Structural characterization of major soyasaponins in traditional cultivars of Fagioli di Sarconi beans investigated by high resolution tandem mass spectrometry

Major soyasaponins, i.e., soyasaponins I, V, βg, and αg from traditional Fagioli di Sarconi beans (Phaseolus vulgaris L., ecotype Tabacchino), were analyzed by reversed-phase liquid chromatography–mass spectrometry (MS) using high-resolution Fourier transform ion cyclotron resonance (FTICR) MS on electrospray ionization in positive-ion mode. Fagioli di Sarconi beans are protected by the European Union [Commission Regulation (EC) No 1263/96] with the mark PGI (for “Protected Geographical Indication”), and are cultivated in Basilicata (southern Italy). Protonated adducts of soyasaponins I, V, βg, and αg were observed at m/z 943.5262, 959.5213, 1069.5583, and 1085.5534, respectively. Gas-phase dissociation of soyasaponins by infrared multiphoton dissociation FTICR MS was performed using a CO2 laser source at a wavelength of 10.6 μm. Most of the fragment ions were identified unambiguously by using the high-resolution and accurate mass value provided by the FTICR mass spectrometer. All soyasaponins exhibit a sequential and neutral loss of sugar moieties at relatively short irradiation times (i.e., less than 50 ms). When the pulse length was increased, a more pronounced fragmentation occurred, with several signals in the lower part of the mass spectrum. In the case of soyasaponins βg and αg, the occurrence of the conjugated product ion at m/z 127.0389 ([C6H6O3 + H]+, 2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one) was evidenced. Coupling reversed-phase liquid chromatography with high-performance FTICR MS in combination with infrared multiphoton dissociation tandem MS proved to be very promising for the structural characterization of soyasaponins, and is also suitable for the rapid and accurate structural investigation of other saponins

Biodegradation of carbamazepine and clarithromycin by Trichoderma harzianum and Pleurotus ostreatus investigated by liquid chromatography - high-resolution tandem mass spectrometry (FTICR MS-IRMPD)

In this study, the capability of pharmaceutical biodegradation of fungus Trichoderma harzianum was evaluated through the comparison with the well-known biodegradation capability of white-rot fungus Pleurotus ostreatus. The study was performed in aqueous phase under aerobic conditions, using two of the most frequently detected drugs in water bodies: carbamazepine and clarithromycin, with concentrations commonly found in treated wastewater (4 μg/l and 0.03 μg/l respectively). For the first time, we demonstrated that T. harzianum is able to remove carbamazepine and clarithromycin. The analyses were performed by reversed-phase liquid chromatography/mass spectrometry, using high-resolution Fourier-transform ion cyclotron resonance mass spectrometry upon electrospray ionization in positive ion mode. The high selectivity and mass accuracy provided by high-resolution mass spectrometry, allowed us to identify some unknown metabolites. On the basis of our study, the major metabolites detected in liquid culture treated by T. harzianum were: 14-hydroxy-descladinosyl- and descladinosyl-clarithromycin, which are pharmacologically inactive products not dangerous for the environment

Molecular formula analysis of fragment ions by isotope-selective collision-induced dissociation tandem mass spectrometry of pharmacologically active compounds

The purpose of this work is to explore the mass fragment characterization of commonly used drugs through a novel approach, which involves isotope-selective tandem mass spectrometry (MS/MS). Collision-induced dissociation (CID) was performed with a low-resolution linear ion trap mass spectrometer in positive electrospray ionization. Three pharmacologically active ingredients, i.e. omeprazole, meloxicam and brinzolamide, selected as model compounds in their own formulation, were investigated as a sodiated adduct [C17H19N3O3S+Na]+ (omeprazole) and as protonated adducts, [C14H13N3O4S2+H]+ and [C12H21N3O5S3+H]+, meloxicam and brinzolamide, respectively. Selecting a narrow window of ±0.5 m/z units, precursor ion fragmentation by CID-MS/MS of isotopologues A+ 0, A + 1 and A+ 2 was found very useful to confirm the chemical formula of product ions, thus aiding the establishment of characteristic fragmentation pathways of all three examined compounds. The correctness of putative molecular formula of product ions was easily demonstrated by exploiting the isotope peak abundance ratios (i.e. IF+0/IF+1 and IF+0/IF+2) as simple constraints in low-resolution MS instrumentations

Ancient pottery from archaeological sites in southern Italy: First evidence of red grape product markers

The chemical analysis of tartaric acid (TA) and syringic acid (SA), as grape product markers in ancient ceramic vessels from the sites of Manduria and Torre di Satriano (southern Italy), was successfully performed. Firstly, the fragmentation behaviour of TA and SA as deprotonated molecules, [M-H]-, obtained by collision-induced dissociation, was investigated. Then, reversed-phase liquid chromatog-raphy (RPLC) with electrospray ionization (ESI) in negative ion mode, using a quadrupole linear ion trap in multiple reaction monitoring (MRM), was employed. A binary mobile phase composed of water-acetonitrile with 0.1% (v/v) acetic acid enabled the optimum ESI effciency of SA, greatly improving its identifcation when it occurs in trace amounts. Chemical analysis of ancient pottery fragments is a valid method for establishing the existence of preserved organic residues, which is valuable new evidence for the culture and customs of ancient populations, in this case those of southern Italy. The proposed RPLC-ESI-MRM method allowed a systematic investigation of ceramic fragments of both archaeological sites, thus providing positive evidence for the presence of TA and SA as grape product markers in storage vessels dating back to the ninth to third centuries BC

Validation of an analytical method for simultaneous high-precision measurements of greenhouse gas emissions from wastewater treatment plants using a gas chromatography-barrier discharge detector system

Wastewater treatment plants (WWTPs) emit CO2 and N2O, which may lead to climate change and global warming. Over the last few years, awareness of greenhouse gas (GHG) emissions from WWTPs has increased. Moreover, the development of valid, reliable, and high-throughput analytical methods for simultaneous gas analysis is an essential requirement for environmental applications. In the present study, an analytical method based on a gas chromatograph (GC) equipped with a barrier ionization discharge (BID) detector was developed for the first time. This new method simultaneously analyses CO2 and N2O and has a precision, measured in terms of relative standard of variation RSD%, equal to or less than 6.6% and 5.1%, respectively. The method’s detection limits are 5.3 ppmv for CO2 and 62.0 ppbv for N2O. The method’s selectivity, linearity, accuracy, repeatability, intermediate precision, limit of detection and limit of quantification were good at trace concentration levels. After validation, the method was applied to a real case of N2O and CO2 emissions from a WWTP, confirming its suitability as a standard procedure for simultaneous GHG analysis in environmental samples containing CO2 levels less than 12,000 mg/L

N2O and CO2 Emissions from Secondary Settlers in WWTPs: Experimental Results on Full and Pilot Scale Plants

Data about Greenhouse Gas (GHG) emissions from settling units in wastewater treatment plants (WWTPs) are limited, probably because of the increased difficulties in evaluating direct emissions when there is absence of an induced air stream through the liquid volume (Caivano et al. 2016). Particularly, gas samples collection is not immediate and easy due to the low off-gas flow leaving the liquid surface. In this study, a modified off-gas apparatus is proposed, to avoid these experimental problems. A floating hood was connected to a blower to simulate the wind action and encourage the gas stripping. The incoming air flow rates were fixed to 4, 9, and 16 Nl min−1, simulating a wind velocity of 1.05, 2.36, and 4.19 m/s, respectively, in order to measure GHG emissions from a full-scale plant in several conditions. The same experimental conditions and a reproducible sampling apparatus were employed to measure GHG emissions also from a pilot plant. The monitoring of the full-scale plant shows that the concentrations of N2O and CO2 in the off-gas change rapidly, demonstrating the stripping effect induced by the blower air flow. A peak is reached and then a rapidly decrease is observed, proving a gradual decrease of mass transfer phenomena. As expected, the peak value increases with increasing the wind speed, whereas the time at which the peak is observed decreases. Regarding the pilot-scale plant, the results show the slow diffusion phenomena occurring in a closed system, preventing the mass transfer from the liquid to the gaseous phase

Lab-scale investigation on remediation of sediments contaminated with hydrocarbons by using super-expanded graphite

In view of necessity to develop simple, rapid, and efficient methods for monitoring and removal contaminants from soil, a new graphene-based material is presented for treatment of hydrocarbon-contaminated soils. Lab-scale experiments on three soil matrices featured by increasing granulometry were carried to evaluate graphene adsorption capability, as removal efficiency. Soil samples, firstly contaminated with different quantities of mineral exhausted oil up to final concentrations of 12500, 25000, 50000 mgkg-1, respectively, were treated with opportune amount of graphene. Results show as the removal efficiency of graphene is directly proportional to contamination level of the soil. Particularly, the best removal efficiency (87.04%) was reached during treatment of gravel samples at maximum contamination level using the highest dosage of graphene, even though good results (80.83%) were also achieved using lower graphene/pollutant ratio. Moreover, graphene at ratio 1/10 showed worse removal efficiencies in treating sea (81.17%) and silica sand (63.52%) than gravel. In this study, also the thermal regeneration was investigated in order to evaluate a possible reuse of graphene with subsequent technical and economic advantages. Graphenetechnique proves to be technologically and economically competitive with other currently used technologies, revealing the best choice for the remediation of hydrocarbon-contaminated soils