Razzaghi-Abyaneh Mehdi, Shams-Ghahfarokhi Masoomeh, Yoshinari Tomoya, Rezaee Mohammad-Bagher, Jaimand Kamkar, Nagasawa Hiromichi, Sakuda Shohei
Department of Mycology, Pasteur Institute of Iran, Tehran 13164, Iran.
Int J Food Microbiol. 2008 Apr 30;123(3):228-33. doi: 10.1016/j.ijfoodmicro.2008.02.003. Epub 2008 Feb 15.
In an effort to screen the essential oils of some Iranian medicinal plants for novel aflatoxin (AF) inhibitors, Satureja hortensis L. was found as a potent inhibitor of aflatoxins B1 (AFB1) and G1(AFG1) production by Aspergillus parasiticus NRRL 2999. Fungal growth was also inhibited in a dose-dependent manner. Separation of the plant inhibitory substance(s) was achieved using initial fractionation of its effective part (leaf essential oil; LEO) by silica gel column chromatography and further separation by reverse phase-high performance liquid chromatography (RP-HPLC). These substances were finally identified as carvacrol and thymol, based on the interpretation of 1H and 13C NMR spectra. Microbioassay (MBA) on cell culture microplates contained potato-dextrose broth (PDB) medium (4 days at 28 degrees C) and subsequent analysis of cultures with HPLC technique revealed that both carvacrol and thymol were able to effectively inhibit fungal growth, AFB1 and AFG1 production in a dose-dependent manner at all two-fold concentrations from 0.041 to 1.32 mM. The IC50 values for growth inhibition were calculated as 0.79 and 0.86 mM for carvacrol and thymol, while for AFB1 and AFG1, it was reported as 0.50 and 0.06 mM for carvacrol and 0.69 and 0.55 mM for thymol. The results obtained in this study clearly show a new biological activity for S. hortensis L. as strong inhibition of aflatoxin production by A. parasiticus. Carvacrol and thymol, the effective constituents of S. hortensis L., may be useful to control aflatoxin contamination of susceptible crops in the field.
为了筛选一些伊朗药用植物的精油以寻找新型黄曲霉毒素（AF）抑制剂，发现庭荠（Satureja hortensis L.）是寄生曲霉NRRL 2999产生黄曲霉毒素B1（AFB1）和G1（AFG1）的有效抑制剂。真菌生长也受到剂量依赖性抑制。通过硅胶柱色谱对其有效部位（叶精油；LEO）进行初步分级，并通过反相高效液相色谱（RP-HPLC）进一步分离，从而实现了植物抑制物质的分离。基于对1H和13C NMR光谱的解析，最终将这些物质鉴定为香芹酚和百里香酚。在含有马铃薯葡萄糖肉汤（PDB）培养基的细胞培养微孔板上进行微生物测定（MBA）（28℃培养4天），随后用HPLC技术对培养物进行分析，结果表明香芹酚和百里香酚在0.041至1.32 mM的所有两倍浓度下均能以剂量依赖性方式有效抑制真菌生长、AFB1和AFG1的产生。香芹酚和百里香酚对生长抑制的IC50值分别计算为0.79和0.86 mM，而对于AFB1和AFG1，香芹酚的IC50值分别报告为0.50和0.06 mM，百里香酚的IC50值分别为0.69和0.55 mM。本研究获得的结果清楚地表明庭荠具有一种新的生物活性，即对寄生曲霉产生黄曲霉毒素有强烈抑制作用。庭荠的有效成分香芹酚和百里香酚可能有助于控制田间易感作物的黄曲霉毒素污染。
