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- Odor Aversion and Pathogen-Removal Efficiency in Grooming Behavior of the Termite Coptotermes formosanus
Aya Yanagawa, Nao Fujiwara-Tsujii, Toshiharu Akino, Tsuyoshi Yoshimura, Takashi Yanagawa and Susumu Shimizu. PLoS One. 2012; 7(10): e47412. doi: 10.1371/journal.pone.0047412
<< Read Abstract >>
Abstract:
The results of biocontrol with entomopathogens in termites have been discouraging because of the strong social hygiene behavior
for removing pathogens from termite colonies. However, the mechanism of pathogen detection is still unclear. For the successful
application of biopesticides to termites in nature, it would be beneficial to identify substances that could disrupt the termite's
ability to perceive pathogens. We hypothesized that termites can perceive pathogens and this ability plays an important role in
effective hygiene behavior. In this study, pathogen-detection in the subterranean termite Coptotermes formosanus was investigated.
We performed quantitative assays on conidia removal by grooming behavior using epifluoresence microscopy and Y-maze tests to
examine the perception of fungal odor by termites. Three species each of high- and low-virulence entomopathogenic fungi were
used in each test. The results demonstrated that termites removed conidia more effectively from a nestmate's cuticle if its
odor elicited stronger aversion. Highly virulent pathogens showed higher attachment rates to termite surfaces and their odors
were more strongly avoided than those of low-virulence isolates in the same species. Moreover, termites appeared to groom each
other more persistently when they had more conidia on their bodies. In brief, insect perception of pathogen-related odor seems to
play a role in the mechanism of their hygiene behavior.
- Determination of breath gas composition of lung cancer patients using gas chromatography/mass spectrometry with monolithic material sorptive extraction
Wen Ma, Peng Gao, Jun Fan, Yuki Hashi, and Zilin Chen. Biomedical Chromatography, Volume 29, Issue 6, pages 961-965, June 2015
<< Read Abstract >>
Keywords:
volatile organic compounds; benzene series; gas chromatography/mass spectrometry; monolithic material sorptive extraction
Abstract:
A gas chromatographic-mass spectrometric method with monolithic material sorptive extraction (MMSE) pretreatment was
developed to determine the breath gas composition in lung cancer patients. MonoTrap silica monolithic and hybrid adsorbent
was selected as the extraction medium during MMSE, given its strong capacity to extract volatile organic compounds (VOC) from
exhaled gas. Under the appropriate conditions, high extraction efficiency was achieved. Using the selected ion-monitoring mode,
the limit of detection (signal-to-noise ratio 3) for the benzene series was 0.012-2.172 ng L¯1. The limit of quantitation (
signal-to-noise ratio, 10) was 0.042-7.24 ng L¯1. The linearity range of the method was 4-400 ng L¯1. Average recovery of the
benzene series at lower concentrations was 65-74% (20 ngL¯1). The relative standard deviation of benzene series contents
determined within the linear range of detection was <10% of the mean level determined. Our proposed method is simple,
rapid and sensitive, and can be competently applied to determine the breath gas composition of lung cancer patients.
- A study of the suppression of body odour in elderly subjects by anti-fungal agents
C. Ozeki and O. Moro. International Journal of Cosmetic Science, Volume 38, Issue 3, pages 312-318, June 2016
<< Read Abstract >>
Keywords:
anti-fungal agents; body odour; claim substantiation in vivo/in vitro; formulation hair + body care; squalene oxidation
Abstract:
Objective
The suppression of body odour following the use of shampoos or soaps containing the anti-fungal agent miconazole nitrate (MCZ)
has been recognized anecdotally. To determine whether MCZ could play a role in the suppression of body odour through
inhibiting squalene oxidation.
Methods
A prospective study recruited 54 elderly subjects residing in a nursing facility who needed bathing assistance.
Subjects bathed with three types of body soap over a 6-week study period (regular soap, sample soap (soap containing MCZ),
control soap; 2 weeks per type of soap). Body odour was evaluated based on olfactory assessment of the subjects and their clothing.
The subjects and the examiners were blinded to the type of soap (sample or control) being used during the study.
An analysis using GC/MS was also carried out to identify the volatile compounds associated with body odour.
- Determination of Chiral Jasmonates in Flowers by GC/MS after Monolithic Material Sorptive Extraction
Wen Ma, Shuai Fu, Yuki Hashi, and Zilin Chen. J. Agric. Food Chem., 2013, 61 (26), pp 6288-6292 | DOI: 10.1021/jf401104g
<< Read Abstract >>
Keywords:
chiral separation; endogenous jasmonates; gas chromatography/mass spectrometry; jasmonic acids; monolithic material sorptive
extraction
Abstract:
A GC/MS method with monolithic material sorptive extraction (MMSE) pretreatment was developed to determine contents of the
enantiomers of jasmonic acid and methyl jasmonate in flowers. To optimize MMSE extraction, several MMSE parameters were
investigated, including extraction temperature, extraction time, and extraction solvent. Under the optimal conditions,
extraction efficiency was good. Using the selected-ion monitoring mode, the limit of detection (LOD, S/N = 3) for methyl
jasmonates was 0.257 ng/mL. The limit of quantitation (LOQ, S/N = 10) was 0.856 ng/mL. The linearity range was 1-100 ng/mL.
The average recovery of methyl jasmonate at lower concentration was 116.8% (2 ng/mL). The relative standard deviation of methyl
jasmonate contents determined within the linear range of detection was less than or equal to 15% of the mean determined level.
The proposed method is rapid, sensitive, and competently applied to the determination of jasmonic acid and methyl jasmonate
enantiomers in flowers.
- Characterization of key odor compounds in steamed Chinese mitten crab (Eriocheir sinensis) farmed in Chongming
region by monolithic material sorptive extraction-gas chromatography-olfatometry and odor activity value methods.
Gu SaiQi; Wu Na; Zhang JingJing; Ji SiRu; Tao NingPing; Wang XiChang. Journal of Food Safety and Quality 2014 Vol.5 No.3 pp.877-888 ref.23
<< Read Abstract >>
Abstract:
Objective: To analyze the volatile compounds in different edible parts of steamed male E. sinensis farmed in Chongming region,
select the key odor compounds (KOCs) from all the volatiles, and finally offer some theoretical basis to explain its
outstanding flavor. Methods: Seven adsorption rods made of Mono-Trap RCC18 were applied to extract the volatile compounds
of 5 g crab sample under 100°C for 50 min under a headspace extraction mode. Those volatiles of crab samples were then
separated and identified by GC-MS and quantified by an internal standard method. In order to select the KOCs from all the
volatiles, a combination of GC-O and OAV methods were also employed. Results: A total of 71 volatiles were finally
identified in male E. sinensis farmed in Chongming region, among which 50, 48, 52 and 60 volatiles were identified in the
abdomen, claw, leg meat and the gonad part, respectively. 19 KOCs were successfully selected from all 71 volatiles.
Among them, 6 main key odor compounds (MKOCs). With an odor intensity value (OIV) over three and an odor activity
value (OAV) over ten, were eventually obtained. Trimethylamine (fishy) was the only MKOC in all four parts. Besides,
benzaldehyde (almond-like) and (Z)-4-heptenal (fishy) were the MKOC in the abdomen meat and leg meat, respectively.
3 MKOCs were found in the gonad part, including hexanal (grassy), 1-octen-3-ol (mushroom) and nonanal (grassy).
Conclusion: Six MKOCs were verified to have relative high odor activities by both OAV and GC-O methods.
Those MKOCs might represent the key odor characteristics of different edible parts of male E. sinensis farmed in Chongming region.
However, the task of revealing formation mechanism for these MKOCs remains to be carried out in the future.
- Determination of the effects of different washing processes on aroma characteristics in silver carp mince by MMSE-GC-MS, e-nose and sensory evaluation
Xuxia Zhou, Yunqing Chong, Yuting Ding, Saiqi Gu, , Lin Liu. Food Chemistry, Volume 207:205-13. doi: 10.1016/j.foodchem.2016.03.026
<< Read Abstract >>
Keywords:
Silver carp; Washing; Monolithic material sorptive extraction (MMSE); Odor activity value (OAV); Gas chromatography-mass
spectrometry (GC-MS); E-nose; Sensory evaluation
Abstract:
The present study investigated the volatile compounds of silver carp mince and the effects of washing processes on
the integral aroma characteristics and aroma-active compounds (AACs) of the mince. 57 volatile compounds were identified
by monolithic material sorptive extraction (MMSE) and GC-MS analysis, and 13 volatile compounds with odor activity
values greater than 1 (OAVs > 1) were further selected as AACs contributing primarily to the integral aroma profile
of silver carp. Washing methods affected the overall aroma profiles of fish samples by washing away or facilitating
the release of AACs but to different extents. Compared with water washing, washing with saline and weak alkaline
solution removed more AACs. Washing with water three times (T2) exhibited a relatively stronger removal effect on
most AACs compared to washing with water twice (T1). Washing with a high concentration of saline (T4) produced a strong
removal effect on AACs. The results of sensory evaluation and electronic nose (e-nose) detection for distinguishing
the aroma characteristics of different samples demonstrated good agreement with those obtained by OAV analysis.
- Characterization of important odorants in four steamed Coilia ectenes from China by gas chromatography-mass spectrometry-olfactometry
Lin min Zhao,Wei Wu, Ning ping Tao, Yu qi, Na Wu, Xiao Qin. Fisheries Science 81(5) - July 2015, DOI: 10.1007/s12562-015-0907-2
<< Read Abstract >>
Abstract:
Odorants were extracted from four Coilia ectenes (Yangtze River-Coilia, East China sea-Coilia, Chao Lake-Coilia and
Yellow River-Coilia) by MonoTrap and analyzed by the headspace-monolithic material sorptive extraction technique
combined with gas chromatography-mass spectrometry-olfactometry (GC-MS-O). A total of 63 volatile compounds were
identified. The results of GC-MS-O analysis associated with odor intensity revealed that trimethylamine (fishy, ammonia-like),
1-penten-3-ol (mushroom, cabbage), N,N-diethyl-formamide (roasted meaty), hexanal (grassy, earthy), ethylbenzene
(nutty, floral), (Z)-4-heptenal (fishy, boiled potato), benzaldehyde (almond, metallic), 1-octen-3-ol (mushroom, cabbage),
nonanal (oily), and decanal (green, oily) were the important odorants in the four species of Coilia ectenes. Furthermore,
trimethylamine and 1-penten-3-ol were common to four Coilia ectenes. TMA (fishy, ammonia-like), 1-penten-3-ol (mushroom, cabbage),
N,N-diethyl-formamide (roasted meaty), hexanal (grassy, earthy), (Z)-4-heptenal (fishy, boiled potato), and benzaldehyde
(almond, metallic) were included in Yangtze River-Coilia; TMA, 1-penten-3-ol, ethylbenzene (nutty, floral), (Z)-4-heptenal,
1-octen-3-ol (mushroom, earthy), and nonanal (oily) in East China sea-Coilia; TMA, 1-penten-3-ol, ethylbenzene, 1-octen-3-ol
and nonanal in Chao Lake-Coilia; and TMA, 1-penten-3-ol, hexanal, (Z)-4-heptenal, 1-octen-3-ol and decanal (green, oily)
in Yellow River-Coilia.
- Optimization of Disk Sorptive Extraction Based on Monolithic Material for the Determination of Aroma Compounds from Lantana camara L. by
Gas Chromatography-Mass Spectrometry
Hye-Jin Jang, Hyun-Hwa Son, and Dong-Sun Lee. Bull. Korean Chem. Soc. 2011, Vol. 32, No. 12 4275
<< Read Abstract >>
Key Words : Lantana camara, Monoliths, Monolithic material sorptive extraction, Aroma, GC-MS
resent study describes the optimization of disk type sorptive extraction using monolithic material (Mono Trap)
for the analysis of volatile aroma compounds from Lantana camara L. in combination with gas chromato-
graphy/mass spectrometry (GC/MS). Monolithic material sorptive extraction (MMSE) is a new sampling
technique using a monolithic hybrid adsorptive disk (O.D. 10 mm, 1 mm thickness) made of high purity silica
and activated carbon having a large surface area chemically bonded with octadecyl silane (ODS). The
experimental parameters that may influence the MMSE efficiency have been optimized. Linearity, accuracy,
precision and detection limits were evaluated to assess the performance of the proposed method. The method
was validated with real plant samples of Lantana camara L. Twenty eight compounds including the main
representative compounds of a-curcumene and ß-caryophyllene were found in analyzed samples. Results
proved that proposed method could be used as a good alternative for the analysis for such volatile aroma
compounds in plant samples.
- Comparison of Volatile Flavor Components in Hepatopancreas and Gonads of Raw and Cooked Chinese Mitten Crab
GAO Xian-chu, GU Sai-qi, TAO Ning-ping, WANG Xi-chang, ZHUANG Jing, WU Na, LI Tai-hang. 2014, Vol.35, No.18 , doi:10.7506/spkx1002-6630-201418026
<< Read Abstract >>
Key Words: Eriocheir sinensis; monotrap; statistical significance analysis; relative odoractive value (ROAV)
Abstract:
The purpose of this work was to compare the characteristic volatile compounds in two edible parts (hepatopancreas
and gonads) of raw and cooked male Chinese mitten crab (Eriocheir sinensis) from Yangcheng Lake. The volatile compounds
were extracted with a novel adsorbant (MonoTrap) by solid-phase extraction and analyzed by gas chromatography-mass
spectrometry (GC-MS). Totally 90 volatile compounds were identified by GC-MS and compared for significant differences.
Except aromatic compounds, all seven other chemical groups of the volatile compounds presented significant differences
between the hepatopancreas and gonads, as well as between raw and cooked samples of either one. A large number of
aldehydes, furans and N-/S-containing compounds were produced during cooking. Among the 90 volatile compounds,
15 compounds were selected as the major volatile compounds with ROAV values of greater than 0.1, and 9 compounds
were selected as the prominent aroma-active compounds with ROAV values of greater than 1. In addition, decanal,
trimethylamine, nonanal and octanal made a significant contribution to the overall flavor of raw/cooked hepatopancreas and
gonads of Chinese mitten crab
- Sampling, identification and sensory evaluation of odors of a newborn baby’s head and amniotic fluid
Tatsuya Uebi, Takahiko Hariyama, Kazunao Suzuki, Naohiro Kanayama, Yoshifumi Nagata, Saho Ayabe-Kanamura, Shihoko Yanase, Yohsuke Ohtsubo,
Mamiko Ozaki Scientific Reports (2019) 9:12759, https://doi.org/10.1038/s41598-019-49137-6,
download
For baby odor analyses, noninvasive, stress-free sample collection is important. Using a simple
method, we succeeded in obtaining fresh odors from the head of five newborn babies. These odors
were chemically analyzed by two-dimensional gas chromatography coupled with mass spectrometry
(Gc x GC-MS), and compared with each other or with the odor of amniotic fluid from the baby’s
mother. We identified 31 chemical components of the volatile odors from neonate heads and 21 from
amniotic fluid. Although 15 of these components were common to both sources, there was an apparent
difference in the GC x GC patterns between the head and amniotic fluid odors, so the neonate head
odor might be individually distinct immediately after birth. Therefore, we made artificial mixtures of the
major odor components of the neonate head and maternal amniotic fluid, and used psychological tests
to examine whether or not these odors could be distinguished from each other. Our data show that the
artificial odor of a neonate head could be distinguished from that of amniotic fluid, and that the odors of
artificial head odor mixtures could be correctly discriminated for neonates within an hour after birth and
at 2 or 3 days of age.
- Detection of tobacco smoke emanating from human skin surface of smokers employing passive flux sampler - GCMS system
<< Read Abstract >>
Cigarette smoking is a significant risk factor for higher incidences of numerous adverse health consequences.
Related health disorders are also found in non-smokers exposed to secondhand smoke (SHS). To investigate the
influence of cigarette smoking and exposure to SHS on the composition of human skin gas, a trace biogas
emanating from human skin, dermal emissions of volatile compounds were semi-quantitatively measured for
volunteers who smoke a cigarette and those exposed to SHS. This was performed using a passive flux sampler
(PFS) coupled with gas chromatography mass spectrometry (GCMS). Numerous chemicals were detected, in-
cluding acetaldehyde, toluene, 3-methyl furan (3-MF), 2,5-dimethyl furan (2,5-DMF), 3-ethenyl pyridine (3-EP),
and nicotine, in the samples collected from the smokers after a smoking event, and a remarkable increase in the
amount of chemicals collected was observed just after smoking. These chemicals were also found in the samples
collected from volunteers exposed to SHS. Assessment of current smoking status is important for managing the
negative effects of active and passive smoking, and for the development of public health policy. The tobacco
specific chemicals such as 3-MF, 2,5-DMF, 3-EP, and nicotine, emanating from human skin surfaces, represent a
potential non-invasive biomarker for monitoring current smoking status of active and passive smokers after
establishing a more quantitative procedure.
- Determination of volatile organic compounds in the stinkhorn fungus Pseudocolus fusiformis in different stages of fruiting body formation.
Pattana Kakumyan, Nakarin Suwannarach, Jaturong Kumla, Natsaran Saichana, Saisamorn Lumyong, Kenji Matsui
Mycoscience ( IF 1.172 ) Pub Date : 2019-11-07
DOI: 10.1016/j.myc.2019.11.001
A stinkhorn fungus was collected from the mountainous area of Yoshida campus, Yamaguchi University, Japan. Morphological characterization and similarity of
large subunit ribosomal DNA sequences identified the fungus as Pseudocolus fusiformis. MonoTrap was combined with gas chromatography-mass spectrometry
(GC-MS) to identify volatile organic compounds (VOCs) emitted from the fungus harvested at different stages of maturity. The main VOCs emitted from
the mature fruiting body were 3-methyl-butanol, 4-methyl-phenol, and dimethyl tetrasulfide, while none of these compounds were detected in the egg-shaped state.
Volatile sulfur-containing compounds, including dimethyl disulfide, trisulfide and tetrasulfide, which are commonly detected in stinkhorn fungi and truffles,
were also emitted from this fungus. Furthermore, results elucidated that most VOCs occurred in the mature stage of Ps. fusiformis (fruiting body with arms fuse).
This is the first study reporting VOC production of Ps. fusiformis.
- Antifungal spectrum characterization and identification of strong volatile organic compounds produced by Bacillus pumilus TM-R
<< Read Abstract >>
To obtain biocontrol agents for suppression of food-deteriorating fungi during storage of agricultural products, bacteria producing volatile organic compounds (VOCs)
with strong antifungal activity were screened and isolated from various environmental samples. Among 136 bacterial isolates, strain TM-R showed the strongest and
broadest antifungal activity. Based on physiological and genetical characterization, the bacterium was identified as Bacillus pumilus. The effects of VOCs produced by the
bacterium, which was grown on four types of agar media (nutrient, Trypto-Soya, Luria-Bertani, and TM Enterprise), were examined against six species of fungi
(Alternaria alternata, Aspergillus niger, Cladosporium cladosporioides, Curvularia lunata, Fusarium oxysporum, and Penicillium italicum) in both small- and large-scale
tests (plate and 12-L tests, respectively). In the plate test, the bacterium markedly suppressed the mycelial growth of five fungi (Alternaria alternata, Cladosporium
cladosporioides, Curvularia lunata, F. oxysporum, and P. italicum) but promoted the growth of Aspergillus niger. In the 12-L test, the degree of growth inhibitiondecreased;
however, the bacterium grown on TMEA still exhibited the strongest inhibition, especially against P. italicum (growth inhibition rate of 93%).
Surprisingly, the growth of Aspergillus niger was promoted even more strongly (-36%) by the bacterium on TMEA than in the plate test (-9%).
Twenty-two of 32 VOCs detected by GC-MS were identified using three databases (NIST 2011, AromaOffice, and AroChemBase).
The species and concentration of detected VOCs differed greatly among growth media. To identify causative antifungal VOCs, we estimated the correlation between
growth inhibition of P. italicum by the bacterium grown on each of the four media vs. the relative abundance of individual VOCs. As a result, four VOCs
(methyl isobutyl ketone, ethanol, 5-methyl-2-heptanone, and S-(-)-2-methylbutylamine) were determined to be the predominant antifungal VOCs. To the best of our knowledge, this study is the first to specify causative antifungal VOCs using such an approach.
- Organic compositional analysis of propellant powders using monolithic material sorption extraction (MSSE)-a feasibility study
Ellen Goudsmits, George P Sharples and Jason W Birkett
J Forensic Sci Res. 2017; 1: 068-076 , doi.org/10.29328/journal.jfsr.1001009
<< Read Abstract >>
The application of monolithic material sorption extraction, specifi cally MonoTrap, to the extraction of
organic gunshot residue (OGSR) compounds from unburnt propellant powders is described. Four different
MonoTraps were assessed for their capability to extract OGSR compounds from two different ammunition
types. Extracts were analysed using gas chromatography-mass spectrometry. Results indicated that the carbon
disc was suitable for the extraction of OGSR compounds from unburnt propellant powders. Quantities for
major compounds were comparable to methanol extractions. The method was successfully used to detect a
wide range of OGSR compounds, including nitrotoluenes, nitroglycerin, diphenylamines and centralites and is
expected to be applicable to a wide range of ammunition types.
- Odor-Active Components of Luo Han Guo (Siraitia grosvenorii)
<< Read Abstract >>
The volatile components of the dried fruit of Luo Han Guo (Siraitia grosvenorii Swingle) belonging to the family Cucurbitaceae were analyzed by
AROMASCOPE technique using MonoTrap DCC18 as an absorbent. A total of 124 volatile components were identified from the headspace aroma solvent
extract. The major components were ethanol, butan-l-ol, pentanal, 2-methylbutanal, hexanal, furfural, pent-3-en-2-one, acetic acid, propionic acid, 3-
methylbutanoic acid, hexadecanoic acid, and so on. Among them, acetic acid, 3-methylbutanoic acid, and 3-hydroxy-4,5-dimethylfuran-2(5H)-one (sotolon)
strongly contributed to the overall aroma of the fruit. Besides, sotolon and 5-ethyl-3-hydroxy-4-methylfuran-2(5H)-one (maple furanone) were responsible for
the characteristic molasses-like aroma of the fruit.
- Analysis of volatile aroma compounds from vanilla perfume using headspace disk type monolithic material sorptive extraction
<< Read Abstract >>
In this study, headspace disk type monolithic material sorptive extraction (HS-MMSE) was developed,
validated and applied to the analysis of volatile aroma compounds from vanilla perfume by gas chromatography
-mass spectrometry (GC/MS). HS-MMSE uses monolithic material (MonoTrap) based on silica bonded with
octadecyl silane (ODS) and activated carbon as a sorbent. Aroma compounds was adsorbed onto the MonoTrap
in headspace and extracted by only 100 µL of solvent. Total 12 volatile compounds from vanilla perfume were
successfully analyzed using HS-MMSE. The influence of extractive parameters was investigated and optimized,
using benzyl acetate, linalyl acetate, vanillin, ethyl vanillin as target compounds. Under the optimum condition,
the limit of detection (S/N = 3) and the limit of quantification (S/N = 10) of proposed method for the target
compounds were obtained within the range of 8.35~13.76 ng and 27.82~45.88 ng, respectively. The method
showed good linearity with correlation coefficient more than 0.9888, satisfactory recovery and reproducibility.
- A herbivore-induced homoterpene volatile is emitted from Basella alba leaves
<< Read Abstract >>
An irregular C11 homoterpene, (E)-4,8-dimethylnona-1,3,7-triene (DMNT) was identified as a
major component of the volatile compounds emitted from Basella alba leaves induced by
herbivore. The terpenes including DMNT were not detected from the leaves infected by
Botrytis cinerea. These results suggested that volatile emission from B. alba leaves was
induced by herbivory but not by a fungal infection.
- Elucidation of Biochemical Pathways Underlying VOCs Production in A549 Cells
<< Read Abstract >>
Cellular volatile organic compounds (VOCs) are unique compounds whose metabolic pathways remain enigmatic. To elucidate their metabolism, we investigated the VOCs
of lung cancer A549 and 2 non-cancer lung cells (HLB; HBEpC). Neutral sugars and lactate in the medium were measured by colorimetric assay.
VOCs were enriched by monotrap and profiled by GC-MS. To investigate the enzymes that change VOC metabolism in cells, we conducted ALDH activity assays and qPCR.
ROS (reactive oxygen species) assays were conducted to assess oxidation stress. The colorimetric assay showed that especially A549 and HLB took up sugars from the
medium and rapidly secreted lactate into the medium. The VOC profile (GC-MS) revealed a trans-2-hexenol increase, especially in A549 lung cancer cells.
This is a novel lipid peroxidation product from animal cells. Based on the absolute quantification data, trans-2-hexenol increased in parallel with number of
A549 cancer cells incubated. The qPCR data implies that ADH1c potentially plays an important role in the conversion into trans-2-hexenol.