Determination of falcarinol in carrot (Daucus carota L.) genotypes using liquid chromatography/mass spectrometry

Divergent fatty acid desaturase 2 is essential for falcarindiol biosynthesis in carrot

Carrots produce diverse falcarin-type polyacetylenes (PAs), which function as important antipathogenic phytoalexins and have potential as anticancer agents. Despite their abundance in carrot root tissues, the biosynthesis and evolutionary origins of falcarindiol, a C17-PA, remain unknown. Fatty acid desaturase 2 (FAD2) enzymes diversify PAs by introducing various double and/or triple carbon-carbon bonds into fatty acid chains. Here, we use association analysis to identify candidate FAD2 genes involved in falcarindiol biosynthesis. Using a rapid tobacco transient expression system, we found that DcFAD2 enzymes are highly functionally redundant and promiscuous. Combinatorial assays also revealed unexpected synergistic and redirective effects among FAD2 enzymes, further complicating the biosynthetic pathway. CRISPR-Cas9-mediated mutagenesis and overexpression studies identified previously overlooked DcFAD2 hub genes as essential for falcarindiol production. Evolutionary analysis suggests that the expansion of DcFAD2 genes underpins the abundance of falcarindiol in carrot, independent of the biosynthetic gene cluster previously identified in tomato. This work underscores the complexity of the falcarin biosynthetic network and identifies hub genes essential for falcarindiol biosynthesis in carrot.

Essential Oils of Ferulago glareosa Kandemir&Hedge Roots and Aerial Parts: PCA and HCA Analyses

Ferulago glareosa Kandemir & Hedge. is an endemic species of the family Apiaceae for Turkey and has interesting morphological characteristics compared to the other members of the genus Ferulago Koch. In this study we investigated the essential oil compositions of the roots and aerial parts of F. glareosa for the first time and compared them with essential oil compositions of the roots and aerial parts of other species of the genus. In our study, major components of the essential oil of the roots were determined to be 2,3,6-trimethylbenzaldehyde (32.2 %), falcarinol (23.7 %), hexadecanoic acid (9.5 %) and 2,5-dimethoxy-p-cymene (5.9 %); and major components of the essential oil of the aerial parts were found to be α-pinene (33.7 %), p-cymene (14.8 %), γ-terpinene (13.2 %), (Z)-β-ocimene (12.4 %) and terpinolene (8.2 %). The essential oil compositions of F. glareosa root compare with essential oils components in the literature differ varies greatly. Hierarchical Cluster Analysis (HCA) was performed with Minitab software, utilizing 8 major components in the published 20 literatures, as well as in this study. Principal Component Analyses (PCA) were used in order to demonstrate chemotaxonomical variations in the composition of the essential oils of Ferulago species.

Quantification of the anti-neoplastic polyacetylene falcarinol from carrots in human serum by LC-MS/MS

Falcarinol is a polyacetylene which is found in carrots and known to have anti-neoplastic properties in rodents. Research in the bioactivity of falcarinol in humans require methods for quantification of falcarinol in human serum. Here we report the development of an LC-MS/MS method and its use to measure serum falcarinol concentrations in humans following intake of a carrot product. Falcarinol was measured by LC-MS/MS using the m/z 268 to m/z 182 mass transition. Six calibrator levels (0.2-20 ng/mL) and 3 control levels (0.4, 2 and 8 ng/mL) were prepared by addition of falcarinol to human serum pools. Linearity of the developed method was good with a mean R² of 0.9942. Within-day, between-day and total coefficients of variation were 6.9-13.1%, 4.1-5.0% and 8.1-14.0%, respectively. The limits of detection and quantitation were 0.1 and 0.2 ng/mL, respectively, matrix effects 84.2%, recovery 101.4-105.4% and carry-over -0.24-0.07%. Serum falcarinol concentrations were measured in 18 healthy volunteers prior to and at 9 time-points following intake of a carrot product. Falcarinol concentrations peaked at the 1-hour time-point after intake in 15 out of 18 volunteers and declined according to a single exponential decay function with an aggregate t_½ of 1.5 h. In conclusion, an LC-MS/MS method for quantification of falcarinol in human serum with acceptable performance was developed and used to measure falcarinol concentrations following intake of a carrot product.

Structural diversity, biosynthesis, and function of plant falcarin-type polyacetylenic lipids

The polyacetylenic lipids falcarinol, falcarindiol, and associated derivatives, termed falcarins, have a widespread taxonomical distribution in the plant kingdom and have received increasing interest for their demonstrated health-promoting properties as anti-cancer and anti-inflammatory agents. These fatty acid-derived compounds are also linked to plant pathogen resistance through their potent antimicrobial properties. Falcarin-type polyacetylenes, which contain two conjugated triple bonds, are derived from structural modifications of the common fatty acid oleic acid. In the past half century, much progress has been made in understanding the structural diversity of falcarins in the plant kingdom, whereas limited progress has been made on elucidating falcarin function in plant-pathogen interactions. More recently, an understanding of the biosynthetic machinery underlying falcarin biosynthesis has emerged. This review provides a concise summary of the current state of knowledge on falcarin structural diversity, biosynthesis, and plant defense properties. We also present major unanswered questions about falcarin biosynthesis and function.

High-Pressure Homogenization and Biocontrol Agent as Innovative Approaches Increase Shelf Life and Functionality of Carrot Juice

Recently, application of high-pressure homogenization (HPH) treatments has been widely studied to improve shelf life and rheological and functional properties of vegetable and fruit juices. Another approach that has drawn the attention of researchers is the use of biocontrol cultures. Nevertheless, no data on their possible combined effect on fruit juices shelf life and functionality have been published yet. In this work, the microbial, organoleptic, and technological stability of extremely perishable carrot juice and its functionality were monitored for 12 and 7 days (stored at 4 and 10 °C, respectively) upon HPH treatment alone or in combination with a fermentation step using the biocontrol agent L. lactis LBG2. HPH treatment at 150 MPa for three passes followed by fermentation with L. lactis LBG2 extended the microbiological shelf life of the products of at least three and seven days when stored at 10 °C and 4 °C, respectively, compared to untreated or only HPH-treated samples. Moreover, the combined treatments determined a higher stability of pH and color values, and a better retention of β-carotene and lutein throughout the shelf-life period when compared to unfermented samples. Eventually, use of combined HPH and LBG2 resulted in the production of compounds having positive sensory impact on carrot juice.

Physiological Roles of Red Carrot Methanolic Extract and Vitamin E to Abrogate Cadmium-Induced Oxidative Challenge and Apoptosis in Rat Testes: Involvement of the Bax/Bcl-2 Ratio

The precise analysis of the contents of the red carrot is still ambiguous and its role in the maintenance of male fertility needs to be further reconnoitered. Hence, this study targets the physiological impacts of either red carrot methanolic extract (RCME) or vitamin E (Vit. E), co-administrated with cadmium chloride (CdCl₂) on rat testes, specifically those concerned with apoptosis and oxidative challenge. Four groups of adult male rats (n = 12) are used; control, CdCl₂, CdCl₂ + Vit. E and CdCl₂ + RCME. LC-MS analysis of RCME reveals the presence of 20 different phytochemical compounds. Our data clarify the deleterious effects of CdCl₂ on testicular weights, semen quality, serum hormonal profile, oxidative markers and Bax/Bcl-2 ratio. Histopathological changes in testicular, prostatic and semen vesicle glandular tissues are also observed. Interestingly, our data clearly demonstrate that co-administration of either RCME or Vit. E with CdCl₂ significantly succeeded in the modulation (p < 0.05) of all of these negative effects. The most striking is that they were potent enough to modulate the Bax/Bcl-2 ratio as well as having the ability to correct the impaired semen picture, oxidant status and hormonal profile. Thus, RCME and Vit. E could be used as effective prophylactic treatments to protect the male reproductive physiology against CdCl₂ insult.

Ion-Mobility-Based Liquid Chromatography-Mass Spectrometry Quantitation of Taste-Enhancing Octadecadien-12-ynoic Acids in Mushrooms

For the accurate quantitation of kokumi-enhancing and bitter-tasting octadecadien-12-ynoic and octadecadienoic acids in chanterelles (Cantharellus cibarius Fr.), a sensitive ultra-high-performance liquid chromatography-differential ion mobility spectrometry-tandem mass spectrometry method was developed. On the basis of these quantitative data and the taste thresholds, dose-over-threshold factors were calculated to determine the contribution of these sensometabolites to the kokumi and bitter taste of chanterelles; e.g., 14,15-dehydrocrepenynic acid (3) and (9Z,15E)-14-oxooctadeca-9,15-dien-12-ynoic acid (7) were identified as key kokumi substances in raw chanterelles. Quantitative profiling of these compounds in various mushroom species demonstrated a unique accumulation of octadecadien-12-ynoic acids in Cantharellus. Furthermore, storage experiments highlighted dynamic processes, including the biosynthesis of these substances as a result of lipid peroxidation mechanisms.

Quantitative seasonal variation of the falcarinol-type polyacetylene (3S)-16,17-didehydrofalcarinol and its spatial tissue distribution in Tridax procumbens

INTRODUCTION

(3S)-16,17-Didehydrofalcarinol (1) has been isolated from Tridax procumbens and has proved to have notorious bioactivity against Leishmania mexicana. In this study, hexane fractions obtained from the methanol extract of each plant part (roots, stems, leaves, flowers, and fruits) of T. procumbens collected monthly during a year were analysed in order to determine the quantity of 1 associated with biotic variables.

OBJECTIVE

The aim of this study was to find the season of the year in which the bioactive metabolite 1 is at the highest concentration and to correlate it with temperature, length of day light, and rainfall.

METHODS

Hexane fractions were obtained by liquid-liquid extraction and an accurate quantitation of 1 was performed using gas chromatography with a flame ionisation detector (GC-FID) employing pelargonic acid vanillyl amide (2) as internal standard. Partial validation was based on linearity and precision.

RESULTS

Our results indicated that the total content of 1 has significant variation (P ≤ 0.05) during the different collecting months. The total content of the metabolite reached its highest level in the roots of the plant during June in the rainfall season (0.0358 ± 0.001 mg/g), and its lowest values in February and March during the drought season (0.0015 ± 0.000 and 0.0008 ± 0.000 mg/g, respectively).

CONCLUSION

Our study provided evidence that the content of 1 in roots is strongly influenced by the variables of the harvesting season, also indicating that the biosynthesis of the active metabolite is enhanced during the warm and rainy months.

A Pathogen-Responsive Gene Cluster for Highly Modified Fatty Acids in Tomato

In response to biotic stress, plants produce suites of highly modified fatty acids that bear unusual chemical functionalities. Despite their chemical complexity and proposed roles in pathogen defense, little is known about the biosynthesis of decorated fatty acids in plants. Falcarindiol is a prototypical acetylenic lipid present in carrot, tomato, and celery that inhibits growth of fungi and human cancer cell lines. Using a combination of untargeted metabolomics and RNA sequencing, we discovered a biosynthetic gene cluster in tomato (Solanum lycopersicum) required for falcarindiol production. By reconstituting initial biosynthetic steps in a heterologous host and generating transgenic pathway mutants in tomato, we demonstrate a direct role of the cluster in falcarindiol biosynthesis and resistance to fungal and bacterial pathogens in tomato leaves. This work reveals a mechanism by which plants sculpt their lipid pool in response to pathogens and provides critical insight into the complex biochemistry of alkynyl lipid production.

Phytochemicals in Daucus carota and Their Health Benefits-Review Article

Carrots are a multi-nutritional food source. They are an important root vegetable, rich in natural bioactive compounds, which are recognised for their nutraceutical effects and health benefits. This review summarises the occurrence, biosynthesis, factors affecting concentration, and health benefits of phytochemicals found in Daucus carota. Two hundred and fifty-five articles including original research papers, books, and book chapters were analysed, of which one hundred and thirty articles (most relevant to the topic) were selected for writing the review article. The four types of phytochemicals found in carrots, namely phenolics, carotenoids, polyacetylenes, and ascorbic acid, were summarised. These chemicals aid in the risk reduction of cancer and cardiovascular diseases due to their antioxidant, anti-inflammatory, plasma lipid modification, and anti-tumour properties. Numerous factors influence the amount and type of phytochemicals present in carrots. Genotype (colour differences) plays an important role; high contents of α and β-carotene are present in orange carrots, lutein in yellow carrots, lycopene in red carrots, anthocyanins in the root of purple carrots, and phenolic compounds abound in black carrots. Carotenoids range between 3.2 mg/kg and 170 mg/kg, while vitamin C varies from 21 mg/kg to 775 mg/kg between cultivars. Growth temperatures of carrots influence the level of the sugars, carotenoids, and volatile compounds, so that growing in cool conditions results in a higher yield and quality of carrots, while higher temperatures would increase terpene synthesis, resulting in carrots with a bitter taste. It is worthwhile to investigate the cultivation of different genotypes under various environmental conditions to increase levels of phytochemicals and enhance the nutritional value of carrot, along with the valorisation of carrot by-products.

Effect of variety, soil fertility status and agronomic treatments on carrot mineral and phytochemical composition and consumer liking of flavor traits

BACKGROUND

The aim of this study was to investigate the effects of variety (Nantes and Imperator), soil fertility status (high and low) and agronomic treatments on yield and quality traits of carrot composition and sensory factors. The treatments compared synthetic nitrogen at conventionally recommended amounts with compost-sourced nitrogen (high and low rates) and a range of amendments (compost, compost tea, micronutrients and foliar treatments). Additionally, we intended to identify factors affecting polyacetylene accumulation in carrots, owing to the growing interest in their health effects and paucity of agronomic information on their bioaccumulation in carrots.

RESULTS

Imperator accumulated more minerals, produced more phytochemicals and had higher antioxidant capacity than Nantes, which had more carotenoids. However, consumers preferred the flavor of Nantes over Imperator. High-fertility soil produced carrots of superior nutritional quality than did low-fertility soil, regardless of year-of-application amendments, the effects of which were often variety-dependent. High soil biological activity was able to overcome low fertility status and stimulate greater yield. Carrot phosphorus was correlated with falcarindiol biosynthesis. Chlorogenic acid and falcarindiol were correlated with antioxidant capacity, but not falcarinol or total phenolic compounds.

CONCLUSION

Carrots were not strongly affected by agronomic treatments in terms of yield or phytochemical status; however, soil biological activity overcame a soil nutrient deficit in terms of yield. Phenolic compounds and antioxidant status were generally higher in the high-fertility site, whereas polyacetylenes were variety-dependent. Chlorogenic acid and falcarindiol were associated with antioxidant capacity, but not total phenolic compounds and carotenoids. © 2019 Society of Chemical Industry.

Anticalcifying effect of Daucus carota in experimental urolithiasis in Wistar rats

Background

Urolithiasis is a burgeoning disease that results from pathological biomineralization. Daucus carota L. is a widely consumed food crop with reported nephroprotective and diuretic activity. Its potential for Ashmari bhedan (destruction of stone/calculi) or treatment of urinary calculi has been explored traditionally. However, no scientific evidence is available to prove its antiurolithiatic efficacy. Moreover, establishing the antiurolithiatic effects of D. carota, an extensively consumed commodity with numerous health benefits, would provide a beneficial dietary measure for the prevention and cure of urolithiasis.

Objective

The study aimed at investigating in vivo antiurolithiatic potential of hydroethanolic extract of D. carota roots against calcium oxalate urolithiasis.

Materials and methods

Ethylene glycol and ammonium chloride induced hyperoxaluria model of urolithiasis in male Wistar rats was used for the study. Urine and serum parameters and, kidney histopathology was used to determine the antilithic efficacy of D. carota root extract.

Results

D. carota extract significantly ameliorated abnormal urinary levels of calcium, oxalate, phosphate, magnesium, citrate, protein and uric acid in lithogenic rats. Serum BUN, creatinine and uric acid levels; and calcium, phosphate and oxalate deposition in kidney tissue were also rendered normal following D. carota treatment. D. carota extract also prevented oxidative stress mediated renal tissue degeneration both prophylactically and curatively.

Conclusion

This study suggests antiurolithiatic effect of D. carota roots, which can be attributed to its anticrystallization property, ability to ameliorate urine and serum biochemistry and renal cellularity.

Volatile Molecule Profiles and Anti-Listeria monocytogenes Activity of Nisin Producers Lactococcus lactis Strains in Vegetable Drinks

This work aimed to evaluate the potential of 15 nisin producing Lactococcus lactis strains, isolated from dairy products, for the fermentation of soymilk and carrot juice. In particular, the acidification and the production of nisin in the food matrices were recorded. Moreover, three strains (LBG2, FBG1P, and 3LC39), that showed the most promising results were further scrutinized for their anti-Listeria monocytogenes activity and volatile molecules profile during fermentation of soymilk and carrot juice. Lactococcus lactis strains LBG2, FBG1P, and 3LC39 resulted the most interesting ones, showing rapid growth and acidification on both food matrices. The higher amounts of nisin were detected in soymilk samples fermented by the strain LBG2 after 24 and 48 h (26.4 mg/L). Furthermore, the rapid acidification combined with the production of nisin resulted in a strong anti-Listeria activity, reducing the pathogen loads below the detection limit, in carrot juice samples fermented by the strains LBG2 and FBG1P and in soymilk by the strain LBG2. The fermentation increased the presence of volatile molecules such as aldehydes and ketones with a positive impact on the organoleptic profile of both the fermented products. These results highlighted the interesting potential of three nisin producing L. lactis strains for the production of fermented carrot juice and soymilk. In fact, the fermentation by lactic acid bacteria, combined or not with other mild technologies, represents a good strategy for the microbiological stabilization of these products. Furthermore, the increase of molecules with a positive sensory impact, such as aldehydes and ketones, in the fermented products suggests a possible improvement of their organoleptic characteristics.

Correlations between Polyacetylene Concentrations in Carrot (Daucus carota L.) and Various Soil Parameters

This study assessed the concentrations of three falcarinol-type polyacetylenes (falcarinol, falcarindiol, falcarindiol-3-acetate) in carrots and the correlations between these and different soil traits. A total of 144 carrot samples, from three different harvests taken a single season, were analysed in terms of their polyacetylene concentrations and root development. On one of the harvesting occasions, 48 soil samples were also taken and analysed. The chemical composition of the soil was found to influence the concentrations of falcarinol-type polyacetylenes in carrots. When the total soil potassium level was 200 mg/100 g soil, the concentration of falcarindiol (FaDOH) in the carrot samples was 630 μg/g DW, but when carrots were grown in soil with a total potassium level of 300 mg/100 g soil, the FaDOH concentration in the carrots fell to 445 μg/g DW. Carrots grown in soils generally low in available phosphorus exhibited higher levels of falcarindiol if the soil was also low in available magnesium and calcium. The concentrations of polyacetylenes in carrots were positively correlated with total soil phosphorus level, but negatively correlated with total soil potassium level. Of the three polyacetylenes analysed, FaDOH concentrations were influenced most by changes in soil chemical composition.

Bioactive C₁₇-Polyacetylenes in Carrots (Daucus carota L.): Current Knowledge and Future Perspectives

C17-polyacetylenes (PAs) are a prominent group of oxylipins and are primarily produced by plants of the families Apiaceae, Araliaceae, and Asteraceae, respectively. Recent studies on the biological activity of polyacetylenes have indicated their potential to improve human health due to anticancer, antifungal, antibacterial, anti-inflammatory, and serotogenic effects. These findings suggest targeting vegetables with elevated levels of bisacetylenic oxylipins, such as falcarinol, by breeding studies. Due to the abundant availability, high diversity of cultivars, worldwide experience, and high agricultural yields, in particular, carrot (Daucus carota L.) genotypes are a very promising target vegetable. This paper provides a review on falcarinol-type C17-polyacetylenes in carrots and a perspective on their potential as a future contributor to improving human health and well-being.

Exploring the effects of pulsed electric field processing parameters on polyacetylene extraction from carrot slices

The effects of various pulsed electric field (PEF) parameters on the extraction of polyacetylenes from carrot slices were investigated. Optimised conditions with regard to electric field strength (1–4 kV/cm), number of pulses (100–1500), pulse frequency (10–200 Hz) and pulse width (10–30 μs) were identified using response surface methodology (RSM) to maximise the extraction of falcarinol (FaOH), falcarindiol (FaDOH) and falcarindiol-3-acetate (FaDOAc) from carrot slices. Data obtained from RSM and experiments fitted significantly (p < 0.0001) the proposed second-order response functions with high regression coefficients (R²) ranging from 0.82 to 0.75. Maximal FaOH (188%), FaDOH (164.9%) and FaDOAc (166.8%) levels relative to untreated samples were obtained from carrot slices after applying PEF treatments at 4 kV/cm with 100 number of pulses of 10 μs at 10 Hz. The predicted values from the developed quadratic polynomial equation were in close agreement with the actual experimental values with low average mean deviations (E%) ranging from 0.68% to 3.58%.

Quality of carrots as affected by pre- and postharvest factors and processing

The aim of this review is to provide an update on factors contributing to quality of carrots, with special focus on the role of pre- and postharvest factors and processing. The genetic factor shows the highest impact on quality variables in carrots, causing a 7-11-fold difference between varieties in content of terpenes, β-carotene, magnesium, iron and phenolics as well as a 1-4-fold difference in falcarindiol, bitter taste and sweet taste. Climate-related factors may cause a difference of up to 20-fold for terpenes, 82% for total sugars and 30-40% for β-carotene, sweet taste and bitter taste. Organic farming in comparison with conventional farming has shown 70% higher levels for magnesium and 10% for iron. Low nitrogen fertilisation level may cause up to 100% increase in terpene content, minor increase in dry matter (+4 to +6%) and magnesium (+8%) and reduction in β-carotene content (-8 to -11%). Retail storage at room temperature causes the highest reduction in β-carotene (-70%) and ascorbic acid (-70%). Heat processing by boiling reduces shear force (-300 to -1000%) and crispiness (-67%) as well as content of phenolics (-150%), terpenes (-85%) and total carotenes (-20%) and increases the risk of furan accumulation. Sensory and chemical quality parameters of carrots are determined mainly by genetic and climate-related factors and to a minor extent by cultivation method. Retail temperature and storage atmosphere as well as heating procedure in processing have the highest impact in quality reduction.

Quantitative Raman spectroscopy for the analysis of carrot bioactives

Rapid quantitative near-infrared Fourier transform Raman analyses of the key phytonutrients in carrots, polyacetylenes and carotenoids, are reported here for the first time. Solvent extracts of 31 carrot lines were analyzed for these phytonutrients by conventional methods, polyacetylenes by GC-FID and carotenoids by visible spectrophotometry. Carotenoid concentrations were 0-5586 μg g(-1) dry weight (DW). Polyacetylene concentrations were 74-4846 μg g(-1) DW, highest in wild carrots. The polyacetylenes were falcarinol, 6-1237 μg g(-1) DW; falcarindiol, 42-3475 μg g(-1) DW; and falcarindiol 3-acetate, 27-649 μg g(-1) DW. Strong Raman bands for carotenoids gave good correlation to results by visible spectrophotometry. A chemometric model capable of quantitating carotenoids from Raman data was developed. A classification model for rapidly distinguishing carrots with high and low polyacetylene (limit of detection = 1400 μg g(-1)) concentrations based on Raman spectral intensity in the region of 2250 cm(-1) was produced.

Simultaneous metabolite fingerprinting of hydrophilic and lipophilic compounds in Echinacea pallida by high-performance liquid chromatography with diode array and electrospray ionization-mass spectrometry detection

In this study, a detailed phytochemical characterization of Echinacea pallida (Nutt.) Nutt. root extracts and dietary supplements was carried out for the first time by developing advanced chromatographic techniques, based on HPLC with diode array (DAD) and electrospray ionization-mass spectrometry (ESI-MS) detection (with ion trap and triple quadrupole mass analyzers), for the simultaneous analysis of hydrophilic and lipophilic secondary metabolites. The HPLC analyses were carried out on an Ascentis C(18) column (250 mm × 4.6 mm I.D., 5 μm), with a mobile phase composed by H(2)O and ACN both containing 0.1% formic acid, under gradient elution. The UV spectra, in combination with MS and MS/MS data, allowed the identification of fourteen compounds, including caffeic acid derivatives, polyacetylenes and polyenes, in the analyzed samples. MS and MS/MS data were discussed in detail and the typical fragmentation patterns of each class of secondary metabolites were identified. For the first time, a hydroperoxide intermediate was characterized as an oxidation product of one of E. pallida monocarbonylic acetylenes, providing a confirmation of the mechanism that leads to the generation of hydroxylated derivatives. The HPLC method was fully validated in agreement with ICH guidelines and then applied to real samples. The quantitative analysis indicated that there was a great variability in the amount of the active compounds in the dietary supplements containing E. pallida root extracts: the content of total caffeic acid derivatives ranged from 2.31 to 11.45 mg/g and the amount of total polyacetylenes and polyenes from 6.38 to 30.54 mg/g. In the analyzed samples, the most abundant caffeic acid derivative was found to be echinacoside. Regarding polyacetylenes and polyenes, the most representative compounds were found to be tetradec-(8Z)-ene-11,13-diyn-2-one, pentedeca-(8Z,11Z)-dien-2-one and pentadec-(8Z)-en-2-one. The developed method can be considered suitable for metabolite fingerprinting and quality control of E. pallida plant material and natural products.

Accelerated solvent extraction for natural products isolation

Accelerated solvent extraction (ASE(®)), first introduced in 1995, is an automated rapid extraction technique that utilizes common solvents at elevated temperature and pressure, and thereby increases the efficiency of extraction of organic compounds from solid and semisolid matrices. ASE(®) allows extractions for sample sizes 1-100 g in minutes, reduces solvent uses dramatically, and can be applied to a wide range of matrices, including natural products.

Spectroscopic studies on bioactive polyacetylenes and other plant components in wild carrot root

Polyacetylenes and other common plant components, such as starch, pectin, cellulose, and lignin, were studied in roots of the wild carrot (Daucus carota) subspecies D. carota subsp. gummifer and D. carota subsp. maximus by Raman spectroscopy. The components were measured in situ, directly in the plant tissue and without any preliminary sample preparation. The analysis was performed on the basis of the intense and characteristic key bands observed in the Raman spectrum. The two main carrot polyacetylenes falcarinol (1) and falcarindiol (2) have similar molecular structures, but their Raman spectra exhibit a small band shift in the symmetric -C≡C-C≡C- mode from 2258 cm⁻¹ to 2252 cm⁻¹. Quantum chemical calculations confirmed that the differences observed between the samples may be due to conformational and environmental changes. The polyacetylenes were also detected by Raman mapping, which visualized the distribution of the compounds across sections of carrot roots. The mapping technique was also applied to assess the distribution of lignin and polysaccharide compounds. The results showed the tissue-specific accumulation of starch and cell wall components such as lignin, pectin, and cellulose.

Characterisation of polyacetylenes isolated from carrot (Daucus carota) extracts by negative ion tandem mass spectrometry

The potential use of negative electrospray ionisation mass spectrometry (ESI-MS) in the characterisation of the three polyacetylenes common in carrots (Daucus carota) has been assessed. The MS scans have demonstrated that the polyacetylenes undergo a modest degree of in-source decomposition in the negative ionisation mode while the positive ionisation mode has shown predominantly sodiated ions and no [M+H](+) ions. Tandem mass spectrometric (MS/MS) studies have shown that the polyacetylenes follow two distinct fragmentation pathways: one that involves cleavage of the C3-C4 bond and the other with cleavage of the C7-C8 bond. The cleavage of the C7-C8 bond generated product ions m/z 105.0 for falcarinol, m/z 105/107.0 for falcarindiol, m/z 147.0/149.1 for falcarindiol-3-acetate. In addition to these product ions, the transitions m/z 243.2 → 187.1 (falcarinol), m/z 259.2 → 203.1 (falcarindiol), m/z 301.2 → 255.2/203.1 (falcarindiol-3-acetate), mostly from the C3-C4 bond cleavage, can form the basis of multiple reaction monitoring (MRM)-quantitative methods which are poorly represented in the literature. The 'MS(3) ' experimental data confirmed a less pronounced homolytic cleavage site between the C11-C12 bond in the falcarinol-type polacetylenes. The optimised liquid chromatography (LC)/MS conditions have achieved a baseline chromatographic separation of the three polyacetylenes investigated within 40 min total run-time.

Comparison of polyacetylene content in organically and conventionally grown carrots using a fast ultrasonic liquid extraction method

A rapid and sensitive analytical method for quantification of polyacetylenes in carrot roots was developed. The traditional extraction method (stirring) was compared to a new ultrasonic liquid processor (ULP)-based methodology using high-performance liquid chromatography-ultraviolet (HPLC-UV) and mass spectrometry (MS) for identification and quantification of three polyacetylenes. ULP was superior because a significant reduction in extraction time and improved extraction efficiencies were obtained. After optimization, the ULP method showed good selectivity, precision [relative standard deviations (RSDs) of 2.3-3.6%], and recovery (93% of falcarindiol) of the polyacetylenes. The applicability of the method was documented by comparative analyses of carrots grown organically or conventionally in a 2 year field trial study. The average concentrations of falcarindiol, falcarindiol-3-acetate, and falcarinol in year 1 were 222, 30, and 94 mug of falcarindiol equiv/g of dry weight, respectively, and 3-15% lower in year 2. The concentrations were not significantly influenced by the growth system, but a significant year-year variation was observed for falcarindiol-3-acetate.