Identification of goose (Anser anser) and mule duck (Anasplatyrhynchos x Cairina moschata) foie gras by multiplex polymerase chain reaction amplification of the 5S RDNA gene.

Polymerase chain reaction (PCR) amplification of the nuclear 5S rDNA gene has been used for the identification of goose and mule duck foie gras. Two species-specific reverse primers were designed and used in a multiplex reaction, together with a forward universal primer, to amplify specific fragments of the 5S rDNA in each species. The different sizes of the species-specific amplicons, separated by agarose gel electrophoresis, allowed clear identification of goose and mule duck foie gras samples. This genetic marker can be useful for detecting fraudulent substitution of the duck liver for the more expensive goose liver.     

Freshness and quality criteria of iced farmed Senegalese sole (Solea senegalensis)

Senegalese sole (Solea senegalensis) is a high-value commercial species with increasing importance in aquaculture. The aim of this work was to study the quality changes of this species during chilled storage under refrigeration, through sensory and chemical methods. In particular, the optimization of a quality index method (QIM) scheme was proposed as well as the definition of sensory and chemical quality criteria. A shelf life of 15 days was reported, and a QIM scheme based on a total of 22 demerit points (dp) was proposed. Biogenic amines were never detected, and the usual spoilage indicators, such as TVB-N and TMA-N, were not significantly produced during the period of sensory-acceptable quality (15 days). On the basis of the significant correlations (p<0.001) between sensory data and Ki values, a quality index (QI) 19 dp and a Ki>40% indicate unacceptable quality of iced Senegalese sole.     

Bacterial 16S rDNA sequences in immature volcanic ash soil on volcanoes Mt. Sakurajima and Mt. Fugen in Japan determined by PCR amplification

Volcanogenous soils are widely distributed in Japan. Andosols, a group of volcanogenous soil, are known to show several physicochemical characteristics such as high porosity, presence of allophane, and high content of organic carbon (FitzPatrick 1980). The formation of Andosols is a very rapid process resulting from the large surface area of the volcanic ash-derived parent materials.     

柑桔黄龙病病原16S rDNA克隆、测序及实时荧光PCR检测方法的建立

克隆并测定了中国柑桔黄龙病病原16SrDNA基因序列，经同源性比较，表明属于柑桔黄龙病菌(Liberobacter asiaticum)亚洲种中一个新株系(中国厦门株系)。依据获得的16SrDNA特异序列，建立了柑桔黄龙病病菌检测的实时荧光PCR方法，并应用此方法对柑桔样品进行了检测。结果显示，该检测方法具有快速、特异、敏感、重复性好等优点。该方法为柑桔黄龙病的检测，特别是早期诊断、检疫和病害的综合治理奠定了基础。     

Design and evaluation of nematode 18S rDNA primers for PCR and denaturing gradient gel electrophoresis (DGGE) of soil community DNA

Consensus nematode 18S ribosomal DNA primers were designed by aligning available 18S sequences and identifying a variable region flanked by highly conserved regions. These primers were then used to amplify nematode 18S rDNA from whole soil community DNA extracted from a range of European grassland types. Cloning of the PCR amplicons (778 bp) followed by restriction digest analysis (RFLP) resulted in the recovery of 34 unique nematode sequences from the four grasslands studied. Comparison of these data with the limited number of 18S rDNA nematode sequences currently held in on-line databases revealed that all of the sequences could be assigned to known nematode taxa albeit tentatively in some cases. Two of the sequences recovered from the site in the Netherlands (wet, hay-grassland) were recovered in a clade that included a sequence of the genus Trichodorus whilst other sequences from this site showed similarity with 18S rDNA sequences of the genus Prismatolaimus (five sequences), Xiphinema (one sequence) and Enoplus (one sequence). Of the remaining sequences, two showed some affinity with Mylonchulus (UK, upland peat), four with Steinernema (UK) and one sequence with Mesorhabditis (Hungary, east European Steppe). Three sequences from the Netherlands and one from Hungary were recovered in a clade that included a sequence of the genus Pratylenchoides whilst three further sequences from the Netherlands and two from Hungary were recovered in a clade encompassing the genus Globodera. Of the remaining nine sequences, two (NL6, NL62) formed a distinct lineage within the Adenophorea with 90% bootstrap recovery in a paraphyletic clade that included sequences of Prismatolaimus and Trichodorus. Seven sequences (three from the Netherlands, three from the UK and one from Greece) were left unassigned though the tree topology suggested some relationship (58% bootstrap recovery) with the genus Cephalobus. To assess whether primers used to amplify 18S rDNA might be used to fingerprint genetic diversity in nematode communities in soil, the environmental sequence data were used to design a second set of primers carrying a GC-clamp. These primers amplified a 469 bp fragment internal to the region flanked by the primer set used to derive the nematode trees and were used to amplify 18S rDNA for subsequent analysis using denaturing gradient gel electrophoresis (DGGE). DGGE analysis of six major European grassland types revealed considerable genetic diversity between sites. However, the relationships seen with the DGGE data were inconsistent with previous studies where the same soils had been characterized with respect to functional and morphological diversity. To confirm that this second set of primers was amplifying nematode sequences, selected bands on the DGGE gels were extracted, PCR amplified and sequenced. The final alignment was 337 bases. These analyses revealed the presence of sequence signatures from the genera Paratrichodorus, Plectus, Steinernema, Globodera, Cephalobus and Pratylenchoides.     

热不对称PCR(TAIL-PCR)和Tn5转座子质粒拯救法快速分离水稻条斑病菌致病相关基因

构建植物病原菌突变体库是进行新基因发掘和功能基因组学研究的有效途径之一.为快速准确地鉴定Tn5的插入位点和相应的功能基因,研究采用热不对称PCR(TAIL-PCR)和Tn5转座子质粒拯救两种技术,鉴别了在筛选水稻条斑病菌(Xanthomonas oryzae pv.oryzicola)Tn5插入突变体库过程中获得的8个在水稻(Oryza sativa)上毒性减弱的突变体.结果显示,TAIL-PCR和Tn5质粒拯救结合使用,可有效地鉴别Tn5的插入位点和相应的功能基因.TAIL-PCR鉴别的5株突变体是Tn5分别插入在分泌系统结构蛋白F基因(gspF)、cAMP调控蛋白、膜镶嵌蛋白酶酶原、S-蛋硫氨酸脱羧酶亚基和gspJ基因上;Tn5质粒拯救法鉴别的3株突变体是Tn5分别插入在致病性蛋白、功能未知的保守蛋白和鞭毛特异性ATP合酶基因上.序列同源性分析发现,8株突变体Tn5插入的基因与基因组测序的BLS256菌株中的对应基因同一性达100%.这表明,TAIL-PCR和Tn5质粒拯救技术可有效地应用于植物病原菌Tn5突变体库的鉴别和目标基因的分离.     

Identification of Chinese alligators (Alligator sinensis) meat by diagnostic PCR of the mitochondrial cytochrome b gene

With the commercial farming and exploitation of Chinese alligators (Alligator sinensis), illegal and inappropriately labeled Chinese alligator meat has appeared in markets. To prevent the illegal hunting and commerce for Chinese alligators, it will be important to develop an expedient and practical method for the identification of Chinese alligator meat. In this study, a pair of the species-specific PCR primers (Alli-M and Alli-R) was designed using sequence variations of mitochondrial DNA (mtDNA) cytochrome b gene between Chinese alligators and other crocodilians. By the multiplex PCR of using the species-specific primers and 12S rRNA universal primers L1091 and H1478, 31 samples (27 meat samples, 4 skin samples) were identified. The result of amplification displayed that only the fresh and the cooked meat samples from the Chinese alligator could be amplified with two bands. We also present a case of identification of a crocodilian body part found in a local market using the newly developed primers. The specific primers designed in this study could be widely used for the rapid and accurate identification of not only alligator meat but also other commercial products from Chinese alligator.     

PCR技术在快生型大豆根瘤菌菌株鉴别上的应用

以基因外重复的回文因子（ｒｅｐｅｔｉｔｉｖｅｅｘｔｒａｇｅｎｉｃｐａｌｉｎｄｒｏｍｉｃ，ＲＥＰ）和肠杆菌基因间重复一致序列（ｅｎｔｅｒｏｂａｃｔｅｒｉａｌｒｅｐｅｔｉｔｉｖｅｉｎｔｅｒｇｅｎｉｃｃｏｎｓｅｎｓｕｓ，ＥＲＩＣ）的碱基顺序设计出的引物为引物，用ＰＣＲ（ｐｏｌｙｍｅｒａｓｅｃｈａｉｎｒｅａｃｔｉｏｎ）技术分别扩增了８株快生型大豆根瘤菌（Ｓｉｎｏｒｈｉｚｏｂｉｕｍ）的总ＤＮＡ，得出了具有菌株特异性的扩增产物电泳图谱，称ＲＥＰ－ＥＲＩＣＰＣＲ指纹图谱，将所得图谱进行性状编码后，用计算机数值分类系统进行平均连锁聚类分析，得出这８个菌株的聚类树状图。这一聚类结果与用其它方法聚类结果基本一致，说明ＲＥＰ－ＥＲＩＣＰＣＲ是一种鉴别快生型大豆根瘤菌菌株的经济、快速而又可靠的新方法。     

Identification of the razor clam species Ensis arcuatus, E. siliqua, E. directus, E. macha, and Solen marginatus using PCR-RFLP analysis of the 5S rDNA region

Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis of the 5S ribosomal DNA region has been applied to the establishment of DNA-based molecular markers for the identification of five razor clam species: Ensis arcuatus, E. siliqua, E. directus, E. macha, and Solen marginatus. PCR amplifications were carried out using a pair of universal primers from the coding region of 5S rDNA. S. marginatus was simply distinguished by the different size of the amplicons obtained. Species-specific restriction endonuclease patterns were found with the enzymes Hae III for E. arcuatus, E. siliqua, and E. directus, and Acs I for E. macha, and when two enzymes were combined, the four species were also identified. Thus, this work provides a simple, reliable, and rapid protocol for the accurate identification of Ensis and Solen species in fresh and canned products, which is very useful for traceability and to enforce labeling regulations.     

Identification of gadoid species in fish meat by polymerase chain reaction (PCR) on genomic DNA

Identification of fish species is significant due to the increasing interest of consumers in the meat of sea fish. Methods focusing on fish species identification help to reveal fraudulent substitution among economically important gadoid species in commercial seafood products. The objective of this work was to develop a conventional PCR method for the differentiation of the following gadoid fish species in fish products: Alaska pollack ( Theragra chalcogramma), blue whiting ( Micromesistius poutassou), hake spp. ( Merluccius spp.), Atlantic cod ( Gadus morhua), saithe ( Pollachius virens), and whiting ( Merlangius merlangus). The species-specific primer pairs for gadoid species determination were based on the partial pantophysin I ( PanI) genomic sequence. Sequence identification was confirmed by cloning and sequencing of the PCR products obtained from the species considered. For the simultaneous detection of Alaska pollack, blue whiting, and hake spp., a quadruplex PCR system was constructed. Other gadoid species were detected in separate PCR reactions. After optimization of the reactions, the developed PCR systems were used for the analysis of codfish samples obtained from the Czech market and the customs' laboratories. This method represents an alternative approach in the use of genomic DNA for the identification of fish species. This method is rapid, simple, and reliable without the need for further confirmative methods. Furthermore, the identification of a mixture of more than one species is possible. The PCR system has been optimized for routine diagnostic purposes.     

The 5S rRNA gene sequence variation in wheats and some polyploid wheat progenitors (Poaceae: Triticeae)

We have cloned and sequenced 115 repeat units of the 5S rDNA genes and spacers from wheat (Triticum) and the polyploid wheat progenitor, Aegilops, and analyzed them together with sequences available in GenBank® (National Center for Biotechnology Information, NCBI, NLM, NIH, Bethesda, Maryland, USA). We were able to assort the sequences into nine orthologous groups which we call unit classes. The following unit classes were assigned to haplomes, and labeled accordingly: long A1, short A1, short A2, long G1, short G1, long D1, short D1, long S1 and short S1. The AA-genome, DD-genome and SS-genome species were each found to contain a long and a short class. The AAGG-genome species T. timopheevii and the AAA^tA^tGG-genome species T. zhukovskyi, both contain the long A1, long G1 and short G1 unit classes. The AABB-genome species T. turgidum consists of the short A2, a unit class not yet found in T. monococcum, and the long S1 unit class found in the species of Aegilops section Sitopsis. The bread wheat AABBDD-genome contains the long A1, short A2, long D1, long S1 and short G1 unit classes. The presence of the long S1, also demonstrated to occur in both T. turgidum and T. aestivum, supports the hypothesis that the progenitor of the B-haplome in wheat originated in Aegilops section Sitopsis. The presence of the short G1 unit class, i.e. the G-haplome in bread wheat, is unexpected. These new findings are discussed in the light of published findings, especially those relating to 5S DNA loci and evolutionary hypotheses.     

Karyotype characterization reveals an up and down of 45S and 5S rDNA sites in <Emphasis Type="Italic">Crotalaria</Emphasis> (Leguminosae-Papilionoideae) species of the section Hedriocarpae subsection Macrostachyae

The genus Crotalaria is one of the largest within the family Leguminosae-Papilionoideae, with more than 600 species. However, few karyotypes have been described. In the present paper, five species belonging to the section Hedriocarpae were studied (subsection Machrostachyae), in order to better understand chromosomal evolution in Crotalaria. The results reveals that all species presented 2n = 2x = 16 with symmetrical karyotypes, and slight differences in the chromosome morphology. A secondary constriction was identified at short arm of the pair 1. The 45S rDNA was mapped in the secondary constriction and adjacent heterochromatin (NOR-heterochromatin) and a minor site was identified in C. ochroleuca. The 5S rDNA was mapped linked to 45S rDNA at chromosome 1 short arm in all species. Additional sites for 5S rDNA were identified in C. pallida, C. striata and C. mucronata. Heterochromatin blocks around the centromeres are not CMA⁺ neither DAPI⁺. The karyotypes of the subsection Macrostachyae are characterized by an inversion at chromosome pair one in relation to previous specialized floral species analyzed. Additional sites of 45S and 5S rDNA were assumed to be a result of transposition events by different ways. The results suggest heterochromatin differentiation and the position of ribosomal genes indicates chromosomal rearrangements during evolution. Karyotype characteristics corroborate the morphological infrageneric classification.     

Estimating N2 fixation by Sesbania rostrata and S. cannabina (syn. S. aculeata) in lowland rice soil by the 15N dilution method

Summary A field experiment in concrete-based plots was conducted to estimate the contribution of N derived from air (Ndfa) or biological N₂ fixation in Sesbania rostrata and S. cannabina (syn. S. aculeata), using various references, by the ¹⁵N dilution method. The two Sesbania species as N₂-fixing reference plants and four aquatic weed species as non-N₂-fixing references were grown for 65 days after sowing in two consecutive crops, in the dry and the wet seasons, under flooded conditions. Soil previously labeled with ¹⁵N at 0.26 atom % ¹⁵N excess in mineralizable N was further labeled by ammonium sulfate with 3 and 6 atom % ¹⁵N excess. The results showed that ¹⁵N enrichment of soil NH ₄ ⁺ -N dropped exponentially in the first crop to half the original level in 50 days while in the second crop, it declined gradually to half the level in 130 days. The decline in ¹⁵N enrichment, in both N₂-fixing and non-fixing species, was also steeper in the first crop than in the second crop. Variations in ¹⁵N enrichment among non-fixing species were smaller in the second crop. The ratio of the uptake of soil N to that of fertilizer N in N₂-fixing and non-fixing species was estimated by the technique of varying the ¹⁵N level. In the second crop, this ratio in non-fixing species was higher than that in N₂-fixing species. Comparable estimates of % Ndfa were obtained by using ¹⁵N enrichment of various non-fixing species. There was also good agreement between the estimates obtained by using ¹⁵N enrichment of non-fixing species and those by using soil NH ₄ ⁺ -N, particularly in the second crop. By 25 days after sowing, the first crop of both Sesbania spp. had obtained 50% of total N from the atmosphere and the second crop had obtained 75%. The contribution from air increased with the age of the plant and ranged from 70% to 95% in 45–55 days. S. rostrata fixed substantially higher amounts of N₂ due to its higher biomass production compared with S. cannabina. Mathematical considerations in applying the ¹⁵N dilution method are discussed with reference to these results.     

Biotransformation of (R)- and (S)-terpinen-4-ol by the larvae of common cutworm (Spodoptera litura)

(R)-Terpinen-4-ol was mixed in an artificial diet at a concentration of 1 mg/g of diet, and the diet was fed to the last instar larvae of common cutworm (Spodoptera litura). Metabolites were recovered from frass and analyzed spectroscopically. (R)-Terpinen-4-ol was transformed mainly to (R)-p-menth-1-en-4,7-diol. Similarly, (S)-terpinen-4-ol was transformed mainly to (S)-p-menth-1-en-4,7-diol. The C-7 position (allylic methyl group) of (R)- and (S)-terpinen-4-ol was preferentially oxidized.     

水牛促卵泡素受体(FSHR)基因5''''端侧翼序列的克隆与分析

促卵泡素(FSH)是动物脑垂体分泌作用于卵巢卵泡生长、发育、分化、成熟和排卵的重要繁殖激素.由于是生物大分子,不能透过细胞膜,FSH必须与靶细胞膜上的促卵泡素受体(FSHR)结合,经过受体介导将信息传递到靶细胞内,才能发挥其生物学功能.目前国内外已对牛、山羊等多种动物的FSHR基因的Cdna序列进行了克隆测序,但是关于水牛FSHR基因5'端侧翼序列还未见报道.本研究对水牛FSHR基因5'端序列进行克隆和序列分析,其目的是寻找水牛FSH受体基因的SNP突变位点,从而为以后进行FSH受体基因的多态性分析和探索该受体基因在水牛繁殖中的可能作用打下基础.     

The origin of the A genome donor of wheats (Triticum: Poaceae) – a perspective based on the sequence variation of the 5S DNA gene units

In a prior study on the haplomes of wheat using the 5S rRNA gene we assigned the long A1 and short A1 unit classes to the A haplome in the diploid T. monococcum. The short A1 unit class is absent in the tetraploids T. turgidum and T. timopheevii and in the hexaploid T. aestivum, although present in the hexaploid T. zhukovskyi. Both T. turgidum and T. aestivum contained a different 5S DNA unit class labeled the short A2.The purpose of this paper was to study the short A2 units in the two diploid species to shed light on the theory that the A haplome donor of T. turgidum and T. aestivum was T. urartu. Fifty eight clones were obtained from 12 accessions, sequenced and analyzed. As expected T. baeoticum, which is often classified as a subspecies of T. monococcum, contained the long A1 and the short A1 5S DNA units. Unexpectedly, T. urartu had the long A1 and the short G1 unit classes instead and other units not found so far in Triticum. These findings support the hypothesis that the donor of the A genome in T. zhukovskyi was T. monococcum, as identified by the short A1 units. However, the short A1 units are absent in T. timopheevii, also a carrier of the A genome. The short G1 units found in T. urartu also identify it as a possible donor of the G genome to T. timopheevii. The short G1 units were also found in T. aestivum in our prior study. The long G1 unit class was not found in T. urartu but reported from T. timopheevii and T. zhukovskyi. The implications of these and related findings on the evolution of wheats are discussed.     

Human-altered and human-transported (HAHT) soils in the U.S. soil classification system

ABSTRACT

Human-altered and human-transported (HAHT) soils are widespread across the globe and are concentrated near where people live and work. Although some of the HAHT soils are significant because they can be hazardous to human, animal, and plant health, most are not mapped or classified to the same extent as agricultural soils. The purpose of this article is to discuss the occurrence, types, and importance of HAHT soils and to document the historical and proposed classification of HAHT soils in Soil Taxonomy. There are two main forms of materials that define HAHT soils: human-altered soils formed in human-altered materials (HAM) from the soil surface to 50 cm (or to bedrock if shallower) or more and human-transported soils formed in human-transported materials (HTM) from the soil surface to 50 cm (or to bedrock if shallower) or more. The HAHT soils mainly occur in urban areas, transportation corridors, mined lands, landfills, filled shallow water, and agricultural areas on anthropogenic landforms. Hazards include danger from radioactivity, pollution, content of hazardous artifacts, or presence on unstable landforms that may fail during heavy rains or earthquakes. The HAHT soils are extensive, and their extent is growing. In the past, few HAHT soils were described or classified adequately because the U.S. Soil Taxonomy system was established for agricultural and other naturally occurring soils. However, HAHT soils are now being recognized and classified in many soil classification systems at very high levels. A new soil order is proposed for U.S. Soil Taxonomy that would include the most obvious profoundly and intentionally altered HAHT soils. A discussion and justification is given for an unofficial proposal. Input will be collected from international groups of scientists, and modifications of the unofficial proposal are expected. The long-term result of establishing a new soil order will be to enable proper classification, allocation, and mapping of HAHT soils worldwide.     

传染性胃肠炎病毒(TGEV)双启动子真核表达载体pVAXD-N/S的构建与鉴定

猪传染性胃肠炎(TGE)是由猪传染性胃肠炎病毒(TGEV)引起的高度接触性传染病.TGEV的S、N基因具有重要的免疫学功能,构建S、N双基因疫苗将能提供更好的免疫效果.本研究用RT-PCR扩增S基因抗原区(2.1 kb,含A、B、C和D完整的抗原位点)和N基因编码区(1.2 kb),分别定向插入双启动子真核表达载体pVAXD的多克隆位点(MCS),构建了单价质粒pVAXD-N和pVAXD-S,然后将N基因插入pVAXD-S中,构建了双启动子真核表达质粒pVAXD-N/S.将pVAXD-N/S与对照组(pVAXD-N、pVAXD-S和pVAXD)转染COS-7细胞进行表达鉴定,用RT-PCR可从pVAXD-N/S转染细胞中扩增出s、N两个目的基因,IFA鉴定结果显示,pvAXD-N/S可同时表达S、N两种目的蛋白.初步的小鼠(Mus musculus)免疫试验结果显示,pVAXD-N/S免疫小鼠后第14天即可检测到抗TGEV的IgG抗体,第35天抗体达最高峰,pVAXD-N/S诱导的抗体水平显著高于单基因质粒组pVAXD-N和pVAXD-S的抗体水平(P＞0.5),与混合质粒(pVAXD-N+pVAXD-S)诱导的抗体水平相当.本研究结果表明,构建的双启动子表达载体pV AXD-N/S具有S、N基因的双重免疫功能,为TGEV新型双基因疫苗研究提供了基础材料.     

Identification and Characterization of U.S. Wheats Carrying Null Alleles at the wx Loci

Granule-bound starch synthase (GBSS) is the primary enzyme responsible for the synthesis of amylose in amyloplasts of cereal endosperm cells. Bread wheats, due to their hexaploid genetic system, carry three genes (wx loci) encoding GBSS. Purification and separation of GBSS from more than 200 North American hexaploid wheats allowed the identification of genotypes that carry null alleles at either the wx-A1 and wx-B1 loci. In addition, the cultivar Ike carried both wx-A1 and wx-B1 null alleles. No wx-D1 nulls were detected. Null alleles were found in 10% of the hard winter wheats tested, but in only 2% of the sampled soft winter wheats. Amylose contents of wheats carrying single null alleles at either the wx-A1 or wx-B1 loci often were lower than those of wild type wheats, but greater reduction in amylose content was observed in Ike. Monoclonal antibodies were used to quantify water-extractable GBSS in both wild-type and null genotypes. Gene dosage compensation was evident, although GBSS content, as measured by ELISA, was significantly lower in Ike than in all other wheats. The identification of null alleles in adapted genotypes suggests the development of wheats with a wide range of amylose contents will be possible by simple genetic crossing and selection.     

Biotransformation of (S)-(+)-linalool by Aspergillus niger: an investigation of the culture conditions.

The biotransformation of (S)-(+)-linalool by different Aspergillus niger strains was studied, using submerged shaken liquid cultures. One strain, A. niger DSM 821, was able to convert the substrate to cis- and trans-furanoid linalool oxide (yield 30% and 5%, respectively) and cis- and trans-pyranoid linalool oxide (yield 14% and 1.5%, respectively). The main metabolites, cis-(2S,5R)-furanoid and cis-(3S,6S)-pyranoid linalool oxide, have a sweet, floral, creamy odor and are used in perfumery. The culture conditions involved, such as the composition of the broth and the type and concentration of cosolvent applied and possible adaptation to the substrate during inoculation, were investigated. It was found that (S)-(+)-linalool was converted much better than (R)-(-)-linalool and that no significant chemical conversion of the substrate occurred in control flasks at pH 3.5. Three cosolvents for improving the solubility of linalool in the culture broths were compared, namely MeOH, EtOH, and acetone. The highest bioconversion yields were obtained when the substrate was applied as a diluted solution in acetone. Screening of the fungi for their biotransformation capacity was performed by solid-phase microextraction.