical applications. Their major mode of action is the inhibition of ergosterol biosynthesis, giving depletion of ergosterol, precursors and abnormal steroids. However, metabolic consequences of such inhibition, other than steroidal metabolitesare not well established. Comprehensive metabolic profiles of Saccharomyces cerevisiae has been presented in this study. Wild type yeast was treated either with glucose as control or azole fungicide (ketoconazole). Both polar metabolites and lipids were analyzed with gas chromatography-mass spectrometry. Approximately over 180 metabolites were characterized, among which 18 of them were accumulated or depleted by fungicide treatment. Steroid profile gives the most prominent differences, including the accumulation of lanosterol and the depletion of zymosterol and ergosterol. However, the polar metabolite profile was also highly different in pesticide treatment. The concentration of proline and its precursors, glutamate and ornithine were markedly reduced by ketoconazole. Lysine and glycine level was also decreased while the concentrations of serine and homoserine were increased. The overall metabolic profile indicates that azole fungicide treatment induces the depletion of many polar metabolites, which are important in stress response.

• Natural Product Sciences
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• v.20 no.2
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• pp.76-79
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• 2014

In our ongoing search for structurally interesting and biologically active metabolites from Korean wild mushrooms, bioassay-guided fractionation and a chemical investigation of the MeOH extracts of the fruiting bodies of the mushroom Naematoloma fasciculare resulted in the isolation of three ergosterol derivatives, (22E,24R)-ergosta-7,22-diene-$3{\beta}$,$5{\alpha}$,$6{\beta}$,$9{\alpha}$-tetrol (1), (22E,24R)-$5{\alpha}$,$8{\alpha}$-epidioxyergosta-6,22-diene-$3{\beta}$-ol 3-O-${\beta}$-$\small{D}$-glucopyranoside (2), and (22E,24R)-$5{\alpha}$,$8{\alpha}$-epidioxyergosta-6,9,22-triene-$3{\beta}$-ol 3-O-${\beta}$-$\small{D}$-glucopyranoside (3). The structures of 1 - 3 were determined by comparison of their spectroscopic and physical data with reported values. The isolated steroid derivatives 1 and 3 were reported for the first time from this mushroom. Compounds 1 - 3 were tested for their cytotoxic activities against four human cancer cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15).