• Journal of Microbiology and Biotechnology
• /
• v.12 no.3
• /
• pp.514-517
• /
• 2002

To investigate oleic acid biodegradation, 47 fungal strains were tested with modified Czapek Dox broth media containing oleic acid, and their biodegradative activities were assayed by measuring the release of $[^14C]CO_2$ from the $^14C-$labeled oleic acid. After 72 h of cultivation, Aspergillus flavus, Aspergillus ochraceus, and Alternaria species metabolized approximately $25\%\;to\;35\%$ of the supplied oleic acid. The relationship between the fungal degradation of oleic acid and the fungal growth was also examined using 7 strains of Aspergillus niger. A. niger. YMC 0100 and YMC 0322 degraded about $26\%$ of the oleic acid after 72 h, while their germination ratios were more than $30\%$.

• Journal of Food Hygiene and Safety
• /
• v.15 no.2
• /
• pp.122-127
• /
• 2000

An antifungal bacterium was isolated to inhibit of the growth of Asp. flavus and Asp. parasiticus, and its antifungal compounds were purified from lyophilized culture broth using chromatographic methods. Antifungal bacterium #19 which was shown a higher inhibitory activity on the growth of aflatoxin producing fungi was identified as Bacillus subtilis. The purified antifungal compound(1 mg) was demonstrated strong antifungal activity against the aflatoxin producing fungi.

• Mycobiology
• /
• v.36 no.4
• /
• pp.260-265
• /
• 2008

Cyclic voltammetric measurements were performed for Co(II), Ni(II), Cu(II) and Zn(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-succinic anhydride) (L) and Ni(II) and Cu(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-methacrylic acid) ($L^1$). The in vitro biological screening effects of the investigated compounds were tested against the fungal species including Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans and bacterial species including Staphylococcus aureus, Escherichia coli, Klebsiella pneumaniae, Proteus vulgaris and Pseudomonas aeruginosa by well diffusion method. A comparative study of inhibition values of the copolymers and their complexes indicates that the complexes exhibit higher antimicrobial activity. Copper ions are proven to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium. The nuclease activity of the above metal complexes were assessed by gel electrophoresis assay and the results show that the copper complexes can cleave pUC18 DNA effectively in presence of hydrogen peroxide compared to other metal complexes. The degradation experiments using Rhodamine B dye indicate that the hydroxyl radical species are involved in the DNA cleavage reactions.

• Journal of Food Hygiene and Safety
• /
• v.14 no.1
• /
• pp.55-59
• /
• 1999

6-(4-Iodophenyl)amino-7-chloro-5,8-quinolinedione (RCK9) was evaluated for antifungal activities. The MIC values of RCK9 were determined against A. flavus, c. albicans, C. neoformans and F. oxysporium. The RCK9 showed generally potent antifungal activities against the tested fungi. Acute oral toxicity studies of RCK9 were carried out in ICR mice of both sexes. These acute oral toxicities of RCK9 had been evaluated. RCK9 were low and LD50 values were over 2,850 mg/kg in ICR mice. The genotoxicities of RCK9 had been evaluated. RCK9 was negative in Ames test with Salmonella typhimurium and chromosomal aberration test in CHL cells. The clastogenicity was tested on the RCK9 with in vivo mouse micronucleus assay. RCK9 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. The results indicate that RCK9 has no genotoxic potential under these experimental conditions.

• Korean Journal of Food Science and Technology
• /
• v.1 no.1
• /
• pp.78-84
• /
• 1969

An attempt has been made to investigate the possible occurrence of aflatoxins, a group of micotoxin which are toxic metabolites produced by Aspergillus flavus, and aflatoxin like substances in fungal fermented soybean products such as meju and soybean paste. Chloroform extracts from 15 samples which has been defated with petroleum ether are subjected to separations with thin-layer chromatography on silica gel washed with methanol prior to film coating, improves the chromatographic separation and ultraviolet absorption spectral identification. In addition to fluorescencing spot having an Rf value which is same as aflatoxin $B_1$, many of the fluorescencing spots have been occurred in every sample examined. Each fluorescencing spot is scratched and the ethanol extracts are subjected to further separation with thin-layer chromatography. Each fluorescence substance is eluted with ultra violet transparent absolute ethanol and the ultraviolet absorption spectra are checked. None of the absorption curve of eluates shsow accordance with the curve of aflatoxin. 2, 4-Dinitrophenyl hydrazine reagent, Tollen's reagent and ninhydrin reagent are applied on the chromatogram- The data show that aflatoxin is not present in any of the fungal preparations examined.

• Mycobiology
• /
• v.39 no.4
• /
• pp.278-282
• /
• 2011

The objective of this study was to find useful fungi with ${\alpha}$-amylase activity from the Korean traditional nuruk for the quality of traditional Korean alcoholic beverage. In this study, 165 samples of traditional nuruk were collected from 170 regions throughout Korea and the fungi were isolated to a total of 384 strains. In order to investigate the effect of microflora on nuruk, ${\alpha}$-amylase activity, saccharogenic power (SP), starch hydrolysis activity and acid producing activity were evaluated. Ten strains were selected by ${\alpha}$-amylase activity, which ranged from 458.47 to 1,202.75 U/g. The size of the discolored zone for the starch hydrolysis activity of each fungus ranged from 0.3 to 2 cm. The SP of the 10 strains ranged from 228.8 to 433.4 SP. Of the 10 stains, three were identified as Aspergillus oryzae, two as Aspergillus flavus, two as Lichtheimia sp., one as Rhizopus oryzae and two as other strains. The total aflatoxins present in the nuruks were examined using enzyme-linked immunosorbent assay. The 10 nuruks had less than 1.11 ppb of aflatoxins.

• Mycobiology
• /
• v.37 no.2
• /
• pp.141-146
• /
• 2009

Novel copper(II) complexes have been synthesized from the macrocyclic Schiff bases derived from Knoevenagel condensed ${\beta}$-ketoanilides (obtained by the condensation of acetoacetanilide and substituted benzaldehydes), 4-aminoantipyrine and ophenylene diamine. The structural features have been determined from their analytical and spectral data. All the Cu(II) complexes exhibit square planar geometry. Their high molar conductance values support their 1 : 2 electrolytic nature. The magnetic moment data provide evidence for the monomeric nature of the complexes. The X-band ESR spectra of the |$CuL^1$|$(OAc)_2$ in DMSO solution at 300 and 77 K were recorded and their salient features are reported. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by well diffusion method. A comparative study of inhibition values of the Schiff bases and their complexes indicate that complexes exhibit higher antimicrobial activity than the Schiff bases. Copper ions proved to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium.

• Mycobiology
• /
• v.35 no.2
• /
• pp.47-53
• /
• 2007

The prevalence and population density of the mycobiota of 50 samples belonging to 10 kinds of spices (anise, black pepper, red pepper, black cumin, peppermint, cardamom, clove, cumin, ginger and marjoram) which collected from different places in Jeddah Governorate were studied. The natural occurrence of mycotoxins in those samples was also investigated. Fifteen genera and thirty-one species of fungi in addition to one species variety were isolated and identified during this study. The most common genera were Aspergillus, Penicillium and Fusarium. Aflatoxins ($12{\sim}40\;{\mu}g/kg$) were detected in the extract of 5 samples of each of anise seeds and black pepper fruits; three samples of black cumin seeds and on sample only of each of peppermint and marjoram leaves out of 5 samples tested of each. Sterigmatocystin ($15{\sim}20\;{\mu}g/kg$) was detected in some samples of red pepper, cumin and marjoram. The inhibitory effects of 10 kinds of powdered spices were tested against 3 toxigenic isolates of fungi (Aspergillus flavus, A. versicolor and Penicillium citrinum). Clove proved to be antimycotic compounds. It inhibited the growth of the tested toxigenic fungi. Black pepper, peppermint, cardamom, cumin and marjoram completely inhibited aflatoxins production, while black pepper and cardamom also completely inhibited sterigmatocystin production.

• Preventive Nutrition and Food Science
• /
• v.15 no.3
• /
• pp.233-238
• /
• 2010

The aim of this study was to determine microbiological contamination of fresh-red pepper and packaged-red pepper powder commercially available in South Korea. Thirty-seven fresh-red peppers were collected from 5 farms and 31 packaged-red pepper powders were purchased from retail markets in South Korea. Foodborne pathogens (Escherichia coli, Salmonella spp., Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus), total viable counts, Enterobacteriaceae, coliforms, yeast and mold, and Aspergillus flavus were determined. Detection percentage of contamination of Bacillus cereus in fresh-red pepper was 8.1%, which was lower than the 39% of detection rate in packaged-red pepper powder. The contamination level of Bacillus cereus was 1～3 log CFU/g in packaged-red pepper powder. Escherichia coli was detected in 5.4% of fresh-red pepper samples and was not detected in packaged-red pepper powder. Enterobacteriaceae and coliforms were detected in both of fresh-red pepper and packaged-red pepper powders. Foodborne pathogens, except Bacillus cereus and Escherichia coli, were not detected.

• Natural Product Sciences
• /
• v.13 no.4
• /
• pp.279-282
• /
• 2007

The aim of the present study was to investigate the various chemical components present in the cone volatile oil of Cupressus macrocarpa and also determine its antimicrobial activity. Totally 13 compounds were identified with 99.99% by GC-MS analysis. The major compounds identified were terpinene-4-ol (19.42%), dinopol (15.63%), ${\alpha}$-pinene (13.58%), and ${\beta}$-pinene (12.16%). The antimicrobial activity was carried out for the oil and a 2% cream formulation using cup plate method by measuring the zone of inhibition. The gram positive organisms used were Bacillus subtilis, Staphylococcus aureus, Bacillus megaterium, and Bacillus cogulans. The gram negative organisms used were Escherichia coli, Kleibseilla pneumonia, Pseudomonas aeruginosa and Salmonella typhi. In vitro antifungal studies were also carried out by using organisms, Candida albicans, Aspergillus flavus, Trichoderma lignorum and Cryptococcus neoformans. The standard drugs used were penicillin ($100{\mu}g/mL$), gentamycin ($100{\mu}g/mL$) and griseofulvin ($100{\mu}g/mL$) for gram positive bacteria, gram negative bacteria and fungi respectively. Both oil and cream formulation showed good activity against fungi than bacteria. This study is being reported for the first time on cone volatile oil of this plant.