TABLE 1.
Investigated Bacillus subtilis isolates.
| Bacillus subtilis isolate | Habitate | Medium used for VOC-collection | Collection | Analysis | Identification | References |
| B. subtilis ATCC 6051 | Unknown (Zeigler et al., 2008) | Tryptic soy broth (TSB) | Static system – culture shaked at 30°C | SPME – PDMS at day 5 of cultivation | Medium comparison – Wiley 138K Mass Spectral Database, authentic standards for most chemicals | Robacker et al. (1998) |
| B. subtilis 168 | Mutant of the Bacillus subtilis type strain Marburg (Burkholder and Giles, 1947) | Murashige–Skoog (MS) medium containing 1.5% (w/v) agar, 1.5% (w/v) Suc, and 0.4% (w/v) TSA | Dynamic open air stream system – Plates in a Teflon framed chamber at 28°C | Trapping – Super-Q adsorbent traps at 48 h of cultivation – intervals of 24 h over 6 days | Medium comparison – EPA/NIST library, authentic standards | Ryu et al. (2004) |
| Lysogeny broth (LB) | Static system – 7 ml in culture a 20 ml vial at 37°C | SPME – DVB/CAR/PDMS at 24 h of cultivation | Medium comparison – NIST/EPA/NIH Mass Spectral Database (NIST 05) | Li et al. (2015) | ||
| B. subtilis 7, 8 and 9 | Tobacco fields | Beef extract peptone broth (BEPB) | Static system – 9 ml in a 15 ml vial at 37°C | SPME – coating not defined at 24 h of cultivation | medium comparison – Wiley 138 and NBS 75 k library (similarity index > 850) | Gu et al. (2007) |
| B. subtilis B2g | Rhizosphere of Brassica napus (Berg et al., 2002) | Nutrient agar (NA) | Dynamic open air stream system – plates in a glass chamber at 30°C | Trapping – Super-Q adsorbent traps at 48 h of cultivation for 24 h | Medium comparison – no compound detected | Kai et al. (2007) |
| B. subtilis JA | Soil | LB | Dynamic open air stream system – 100 ml culture in 250 ml flasks | Trapping – charcoal adsorbent traps | Medium comparison – NIST/EPA/NIH Mass Spectral Library (Software Version 2.0) | Chen et al. (2008) |
| B. subtilis G8 | From soil in greenhouse (China) | TSB-yeast extract (TSB-YE) | Static system – 25 ml culture in a 50 ml vial at 30°C | SPME – CAR/DVB/PDMS, PDMS and PDMS/DVB after reaching an OD600 of 1.0–1.5 | Medium comparison – NIST 05 library | Liu et al. (2008a) |
| B. subtilis BL02 | Rhizosphere soil of cucumber | LB | At 30°C | Method not mentioned – after 24 h | NIST 05 library | Liu et al. (2008b) |
| B. subtilis PPCB001 | Surface of Valencia and Shamouti oranges (Obagwu and Korsten, 2003) | NA | Dynamic system (Purge and Trap system) – 150 ml culture | Trapping – multi-channel open tubular silicone rubber traps (MCTs) | Wiley spectral library (>80% similarity), calculation and comparison of retention times (not clear whether authentic standards have been used) | Arrebola et al. (2010) |
| B. subtilis G-1 | Not defined | NA | Culture supernatant was extracted and separated using TLC | Direct GC-injection of one TLC fraction | NIST Version. 2.0 (2005) | Shifa et al. (2015) |
| B. subtilis SV75-1, SV44-2, SV36-2 | From different cooked food sources (meat and vegetables) | Plate count agar (PCA, Oxoid) | Static system – 5 ml of PCA in a 20 ml vial at 28°C | SPME – CAR/PDMS at day 5 of cultivation | Medium comparison – NIST 98/Wiley ver. 6 Mass Spectral Database (probability set at >90%). Std. when possible | Chaves-López et al. (2015) |
| B. subtilis 8B-1 | Potato field | LB | Static system – 100 ml in a 200 ml Erlenmeyer at 24°C | SPME – PDMS/DVB at day 5 of cultivation | NIST MS database Version 2.0 (<850) | Khabbaz et al. (2015) |
| B. subtilis XF-1 | Rhizosphere soil of Chinese cabbage (Brassica pekinensis) (Guo et al., 2013) | LB | Static system – 7 ml in a 20 ml vial at 37°C | SPME – DVB/CAR/PDMS at 24 h of cultivation | Medium comparison – NIST/EPA/NIH Mass Spectral Database (NIST 05) | Li et al. (2015) |
| B. subtilis M29 | From vermicompost | LB | Static system – cultivation in a 500 ml vial at 30°C | SPME – CAR/PDMS | NIST/MAINLIB/WileyRegistry/Rtlpest library – authentic standards whenever possible | Mu et al. (2017) |
| B. subtilis SYST2 | Not-defined | MS | Static system – 30 ml of MS agar medium in a 100 ml vial at 28°C | SPME – DVB/CAR/PDMS at day 5 of cultivation | Medium comparison – NIST/EPA/NIH Mass Spectrum Library – Std. (albuterol) | Tahir et al. (2017) |
| B. subtilis FA26 | Rhizosphere of rice grown in Pakistan | LB | Static system – 30 ml of MS agar medium in a 100 ml vial at 28°C | SPME – DVB/CAR/PDMS at day 3 of cultivation | Medium subtraction – NIST 11 Mass Spectrum Library (NIST11/2011/EPA/NIH) in NIST MS Search software version 2.0g (2011–05) | Rajer et al. (2017) |
| B. subtilis NCTC 10073 | Not defined | Agar medium | Dynamic closed air stream system – 5 ml of MS agar medium in a 30 ml vial at 30°C | TenaxTM-Carbograph desorption tube – monitoring for 3 days (intervals of 24 h at 24 h, 48 h and 72 h of cultivation) | Medium subtraction – NIST MS database, version 2.0 | Ratiu et al. (2017a) |
| B. subtilis CF-3 | Fermented bean curd, China (Gao et al., 2016) | LB | Static system – 100 ml of MS medium in a 100 ml vial at 28°C | SPME – PA 100-μm PDMS, 7-μm PDMS from 12 h to 96 h every 12 h | Medium comparison – National Institute for Standards and Technology (NIST, 2008) Mass Spectrometry Library | Gao et al. (2018) |
| B. subtilis | Pig (Sus scrofa domesticus) decomposition studies | NA | Static system – 4 ml of medium in a 20 ml vial at 24°C | SPME – CWR/PDMS Arrows (in-house production) every 24 h over a 5-day period | Medium comparison – National Institute of Standards and Technology (NIST) 2014 Mass Spectral Library with a forward match factor threshold of 700 and reverse match factor threshold of 700 | Eckert et al. (2018) |
| B. subtilis (MTCC 8133, 8114, and 2274) | Not defined | NA | Static system – NA plate at 28 ± 2°C | SPME – CAR/DVB at day 4 of cultivation | WILEY and NIST Library | Jangir et al. (2018) |
EPA, Environmental Protection Agency; NIH, National Institute of Health database; NIST, National Institute of Standards and Technology; TLC, thin-layer chromatography; DVB, divinylbenzene; PDMS, polydimethylsiloxane; CAR, carboxen; PA, polyacrylate; CWR, carbon wide range.