Volatile Profiling of Fifteen Willow Species and Hybrids and Their Responses to Giant Willow Aphid Infestation

The giant willow aphid (Tuberolachnus salignus) is a large stem-feeding insect which forms dense colonies on infested plants. Since T. salignus is a new invasive species in New Zealand, we have a poor understanding of the plant chemical responses to aphid infestation. This study aimed to characterize the volatile organic compounds (VOCs) emissions of fifteen different willow species and hybrids growing in New Zealand, and to evaluate changes in response to T. salignus attack in a field trial. Volatiles were collected using a headspace sampling technique and analysed using gas chromatography-mass spectrometry (GC-MS). We found high variability in the volatile profiles of different species and hybrids, with (Z)-3-hexenyl acetate and (E)-β-ocimene being the only common components to all blends. Taxonomically related plants showed an overlapping pattern of VOC emission, and there seemed to be a clear separation between shrub and tree willows. Responses to aphid infestation were variable, with only four species/hybrids showing changes in their total VOC emission, or that of at least one class of VOCs. A weak positive correlation between aphid population estimates and VOC emissions suggests that responses are species-specific and not infestation-dependent. These results reveal useful information about the interaction between T. salignus and its potential host plants for biological control and pest management purposes.

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Concentrations of Seven Phthalate Monoesters in Infants and Toddlers Quantified in Urine Extracted from Diapers

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18136806 ◽

2021 ◽

Vol 18 (13) ◽

pp. 6806

Author(s):

Fiorella Lucarini ◽

Marc Blanchard ◽

Tropoja Krasniqi ◽

Nicolas Duda ◽

Gaëlle Bailat Rosset ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Young Children ◽

Sampling Technique ◽

Gas Chromatography Mass Spectrometry ◽

Urine Collection ◽

Infants And Toddlers ◽

Urine Sampling ◽

Disposable Diapers ◽

Children’S Exposure

Carrying out exposure studies on children who are not toilet trained is challenging because of the difficulty of urine sampling. In this study, we optimized a protocol for urine collection from disposable diapers for the analysis of phthalate metabolites. The exposure of Swiss children (n = 113) between 6 months and 3 years of life to seven phthalates was assessed by gas chromatography–mass spectrometry measurements. The study showed limited exposures to phthalates, with only 22% of the samples containing some of the metabolites investigated. The three most frequently detected metabolites were monoethyl phthalate, mono-cyclohexyl phthalate, and mono-benzyl phthalate. We also detected mono-n-octyl phthalate and mono(3,5,5-trimethylhexyl) phthalate, which have rarely been observed in urine from infants and toddlers; therefore, di-n-octyl phthalate and bis(3,5,5-trimethylhexyl) phthalate can be considered as potentially new emerging phthalates. This study presents an initial snapshot of the Swiss children’s exposure to phthalates and provides a promising approach for further phthalate biomonitoring studies on young children using disposable diapers as urine sampling technique.

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Changes in Phenols, Polysaccharides and Volatile Profiles of Noni (Morinda citrifolia L.) Juice during Fermentation

Molecules ◽

10.3390/molecules26092604 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2604

Author(s):

Zhulin Wang ◽

Rong Dou ◽

Ruili Yang ◽

Kun Cai ◽

Congfa Li ◽

...

Keyword(s):

Octanoic Acid ◽

Solid Phase ◽

Principal Component ◽

Hexanoic Acid ◽

Morinda Citrifolia ◽

Gas Chromatography Mass Spectrometry ◽

Aroma Characteristics ◽

Volatile Profiles ◽

The Difference ◽

Aroma Components

The change in phenols, polysaccharides and volatile profiles of noni juice from laboratory- and factory-scale fermentation was analyzed during a 63-day fermentation process. The phenol and polysaccharide contents and aroma characteristics clearly changed according to fermentation scale and time conditions. The flavonoid content in noni juice gradually increased with fermentation. Seventy-three volatile compounds were identified by solid-phase microextraction coupled with gas chromatography–mass spectrometry (SPME-GC-MS). Methyl hexanoate, 3-methyl-3-buten-1-ol, octanoic acid, hexanoic acid and 2-heptanone were found to be the main aroma components of fresh and fermented noni juice. A decrease in octanoic acid and hexanoic acid contents resulted in the less pungent aroma in noni juice from factory-scale fermentation. The results of principal component analysis of the electronic nose suggested that the difference in nitrogen oxide, alkanes, alcohols, and aromatic and sulfur compounds, contributed to the discrimination of noni juice from different fermentation times and scales.

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Differences in New Zealand Hop Cultivars Based on Their Unique Volatile Compounds: An Integrated Fingerprinting and Chemometrics Approach

Foods ◽

10.3390/foods10020414 ◽

2021 ◽

Vol 10 (2) ◽

pp. 414

Author(s):

Victoria Purdy ◽

Biniam Kebede ◽

Ron Beatson ◽

Kerry Templeton ◽

Patrick Silcock ◽

...

Keyword(s):

New Zealand ◽

Volatile Compounds ◽

Gas Chromatography Mass Spectrometry ◽

Headspace Gas Chromatography ◽

Commercial Cultivars ◽

Headspace Gas ◽

Chemical Fingerprinting ◽

Chemical Profiles ◽

Aroma Characteristics ◽

Feature Selection Techniques

Hop aroma characteristics originate from hop essential oils, which have complex chemical profiles that remain poorly understood, particularly for New Zealand hops. The aim of this study was to determine volatile compounds that distinguish New Zealand hop cultivars. Untargeted fingerprinting methods based on headspace gas chromatography mass spectrometry (GC-MS) were used to analyse nine hop cultivars. A total of 61 volatile compounds were identified as compounds that differentiated the commercial hop varieties using advanced chemometrics and feature selection techniques. Similarities in volatile composition were found between Wakatu, Wai-iti™ and Kohatu®, which are rich in alcohols. Another grouping was found between Waimea™ and Nelson Sauvin™, where ketones and esters were commonly found. Rakau™ was distinct from the other eight cultivars, distinguished by 2-methylbutyl 3-methylbutanoate and methanethiol hexanoate. Riwaka™ contained the greatest number of discriminating volatile compounds when compared to other cultivars, which was dominated by terpenoids, such as geranyl 2-methylbutanoate, perillene and D-limonene. The chemical fingerprinting approach successfully identified volatile compounds that had not been previously found in New Zealand hop cultivars and that discriminated the commercial cultivars. The data obtained in the present study further extend the knowledge of New Zealand hops and will help facilitate targeted breeding.

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Headspace solid-phase microextraction (HS-SPME): a microscale sampling technique for determination of monoterpene hydrocarbons in coniferous needles by gas chromatography/mass spectrometry (GC/MS)

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-003-2271-9 ◽

2004 ◽

Vol 378 (1) ◽

pp. 150-158 ◽

Cited By ~ 9

Author(s):

I. Chv�l�ckov� ◽

V. Kub�n

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Solid Phase Microextraction ◽

Solid Phase ◽

Sampling Technique ◽

Gas Chromatography Mass Spectrometry ◽

Headspace Solid Phase Microextraction ◽

Monoterpene Hydrocarbons ◽

Coniferous Needles

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Hydrogen sulphide inhibits PSII of lichen photobionts

The Lichenologist ◽

10.1017/s0024282912000667 ◽

2013 ◽

Vol 45 (1) ◽

pp. 101-113 ◽

Cited By ~ 10

Author(s):

Stefano BERTUZZI ◽

Mauro TRETIACH

Keyword(s):

Hydrogen Sulphide ◽

Vascular Plants ◽

Solid Phase ◽

Photosynthetic Apparatus ◽

Sample Surface ◽

Gas Chromatography Mass Spectrometry ◽

Solid Phase Micro Extraction ◽

Action Mechanisms ◽

Species Specific ◽

Closed Chambers

AbstractThe effects of hydrogen sulphide (H2S) on five lichens with different photobionts, ecology, and tolerance to the pollutant were studied by means of samples exposed in closed chambers containing two known H2S solutions. The H2S concentration in the void volume at equilibrium with the liquid phase was measured by gas chromatography-mass spectrometry, combined with the use of solid phase micro extraction (GC/MS SPME). It was determined as 8 and 28 ppm H2S in the absence of lichen material, andc. 2 and 10 ppm H2S respectively with living lichen material inserted for 8 hours in the exposure chambers. Significant differences in the species-specific emission of chlorophyllafluorescence (ChlaF) were observed, with a pronounced depression ofFv/Fmalready detectable after 2 h exposure at 28 ppm H2S in all the species. The decreased intensity was positively correlated to sample surface and, to a lesser extent, to the species-specific pre-exposureFv/Fmvalue. Dark-exposed samples were less affected than light-exposed ones. All four chlorolichens could recover the pre-exposure ChlaF emission after two days in the absence of H2S, both in the light and in the dark, whereas the cyanolichen did not recover when kept in the dark. The results are thoroughly discussed on the basis of the known action mechanisms of H2S on the photosynthetic apparatus of vascular plants and cyanobacteria.

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Economic Contributions and Challenges of Immigrant Entrepreneurs to Their Host Country – Case of African Immigrants in Auckland, New Zealand

Journal of Business Administration Research ◽

10.5430/jbar.v6n1p25 ◽

2017 ◽

Vol 6 (1) ◽

pp. 25

Author(s):

Olufemi Muibi Omisakin

Keyword(s):

New Zealand ◽

Small Business ◽

Host Country ◽

Sampling Technique ◽

Business Owners ◽

Small Business Owners ◽

Structured Interviews ◽

Immigrant Entrepreneurship ◽

Immigrant Entrepreneurs ◽

Definition Of

Entrepreneurship is an important concept in both developing and developed societies today. Although there is no consensus on the definition of entrepreneurship, it is believed to be a process of creating value by bringing together a unique package of resources to exploit entrepreneurship opportunities (Morris, 2002). This study aims to discover the economic contributions and challenges of immigrant entrepreneurs to their host country, and focuses on African small business owners in Auckland, New Zealand. Literature on immigrant entrepreneurship was reviewed, resulting in a discussion of the economic contributions of immigrant entrepreneurship as well as its challenges. Data was collected using face-to-face, semi-structured interviews, observation and field notes as the sources of inquiry. A purposive sampling technique was used to select 17 participants. All participants were African immigrant small business owners running businesses in Auckland. Thematic analysis was used to analyse the data collected (Braun & Clarke, 2006).

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Waste to Carbon: Influence of Structural Modification on VOC Emission Kinetics from Stored Carbonized Refuse-Derived Fuel

Sustainability ◽

10.3390/su11030935 ◽

2019 ◽

Vol 11 (3) ◽

pp. 935 ◽

Cited By ~ 7

Author(s):

Andrzej Białowiec ◽

Monika Micuda ◽

Antoni Szumny ◽

Jacek Łyczko ◽

Jacek Koziel

Keyword(s):

Structural Modification ◽

Solid Phase ◽

Gas Chromatography Mass Spectrometry ◽

Order Kinetic ◽

Voc Emissions ◽

Voc Emission ◽

First Order ◽

Refuse Derived Fuel ◽

Volatile Organic ◽

Order Kinetic Model

The torrefaction of municipal solid waste is one of the solutions related to the Waste to Carbon concept, where high-quality fuel—carbonized refuse-derived fuel (CRDF)—is produced. An identified potential problem is the emission of volatile organic compounds (VOCs) during CRDF storage. Kinetic emission parameters have not yet been determined. It was also shown that CRDF can be pelletized for energy densification and reduced volume during storage and transportation. Thus, our working hypothesis was that structural modification (via pelletization) might mitigate VOC emissions and influence emission kinetics during CRDF storage. Two scenarios of CRDF structural modification on VOC emission kinetics were tested, (i) pelletization and (ii) pelletization with 10% binder addition and compared to ground (loose) CRDF (control). VOC emissions from simulated sealed CRDF storage were measured with headspace solid-phase microextraction and gas chromatography–mass spectrometry. It was found that total VOC emissions from stored CRDF follow the first-order kinetic model for both ground and pelletized material, while individual VOC emissions may deviate from this model. Pelletization significantly decreased (63%~86%) the maximum total VOC emission potential from stored CDRF. Research on improved sustainable CRDF storage is warranted. This could involve VOC emission mechanisms and environmental-risk management.

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Odor fingerprinting of Listeria monocytogenes recognized by SPME–GC–MS and E-nose

Canadian Journal of Microbiology ◽

10.1139/cjm-2014-0652 ◽

2015 ◽

Vol 61 (5) ◽

pp. 367-372 ◽

Cited By ~ 16

Author(s):

Yong-xin Yu ◽

Xiao-hong Sun ◽

Yuan Liu ◽

Ying-jie Pan ◽

Yong Zhao

Keyword(s):

Listeria Monocytogenes ◽

Solid Phase ◽

Gas Chromatography Mass Spectrometry ◽

Growth Stages ◽

Relative Peak Area ◽

Volatile Organic ◽

Microbial Volatile Organic Compounds ◽

Odor Compounds ◽

Species Specific ◽

Different Growth Stages

Microorganisms can produce species-specific microbial volatile organic compounds (MVOCs), or odor compounds, which can be characterized by odor fingerprinting. The objective of this study was to characterize the odor fingerprint of Listeria monocytogenes. Solid-phase microextraction – gas chromatography – mass spectrometry (SPME–GC–MS) and electronic nose (E-nose) were used to recognize the MVOCs of L. monocytogenes in pure culture medium. The main MVOCs of L. monocytogenes were identified by SPME–GC–MS analysis as alcohols, aldehydes, ketones, alkanes, and heterocyclics, among which the relative peak area of one compound, 3-hydroxy-2-butanone, increased along with the growth of L. monocytogenes. The odor fingerprint of L. monocytogenes at different growth stages could be clearly discriminated by E-nose. In addition, E-nose signals had a very good linear relationship with the concentration of this bacterium (R2 = 0.9937). Our study may help to establish the analysis of the odor fingerprint of microorganisms as a potential routine method in microbiology.

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