The effect of different hydrodistillation pretreatments, namely, reflux extraction, reflux extraction with the addition of cell wall-degrading enzymes, and ultrasound, on the yield and chemical ...composition of essential oils of sage, bay laurel, and rosemary was examined. All pretreatments improved essential oil yield compared to no-pretreatment control (40–64% yield increase), while the oil quality remained mostly unchanged (as shown by statistical analysis of GC-MS results). However, enzyme-assisted reflux extraction pretreatment did not significantly outperform reflux extraction (no-enzyme control), suggesting that the observed yield increase was mostly a consequence of reflux extraction and enzymatic activity had only a minute effect. Thus, we show that ultrasound and reflux extraction pretreatments are beneficial in the production of essential oils of selected Mediterranean plants, but the application of enzymes has to be carefully re-evaluated.
Istraživanja predstavljena u ovom preglednom radu doprinose poznavanju isparljivih organskih spojeva iz morskih organizama, posebno iz makroalgi Jadranskog mora. Za izolaciju isparljivih spojeva iz ...svježih i/ili na zraku osušenih uzoraka primijenjene su komplementarne metode: mikroekstrakcija vršnih para na čvrstoj fazi (HS-SPME) i/ili hidrodestilacija (HD). Dobiveni izolati analizirani su vezanim sustavom plinske kromatografije-spektrometrije masa (GC-MS). U vršnim parama i isparljivim uljima makroalgi Halopteris filicina, Flabellia petiolata, Dictyota dichotoma, Taonia atomaria, Padina pavonica, Codium bursa i morskoj cvjetnici Posidonia oceanica pronađeno je mnoštvo različitih spojeva, uglavnom seskviterpena, diterpena i alifatskih spojeva. Alifatski spojevi male molekulske mase, poput dimetil-sulfida (DMS), tribrommetana, 1-jodpentana, 3-metilbut-2-enala, heksanala i pent-1-en-3-ona, nađeni su u kemijskim profilima vršnih para. Također su identificirani i alifatski C8- i C11-spojevi (npr. oktan-l-ol, oktanal, okt-1-en-3-ol, 6-metilhept-5-en-2-on, fukoseraten i diktioptereni). Zajedno s višim acikličkim ugljikovodicima, također pronađenim u vršnim parama (npr. heptadekan), u ispitivanim isparljivim uljima identificirani su i viši alifatski alkoholi (npr. (Z)-oktadec-9-en-1-ol, heksadekan-1-ol, (Z,Z)-oktadeka-3,13-dien-1-ol) i esteri (npr. diizooktil-ftalat, dibutil-ftalat). Fenilpropanski derivati (npr. benzaldehid, benzil-alkohol) i C13-norizporenoidi (npr. α-jonon i β-jonon) također su pronađeni u isparljivim profilima, kao i mnoštvo seskviterpena (npr. germakren D, biciklogermakren, δ-kadinen, epizonaren, epibicikloseskvifelandren, β-kubeben, gleenol, (E)-β-farnezen). Isparljivi organski spojevi identificirani u morskim algama mogu poslužiti u kemotaksonomskim istraživanjima.
Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna .
Two selected brown algae (
and
from the family Dictyotaceae, order Dictyotales) growing in the same area (island Vis, central Adriatic Sea) were collected at the same time. Their phytochemical ...composition of the headspace volatile organic compounds (HS-VOCs; first time report) was determined by headspace solid-phase microextraction (HS-SPME). Hydrodistillation was applied for the isolation of their volatile oils (first report on
volatile oil). The isolates were analyzed by gas chromatography (GC-FID) and mass spectrometry (GC-MS). The headspace and oil composition of
were quite similar (containing germacrene D, epi-bicyclosesquiphellandrene, β-cubebene and gleenol as the major compounds). However,
headspace and oil composition differed significantly (dimethyl sulfide, octan-1-ol and octanal dominated in the headspace, while the oil contained mainly higher aliphatic alcohols,
-phytol and pachydictol A). Performed research contributes to the knowledge of the algae chemical biodiversity and reports an array of different compounds (mainly sesquiterpenes, diterpenes and aliphatic compounds); many of them were identified in both algae for the first time. Identified VOCs with distinctive chemical structures could be useful for taxonomic studies of related algae.
Various mint taxa are widely cultivated and are used not only for medicinal purposes but also in cosmetic and industrial applications. The development of new varieties or cultivars of mint generates ...difficulties in their correct identification and safe use. Volatile organic compounds (VOCs) from the leaves of seven different taxa of the genus Mentha obtained by hydrodistillation (HD) and headspace solid-phase microextraction (HS-SPME) were analyzed using gas chromatography–mass spectrometry (GC-MS). Principal component analysis (PCA) was also performed. Comparative GC-MS analysis of the obtained extracts showed similarity in the major compounds. PCA data allowed the separation of two groups of chemotypes among the analyzed mints, characterized by the abundance of piperitenone oxide and carvone. Two out of seven analyzed taxa were not previously examined for VOC profile, one was examined only for patent application purposes, and six out of seven were investigated for the first time using the HS-SPME technique. The presented analysis provides new data on the abundance and qualitative characterization of VOCs in the studied mint plants and on the safety of their use, related to the possibility of the presence of potentially toxic components. HS-SPME is a valuable method to extend the characterization of the VOC profile obtained by hydrodistillation.
Performed phytochemical study contributes to the knowledge of volatile organic compounds (VOCs) of Halopteris filicina (Grateloup) Kützing, Dictyota dichotoma (Hudson) J. V. Lamouroux, Posidonia ...oceanica (L.) Delile and Flabellia petiolata (Turra) Nizamuddin from the Adriatic Sea (single point collection). VOCs were investigated by headspace solid-phase microextraction (HS-SPME) and analysed by gas chromatography and mass spectrometry (GC-MS/FID). H. filicina headspace contained dimethyl sulfide (DMS; 12.8%), C8-compounds (e.g. fucoserratene (I; 9.5%)), benzaldehyde (II; 8.7%), alkane C17, dictyopterene D and C (III, IV), tribromomethane (V), 1-iodopentane, others. F. petiolata headspace was characterized by DMS (22.2%), 6-methylhept-5-en-2-one (9.5%), C17 (9.1%), II (6.5%), compounds I-V. DMS (59.3%), C15 (14.5%), C17 (7.2%) and C19 (6.3%) dominated in P. oceanica headspace. Sesquiterpenes were found in D. dichotoma, predominantly germacrene D (28.3%) followed by other cadinenyl (abundant), muurolenyl and amorphenyl structures. Determined VOCs may be significant for chemosystematics and chemical communications in marine ecosystem.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Reviewed in brief are the selected results of the application of headspace solid-phase microextraction as a preparative approach for gas chromatography – mass spectrometry (HS-SPME/GC-MS) for natural ...organic compounds research at the University of Split, Faculty of Chemistry and Technology. A wide variety of headspace compounds from different natural sources has been identified: lower aliphatic compounds (
e.g.
, C5- and C6-compounds), aromatic compounds, monoterpenes (
e.g.
, linalool derivatives (oxides, anhydro-oxides, epoxides), hotrienol), sesquiterpenes (
e.g.
, eudesmol isomers, hydrocarbons), and C9- and C13-norisoprenoids (
e.g.
, 3,4-dihydro-3-oxoedulan, 4-oxoisophorone,
trans
-β-damascenone). These compounds are important phytochemicals as flavour/fragrance compounds, chemical markers of the botanical origin or others (
e.g.
, allelochemicals, pheromones, or acaricide residue).
Ukratko su prikazani odabrani rezultati primjene mikroekstrakcije vršnih para na čvrstoj fazi kao preparativnog pristupa plinskoj kromatografiji – spektrometriji masa (HS-SPME/GC-MS) za istraživanje prirodnih spojeva, koje je provedeno na Kemijsko-tehnološkom fakultetu Sveučilištu u Splitu. Velika raznolikost spojeva vršnih para istražena je iz različitih prirodnih izvora: niži alifatski spojevi (npr. C5- i C6-spojevi), aromatski spojevi, monoterpeni (npr. derivati linaloola (oksidi, anhidro-oksidi, epoksidi), hotrienol), seskviterpeni (npr. eudezmol izomeri, ugljikovodici) te C9- i C13-norizoprenoidi (npr. 3,4-dihidro-3-oksoedulan, 4-oksoisoforon,
trans
-β-damascenon). Ti su spojevi važne fitokemikalije kao spojevi aroma/mirisa, kemijski marker botaničkog podrijetla ili drugo (npr. aleokemikalije, feromoni ili ostatci akaricida).
The aim of this study was to develop an innovative sheep cheese enriched with Thymus capitatus L. essential oil (EO) nanoincorporated into small homogeneous liposomes. The latter were prepared using ...two types of lecithin: one commonly used for liposome production, and the other used as dietary supplement. Both EO liposomes, which showed similar physico-chemical characteristics (i.e., size, homogeneity, surface charge), were incorporated into fresh sheep cheese. These enriched sheep cheeses were produced in Sardinia (Italy) and analysed 20, 60 and 180 days after preparation. HS-SPME at 40 and 80 °C coupled with GC-MS/FID method was used to evaluate the volatile fraction and identify the main compounds of both EO and cheese. A validated HPLC-DAD analysis allowed the identification and quantification of thymol and carvacrol, and thymol amount dosed at 20 days was the highest (9.51–10.10 mg/kg). The amount of monoterpenoid phenols and the antiradical and total antioxidant capacity evaluated by FRAP and DPPH• assays, decreased linearly (r ≥ 0.93, p ≤ 0.05) as the cheese maturation increased. Overall results suggested that sheep cheese enriched with T. capitatus EO nanoformulations had an enhanced antioxidant activity compared to cheese without liposomal EO, up to 180 days.
•An innovative enriched sheep cheese was developed.•Thymus capitatus L. essential oil was nanoincorporated in liposomes.•Thymol amount in cheese at 180 days ranged between 2.53 and 3.53 mg/kg.•Antiradical and total antioxidant capacities were enhanced until 180 days.
A study on the headspace volatile organic compounds (VOCs) profile of native populations of Sideritis romana L. and Sidertis montana L., Lamiaceae, from Croatia is reported herein, to elucidate the ...phytochemical composition of taxa from this plant genus, well-known for traditional use in countries of the Mediterranean and the Balkan region. Headspace solid-phase microextraction (HS-SPME), using divinylbenzene/carboxene/polydimethylsiloxane (DVB/CAR/PDMS) or polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber, coupled with gas chromatography-mass spectrometry (GC-MS) was applied to analyze the dried aerial parts of six native populations in total. Furthermore, principal component analysis (PCA) was conducted on the volatile constituents with an average relative percentage ≥1.0% in at least one of the samples. Clear separation between the two species was obtained using both fiber types. The VOCs profile for all investigated populations was characterized by sesquiterpene hydrocarbons, followed by monoterpene hydrocarbons, except for one population of S. romana, in which monoterpene hydrocarbons predominated. To our knowledge, this is the first report on the VOCs composition of natural populations of S. romana and S. montana from Croatia as well as the first reported HS-SPME/GC-MS analysis of S. romana and S. montana worldwide.
The use of deficit irrigation techniques on olive orchards is the main trend aiming to optimize water savings while improving functional and sensory characteristics of oils from trees under deficit ...irrigation techniques. The brand
has been defined for crops produced under water restriction conditions.
olive oils obtained under two new regulated deficit irrigation and one sustained deficit irrigation treatments in "Arbequina" olive trees were evaluated by analyzing quality parameters, antioxidant activity, total phenol content, fatty acid profile, volatile compounds, and sensory descriptors. Results showed that some of these irrigation strategies improved the phenol content at "moderate" stress levels, slightly enriched the fatty acid profile (~3.5% increased oleic acid and simultaneously decreased saturated fatty acids), and increased some key volatile compounds and also several key sensory attributes. Therefore,
olive oil may be more attractive to consumers as it is environmentally friendly, has a higher content of several bioactive compounds, and has improved sensory characteristics as compared to control (fully irrigated) oils.
Rosemary (
L.) is a Mediterranean medicinal and aromatic plant widely used due to valuable bioactive compounds (BACs) and aromas. The aim of the study was to evaluate the extraction of intracellular ...compounds from rosemary combining experimental procedure by means of high voltage electrical discharge (HVED), with a theoretical approach using two computational simulation methods: conductor-like screening model for real solvents and Hansen solubility parameters. The optimal HVED parameters were as follows: frequency 100 Hz, pulse width 400 ns, gap between electrodes 15 mm, liquid to solid ratio 50 mL/g, voltage 15 and 20 kV for argon, and 20 and 25 kV for nitrogen gas. Green solvents were used, water and ethanol (25% and 50%). The comparison was done with modified conventional extraction (CE) extracted by magnetic stirring and physicochemical analyses of obtained extracts were done. Results showed that HVED extracts in average 2.13-times higher total phenol content compared to CE. Furthermore, nitrogen, longer treatment time and higher voltage enhanced higher yields in HVED extraction. HVED was confirmed to have a high potential for extraction of BACs from rosemary. The computational stimulation methods were confirmed by experimental study, ethanol had higher potential of solubility of BACs and aromas from rosemary compared to water.
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