Daniele Giuffrida

Characterization of 12 Capsicum varieties by evaluation of their carotenoid profile and pungency determination.

In this research 12 different varieties of Capsicum cultivars belonging to three species (Capsicum chinense, Capsicum annuum, Capsicum frutescens) and of various colour, shape, and dimension have been characterised by their carotenoids and capsaicinoids content. The berries were cultivated in the region Emilia-Romagna, in Northern Italy. The native carotenoid composition was directly investigated by an HPLC-DAD-APCI-MS methodology, for the first time. In total, 52 carotenoids have been identified and considerable variation in carotenoid composition was observed among the various cultivars investigated. Among the cultivars with red colour, some Habanero, Naga morich and Sinpezon showed an high β-carotene content, whereas Serrano, Tabasco and Jalapeno showed an high capsanthin content and the absence of β-carotene. Habanero golden and Scotch Bonnet showed a high lutein, α-carotene and β-carotene amounts, and Habanero orange was rich in antheraxanthin, capsanthin and zeaxanthin. Cis-cryptocapsin was present in high amount in Habanero chocolate. The qualitative and quantitative determination of the capsaicinoids, alkaloids responsible for the pungency level, has also been estimated by a validated chromatographic procedure (HPLC-DAD) after a preliminary drying step and an opportune extraction procedure. Results have also been expressed in Scoville units. Dry matter and water activity have also been established on the fresh berries. The dried peppers of each variety were then submitted to the evaluation of the total nitrogen content, measured by a Dumas system, permitting to provide information on the protein content that was found to be in the range between 7 and 16%.

Comprehensive normal-phase × reversed-phase liquid chromatography coupled to photodiode array and mass spectrometry detection for the analysis of free carotenoids and carotenoid esters from mandarin

In the present work, a novel strategy including the use of two different comprehensive HPLC methods has been employed to study the whole carotenoid composition of mandarin essential oil. Thus, two different fully orthogonal two-dimensional HPLC methods have been used. A silica microbore column was coupled to a C(18) monolithic column to study the mandarin saponified extract, while the coupling of a cyano microbore column to a C(18) monolithic column was employed to study the intact mandarin essential oil sample in order to characterize the native carotenoid esters composition. Detection was performed by connecting a photodiode array detection (DAD) system in parallel with a MS detection system operated with an atmospheric pressure chemical ionization (APCI) interface. Thus, the carotenoid identification was carried out by combining the information provided by the DAD and MS systems and the peaks relative position in the two-dimensional chromatograms.

The structure-directed synthesis of cyclacene and polyacene derivatives

The treble diastereoselectivities exhibited by Diels-Alder reactions which occur between diene and dienophilic components associated with bicyclic systems have been employed in the stepwise construction of compounds with molecular architectures that resemble cups and cages. These macropolycyclic compounds are potential synthetic precursors of novel hydrocarbons composed of (a,d)-fused and (a,c)-fused six-membered rings. The hydrocarbons themselves are of considerable importance in investigating the behaviour of x-electrons in highly-conjugated cyclic systems and in understanding the influence upon the aromaticity and antiaromaticity of benzenoid and fused benzenoid rings that are obliged to become bent.

Ultra high pressure in the second dimension of a comprehensive two-dimensional liquid chromatographic system for carotenoid separation in red chili peppers.

A comprehensive normal-phase × reversed-phase (NP-LC × RP-LC) liquid chromatography system was developed, and applied for analysis of the intact carotenoid composition of red chili peppers, with photodiode array and mass spectrometry detection. A micro-bore cyano column (250 mm × 1.0 mm, 5 μm d.p.) was chosen for the first dimension ((1)D) separation, interfaced to a second dimension ((2)D) C18 column (30 mm × 4.6 mm, 2.7 μm d.p.) packed with fused-core particles. Subsequently, two columns of the same stationary phase were coupled serially for second dimension separation, and operated under ultra high pressure LC conditions (UHPLC), within a cycle time of 1.50 or 1.00 min, and equal modulation times. Performances of the three different set-ups were evaluated, in terms of peak capacity values (n(c)), and afterwards corrected by taking into account both the under-sampling, and the orthogonality effects. After these adjustments, the peak capacity values were estimated as follows: n(c) 526, for the NP-LC × RP-LC system, n(c) 373, for the NP-LC × RP-UHPLC system with a 1.50 min modulation time, n(c) 639, for the NP-LC × RP-UHPLC system, with a 1.00 min modulation time. A total of 33 compounds were separated into 10 different chemical classes in the two-dimensional space, and identified by accurate IT-TOF (ion trap-time of flight) MS detection.

Native carotenoids composition of some tropical fruits

Many tropical fruits can be considered a reservoir of bioactive substances with a special interest due to their possible health-promoting properties. The interest in carotenoids from a nutritional standpoint has recently greatly increased, because of their important health benefits. Here we report the native carotenoids composition in six tropical fruits from Panama, which is considered a region of great biodiversity. The native carotenoid composition was directly investigated by an HPLC-DAD-APCI-MS methodology, for the first time. In Corozo 32 different carotenoids were detected, including a high content of β-carotene and lycopene. Sastra showed the highest content of zeaxanthin among the fruit investigated. In Sapote 22 different carotenoids were detected, including β-carotene and 10 different zeaxanthin-di-esters. Frutita showed a very high content of the apo-carotenoid β-citraurin, and of a number of its esters. In Maracuyà chino 14 carotenoids were detected, including a high amounts of mono-esterified lauric acid with β-cryptoxanthin and with cryptocapsin. Mamey rojo was characterised by ketocarotenoids with κ rings, both hydroxylated and not hydroxylated.

Epoxycarotenoids esters analysis in intact orange juices using two-dimensional comprehensive liquid chromatography

In this work, the native carotenoid pattern of different orange juices was studied by LC x LC-DAD/APCI-IT-TOF-MS for the first time. Special attention was given to the epoxycarotenoids components. It has been already proposed that the relative proportions and composition of these epoxycarotenoids can be used to estimate the age and freshness of an orange juice. Re-arrangements from 5,6- to 5,8-epoxides can occur with time, partially due to the natural acidity of the juices. Thus, the study of these carotenoids in their intact form, that is, esterified with fatty acids, is of great interest. Besides, other free carotenoid and carotenoids esters were identified in seven different monovarietal orange juices and a commercial orange juice. Moreover, the higher separation power of the present LC x LC approach allowed a clearer identification of the compounds contained in the sample compared to the more commonly used approach which uses C(30) stationary phases in conventional LC, thanks to the attainment of clearer MS spectra due to the higher resolution and separation degree obtained in LC x LC. This method could also be used to establish authenticity markers among orange varieties that could be potentially used to prevent or detect adulterations or to establish ripeness indexes.

Serial coupled columns reversed-phase separations in high-performance liquid chromatography Tool for analysis of complex real samples

High-performance liquid chromatography is considered as the selected analytical tool for a huge number of applications, including the carotenoid analysis. However, due to the great complexity of some natural samples containing this kind of compounds, conventional LC could not have enough separation power. In this work, serial connection of several columns is proposed as an alternative to LC and also to comprehensive two-dimensional LC for the analysis of carotenoids from complex real matrices. Different parameters regarding these separation procedures are studied and discussed, such as the stationary phase used or the application of high separation temperatures. The applicability of connecting two C30 columns to significantly increase the separation power, resolution and peak capacity for the analysis of carotenoids has been demonstrated for the first time. In fact, a peak capacity of 79 was obtained when using two C30 serial coupled columns, compared to 61 achieved using a single column. Similar improvements were also observed for the other serial couplings studied. The present methodology could be applied to the analysis of carotenoids in a great variety of samples. To the best of our knowledge, this is the first development carried out to study natural products such as carotenoids using columns coupled in series.

Analysis of native carotenoid composition in orange juice using C30 columns in tandem

In the present contribution, a novel analytical approach based on using serial coupled conventional LC columns is proposed to the study of the native carotenoid composition of orange juice. The great difficulties that are found when analyzing complex carotenoid samples, due to the high natural variability of these compounds as well as to the presence of carotenoid esters are well documented. To overcome some of these limitations, we have developed a methodology including the study of both the saponified and the intact sample by means of two different LC-DAD/APCI-MS methods. The increase in the resolution and separation power obtained when using two serial coupled C(30) columns is demonstrated, and significant increases in peak capacity have been achieved. By using this new methodology, 44 different carotenoids have been tentatively identified. Among them, several violaxanthin diesters have been directly identified in orange juice for the first time. The main carotenoids in orange juice were violaxanthin, lutein, luteoxanthin, 9-cis-antheraxanthin, and beta-cryptoxanthin. Some of them were found in both their free and esterified forms. To the best of our knowledge, this is the first application of serial couplings of C(30) columns for the identification of the native carotenoid composition of natural matrices.

Lipid composition of Geotrichum candidum single cell protein grown in continuous submerged culture

Abstract Continuous cultivation of Geotricum candidum grown on orange peel extracts produced a high-protein, low-lipid content single cell protein which could be utilized as feed or proteic extract source. The lipid content, ca 4%, was very low compared with the data available in the literature, a result which might be attributed to the fermentation conditions employed in this study. The lipid composition of the dried biomass of this fungus is reported and briefly discussed.

Determination of Carotenoids and their Esters in Fruits of Sea Buckthorn (Hippophae rhamnoides L.) by HPLC-DAD-APCI-MS

INTRODUCTION The berries of Hippophae rhamnoides Linnaeus have high nutritional and medicinal values and have been used for centuries as food both in Europe and Asia. The oleoresins represent a potential source of carotenoid esters and can be used as food additives, cosmetic ingredients or nutraceuticals. OBJECTIVE The objective of this study was to develop a HPLC-DAD-APCI-MS method, with both positive and negative ionisation modes, for the direct identification of the native carotenoid composition in fruits of Hippophae rhamnoides. MATERIALS AND METHODS Fruits of Hippophae rhamnoides, cv. Serbanesti and Victoria, were collected from an experimental field at the Fruit Research Station of Bacau, Romania. Samples were extracted using methanol:ethyl acetate:petroleum ether (1:1:1, v/v/v). The HPLC-DAD-APCI-MS analyses were carried out on a Shimadzu system using a YMC C₃₀-column and a gradient elution. RESULTS In total 22 compounds were detected, eight were free carotenoids, nine were xanthophylls monoesters and five were xanthophylls diesters. Differences were observed in the relative percentage composition of the identified components among the two cultivars investigated. Zeaxanthin-C16:0,C16:0 was the most abundant diester. The unsaturated palmitoleic acid was directly detected in its esterified form, in zeaxanthin-C16:0,C16:1, which is reported here for the first time. Although present in small amounts the unsaturated oleic, linoleic, linolenic, hexadecadienoic and hexadecatrienoic acids were detected in their esterified forms as lutein monoesters, the last two having been detected in Hippophae rhamnoides for the first time. CONCLUSION A novel (HPLC-DAD-APCI-MS) method was developed for the direct identification of the native carotenoid composition in fruits of Hippophae rhamnoides.