Detection of mycobacteria by volatile organic compound analysis of in vitro cultures using differential ion mobility spectrometry

AbstractRapid, high-throughput diagnostic tests are essential to decelerate the spread of the novel coronavirus disease 2019 (COVID-19) pandemic. While RT-PCR tests performed in centralized laboratories remain the gold standard, rapid point-of-care antigen tests might provide faster results. However, they are associated with markedly reduced sensitivity. Bedside breath gas analysis of volatile organic compounds detected by ion mobility spectrometry (IMS) may enable a quick and sensitive point-of-care testing alternative. In this proof-of-concept study, we investigated whether gas analysis by IMS can discriminate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from other respiratory viruses in an experimental set-up. Repeated gas analyses of air samples collected from the headspace of virus-infected in vitro cultures were performed for 5 days. A three-step decision tree using the intensities of four spectrometry peaks correlating to unidentified volatile organic compounds allowed the correct classification of SARS-CoV-2, human coronavirus-NL63, and influenza A virus H1N1 without misassignment when the calculation was performed with data 3 days post infection. The forward selection assignment model allowed the identification of SARS-CoV-2 with high sensitivity and specificity, with only one of 231 measurements (0.43%) being misclassified. Thus, volatile organic compound analysis by IMS allows highly accurate differentiation of SARS-CoV-2 from other respiratory viruses in an experimental set-up, supporting further research and evaluation in clinical studies.

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Antagonisme beberapa bakteri endofit Arecaceae terhadap Curvularia sp. patogen penyebab bercak daun yang diisolasi dari tanaman kelapa kopyor (Antagonism of selected Arecaceae endophytic bacteria against Curvularia sp. leaf spot pathogen isolated from coconut kopyor)

E-Journal Menara Perkebunan ◽

10.22302/iribb.jur.mp.v86i2.318 ◽

2018 ◽

Vol 86 (2) ◽

Author(s):

Deden Dewantara ERIS ◽

Agus PURWANTARA ◽

Abdul MUNIF ◽

Bonny Poernomo Wahyu SOEKARNO

Keyword(s):

Organic Compound ◽

Volatile Organic Compound ◽

Leaf Spot ◽

Endophytic Bacteria ◽

Control Technique ◽

Leaf Spot Disease ◽

Inhibitory Ability ◽

Volatile Organic ◽

Keywords Antibiotics

Coconut kopyor is one of the most important commodities. One of the problems in coconut kopyor cultivation is grey leaf spot disease caused by Curvularia sp. Using endophytic bacteria is one of the control technique that is environmentally friendly. A total of 40 selected endophytic Arecaceaebacteria isolated from coconut kopyor, palm oil, aren, nibung and pejibaye were tested for their inhibitory ability to Curvularia sp.through antibiotic and volatile organic compound (VOC)test.The antibiotic test showed that thirty three endophytic bacteria isolates have inhibitory capacity againstCurvularia sp. in a range of inhibition from 4.4% to 86.6%. Isolates with the highest inhibition were EAKSS 502, EAKSS 520 and EAKSS 507. VOC test showed that EAPJN 216, EAKSS 532, EAAPN 225, EAAPN 506, EAAPN 507 and EAAPN 557 were produced VOC that suppressed the growth of Curvulariasp fungal colonies in a range from 92.27% to 97.21%. Based on the best combination of antibiotic and production of volatile organic compound test, there were four potential isolates to inhibit the growth of Curvulariasp. in vitro i.e. EAKSS 502, EAKSS 507, EAKPN 201 and EAPJN 216. Those isolates were molecularly identified as Serratia marcescensstrain PIGB81, Burkholderiasp. DOP Ma316, S. marcescensstrain RY21 and S. marcescensstrain LB21.The four isolates were isolated from different plants such oil palm, coconut kopyor and pejibaye.[Keywords: antibiotics,Burkholderia,malforma-tion, Serratia,suppression, volatile compound]AbstrakKelapa kopyor saat ini menjadi salah satu komoditas perkebunan yang penting. Salah satu masalah dalam pembudidayaan kelapa kopyor adalah serangan penyakit bercak kelabu yang disebabkan oleh cendawan Curvulariasp. Penggunaan bakteri endofit merupakan salah satu cara control yang ramah lingkungan.Sebanyak 40 isolat bakteri endofit asal tanaman Arecaceaediisolasi dari tanaman kelapa kopyor, kelapa sawit, aren, nibung dan pejibaye diujikan kemampuan penghambatannya terhadap Curvulariasp. melalui uji antibiosis dan uji produksi senyawa organik volatil (VOC). Uji antibiosis menunjukkan se-banyak 33 isolat bakteri endofit menunjukkan daya penghambatan terhadap cendawan Curvulariasp. dengan kisaran 4,4%-86,6%. Penghambatan terbesar yakni isolat EAKSS 502, EAKSS 520 dan isolat EAKSS 507. Pengujian produksi senyawa organik volatil menunjukkan EAPJN 216, EAKSS 532, EAAPN 225, EAAPN 506, EAAPN 507 dan EAAPN 557 menghasilkan komponen volatil organik yang menekan pertumbuhan koloni cendawan Curvulariasp. pada kisaran 92,27%- 97,21%. Berdasarkan kombinasi data pengujian antibioisis dan produksi senyawa organik volatilterdapat 4 isolat bakteri endofit yang berpotensi menghambat perkembangan Curvulariasp. yaitu isolat EAKSS 502, EAKSS 507, EAKPN 201 dan EAPJN 216.Hasil identifikasi secara molekuler ke empat isolat tersebut berturut-turut adalah Serratia marcescens strain PIGB81,Burkholderia sp. DOP Ma316,S. marcescens strain RY21danS. marcescens strain LB21. Keempat isolat tersebut diisolasi daritanaman yang berbeda yakni kelapa sawit, kelapa kopyor dan pejibaye.[Kata kunci: antibiotik, Burkholderia,malformasi, penghambatan, Serratia,komponen volatil].

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Photon flux density and wavelength influence on growth, photosynthetic pigments and volatile organic compound accumulation in Aeollanthus suaveolens (Catinga-de-mulata) under in vitro conditions

Industrial Crops and Products ◽

10.1016/j.indcrop.2021.113597 ◽

2021 ◽

Vol 168 ◽

pp. 113597

Author(s):

Diene Xavier Araújo ◽

Tainá Teixeira Rocha ◽

Alexandre Alves de Carvalho ◽

Suzan Kelly Vilela Bertolucci ◽

Ana Paula Ribeiro Medeiros ◽

...

Keyword(s):

Organic Compound ◽

Flux Density ◽

Volatile Organic Compound ◽

Photosynthetic Pigments ◽

Photon Flux ◽

Photon Flux Density ◽

Volatile Organic

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Detection and Identification of VOCs Using Differential Ion Mobility Spectrometry (DMS)

Molecules ◽

10.3390/molecules27010234 ◽

2021 ◽

Vol 27 (1) ◽

pp. 234

Author(s):

Wojciech Fabianowski ◽

Mirosław Maziejuk ◽

Monika Szyposzyńska ◽

Monika Wiśnik-Sawka

Keyword(s):

Organic Compounds ◽

Ion Mobility Spectrometry ◽

Ion Mobility ◽

Electric Field Intensity ◽

Ion Temperature ◽

Acetate Esters ◽

Differential Ion Mobility Spectrometry ◽

Detection And Identification ◽

Volatile Organic ◽

First Time

The article presents a technique of differential ion mobility spectrometry (DMS) applicable to the detection and identification of volatile organic compounds (VOCs) from such categories as n-alkanes, alcohols, acetate esters, ketones, botulinum toxin, BTX, and fluoro- and chloro-organic compounds. A possibility of mixture identification using only the DMS spectrometer is analyzed, and several examples are published for the first time. An analysis of different compounds and their mechanisms of fragmentation, influence on effective ion temperature, and high electric field intensity is discussed.

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