Florisil Column Chromatography Research Articles

Identification of a sex pheromone component of the Japanese mealybug, Planococcus kraunhiae (Kuwana)

A sex pheromone component of the Japanese mealybug, Planococcus kraunhiae, was isolated and identified. A crude extract of the pheromone obtained by airborne collection was first fractionated with Florisil column chromatography. The activity of each fractionated sample was examined in Petri dishes. The active fraction was further purified by HPLC and an active component was isolated by preparative GC. The purified compound showed attraction activity to adult males of P. kraunhiae in the field. The chemical structure was determined to be 2-isopropyliden-5-methyl-4-hexen-1-yl butyrate by GC-MS and NMR analyses.

PH조절 분배추출에 의한 식물체 중 Methoxyfenozide와 Bentazone의 HPLC 분석

이 연구는 액액분배과정 중 pH 조절에 의한 diacylhyazine계의 곤충생장조정(IGR)계 살충제 methoxyfenozide와 benzothiadiazinone계의 제초제 bentazone의 분배효율을 향상시키기 위하여 수행하였다. 현미시료는 두 약제 모두 "추출<TEX>$\rightarrow$</TEX>응고법<TEX>$\rightarrow$</TEX>분배추출<TEX>$\rightarrow$</TEX>florisil column chromatography"의 동일한 과정을 거쳤다. 볏짚시료에 있어서 methoxyfenozide는 "추출<TEX>$\rightarrow$</TEX>1 M-NaOH 용액에 의한 알칼리화<TEX>$\rightarrow$</TEX>분배추출<TEX>$\rightarrow$</TEX>응고법<TEX>$\rightarrow$</TEX>florisil column chromatography"의 과정을 거친 후 용리액인 acetonitrile : 20 mM sodium acetate(75:25, v/v)로 정용, HPLC로 분석하였다. Bentazone의 경우는 "추출<TEX>$\rightarrow$</TEX>1 M-NaOH 용액 첨가에 의한 알칼리화<TEX>$\rightarrow$</TEX>유기용매 세척<TEX>$\rightarrow$</TEX>12 M-HCl 의한 산성화<TEX>$\rightarrow$</TEX>분배추출<TEX>$\rightarrow$</TEX>florisil column chromatography"의 과정을 거쳤으며, acetonitrile : 75 mM sodium acetate(pH 6.0) (40:60, v/v)로 정용, HPLC로 분석 하였다. Methoxyfenozide의 회수율은 현미 83.5-97.4%, 볏짚 86.4-97.3%였으며, 분석법의 검출한계는 현미 0.02 mg/kg 볏짚 0.04 mg/kg이었다. Bentazone의 회수율은 현미 86.8-101.9 %, 볏짚 88.3-94.5%였으며, 분석법의 검출한계는 현미 0.005 mg/kg, 볏짚 0.01 mg/kg이었다. 본 연구결과에서 얻은 위 방법은 재현성 있는 안정적 분석조건을 제공한다는 점에서 두 약제의 잔류분석에 유용하게 적용될 수 있을 것으로 생각된다. This study was performed to enhance the cleanup efficiency of methoxyfenozide and bentazone by pH adjustment in the course of liquid-liquid partition and to develop an optimum analytical conditions using HPLC coupled with DAD for two matrices, brown rice and rice straw. Preparation procedure of brown rice sample was "extraction<TEX>${\rightarrow}$</TEX>coagulation<TEX>${\rightarrow}$</TEX>liquid-liquid partition<TEX>$\rightarrow$</TEX>-florisil C.C", and this procedure was samely applied to two compounds. In rice straw, preparation procedure of methoxyfenozide sample was "extraction<TEX>$\rightarrow$</TEX>-alkalization<TEX>$\rightarrow$</TEX>liquid-liquid extraction<TEX>$\rightarrow$</TEX>coagulation<TEX>$\rightarrow$</TEX>florisil C.C", and in the case of bentazone, "extraction<TEX>$\rightarrow$</TEX>alkalization<TEX>$\rightarrow$</TEX>liquid-liquid partition<TEX>$\rightarrow$</TEX>acidification<TEX>$\rightarrow$</TEX>liquid-liquid extraction<TEX>$\rightarrow$</TEX>florisil C.C". All these purified samples were redissolved in the mobile phases, acetonitile : 20 mM sodium acetate (75:25, v/v) for methoxyfenozide and acetonitrile : 75 mM sodium acetate, pH 6.0 (40:60, v/v) for bentazone. Recoveries of methoxyfenozide analysis in brown rice and rice straw were 83.5-97.4 and 86.4-97.3%, and detection limits were 0.02 and 0.04 mg/kg, respectively. Recoveries of bentazone in brown rice and rice straw were 86.8-101.9 and 88.3-94.5% and detection limits were 0.005 and 0.01 mg/kg, respectively. This methods seem to be usefully applied to the residue analysis of two compounds in the view of producing stable analytical condition and fair reproducibility.

Accumulation of Endosulfan in Wild Rat, Rattus norvegious as a Result of Application to Soya Bean in Mazoe (Zimbabwe)

An assessment of levels of endosulfan and endosulfan sulphate in rats collected from a plot sprayed with endosulfan was carried out for a period of four months. The analysis was carried out in the livers, muscles and fatty tissues of the rats using Gas Chromatography. Samples were ground with sodium sulphate and aluminium oxide and the analyte soxhlet extracted with hexane. The extract was then cleaned by florisil column chromatography. Levels of endosulfan in rats were found to range in livers from 0.356 to 5.807 ppb, in muscles from 0.089 to 5.167 ppb and in fatty tissues from 0.083 to 4.785 ppb. Levels of endosulfan sulphate correlated well with those of endosulfan and ranged in livers from 0.00 to 3.96 ppb, in muscles from 0.00 to 3.37 ppb and in fatty tissue from 0.00 to 2.93 ppb. In the control rats samples, collected from an unsprayed area in the city of Harare (University of Zimbabwe), no endosulfan could be detected.

Isolation and characterization of a novel uronic acid-containing acidic glycosphingolipid from the ascidian Halocynthia roretzi

A novel uronic acid-containing glycosphingolipid (UGL-1) was isolated from the ascidian Halocynthia roretzi. UGL-1 was prepared from chloroform-methanol extracts and purified by the use of successive column chromatography on DEAE-Sephadex, Florisil, and Iatrobeads. Chemical structural analysis was performed using methylation analysis, gas chromatography, gas chromatography-mass spectrometry, matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry, and 1H-NMR spectra. The chemical structure of UGL-1 was determined to be a glucuronic acid-containing glycosphingolipid, Galbeta1-4(Fucalpha1-3)GlcAbeta1-1Cer. The ceramide component was composed of C16:0 and C18:0 acids and C16-, C17-, and C18-phytosphingosines as major components.

Identification of the contact sex pheromone of Gastrophysa atrocyanea (Coleoptera: Chrysomelidae)

The mating behavior of the male Gastrophysa atrocyanea, that is, extrusion of the aedeagus, was elicited by the cuticular hydrocarbons on the surface of the female body. Males attempted to mate with a dummy treated with the female equivalent of the female elytra extracts. After fractionation of the elytra extracts by Florisil column chromatography and reverse phase high performance liquid chromatography, two fractions, consisting mainly of methylheptacosanes and methylnonacosanes were found to elicit the male mating behavior. These compounds, synthetic 9-methylheptacosane, 11-methylheptacosane, 9-methylnonacosane and 11-methylnonacosane, were contained in active fractions and showed high pheromonal activity. Therefore, these monomethylalkanes were considered to be contact sex pheromones of this beetle. However, synthetic 13-methylheptacosane, 13-methylnonacosane and 15-methylnonacosane, positional isomers of active monomethylalkanes, also contained in the active fractions, did not have the activity. A mixture of these seven monomethylalkanes at approximately natural concentrations also had enough activity to elicit the male mating behavior. Furthermore, the results of a bioassay using some related structural monomethylalkanes revealed that the length of the carbon backbone and the position of the methyl branch greatly influenced the pheromonal activity of G. atrocyanea.

High-Performance Liquid Chromatographic Determination of Cyclosulfamuron Residues in Soil, Water, Rice Grain and Straw

Analytical methods were developed to determine cyclosulfamuron residues in soil, water, rice grain and straw using high-performance liquid chromatography (HPLC) with ultraviolet absorption detection. In these methods, cyclosulfamuron was extracted with aqueous Na₂HPO₄/acetone and acetone/methanol mixture from soil and rice samples respectively. Liquid-liquid partition coupled with ion-associated technique, Florisil column chromatography, and solid-phase extraction (SPE) were used to separate cyclosulfamuron from interfering co-extractives prior to HPLC analysis. For water sample, the residue was enriched in C_(18)-SPE cartridge, cleaned up in situ, and directly subjected to HPLC. Reverse-phase HPLC under ion-suppression was successfully applied to determine cyclosulfamuron in sample extracts with the detection at its λ_(max) (254 nm). Recoveries from fortified samples averaged 87.8±7.1% (n=12), 97.3±7.2% (n=12), 90.8±6.6% (n=6), and 78.5±6.7% (n=6) for soil, water, rice grain and straw, respectively. Detection limits of the methods were 0.004 mg/kg, 0.001 mg/L, 0.01 mg/kg and 0.02 mg/kg for soil, water, rice grain and straw samples, respectively.

Ultraviolet Derivatization of Steroidal Saponin in Garlic and Commercial Garlic Products as p-Nitrobenzoate for Liquid Chromatographic Determination

A method is described for determination of the steroidal saponin, eruboside B, originating in garlic and garlic products as the p-nitrobenzoyl chloride (PNBC) derivative by reversed-phase liquid chromatography (with ultraviolet detection at 260 nm. Proto-eruboside B was extracted from garlic (Allium sativum L.); subjected to solid-phase extraction (SPE) with a C18 cartridge, Florisil column chromatography, and silica gel column chromatography; and then enzymatically converted to eruboside B, which was applied as an external standard. Steroidal saponins in garlic and commercial garlic products were extracted with methanol and purified by SPE cartridges, followed by enzymatic treatment. A frostanol saponin such as proto-eruboside B is enzymatically transformed to a spirostanol saponin, eruboside B. After the derivatization with PNBC, the saponin derivative was chromatographed on a C8 column with a gradient elution of (A) 80% aqueous acetonitrile and (B) 100% acetonitrile. The detection limit of the developed method was 1 microg/g for the samples. The method was applied to the analysis of garlic and garlic health food products available in Japan.

Detection of Radiation-Induced Hydrocarbons in Green, Black and Oolong Teas

Hydrocarbons induced by gamma-irradiation of green, black, and oolong teas were analyzed to determine whether the hydrocarbons can be used as markers for detecting post-irradiation of these teas. The samples were irradiated at 0, 2.5, 5, 7.5, and 10 kGy. Detection was attempted by extracting fat from the teas, separation of hydrocarbons with florisil column chromatography, and identification of hydrocarbons by gas chromatography-mass spectroscopy (GC-MS). Concentration of hydrocarbons increased with the irradiation dose. The major hydrocarbons in irradiated green, black, and oolong teas were 1-tetradecence (14:1), pentadecane (15:0), 1,7-hexadecadiene (16:2), 1-hexadecene (16:1), 8-heptadecene (17:1), and heptadecane (17:0). Radiation-induced hydrocarbons in teas were 1,7- hexadecadiene and 8-heptadecene. These compounds were not detected in non-irradiated samples, so the hydrocarbons (16:2, 17:1) can be used as markers for detecting post-irradiation of the teas. Furthermore, detection of hydrocarbons after 12 months storage at room temperature remains a suitable method for identifying irradiated teas.

Radiocarbon evidence for a naturally produced, bioaccumulating halogenated organic compound.

Halogenated organic compounds (HOCs) such as 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole (DBP-Br4Cl2) and heptachloro-1'-methyl-1,2'-bipyrrole (Q1) have been detected worldwide, sometimes at high levels in Antarctic air, seabird eggs, the blubber of marine mammals, and, most notably, even human milk. To date, it has been difficult to determine whether these compounds are natural products or derived from industrial synthesis. Molecular-level 14C analysis of these compounds is particularly appealing because most industrial compounds are manufactured from petrochemicals (14C-free) and natural compounds should have "modern" or "contemporary" 14C levels. To investigate the source of DBP-Br4Cl2, we isolated 600 microg of this compound (150 microg of carbon) from marine animal extracts by employing gel permeation chromatography, Florisil column chromatography, and two-dimensional preparative capillary gas chromatography. The purified DBP-Br4Cl2 was split into two samples (75 microg of carbon each) and analyzed by accelerator mass spectrometry for 14C content. The delta14C values were -449 percent per thousand and -467 percent per thousand, corresponding to conventional 14C ages of 4740 and 5000 years before present (BP), respectively. The presence of detectable 14C in the DBP-Br4Cl2 strongly points to at least a natural or biogenic source. However, these delta14C values for DBP-Br4Cl2 are more depleted than expected for a recently synthesized natural product. Several explanations are discussed, but additional samples

Solid phase extraction (SPE) method for detection of irradiated meats

Solid phase extraction (SPE) has been proposed as an alternative to the currently used florisil column chromatography. The hydrocarbons formed from beef, pork and chicken irradiated with 0–10 kGy were determined by the SPE and quantified by GC/MS. The limit of detection for the hydrocarbons in irradiated meats was 0.5 kGy. The correlation between the irradiation dose and the concentrations of hydrocarbons in beef, pork and chicken was high that linear regression coefficients ( r 2) were 0.87–0.99. SPE method would be used as the rapid detection of irradiated meats.

Analysis of Radiation-Induced Hydrocarbons and 2-Alkylcyclobutanones from Dried Shrimps (Penaeus aztecus)

We investigated the usefulness of hydrocarbons and 2-alkylcyclobutanones as markers for irradiated, dried shrimps. A method was developed to detect the irradiation of dried shrimps (Penaeus aztecus) by identifying radiation-induced hydrocarbons and 2-alkylcyclobutanones extracted from dried shrimps, which were separated by Florisil column chromatography and identified by a method using gas chromatography/mass spectrometry. Radiation-induced hydrocarbons and 2-alkylcyclobutanones are formed from the fatty acids of the irradiated fats. The quantity of the hydrocarbons and 2-alkylcyclobutanones formed from some fatty acids is related to the composition of fatty acids in a sample. The concentrations of hydrocarbons and 2-alkylcyclobutanones increased with radiation dose. The major hydrocarbons in the irradiated, dried shrimps were 1-tetradecene and pentadecane from palmitic acid; small amounts of heptadecane and 1-hexadecene from stearic acid; and 8-heptadecene and 1,7-hexadecadiene from oleic acid. 2-(5′-Tetradecenyl)cyclobutanone, one of the 2-alkylcyclobutanones, was present at the highest concentration. The radiation-induced hydrocarbons and 2-alkylcyclobutanones were detected at radiation doses of 0.5 kGy and greater. These compounds were not detected in nonirradiated, dried shrimps.

Effect of Culture Origin on Chemical Stimulation of Sexual Reproduction in Phytophthora and Pythium

Lecithin washed with NaCl solution was stimulatory to oospore formation of Phytophthora boehmeriae, P. sojae, P. cactorum, and Pythium aphanidermatum. Commercial glycerides of palmitic acid with 99% purity were found to contain a substance inhibitory to oospore formation. Purification with florisil column chromatography was more effective in removing the inhibitory substance than thin-layer chromatography or NaCl washing. After purification, monopalmitin, dipalmitin and tripalmitin were found to be stimulatory to the sexual reproduction of Phytophthora for the first time. These compounds were stimulatory to oospore formation of P. boehmeriae and P. sojae but not P. medicaginis, and were stimulatory to isolate S317 of P. sojae but not isolate CN-1 of the same species. Pythium aphanidermatum cultured on basal medium grew sparsely but steadily and produced oospores after being transferred to nutrient-free water agarose. Extracts from mycelia of P. boehmeriae, P. cactorum, and P. sojae grown in liquid basal medium were stimulatory to their own sexual reproduction. Results support the hypothesis that pythiaceous fungi can synthesize substances needed for sexual reproduction but require a stress factor to trigger the process.

Determination of Fenoxaprop-Ethyl in Agricultural Products by HPLC with Photometric Detection and Mass Spectrometry

A method was developed for the determination of 6-chloro-2,3-dihydrobenzoxazol-2-one (CDHB) generated by the acid decomposition of fenoxaprop-ethyl and fenoxaprop in agricultural products. Fenoxaprop-ethyl and fenoxaprop were extracted from agricultural products using acetonitrile, and the extract was acidified by 0.5 mol/l hydrochloric acid to make CDHB. The CDHB was extracted again into ethyl acetate and cleaned up using Sep-Pak® Plus Diol and Bond Elut® AccuCAT cartridge columns. The recoveries from brown rice, wheat, cotton seed, onion, carrot, sweet potato and cabbage exceeded 70% by HPLC (UV). However, soybean, green soybeans and kidney beans showed many interference peaks in the UV spectra, and Florisil column chromatography was necessary for additional purification. The fortified peaks were confirmed by liquid chromatograph/mass spectrometry (LC/MS) with electrospray ionization (ESI), and the CDHB peak was quantitatively determined. Almost the same result was obtained by HPLC (UV) and LC/MS selected ion monitoring (SIM). Consequently, for agricultural products which included many interfering peaks during UV detection, using LC/MS (SIM) significantly improved the quantitative and qualitative analyses and the number of interfering peaks was fewer than by UV detection.

건조 홍합의 방사선 조사여부를 확인하기 위한 지방분해산물 분석

건조된 홍합을 방사선 조사시켜 생성된 hydrocarbon류를 분리하기 위하여 Soxtec 기기를 이용하여 지방을 추출한 뒤, florisil column chromatography하였으며, GC/MS 분석기기로 성분을 확인하였다. 0.5～10 kGy의 선량별로 조사된 건조된 홍합에서 방사선 조사에 의해 생성된 hydrocarbon류 함량이 조사선량에 따라 증가하였으며, 동일한 선량으로 조사된 시료임 에도 방사선 조사에 의해 생성된 hydrocarbon류 각각의 함량이 다르게 정량되었다. 건조된 홍합의 방사선 조사에 의해 생성되는 hydrocarbon류와 2-alkylcyclobutanone류는 0.5 kGy 이상 조사된 시료에서 모두 검출되었으며, 비조사 시료에서는 검출되지 않았다.

Simultaneous determination of phthalate di- and monoesters in poly(vinylchloride) products and human saliva by gas chromatography–mass spectrometry

A gas chromatographic–mass spectrometric (GC–MS) method using selected ion monitoring (SIM) is described for the simultaneous determination of phthalate di- and monoesters in poly(vinylchloride) (PVC) products. The method consists of the following four procedures; (1) liquid–liquid extraction with ethyl acetate from the acidified aqueous homogenates of the PVC products, (2) esterification with trimethylsilyldiazomethane (TMSD) and methanol, (3) clean-up using Florisil column chromatography and (4) quantitative determination of methylated phthalate monoesters by GC–MS using SIM. The methylated monoesters show a characteristic mass fragment pattern at m/ z 163, 149 and 91. The calibration curves for the monoesters were linear from 0.05 to 10 ng (injection volume 1 μl). Overall recoveries ranged from 86.6 to 94.3%. The limits of detections for these methylated derivatives were in the range of 2.0–5.0 ng/g ( S/N=3). This method was applied to phthalate monoesters in PVC toy products. Mono- n-butyl phthalate and mono-2-ethylhexyl phthalate were found at levels of 6.42–11.62 μg/g and 30.50–41.81 μg/g, respectively. No monoethyl phthalate, mono- n-hexyl phthalate and monobenzyl phthalate were found in the toy products. The method was also applied to these compounds in human saliva.

Characterization of Phytochemicals Stimulatory to Sexual Reproduction in Phytophthora Cactorum and P. parasitica

Phytophthora cactorum and P. parasitica formed oospores on basal medium supplemented with corn oil or crude soybean lecithin. The non-saponifiable fraction from these two supplements were stimulatory to oospore formation of both fungi, but the saponifiables were stimulatory to only P. cactorum. When the non-saponifiables were subjected to Florisil column chromatography, the fraction eluted with 25% diethyl ether in hexane was the most stimulatory. Thin layer chromatography (TLC) separated this fraction into three active bands. Among them, the two non-digitonide TLC bands were further separated by high performance liquid chromatography (HPLC), and the active fractions were isolated for gas chromatography-mass spectrometry (GC-MS) analysis. Compounds identified were 3-eicosyne, β-farnesene, tetradecane (2, 6, 10-trimethyl), docosane, hexadecanol (2-methyl), phytol, and pentatriacontane. Commercially available phytol tested was found to be highly stimulatory to oospore formation of both fungi. It was active even at the concentration of 1 ng/basal medium disc.

Detection of alkanes and alkenes for identifying irradiated cereals

AbstractAlkanes and alkenes can be produced from lipids in maize, brown rice, and wheat by irradiation. The purpose of this study was to determine whether the detection pattern of the hydrocarbons can be used for identifying postirradiation of cereals. Maize, brown rice, and wheat were irradiated at 0.5, 1, and 3 kGy. Oils were extracted from the samples using hexane and anhydrous Na2SO4. Hydrocarbon‐containing fractions, isolated using Florisil column chromatography, were analyzed using gas chromatography (GC). The first six Florisil column chromatography fractions of 10 mL each were collected. Prominent radiation‐induced alkenes 17∶1, 16∶2, 17∶2, and 16∶3 appeared mainly in the third, fourth, and fifth fractions. Those three fractions were combined and evaporated to a total volume of 4 mL for GC analyses. Alkenes 17∶1, 16∶2, 17∶2, and 16∶3 were detected in all irradiated samples but not in the non‐irradiated ones. The levels of the hydrocarbons changed little by roasting the nonirradiated and irradiated cereals.

Hydrocarbons detected in irradiated and heat-treated eggs

Shell eggs were non-irradiated or irradiated at 0.5, 1 and 3 kGy, and boiled, fried or heated in ovens. Hydrocarbons were determined by a sequential procedure of lipid extraction by hexane, Florisil column chromatography and gas chromatography. Hydrocarbons 15:0, 14:1, 17:0, 16:1, 17:1, 16:2, 17:2 and 16:3 were detected in shell eggs irradiated at 0.5 kGy or higher, but not in non-irradiated ones except 15:0 and 17:0. Boiling non-irradiated or irradiated eggs for 40 min little affected detection levels of the hydrocarbons. Frying the egg yolk of the non-irradiated eggs for 5 min produced hydrocarbons 17:1 and 17:2 besides 15:0 and 17:0. Hydrocarbons 15:0, 17:0, 17:1, 17:2, 14:1 and 16:1 were detected in the egg yolk of the non-irradiated eggs while heating it in a cooking oven at 170°C for 60 min. The pattern of hydrocarbons detected in non-irradiated samples when heated was, however, notably different from that of irradiated ones; detection of hydrocarbons in shell eggs or egg products could, thus, identify their post-irradiation.

Detection of Radiation-Induced Hydrocarbons and 2-Alkylcyclobutanones in Irradiated Perilla Seeds

The method consists of the extraction of fat from perilla seeds, separation of hydrocarbons and 2-alkylcyclobutanones with florisil column chromatography, and identification of hydrocarbons and 2-alkylcyclobutanones by gas chromatography–mass spectroscopy (GC-MS). Concentrations of hydrocarbons and 2-alkylcyclobutanones increased with the irradiation dose. The major hydrocarbons in the irradiated perilla seeds were 8-heptadecene and 1,7-hexadecadiene from oleic acid and 6,9-heptadecadiene and 1,7,10-hexadecatriene from linoleic acid. One of the 2-alkylcyclobutanones, 2-(5′-tetradecenyl)cyclobutanone, was found in the highest concentration in the irradiated perilla seeds. Radiation-induced hydrocarbons in the perilla seeds were detected at doses of 0.5 kGy and higher, and radiation-induced 2-alkylcyclobutanones were detected at doses of 1 kGy and higher. These compounds were not detected in nonirradiated perilla seeds.

Hydrocarbons detected in irradiated shell eggs during storage

AbstractHydrocarbons produced by γ‐radiation of shell eggs were analyzed to determine how irradiation affects their production. Shell eggs were nonirradiated or irradiated at 0.5, 1, and 3 kGy and the stored at 5°C for 8 wk or at 30°C for 10 d. Hydrocarbons were determined by a sequential procedure of lipid extraction by hexane, Florisil column chromatography, and gas chromatography. Hydrocarbons C15:0, C14:1, C17:0, C16:1, C17:1, C16:2, C17:2, and C16:3 were detected in shell eggs irradiated at 0.5 kGy or higher, but not in nonirradiated ones except C15:0 and C17:0. Storage of nonirradiated or irradiated eggs had little effect on detection levels of hydrocarbons. The detection levels in all the samples irradiated at 1 and 3 kGy were in the order of C16:2+C17:1, C15:0+C14:1, C17:2+C16:3, and C17:0+C16:1 from the highest to the lowest.