Quantitative evaluation of auraptene and umbelliferone, chemopreventive coumarins in citrus fruits, by HPLC-UV-FL-MS

Ameliorating effect of Citrus trifoliata L. fruits extract on motor incoordination, neurodegeneration and oxidative stress in Parkinson's disease model

BACKGROUND

Citrus trifoliate fruit (also known as Trifoliate orange) is one of the commercially-cultivated Citrus genus of plants belonging to the Rutaceae family. It has been traditionally-utilized in treatment of neurodegenerative disorders. However, the scientific evidence verifying this utilization needs further elucidation.

AIM OF THE STUDY

Characterization of the bioactive constituents of C. trifoliata L. fruits extract and evaluating its effect on Parkinson's disease (PD) model.

MATERIAL AND METHODS

Rats were classified into 5 groups; control, PD, PD-treated by L-dopa/Carpidopa and PD-treated by oral Citrus trifoliata L. fruits extract (50 and 100 mg/kg). Deterioration in brain functions was evaluated through an in vivo open field, grid and catalepsy tests. The study also assessed the striatal neurotransmitters, oxidative stress markers and histopathological changes.

RESULTS

Citrus trifoliata L. fruit extract has revealed motor improvement comparable to L-dopa and carbidopa. It has also effectively-improved oxidative stress via reduction of striatal malondialdehyde & nitric oxide along with replenishment of the striatal glutathione and superoxide dismutase. The extract caused significant reduction of the striatal myeloperoxidase activity and restoration of dopamine, γ-amino butyric acid (GABA), and acetylcholinesterase. This effect was further confirmed by amelioration of neuronal apoptosis, microgliosis and peri-neuronal vacuolation. Metabolite profiling revealed 40 constituents, with flavonoids representing the main identified class.

CONCLUSION

The neuro-protective effect of Citrus trifoliata extract was achieved through the antioxidant and anti-inflammatory activities of its flavonoids, particularly hesperidin and naringin. This neuro-protective effect was evident at the behavioral, histological and neurotransmitter levels.

Role and mechanism of fruit waste polyphenols in diabetes management

Among various diseases in humans, diabetes is one of the most complicated disorders resulting either from the malfunctioning of β cells, causing a poor discharge of insulin from them, or poor functioning of the liberated insulin. A wide array of chemical compounds so-called secondary metabolites are present in plants. These phytochemicals are produced as by-products of metabolism and play a key role in plant protection. However, in humans, they offer several beneficial functions. Polyphenols are an important class of phytochemicals and apart from fruits, they are also found in their major wastes mainly including the peel, pomace, and seed. The current review is aimed to focus on the potential sources, distribution, and extraction/isolation of polyphenols from major fruit wastes along with highlighting their medicinal and therapeutic benefits, especially in the management of diabetes.

High-performance liquid chromatography using diode array detector and fluorescence detector for hydrogen peroxide analysis in processed fishery foods

Hydrogen peroxide (H2O2) is a food additive for bleaching and sterilization, owing to its strong oxidizing effect. The current study aimed to develop analytical methods to detect trace amounts of residual H2O2 in diverse foods using high-performance liquid chromatography (HPLC) equipped with diode array detector (DAD) or fluorescence detector (FLD). The vanadium(V)-peroxo complex, derived from the reaction of H2O2 with ammonium metavanadate, was used for the detection of H2O2 with DAD. H2O2 was indirectly analyzed using FLD via the detection of 7-hydroxycoumarin, derived by Fenton reaction, followed by verification using liquid chromatography with tandem mass spectrometry analysis. Both the detection methods showed good linearity with R2 > 0.997. Limit of detection and limit of quantification were 0.30 and 0.91 mg/L (8.82 and 26.76 μM) with HPLC-DAD and 0.001 and 0.003 mg/L (0.03 and 0.09 μM) with HPLC-FLD, respectively. Applicability of both the methods was successively tested through sample analysis.

Chemical comparison and discrimination of two plant sources of Angelicae dahuricae Radix, Angelica dahurica and Angelica dahurica var. formosana, by HPLC-Q/TOF-MS and quantitative analysis of multiple components by a single marker

INTRODUCTION

Angelica dahurica(BZ) and Angelica dahurica var. formosana(HBZ) are two plant sources of Angelicae dahuricae Radix. Although BZ and HBZ are commonly used herbal medicines with great medicinal and dietary values, study on their phytochemicals and bioactive compositions is limited.

OBJECTIVE

To compare the chemical compositions of BZ and HBZ and find the chemical makers for discrimination and quality evaluation of the two botanical origins of Angelicae dahuricae Radix.

METHODOLOGY

A high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method was established for chemical profiling of BZ and HBZ. Then, a quantitative analysis of multiple components by a single marker method was developed for simultaneous determination of nine bioactive coumarins (xanthotoxol, oxypeucedanin hydrate, byakangelicin, xanthotoxin, bergapten, oxypeucedanin, phellopterin, imperatorin and isoimperatorin). Moreover, chemometrics were performed to compare and discriminate BZ and HBZ samples.

RESULTS

A total of 30 coumarins compounds were identified, and the chemical compositions in BZ and HBZ were quite similar. The quantitative analysis showed that there were significant differences in the contents of bioactive coumarins, and the chemometric analysis indicated five coumarins (xanthotoxol, xanthotoxin, bergapten, phellopterin and isoimperatorin) were responsible for the significant differences between BZ and HBZ, which could be used as chemical markers to distinguish the two original plant sources of Angelicae dahuricae Radix.

CONCLUSION

The present work provided useful information for understanding the chemical differences between BZ and HBZ and also provided feasible methods for quality evaluation and discrimination of herbal medicines originating from multiple botanical sources.

Bioguided Phytochemical Study of Ipomoea cairica Extracts with Larvicidal Activity against Aedes aegypti

Vector-borne diseases, such as those transmitted by Aedes aegypti, are a constant threat to inhabitants of tropical regions of the planet. Synthetic chemicals are commonly used as a strategy to control them; however, these products are known to persist in ecosystems and drive the appearance of resistance genes in arthropod vectors. Thus, the use of natural products has emerged as an environmentally friendly alternative in integrated vector control strategies. The present bioguided study investigated the larvicidal potential of Ipomoea cairica extracts, fractionated using thin-layer and open-column chromatography, because this species has been shown to exert larvicidal effects on the genus Aedes. The objective of this study was to evaluate the nonvolatile components in ethanolic extract of I. cairica stems as a potential natural larvicidal, and coumarins, such as 7-hydroxy-6-methoxychromen-2-one (scopoletin) and 7-hydroxychromen-2-one (umbelliferone), were identified as major compounds; however, they were not shown to be responsible for the larvicidal activity. Based on the results of the larvicidal action tests, these coumarins are not directly responsible for the larvicidal activity, but this activity might be attributed to a synergistic effect of all the compounds present in the most active secondary fraction, called F.DCM, which had an LC₅₀ value of 30.608 mg/L. This type of study has yet not been conducted in the region; therefore, it is an important contribution to recognizing a natural and easy-to-cultivate source of vector control, such I. cairica.

Safety and efficacy of a feed additive consisting of a flavonoid-rich dried extract of Citrus × aurantium L. fruit (bitter orange extract) for use in all animal species (FEFANA asbl)

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of a dried flavonoid-rich extract of Citrus × aurantium L. fruit (bitter orange extract), when used as a sensory additive for all animal species. The use of the additive in feed was not expected to increase the exposure to furocoumarins of those target species that are already fed citrus by-products to a relevant extent (< 5%). For dog, cat and ornamental fish, not normally exposed to citrus by-products, no conclusion could be drawn. The FEEDAP Panel concluded that the additive under assessment is safe up to the maximum proposed use level of 400 mg/kg for veal calf (milk replacer), sheep, goat, horse and salmon. For the other species, the calculated maximum safe concentration in complete feed is 102 mg/kg for chicken for fattening, 151 mg/kg for laying hen, 136 mg/kg for turkey for fattening, 182 mg/kg for piglet, 217 mg/kg for pig for fattening, 268 mg/kg for sow, 259 mg/kg for dairy cow and 161 mg/kg for rabbit. The FEEDAP Panel considered that the use in water for drinking is safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed, except dog, cat and ornamental fish. No concerns for consumer safety were identified following the use of the additive up to highest safe level in feed for the target animals. The extract under assessment should be considered as irritant to skin, eyes and the respiratory tract, and as a skin sensitiser. Since the additive contains 5-methoxypsoralen, it may cause phototoxicity. The use of the extract in animal feed under the proposed conditions was not expected to pose a risk for the environment. Bitter orange extract was recognised to flavour food. Since its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Safety and efficacy of feed additives consisting of expressed lemon oil and its fractions from Citrus limon (L.) Osbeck and of lime oil from Citrus aurantiifolia (Christm.) Swingle for use in all animal species (FEFANA asbl)

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of expressed lemon oil and distilled lemon oil from Citrus limon (L.) Osbeck and lime oil from Citrus aurantiifolia (Christm.) Swingle, when used as sensory additives in feed for all animal species. The use of the expressed lemon oil and its residual fraction and the use of lime oil in feed is not expected to increase the exposure to furocoumarins and methoxycoumarins and perillaldehyde of those target species that are already fed citrus by-products a relevant extent (< 10%). For companion animals and ornamental fish not normally exposed to citrus by-products, no conclusion can be drawn. For the other species and for the distilled fraction of expressed lemon oil, the FEEDAP Panel concludes that the additives under assessment are safe at the maximum proposed or at reduced use levels in complete feed. The Panel considers that the use in water for drinking is safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed. No concerns for consumer safety were identified following the use of the additives at the maximum proposed use level in feed. The additives under assessment should be considered as irritants to skin and eyes and the respiratory tract and as skin sensitisers. Since expressed lemon oil and its fractions contain furocoumarins, they may cause phototoxicity. The use of the additives under the proposed conditions of use in animal feed is not expected to pose a risk for the environment. Since C. limon and C. aurantiifolia and their preparations are recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy is considered necessary.

Limonoids isolated from fruits of Swietenia macrophylla king enhance glucose consumption in insulin-resistant HepG2 cells via activating PPARγ

The fruits of Swietenia macrophylla King have been processed commercially to a variety of health foods and healthcare products and exhibited antidiabetic, anti-inflammatory, antimutagenicity, antitumor activity, and so on. This study was aimed to examine the glucose consumption in human hepatoma HepG2 cells and the expression of PPARγ of limonoids isolated from the fruits of S. macrophylla. The phytochemical investigation of the fruits led to the isolation of ten limonoids which structures were elucidated by spectroscopic analysis as swietenine (1), khayasin T (2), 6-deoxyswietenine (3), 3-O-tigloylswietenolide (4), swietenolide (5), 3,6-O,O-diacetylswietenolide (6), 7-deacetoxy-7-oxogedunin (7), fissinolide (8), proceranolide (9), 7-deacetoxy-7α-hydroxygedunin (10), and compound 10 was isolated from this plant for the first time. The glucose consumption assay revealed that compounds 1, 2, 3, 5, and 9 could promote glucose consumption significantly in normal hyperglycemia-induced HepG2 cells, furthermore, compounds 1, 5, and 9 had a better effect on promoting glucose consumption in insulin-resistant HepG2 cells. In addition, compounds 1 and 5 could dramatically enhance the expression of PPARγ protein in insulin-resistant HepG2 cells according to the western blotting analysis result. PRACTICAL APPLICATIONS: Swietenia macrophylla King belongs to the family Meliaceae and the fruits have been exhibited a wide range of biological activities, such as antidiabetic, anti-inflammatory, antimutagenicity, antitumor activity, and so on. Phytochemical investigations of S. macrophylla have revealed that limonoids and triterpenoids were effective antidiabetic agents. However, the mechanism of these limonoids to antidiabetic activity is unclear. In this study, limonoids were isolated from the fruit of S. macrophylla and their effects on the glucose consumption of insulin-resistant HepG2 cells were studied. The results showed that compounds 1 and 5 could dramatically enhance the expression of PPARγ protein in insulin-resistant HepG2 cells, which will give aid to explore the mechanism of these limonoids in the treatment of type 2 diabetes. Therefore, this research might facilitate further research and development of S. macrophylla.

Progress in Pretreatment and Analytical Methods of Coumarins: An Update since 2012 - A Review

Coumarins are widely used due to their wide range of biological activities, but the long-term or excessive use of coumarin flavors can pose serious health hazards. Therefore, sensitive and specific methods for the quantification of these compounds in different matrices have been developed. In this review, an updated overview of the latest trends in sample preparation techniques and methods used to detect coumarins from March 2012 to April 2019 is provided. This study reviews different analytical methods (such as liquid chromatography coupled with different detectors, electrochemical sensors, capillary electrophoresis, etc.) and different pretreatment methods (such as liquid-liquid extraction, solid-phase extraction, dispersive liquid-liquid microextraction, etc.). Different methods for the pretreatment and determination of coumarins in plant, food, environmental, pharmaceutical and biological samples are summarized, discussed and compared.HighlightsProgress in pretreatment and analytical methods of coumarins are summarized.Fundamentals, instrumentation and applications of purification and quantification are summarized and compared.Optimization of experimental conditions are discussed.Newly emerged eco-friendly methods are introduced.

Botanical Sources, Chemistry, Analysis, and Biological Activity of Furanocoumarins of Pharmaceutical Interest

The aim of this work is to provide a critical review of plant furanocoumarins from different points of view, including their chemistry and biosynthetic pathways to their extraction, analysis, and synthesis, to the main biological activities found for these active compounds, in order to highlight their potential within pharmaceutical science. The limits and the possible improvements needed for research involving these molecules are also highlighted and discussed.

Analysis of Artemisia annua extracts and related products by high performance liquid chromatography-tandem mass spectrometry coupled to sample treatment miniaturisation

Artemisinin, the main antimalarial compound of Artemisia annua L., is currently attracting increasing interest for its antiproliferative properties, but its content is highly variable, depending on several genetic, environmental and processing conditions. Aim of the present study is to analyse the artemisinin content in different plant extracts, to test their in vitro activity on cell proliferation and then to correlate these data to the active principle concentration. For this purpose, an innovative miniaturised sample pretreatment strategy based on microextraction by packed sorbent (MEPS) was developed and coupled to an original advanced method based on liquid chromatography with diode array detection and tandem mass spectrometry (LC-DAD-MS/MS). The method was fully validated, granting consistent data. Good linearity was found over a suitable concentration range, i.e. 5-1000ng/mL. Extraction yields (>85%), precision (RSD < 3.5%) and accuracy (recovery 88-93%) were all within acceptable levels of confidence. After validation, the method was successfully applied to the determination of artemisinin in A. annua extracts. Analyte content was widely variable (up to twenty-fold) according to the starting material and the extraction procedure, ranging between 5.9μg/g and 109μg/mL. The cytotoxic activity of all analysed extracts was also tested on human leukemic cells by viable cell count and cell cycle analysis. Artemisinin concentrations and biological activity were carefully evaluated and the observed antiproliferative effects varied according to artemisinin content in each extract type. This highlights the need to quantitatively analyse the main active constituent of plant extracts and the obtained data have shown to be promising for the choice of the related herbal product dosage.

Analytical profiling of selected antioxidants and total antioxidant capacity of goji (Lycium spp.) berries

Goji berries and derived products represent a relevant source of micronutrients, most of which are natural antioxidants and contribute to the high nutritional quality of these fruits. Three brands of dried goji berries have been analysed by a multidisciplinary approach to get an insight into both their content of selected antioxidants and their antioxidant capacity (AC). The former goal has been achieved by developing a liquid chromatographic method coupled to mass spectrometry and combined to a fast solid phase extraction. Several significant representative antioxidant compounds belonging to the following classes: flavonoids, flavan-3-ols, phenolic acids, amino acids and derivatives, and carotenoids have been taken into account. Quercetin and rutin were found to be the predominant flavonoids, chlorogenic acid was the most abundant phenolic acid and zeaxanthin was the major carotenoid. The AC of the goji berries has been evaluated by four analytical methods in order to estimate the contributions of different reactions involved in radicals scavenging. In particular, AC has been determined using 3 standardised methods (DPPH, ABTS, ORAC) and a recently proposed electrochemical method, which measures the scavenging activity of antioxidants towards OH radicals generated both by hydrogen peroxide photolysis and the Fenton reaction. The results obtained from chemical composition and antioxidant capacity assays confirm the high nutritional and commercial value of goji berries and highlight that the three brands do not exhibit significant differences.

Simultaneous determination of umbelliferone and scopoletin in Tibetan medicine Saussurea laniceps and traditional Chinese medicine Radix angelicae pubescentis using excitation-emission matrix fluorescence coupled with second-order calibration method

A chemometrics-assisted excitation-emission matrix (EEM) fluorescence method is presented for simultaneous determination of umbelliferone and scopoletin in Tibetan medicine Saussurea laniceps (SL) and traditional Chinese medicine Radix angelicae pubescentis (RAP). Using the strategy of combining EEM fluorescence data with second-order calibration method based on the alternating trilinear decomposition (ATLD) algorithm, the simultaneous quantification of umbelliferone and scopoletin in the two different complex systems was achieved successfully, even in the presence of potential interferents. The pretreatment is simple due to the "second-order advantage" and the use of "mathematical separation" instead of awkward "physical or chemical separation". Satisfactory results have been achieved with the limits of detection (LODs) of umbelliferone and scopoletin being 0.06ngmL(-1) and 0.16ngmL(-1), respectively. The average spike recoveries of umbelliferone and scopoletin are 98.8±4.3% and 102.5±3.3%, respectively. Besides, HPLC-DAD method was used to further validate the presented strategy, and t-test indicates that prediction results of the two methods have no significant differences. Satisfactory experimental results imply that our method is fast, low-cost and sensitive when compared with HPLC-DAD method.

Activation of β1-adrenoceptor triggers oxidative stress mediated myocardial membrane destabilization in isoproterenol induced myocardial infarcted rats: 7-hydroxycoumarin and its counter action

Activation of β1-adrenoceptor stimulates myocardial membrane destabilization in isoproterenol induced rats. Male albino Wistar rats were pre and co-treated with 7-hydroxycoumarin (16mg/kg body weight) daily for 8 days. Myocardial infarction was induced into rats by the subcutaneous administration of isoproterenol (100mg/kg body weight) at an interval of 24h daily for a period of two days (7th and 8th day). The levels/activities of serum cardiac troponin-T, lactate dehydrogenase and the concentrations of heart lipid peroxidation products were significantly increased and the antioxidant status was significantly decreased in isoproterenol induced rats. Furthermore, the activity of sodium/potassium-dependent adenosine triphosphatase was significantly decreased and the activities of calcium and magnesium-dependent adenosine triphosphatases were significantly increased in the heart of isoproterenol induced myocardial infarcted rats. Isoproterenol induced rats also revealed increased concentrations of sodium and calcium and decreased concentrations of potassium in the heart. 7-hydroxycoumarin pre- and co-treatment showed considerable impact on all biochemical parameters assessed. Also, 7-HC greatly reduced the infarct size of the myocardium. The in vitro study confirmed its potent free radical scavenging activity. Thus, the present study revealed that 7-HC attenuates myocardial membrane destabilization by reinstating the activities/levels of adenosine triphosphatases and minerals in isoproterenol induced rats by inhibiting oxidative stress. These effects are attributed to the membrane stabilizing and free radical scavenging properties of 7-hydroxycoumarin.

Recent trends and advances in food chemistry and analysis: research highlights from the IX Italian Congress of Food Chemistry

The IX Italian Congress of Food Chemistry (ChimAlSi_2012) contributed 12 lectures, 66 conferences, and 290 posters to the wealth of food knowledge; these were presented in four sessions: food safety, analytical techniques, bioactive compounds, and nutraceuticals. Emerging topics were discussed in two workshops dealing with food contaminants, and food and health. It has been an excellent forum for passionate exchange of recent results obtained in traditional and emerging fields of food chemistry. The symposium allowed coverage of the broad diversity of food-related topics, comprising food contaminants and food quality and the application of analytical approaches, such as sensorial, physical, chemical, spectroscopic, hyphenated mass spectrometric, biological and chemometric techniques, as well as nutrition and health aspects.