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1.
Phytomedicine ; 91: 153699, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34419735

RESUMEN

BACKGROUND: Although a number of systematic reviews and meta-analyses of saffron (Crocus sativus L.) have been published, no study has comprehensively summarized the clinical evidence from meta-analyses, or assessed the reporting or methodological quality of these reviews. PURPOSE: The present meta-research study was designed to fill the gaps in knowledge to inform future studies and allow enhanced clinical decision-making on saffron. METHODS: The PubMed, Cochrane Library, Embase, and CNKI databases were systematically searched from inception to April 3 rd, 2021, for meta-analyses of clinical trials that assessed the efficacy and safety of saffron. PRISMA 2009 and AMSTAR-2 were employed to assess the reporting and methodological quality of meta-analyses identified in the search, respectively. The present study was registered on PROSPERO with registration number CRD42020220274. RESULTS: Nineteen eligible systematic reviews with meta-analyses published in English were identified from 235 records. These meta-analyses were published in 12 peer-reviewed journals from 2013 to 2021. The heterogeneous results indicated that saffron significantly reduced fasting blood glucose, waist circumference, diastolic blood pressure, concentrations of total cholesterol and low-density lipoprotein cholesterol, and improved symptoms of depression, cognitive function and sexual dysfunction compared with controls (mainly placebos). Common side effects of saffron consumption included nausea, dry mouth, poor appetite, and headache, but no serious adverse reactions were reported. Primary analysis and sensitivity analysis confirmed that the reporting and methodological quality of reviews included in the study were highly correlated (p < 0.001). The quality of meta-analyses of saffron requires improvement by including a structured abstract, a prospective protocol and registration, explanation of the study designs within each study that is reviewed, the searches, risk of bias assessment, literature selection, and reporting of funding sources. CONCLUSION: The available evidence indicates that saffron is a safe plant for administration as a medicine and can improve diverse clinical outcomes, but the scientific quality of the published systematic reviews needs to be improved. Moreover, the clinical effects of saffron need to be confirmed through high-quality randomized trials in multiple countries with large sample sizes.


Asunto(s)
Crocus , Preparaciones de Plantas/farmacología , Ensayos Clínicos como Asunto , Crocus/química , Humanos , Metaanálisis como Asunto , Preparaciones de Plantas/efectos adversos , Revisiones Sistemáticas como Asunto
2.
Metabol Open ; 11: 100111, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34312610

RESUMEN

AIM: To assess the potential role of saffron in downregulating inflammation and cytokine storm during COVID-19. MAIN FINDINGS: Three main compounds of saffron, i.e., crocetin esters, picrocrocin, and safranal, present strong antioxidant and anti-inflammatory action for several disease states (e.g., Alzheimer's, cancer, and depression) but have also been studied in COVID-19. In particular, based on our comprehensive review of both in vitro and in silico studies, saffron's essential oils and other constituents appear to have both immunomodulatory and anti-asthmatic actions; these actions can be particularly helpful to treat patients with respiratory symptoms due to COVID-19. Moreover, crocin appears to reduce the COVID-19-related cytokine cascade and downregulate angiotensin-converting enzyme 2 (ACE2) gene expression. Last, in silico studies suggest that saffron's astragalin and crocin could have inhibitory actions on SARS-CoV-2 protease and spike protein, respectively. CONCLUSION: Saffron represents a promising substance for toning down cytokine storm during COVID-19, as well as a potential preventive treatment for COVID-19. However, appropriate randomized clinical trials, especially those using biomarkers as surrogates to assess inflammatory status, should be designed in order to assess the clinical efficacy of saffron and allow its use as an adjunct treatment modality, particularly in resource-poor settings where access to drugs may be limited.

3.
J Agric Food Chem ; 67(17): 4746-4753, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30966749

RESUMEN

A green approach for the encapsulation of Mentha pulegium essential oil in commercial baker's yeast and its evaluation as a pesticide against the insect pest Myzus persicae are presented. Upon treating aqueous yeast cell dispersion with the essential oil, the formation of essential-oil-loaded microparticles of about 9 µm is observed, with a loading capacity ranging from 29 to 36%, depending upon the encapsulation conditions. The thermal properties of the microparticles were characterized using differential scanning calorimetry and thermogravimetric analysis, confirming the protection of the essential oil from the cells. Encapsulation prolonged the insecticidal activity of the essential oil by 3 days.


Asunto(s)
Composición de Medicamentos/métodos , Tecnología Química Verde/métodos , Insecticidas/química , Mentha pulegium/química , Aceites Volátiles/química , Extractos Vegetales/química , Levaduras/química , Animales , Áfidos/efectos de los fármacos , Áfidos/crecimiento & desarrollo , Insecticidas/farmacología , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología
4.
Parasitol Res ; 117(6): 1953-1964, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29717370

RESUMEN

In the current laboratory study, 14 essential oils (EOs) derived from 12 Lamiaceae plant species and their major components were screened for their larvicidal and repellent properties against Aedes albopictus, an invasive mosquito species of great medical importance. The results of toxicity bioassays revealed that the EOs from Thymus vulgaris, Ocimum basilicum, Origanum dictamnus, Origanum majorana, and Origanum vulgare, as well as their major components (terpenes), namely thymol, carvacrol, p-cymene, and γ-terpinene exerted the highest larvicidal effect. Essential oils from Mellisa officinalis, Origanum dictamus, Mentha spicata (chem. piperitenone epoxide), Origanum majorana, and Satureja thymbra were the most potent repellents, with the last two assigned as the best ones. Among the terpenes tested, piperitenone epoxide, carvacrol, thymol, and piperitenone provided the highest level of protection against Ae. albopictus adults. Chemical analysis revealed the presence of a high number of terpenes in the EOs, while in most cases, the biological action of the tested EOs and their major components was in consistency. The most effective EOs and terpenes that were identified through the current laboratory bioassays could be used as alternative agents to control larvae and repel adults of Ae. albopictus.


Asunto(s)
Aedes/efectos de los fármacos , Repelentes de Insectos/farmacología , Insecticidas/farmacología , Lamiaceae/química , Larva/efectos de los fármacos , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Animales , Monoterpenos Ciclohexánicos , Cimenos , Monoterpenos/farmacología , Ocimum basilicum/química , Origanum/química , Terpenos/farmacología , Timol/farmacología , Thymus (Planta)/química
5.
Phytochem Anal ; 29(5): 476-486, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29484754

RESUMEN

INTRODUCTION: The increasing interest on Crocus sativus L. over the last decades is caused by its potential employment as a source of biologically active molecules, endowed with antioxidant and nutraceutical properties. These molecules are present mainly in stigmas and tepals, these last generally considered as byproducts. OBJECTIVE: To characterise bioactive compounds in stigmas, stamens, and tepals of Crocus sativus L. for quality, cross-contamination of tissues or fraudulent addition, joining spectroscopic and chromatographic techniques. METHODOLOGY: Fourier transform infrared (FT-IR) and Raman spectroscopies were initially employed, being very rapid in response; volatiles were more appropriately investigated by gas chromatography with mass spectrometry (GC-MS), while finally nuclear magnetic resonance (NMR) and high-performance liquid chromatography with a diode array detector (HPLC-DAD) were adopted for a more thorough characterisation of secondary metabolites. NMR was also used to investigate the anthocyanins content in tepals upon acid extraction. RESULTS: The results obtained highlighted the drying method as the dominant factor affecting the content of volatile constituents and contributing to the quality of saffron, while only slight differences were observed in the most abundant metabolites of stigmas, as well as in the anthocyanin content of tepals. In particular, for the first time, delphinidin and petunidin were detected by NMR in this latter tissue. CONCLUSION: The integrated analytical methodology here proposed, allowed to achieve a deeper level of compositional and structural details of secondary metabolites in Crocus sativus L. flowers.


Asunto(s)
Crocus/química , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman
6.
Food Chem ; 221: 838-843, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-27979282

RESUMEN

The aim of this work was a comparison of the ISO 3632 (2011) method and an HPLC-DAD method for safranal quantity determination in saffron. Samples from different origins were analysed by UV-vis according to ISO 3632 (2011) and by HPLC-DAD. Both methods were compared, and there was no correlation between the safranal content obtained by UV-vis and HPLC-DAD. An over-estimation in the UV-vis experiment was observed, which was related to the cis-crocetin esters content, as well as other compounds. The results demonstrated that there was no relationship between ISO quality categories and safranal content using HPLC-DAD. Therefore, HPLC-DAD might be preferable to UV-vis for determining the safranal content and the classification of saffron for commercial purposes. In addition, HPLC-DAD was adequate for determining the three foremost parameters that define the quality of saffron (crocetin esters, picrocrocin and safranal); therefore, this approach could be included in the ISO 3632 method (2011).


Asunto(s)
Cromatografía Líquida de Alta Presión , Crocus/química , Ciclohexenos/análisis , Análisis de los Alimentos/métodos , Terpenos/análisis , Rayos Ultravioleta , Carotenoides/análisis , Ésteres/análisis , Calidad de los Alimentos , Glucósidos/análisis , Extractos Vegetales/química , Vitamina A/análogos & derivados , Compuestos Orgánicos Volátiles/análisis
7.
Food Chem ; 217: 418-424, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27664653

RESUMEN

Saffron, the dried red stigmas of Crocus sativus L., is considered as one of the most expensive spices worldwide, and as such, it is prone to adulteration. This study introduces an NMR-based approach to identify and determine the adulteration of saffron with Sudan I-IV dyes. A complete (1)H and (13)C resonance assignment for Sudan I-IV, achieved by two-dimensional homonuclear and heteronuclear NMR experiments, is reported for the first time. Specific different proton signals for the identification of each Sudan dye in adulterated saffron can be utilised for quantitative (1)H NMR (qHNMR), a well-established method for quantitative analysis. The quantification of Sudan III, as a paradigm, was performed in varying levels (0.14-7.1g/kg) by considering the NMR signal occurring at 8.064ppm. The high linearity, accuracy and rapidity of investigation enable high resolution (1)H NMR spectroscopy to be used for evaluation of saffron adulteration with Sudan dyes.


Asunto(s)
Compuestos Azo/análisis , Colorantes/análisis , Crocus , Contaminación de Medicamentos , Espectroscopía de Resonancia Magnética/métodos , Compuestos Azo/química , Colorantes/química , Crocus/química , Naftoles/análisis , Naftoles/química , Extractos Vegetales/análisis , Extractos Vegetales/química , Protones , Especias/análisis
8.
Talanta ; 162: 558-566, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27837871

RESUMEN

Saffron, the dried red stigmas of the plant Crocus sativus L., is well-known as one of the most important and expensive spices worldwide. It is thus highly susceptible to fraudulent practices that employ, among others, plant-derived adulterants. This study presents an application of diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and chemometric techniques for evaluating adulteration of saffron with six characteristic adulterants of plant origin, i.e. C. sativus stamens, calendula, safflower, turmeric, buddleja, and gardenia. The proposed method involved a three-step process for the detection of adulteration as well as for the identification and quantification of adulterants. Partial least squares discriminant analysis (PLS-DA) was applied to perform authentication of saffron based on mid-infrared fingerprints (4000-600cm-1), resulting in 99% correct classification of pure saffron and saffron adulterated at 5-20% (w/w) levels. Adulterant identification in positive samples was performed with high sensitivity and specificity by a six-class PLS-DA model, with spectroscopic data from the region 2000-600cm-1. Subsequently, partial least squares (PLS) regression models were built for the quantification of each adulterant. By using synergy interval PLS (siPLS) for variable selection, models with improved performance were developed, with detection limits ranging from 1.0% to 3.1% (w/w). The results obtained illustrate that this strategy based on DRIFTS has the potential to complement existing methodologies for the rapid and cost-effective assessment of typical saffron frauds.


Asunto(s)
Crocus/química , Contaminación de Alimentos/análisis , Plantas/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Especias/análisis , Análisis Discriminante , Contaminación de Alimentos/prevención & control , Análisis de los Mínimos Cuadrados , Plantas/clasificación , Reproducibilidad de los Resultados , Especificidad de la Especie
9.
Chem Biodivers ; 14(3)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27770481

RESUMEN

Essential oils from Greek Mentha species showed different chemical compositions for two populations of M. pulegium, characterized by piperitone and pulegone. Mentha spicata essential oil was characterized by endocyclic piperitenone epoxide, piperitone epoxide, and carvone. The bioactivities of these essential oils and their components have been tested against insect pests (Leptinotarsa decemlineata, Spodoptera littoralis and Myzus persicae), root-knot nematodes (Meloydogine javanica) and plants (Lactuca sativa, Lolium perenne, Solanum lycopersicum). The structure-activity relationships of these compounds have been studied including semi-synthetic endocyclic trans-carvone epoxide, exocyclic carvone epoxide, a new exocyclic piperitenone epoxide and trans-pulegone epoxide. Leptinotarsa decemlineata feeding was affected by piperitenone and piperitone epoxide. Spodoptera littoralis was affected by piperitone epoxide and pulegone. The strongest nematicidal agent was piperitenone epoxide, followed by piperitone epoxide, piperitenone and carvone. Germination of S. lycopersicum and L. perenne was significantly affected by piperitenone epoxide. This compound and carvone epoxide inhibited L. perenne root and leaf growth. Piperitenone epoxide also inhibited the root growth of S. lycopersicum. The presence of a C(1) epoxide resulted in strong antifeedant, nematicidal and phytotoxic compounds regardless of the C(4) substituent. New natural crop protectants could be developed through appropriate structural modifications in the p-menthane skeleton.


Asunto(s)
Mentha/química , Aceites Volátiles/química , Animales , Monoterpenos Ciclohexánicos , Compuestos Epoxi/química , Cromatografía de Gases y Espectrometría de Masas , Germinación/efectos de los fármacos , Solanum lycopersicum/efectos de los fármacos , Solanum lycopersicum/crecimiento & desarrollo , Mentha/metabolismo , Monoterpenos/análisis , Monoterpenos/química , Monoterpenos/farmacología , Aceites Volátiles/farmacología , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Spodoptera/efectos de los fármacos , Relación Estructura-Actividad
10.
Food Chem ; 173: 890-6, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25466103

RESUMEN

In the present work, a preliminary study for the detection of adulterated saffron and the identification of the adulterant used by means of (1)H NMR and chemometrics is reported. Authentic Greek saffron and four typical plant-derived materials utilised as bulking agents in saffron, i.e., Crocus sativus stamens, safflower, turmeric, and gardenia were investigated. A two-step approach, relied on the application of both OPLS-DA and O2PLS-DA models to the (1)H NMR data, was adopted to perform authentication and prediction of authentic and adulterated saffron. Taking into account the deficiency of established methodologies to detect saffron adulteration with plant adulterants, the method developed resulted reliable in assessing the type of adulteration and could be viable for dealing with extensive saffron frauds at a minimum level of 20% (w/w).


Asunto(s)
Crocus/química , Contaminación de Alimentos/análisis , Espectroscopía de Resonancia Magnética/métodos , Crocus/metabolismo , Flores/química , Flores/metabolismo
11.
Chemosphere ; 96: 74-80, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23938144

RESUMEN

Twenty acyclic monoterpenes with different functional groups (acetoxy, hydroxyl, carbonyl and carboxyl) bearing a variable number of carbon double bonds were assayed as repellent and larvicidal agents against the West Nile vector Culex pipiens. Seven of them were derivatives that were synthesized through either hydrogenation or oxidation procedures. All repellent compounds were tested at the dose of 1mgcm(-2) and only neral and geranial were also tested at a 4-fold lower dose (0.25mgcm(-2)). Repellency results revealed that geranial, neral, nerol, citronellol, geranyl acetate and three more derivatives dihydrolinalool (3), dihydrocitronellol (5) and dihydrocitronellyl acetate (6) resulted in no landings. Based on the LC50 values the derivative dihydrocitronellyl acetate (6) was the most active of all, resulting in an LC50 value of 17.9mgL(-1). Linalyl acetate, citronellyl acetate, neryl acetate, geranyl acetate, dihydrocitronellol (5), dihydrocitronellal (7), citronellol, dihydrolinalyl acetate (2), citronellic acid and tetrahydrolinalyl acetate (1) were also toxic with LC50 values ranging from 23 to 45mgL(-1). Factors modulating toxicity have been identified, thus providing information on structural requirements for the selected acyclic monoterpenes. The acetoxy group enhanced toxicity, without being significantly affected by the unsaturation degree. Within esters, reduction of the vinyl group appears to decrease potency. Presence of a hydroxyl or carbonyl group resulted in increased activity but only in correlation to saturation degree. Branched alcohols proved ineffective compared to the corresponding linear isomers. Finally, as it concerns acids, data do not allow generalizations or correlations to be made.


Asunto(s)
Culex/efectos de los fármacos , Insecticidas/toxicidad , Monoterpenos/toxicidad , Control de Mosquitos/métodos , Animales , Insecticidas/química , Monoterpenos/química , Pruebas de Toxicidad , Fiebre del Nilo Occidental/prevención & control
12.
Food Chem Toxicol ; 61: 152-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23712099

RESUMEN

In this survey, we analyzed the phenolic profile of six herbal infusions namely Cretan marjoram, pink savory, oregano, mountain tea, pennyroyal and chamomile by LCDAD-MS and by GC-MS. Further, we investigated their anticarcinogenic effect as to their ability to (a) scavenge free radicals (b) inhibit proliferation (c) decrease IL-8 levels and (d) regulate nuclear factor-kappa B in epithelial colon cancer (HT29) and prostate (PC3) cancer cells. All herbal infusions exhibited antiradical activity correlated positevely with total phenolic content. Further, infusions exhibited the potential to inhibit cell proliferation and to reduce IL-8 levels in HT29 colon and PC3 prostate cancer cells. The molecular target for chamomile in HT29 seemed to be the NF-κB, while for the other herbal infusions needs to be identified. This study is the first to show the potential chemopreventive activity of infusions prepared from the examined herbs.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antioxidantes/farmacología , Fenoles/análisis , Preparaciones de Plantas/análisis , Preparaciones de Plantas/farmacología , Antiinflamatorios no Esteroideos/química , Anticarcinógenos/farmacología , Antioxidantes/química , Línea Celular Tumoral/efectos de los fármacos , Manzanilla/química , Evaluación Preclínica de Medicamentos , Células HT29/efectos de los fármacos , Humanos , Interleucina-8/metabolismo , Masculino , Mentha pulegium/química , FN-kappa B/metabolismo , Origanum/química , Preparaciones de Plantas/química , Neoplasias de la Próstata/tratamiento farmacológico , Satureja/química , Sideritis/química
13.
J Agric Food Chem ; 61(13): 3235-41, 2013 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-23496773

RESUMEN

For the determination of rosmarinic acid (RA) directly in pulverized plant material, a method is developed using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) without any physicochemical pretreatment of samples. The RA content of 11 samples of eight different Lamiaceae herbs, as determined by high performance liquid chromatography (HPLC), varied between 86 ± 1 mg/g (in lemon balm) and 12.0 ± 0.8 mg/g (in hyssop) of dried plant material. The 11 samples and 50 other additional samples, which were prepared by mixing initial samples with KBr, were measured using DRIFTS. The second derivative of the spectral region 1344-806 cm(-1) was used and the corresponding data were analyzed using partial least squares (PLS) regression. The correlation between infrared spectral analysis and HPLC measurements shows that the DRIFTS method is sufficiently accurate, simple, and rapid. The RA content of the 11 Lamiaceae samples determined by DRIFTS ranged from 81 ± 4 mg/g (in lemon balm) to 12 ± 3 mg/g (in hyssop) of dried plant material.


Asunto(s)
Cinamatos/análisis , Depsidos/análisis , Lamiaceae/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Cromatografía Líquida de Alta Presión , Ácido Rosmarínico
14.
Artículo en Inglés | MEDLINE | ID: mdl-22795580

RESUMEN

The integral bioluminescence (BL) intensity of live Photobacterium phosphoreum cells (strain 1883 IBSO), sampled at the stationary growth stage (20 h), was monitored for further 300 h in the absence (control) and presence of (241)Am (an α-emitting radionuclide of a high specific activity) in the growth medium. The activity concentration of (241)Am was 2 kBq l(-1); [(241)Am]=6.5×10(-11) M. Parallel experiments were also performed with water-soluble humic substances (HS, 2.5 mg l(-1); containing over 70% potassium humate) added to the culture medium as a possible detoxifying agent. The BL spectra of all the bacterial samples were very similar (λ(max)=481±3 nm; FWHM=83±3 nm) showing that (241)Am (also with HS) influenced the bacterial BL system at stages prior to the formation of electronically excited states. The HS added per se virtually did not influence the integral BL intensity. In the presence of (241)Am, BL was initially activated but inhibited after 180 h, while the system (241)Am+HS showed an effective activation of BL up to 300 h which slowly decreased with time. Diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, applied to dry cell biomass sampled at the stationary growth phase, was used to control possible metabolic responses of the bacteria to the α-radioactivity stress (observed earlier for other bacteria under other stresses). The DRIFT spectra were all very similar showing a low content of intracellular poly-3-hydroxybutyrate (at the level of a few percent of dry biomass) and no or negligible spectroscopic changes in the presence of (241)Am and/or HS. This assumes the α-radioactivity effect to be transmitted by live cells mainly to the bacterial BL enzyme system, with negligible structural or compositional changes in cellular macrocomponents at the stationary growth phase.


Asunto(s)
Americio/farmacología , Sustancias Húmicas/análisis , Mediciones Luminiscentes/métodos , Photobacterium/efectos de los fármacos , Photobacterium/metabolismo , Biomasa , Viabilidad Microbiana/efectos de los fármacos , Photobacterium/citología , Espectroscopía Infrarroja por Transformada de Fourier , Factores de Tiempo
15.
Parasitol Res ; 111(6): 2253-63, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22903418

RESUMEN

Laboratory experiments were conducted to study the bioefficacy against Ae. albopictus of three Citrus essential oils, derived from peels of Citrus sinensis, Citrus limon, and Citrus paradise and of their components. Chiral gas chromatography analysis revealed the dominant occurrence of R-(+)-limonene and (-)-ß-pinene in all three essential oils while in the case of lemon oil γ-terpinene, neral, and geranial detected also among other components. The tested Citrus essential oils were toxic against mosquito larvae with LC(50) values ranging from 25.03 to 37.03 mg l(-1). Among citrus essential oils components tested, γ-terpinene was the most toxic (LC(50) = 20.21 mg l(-1)) followed by both enantiomeric forms of limonene (LC(50) = 35.99 and 34.89 mg l(-1), for R-(+)-limonene and S-(-)-limonene, respectively). The delayed toxic effects after exposure of larvae to sublethal (LC(50)) doses were also investigated for citrus essential oils and their major component R-(+)-limonene, indicating a significant reduction of pupal survival. In repellent bioassays, lemon essential oil, S-(-)-limonene, citral (mixture of neral\geranial) and (+)-ß-pinene were the most effective compared with other citrus essential oils and components against adult mosquitoes. Repellent bioassays also revealed that limonenes and ß-pinenes showed an isomer dependence repellent activity. Finally, according to enantiomeric distribution of limonene and α- and ß-pinene, the repellency of lemon essential oil is possibly attributed to the presence of citral.


Asunto(s)
Aedes/efectos de los fármacos , Citrus/química , Repelentes de Insectos/farmacología , Insecticidas/farmacología , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Animales , Bioensayo , Cromatografía de Gases , Vectores de Enfermedades , Repelentes de Insectos/química , Repelentes de Insectos/aislamiento & purificación , Insecticidas/química , Insecticidas/aislamiento & purificación , Isomerismo , Larva/efectos de los fármacos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Análisis de Supervivencia
16.
Phytochem Anal ; 23(1): 34-43, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21618307

RESUMEN

INTRODUCTION: Mentha pulegium L. (pennyroyal) is one of the four most commercially important Mentha species, even it is not a cultivated plant. It can be abundantly located in the Iberian Peninsula and North African countries. In Greece it grows in the wild and it is scattered all over the country. Pennyroyal is best known for its essential oil, with Spain and Morocco being the largest producers in the world. Mid-infrared spectroscopy has been applied to determine the origin of various samples. OBJECTIVES: In this work Fourier transform infrared spectroscopy (FT-IR) combined with canonical discriminant analysis has been applied to distinguish 70 Greek pennyroyal samples according to their collection areas. MATERIAL AND METHODS: Pennyroyal nonpolar organic extracts were prepared using ultrasound-assisted solvent extraction. The spectra of the extracts were recorded in the range of 4000-400 cm(-1) and the best discrimination was achieved in the spectral region 1720-1650 cm(-1) . RESULTS: Spectral features for the discrimination of pennyroyal samples among the different collection areas occur primarily in the carbonyl region and are correlated with the main volatile constituents of the extracts (menthone, isomenthone, pulegone, piperitone). All areas were easily differentiated by canonical discriminant analysis. The percentages of correct classification and validation were 94.3 and 90.0%, respectively. CONCLUSION: The combination of FT-IR spectroscopy and multivariate analysis provides a rapid and ambient method to discriminate pennyroyal samples in terms of geographical origin.


Asunto(s)
Mentha pulegium/química , Mentha pulegium/clasificación , Aceites Volátiles/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Cromatografía de Gases , Monoterpenos Ciclohexánicos , Análisis Discriminante , Geografía , Grecia , Mentol/análisis , Mentol/química , Mentol/aislamiento & purificación , Monoterpenos/análisis , Monoterpenos/química , Monoterpenos/aislamiento & purificación , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/análisis , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación
17.
Int J Food Microbiol ; 144(1): 202-7, 2010 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-20952082

RESUMEN

It was previously established that Lactobacillus fermentum ACA-DC 179, Lactobacillus plantarum ACA-DC 287 and Lactobacillus plantarum ACA-DC 2350 exhibit antimicrobial activity against Salmonella enterica serovar Typhimurium. In order to further investigate the killing effect of these microorganisms against Salmonella cells, we employed Fourier transform infrared spectroscopy (FT-IR). Salmonella cells were incubated with different concentrated lactobacilli supernatants and their FT-IR spectra were recorded. The second derivative transformation of the original spectra revealed changes in spectral regions corresponding to absorptions of major cellular constituents (e.g. cell wall, cell membrane, and proteins of the cell) among the Salmonella cells treated with the supernatants and those treated with the control samples. Principal component analysis of the second derivative transformed spectra showed that the yet unidentified antimicrobial compound(s) produced by the lactobacilli tested clearly interfered with the fatty acids of the cell membrane, as well as the polysaccharides of the cell wall in Salmonella cells, pointing towards a dual killing mode. Our study shed light for the first time in the anti-Salmonella activity of the particular Lactobacillus strains.


Asunto(s)
Antibacterianos/farmacología , Lactobacillus/química , Salmonella typhimurium/efectos de los fármacos , Espectroscopía Infrarroja por Transformada de Fourier , Pared Celular/efectos de los fármacos , Medios de Cultivo Condicionados/farmacología , Salmonella typhimurium/química
18.
J Agric Food Chem ; 58(10): 6011-7, 2010 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-20438079

RESUMEN

The feasibility of Raman spectroscopy for predicting the content of crocetin esters (crocins), and coloring strength was assessed. 114 samples from Greece, Iran, Italy and Spain were divided into two sets: a calibration set with 49 samples and a validation one with 65 samples. Calibration models for crocetin esters (r 0.97, RMSEC 0.92, RMSEP 0.97, RPD 3.46) and coloring strength (r 0.95, RMSEC 12.2, RMSEP 11.3, RPD 2.59) were built in the spectral region 1700-955 cm(-1) using partial least-squares (PLS) regression. The calibration models were validated using cross-validation, leaving one sample out (r 0.97, RMSECV 1.09 for crocetin esters and r 0.93, RMSECV 14.5 for coloring strength). The crocetin esters content as determined by liquid chromatography fluctuated between 18.8 and 31.7 mg/100 g saffron. The corresponding values, as calculated using the Raman method, fluctuated between 19.2 and 32.0 mg/100 g saffron. The coloring strength determined by the reference method ranged from 177.0 to 296.7 units, while with the Raman method the values were between 186.8 and 297.6 units. The results, as compared to the reference methods (liquid chromatography and UV-vis spectrophotometry), show that the proposed methodology gives data with acceptable accuracy. The proposed models can be used as a tool for rapid screening of quality in saffron samples.


Asunto(s)
Carotenoides/análisis , Crocus/química , Ésteres/análisis , Espectrometría Raman/métodos , Calibración , Cromatografía Líquida de Alta Presión , Color , Análisis de los Mínimos Cuadrados , Control de Calidad , Reproducibilidad de los Resultados , Vitamina A/análogos & derivados
19.
J Sci Food Agric ; 90(4): 719-25, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20355104

RESUMEN

BACKGROUND: The dehydration procedure is responsible for saffron sensorial properties: colour, taste and aroma. Changes in the compounds responsible for these characteristics have been studied when dehydration processes at high and low temperature are employed. However, the evolution of these changes at mild temperatures is not available in the current bibliography. In this paper the effect of different mild conditions (18-20 degrees C for 24 h, 40-50 degrees C for 75 min and 55 degrees C for 75 min) applied to 45 saffron samples with the same origin was investigated. RESULTS: Crocetin esters, the compounds responsible for saffron colour, increased their content with no significant differences from other processes when high temperatures (55 degrees C) were used, thus producing a noticeable increment in saffron colouring capability. Similar behaviour was obtained for picrocrocin, the compound responsible for saffron taste, with higher average content at the highest temperature (55 degrees C) but without significant differences with the inferior conditions (40-50 degrees C). However, more volatile compounds were generated, especially safranal,at higher temperatures, e.g. 55 degrees C, during the dehydration procedure. CONCLUSIONS: The results found support the idea for employing mild to high temperatures during the dehydration process of saffron.


Asunto(s)
Crocus/química , Desecación , Conservación de Alimentos/métodos , Especias/normas , Temperatura , Carotenoides/análisis , Color , Ciclohexenos/análisis , Ésteres/análisis , Flores/química , Glucósidos/análisis , Odorantes , Gusto , Terpenos/análisis , Vitamina A/análogos & derivados
20.
J Agric Food Chem ; 58(2): 1305-12, 2010 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-20028014

RESUMEN

In this paper, 345 saffron samples were analyzed from different countries to study their picrocrocin content using different analytical techniques. The E1cm 1% of 257 nm results from all samples are inflated in comparison by the high-performance liquid chromatography (HPLC) data, because of the interferences with the crocetin ester pool and especially with those with a lower trans/cis relation. A picrocrocin range update is proposed for International Organization for Standardization (ISO) 3632 normative because category III should be incremented up to 50 units, while category II should be incremented up to 60 units. More accurate data are achieved when the deltaEpic measurement is carried out. Consequently, improvements to the ISO method are suggested. Fourier transform (FT)-near-infrared spectrometry analysis has also been carried out, showing excellent results from the calibration with HPLC data. This spectrophotometric technique could be used by saffron enterprises to obtain quick and more accurate data for picrocrocin determination.


Asunto(s)
Crocus/química , Ciclohexenos/análisis , Glucósidos/análisis , Extractos Vegetales/análisis , Terpenos/análisis , Cromatografía Líquida de Alta Presión , Geografía
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