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1.
EFSA J ; 22(2): e8563, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38322232

RESUMEN

Quillaia extract (E 999) was re-evaluated in 2019 by the EFSA Panel on Food Additives and Flavourings (FAF). EFSA derived an acceptable daily intake (ADI) of 3 mg saponins/kg bw per day for E 999. Following a European Commission call for data to submit data to fill the data gaps, the present follow-up opinion assesses data provided by interested business operators (IBOs) to support an amendment of the EU specifications for E 999. Additionally, this opinion deals with the assessment of the proposed extension of use for E 999 in food supplements supplied in a solid and liquid form, excluding food supplements for infants and young children and, as a carrier in botanical nutrients. The Panel concluded that the proposed extension of use, if authorised, could result in an exceedance of the ADI at the maximum of the ranges of the mean for children, adolescents and the elderly, and for all populations at the 95th percentile. An additional proposed extension of use for E 999 to be used as a carrier for glazing agents on entire fresh fruits and vegetables has been received. Since no information on the proposed use levels of E 999 on a saponins content basis has been provided by this applicant, the Panel was not able to evaluate the safety of this extension of use. Considering the technical data submitted, the Panel recommended some modifications of the existing EU specifications for E 999, mainly to lower the limits for lead, mercury and arsenic and to include a maximum limit for cadmium and for calcium oxalate. The Panel also recommended that the limits would be expressed on a saponins basis. The Panel proposed to revise the definition of E 999 to better describe the composition in a qualitative way.

2.
Int J Food Sci Nutr ; 72(6): 757-766, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33386060

RESUMEN

The aim of this research work was to study the chemical characterisation, antioxidant and cytotoxic activity of ethanolic extracts of four commercial algae species Arame, Kombu, Hijiki and Wakame. The highest scavenging activity has been observed in Arame extract. Antioxidant potential of all extracts was in correlation with total phenol content (Arame extract: 319.15 ± 0.56 mg GAE/g d.w) and it was not in correlation with total carotenoids content (Wakame: 75.15 ± 0.20 mg/g). Polyphenols were quantified using LC-MS/MS technique. Baicalein and amentoflavone were identified in higher amount in relation to other phenols. Intracellular antioxidant activity and cytotoxicity of algae extracts were evaluated on the human prostate cancer cell line PC3. Although presented biomolecules in the extracts have demonstrated in vitro antioxidant activity, they did not show a significant effect on PC3 cells. However, this study opens up broad perspective for the further comprehensive investigation of these, commercial, seaweed's biopotential.


Asunto(s)
Antioxidantes , Extractos Vegetales , Algas Marinas , Antioxidantes/farmacología , Línea Celular Tumoral , Cromatografía Liquida , Humanos , Fenoles/análisis , Fenoles/farmacología , Extractos Vegetales/farmacología , Espectrometría de Masas en Tándem
3.
EFSA J ; 18(6): e06152, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32874328

RESUMEN

The Panel on Food Additives and Flavourings (FAF) provided a scientific opinion re-evaluating the safety of Sodium aluminium silicate (E 554) and potassium aluminium silicate (E 555) as food additives. The Scientific Committee for Food (SCF) assigned these food additives together with other aluminium-containing food additives a provisional tolerable weekly intake (PTWI) of 7 mg aluminium/kg body weight (bw). In 2008, EFSA established a tolerable weekly intake (TWI) of 1 mg aluminium/kg bw per week. Sodium aluminium silicate was shown in rats to be absorbed to a limited extent at 0.12 ± 0.011%. The Panel considered that potassium aluminium silicate would be absorbed and become systemically available similarly to sodium aluminium silicate. No information on the physicochemical characterisation of sodium aluminium silicate and potassium aluminium silicate when used as food additives has been submitted and only very limited toxicological data were available for sodium aluminium silicate. Exposure to E 554 was calculated based on the reported use levels in food supplements. Exposure to aluminium from this use of E 554 was calculated to exceed the TWI for aluminium. Based on the data provided by interested business operators, the Panel considered that E 555 is not being used as a carrier, but as an inseparable component of 'potassium aluminium silicate-based pearlescent pigments'. The Panel calculated the regulatory maximum exposure to E 555 as a carrier for titanium dioxide (E 171) and iron oxides and hydroxides (E 172). Exposure to aluminium from this single use at the maximum permitted level could theoretically far exceed the TWI. Considering that only very limited toxicological data and insufficient information on the physicochemical characterisation of both food additives were available, the Panel concluded that the safety of sodium aluminium silicate (E 554) and potassium aluminium silicate (E 555) could not be assessed.

4.
Food Chem Toxicol ; 123: 298-313, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30291944

RESUMEN

Coffee is a drink prepared from roasted coffee beans and is lauded for its aroma and flavour. It is the third most popular beverage in the world. This beverage is known by its stimulant effect associated with the presence of methylxanthines. Caffeine, a purine-like molecule (1,3,7 trymetylxantine), is the most important bioactive compound in coffee, among others such as chlorogenic acid (CGA), diterpenes, and trigonelline. CGA is a phenolic acid with biological properties as antioxidant, anti-inflammatory, neuroprotector, hypolipidemic, and hypoglicemic. Purinergic system plays a key role inneuromodulation and homeostasis. Extracellular ATP, other nucleotides and adenosine are signalling molecules that act through their specific receptors, namely purinoceptors, P1 for nucleosides and P2 for nucleotides. They regulate many pathological processes, since adenosine, for instance, can limit the damage caused by ATP in the excitotoxicity from the neuronal cells. The primary purpose of this review is to discuss the effects of coffee, caffeine, and CGA on the purinergic system. This review focuses on the relationship/interplay between coffee, caffeine, CGA, and adenosine, and their effects on ectonucleotidases activities as well as on the modulation of P1 and P2 receptors from central nervous system and also in peripheral tissue.


Asunto(s)
Cafeína/metabolismo , Ácido Clorogénico/metabolismo , Extractos Vegetales/metabolismo , Purinas/metabolismo , Animales , Cafeína/química , Ácido Clorogénico/química , Coffea/química , Café/química , Café/metabolismo , Humanos , Extractos Vegetales/química , Receptores Purinérgicos P1/genética , Receptores Purinérgicos P1/metabolismo , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2/metabolismo , Transducción de Señal
5.
J Med Food ; 20(2): 124-130, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28098506

RESUMEN

The deposition of amyloid protein as senile plaques is the major signature of Alzheimer's disease (AD). It is produced by the sequential cleavage of the amyloid precursor protein by secretases. Moreover, peppers are noted for their antiaging and cognitive enhancing properties. Thus, in this study, the effects of polyphenol-rich extracts from bell pepper on amyloid production and aggregation in vitro were investigated. Bell pepper (ripe and unripe) was extracted with methanol-1 N HCl (1:1 v/v). Thereafter, the inhibitory potentials of the extracts on ß-secretase and ß-amyloid1-40 aggregation were determined. Phenolic composition of the pepper fruits was further determined by HPLC-DAD (high performance liquid chromatography-diode array detector). There was a dose-dependent inhibition of ß-secretase by the pepper fruits with the ripe fruits (2.17 ± 0.17 µg/L) showing a significantly (P < .05) higher inhibitory effect than the unripe (3.44 ± 0.11 µg/L). Furthermore, Thioflavin-T and transmission electron microscopy analyses revealed that phenolic extracts from pepper fruits (1 and 10 µg/L) could counteract the initial aggregation of Aß1-40, as well as prevent further aggregation preformed fibrils. These inhibitory activities could be attributed to the predominant presence of phenolic constituents in the pepper fruits. It is possible to conclude that bell pepper could be a possible dietary intervention into the management of AD.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Péptidos beta-Amiloides/química , Capsicum/química , Inhibidores Enzimáticos/química , Fragmentos de Péptidos/química , Extractos Vegetales/química , Enfermedad de Alzheimer/metabolismo , Secretasas de la Proteína Precursora del Amiloide/química , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Péptidos beta-Amiloides/metabolismo , Humanos , Cinética , Fragmentos de Péptidos/metabolismo , Agregado de Proteínas
6.
J Nutr Biochem ; 38: 145-153, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27736734

RESUMEN

We evaluated the effect of chlorogenic acid (CGA), caffeine (CA) and coffee (CF) on components of the purinergic system from the cerebral cortex and platelets of streptozotocin-induced diabetic rats. Animals were divided into eight groups: control animals treated with (I) water (WT), (II) CGA (5 mg/kg), (III) CA (15 mg/kg) and (IV) CF (0.5 g/kg), and diabetic animals treated with (V) WT, (VI) CGA (5 mg/kg), (VII) CA (15 mg/kg) and (VIII) CF (0.5 g/kg). Our results showed an increase (173%) in adenosine monophosphate (AMP) hydrolysis in the cerebral cortex of diabetic rats. In addition, CF treatment increased adenosine diphosphate (ADP) and AMP hydrolysis in group VIII synaptosomes. Platelets showed an increase in ectonucleotidase activity in group V, and all treatments reduced the increase in adenosine triphosphate and ADP hydrolysis. Furthermore, there was an increase in platelet aggregation of 72% in the diabetic rats, and CGA and CF treatment reduced platelet aggregation by nearly 60% when compared to diabetic rats. In this context, we can suggest that CGA and CF treatment should be considered a therapeutic and scientific target to be investigated in diseases associated with hyperglycemia.


Asunto(s)
Cafeína/uso terapéutico , Corteza Cerebral/metabolismo , Ácido Clorogénico/uso terapéutico , Diabetes Mellitus Experimental/dietoterapia , Neuropatías Diabéticas/prevención & control , Suplementos Dietéticos , Fármacos Neuroprotectores/uso terapéutico , 5'-Nucleotidasa/antagonistas & inhibidores , 5'-Nucleotidasa/genética , 5'-Nucleotidasa/metabolismo , Nucleótidos de Adenina/metabolismo , Animales , Plaquetas/enzimología , Plaquetas/metabolismo , Corteza Cerebral/enzimología , Café , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Proteínas Ligadas a GPI/antagonistas & inhibidores , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Regulación Enzimológica de la Expresión Génica , Hidrólisis , Masculino , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/enzimología , Neuronas/metabolismo , Neuroprotección , Agregación Plaquetaria , Purinérgicos/uso terapéutico , Ratas Wistar , Sinaptosomas/enzimología , Sinaptosomas/metabolismo
7.
Anticancer Agents Med Chem ; 16(11): 1385-1402, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27109021

RESUMEN

The control of cancer onset and progression is recognized to benefit from specific molecular targeting. MiRNAs are increasingly being implicated in prostate cancer, and the evidence suggests they are possible targets for molecular therapy and diagnosis. In cancer cells, growing attention has been dedicated to novel molecular mechanisms linking the epigenetic scenario to miRNA dysregulation. Currently, the rising evidence shows that nutritional and natural agents, the so-called nutraceuticals, could modulate miRNAs expression, and, as a consequence, might influence cellular responses in health or diseases conditions, including cancer. Among dietary components, plant-derived polyphenols are receiving wide interest, either for their anti-aging and anti-oxidant properties, or for their more general "cell-protective" effects. Above all, their role in preventing the occurrence/recurrence of cancer and, in particular, their potentiality in nutritional intervention for modulating the functions of miRNAs and the epigenetic mechanisms, is still under active debate. This review is focused on the more recent highlights of the impact of miRNAs dysregulation on the onset and progression of prostate cancer, their interplay with epigenetic control and their modulation by natural agents.


Asunto(s)
Suplementos Dietéticos , Epigénesis Genética/genética , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de la Próstata/dietoterapia , Neoplasias de la Próstata/genética , Animales , Humanos , Masculino , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/prevención & control
8.
J Basic Clin Physiol Pharmacol ; 26(5): 471-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26030791

RESUMEN

BACKGROUND: Citrus peels are consumed in the form of infusions, candy or wine, based on their well-documented nutritional and medicinal properties. This study sought to investigate the effect of some citrus peels' [grapefruit (Citrus paradisii), orange (Citrus sinensis) and shaddock (Citrus maxima)] extracts on matrix metalloproteinase (MMP) and proteasome activities in primary human colonic tumor (Caco-2) and the metastatic cell lines (LoVo and LoVo/ADR) in a bid to explain the possible mechanism by which the peels could manage/prevent colon cancer. METHODS: The inhibition of MMP and proteasome activities in the cells by the peel extracts, as well as the identification of phenolic compounds using high-performance liquid chromatography with diode-array detection (HPLC-DAD), was determined. RESULTS: Orange peel extracts had the strongest inhibition of MMP in Caco-2 and LoVo cells, while shaddock had the least. Shaddock peel extracts also had the least MMP inhibition in LoVo/ADR lysates. Grapefruit had the least proteasome inhibition in Caco-2 and LoVo lysates, while there was no significant (p>0.05) difference in the proteasome inhibition of the peel extracts in LoVo/ADR lysates. The extracts inhibited proteasome activity in extract-treated cells, and HPLC fingerprinting of the extracts revealed the presence of some phenolic compounds such as quercetin, caffeic acid, kaempferol, catechin and naringin. CONCLUSIONS: The inhibition of MMP and proteasome activities in colon cancer cell lines suggests the potential use of citrus peels as functional food in the management and/or prevention of colon cancer.


Asunto(s)
Citrus/química , Neoplasias del Colon/tratamiento farmacológico , Frutas/química , Metaloproteasas/antagonistas & inhibidores , Extractos Vegetales/farmacología , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Células CACO-2 , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Humanos , Fenoles/química , Fenoles/farmacología , Extractos Vegetales/química
9.
Mol Cell Biochem ; 388(1-2): 277-86, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24370728

RESUMEN

Diabetes mellitus (DM) is associated with brain alterations that may contribute to cognitive dysfunctions. Chlorogenic acid (CGA) and caffeine (CA), abundant in coffee (CF), are natural compounds that have showed important actions in the brain. The present study aimed to evaluate the effect of CGA, CA, and CF on acetylcholinesterase (AChE), Na(+), K(+)-ATPase, aminolevulinate dehydratase (δ-ALA-D) activities and TBARS levels from cerebral cortex, as well as memory and anxiety in streptozotocin-induced diabetic rats. Animals were divided into eight groups (n = 5-10): control; control/CGA 5 mg/kg; control/CA 15 mg/kg; control/CF 0.5 g/kg; diabetic; diabetic/CGA 5 mg/kg; diabetic/CA 15 mg/kg; and diabetic/CF 0.5 g/kg. Our results demonstrated an increase in AChE activity and TBARS levels in cerebral cortex, while δ-ALA-D and Na(+), K(+)-ATPase activities were decreased in the diabetic rats when compared to control water group. Furthermore, a memory deficit and an increase in anxiety in diabetic rats were observed. The treatment with CGA and CA prevented the increase in AChE activity in diabetic rats when compared to the diabetic water group. CGA, CA, and CF intake partially prevented cerebral δ-ALA-D and Na(+), K(+)-ATPase activity decrease due to diabetes. Moreover, CGA prevented diabetes-induced TBARS production, improved memory, and decreased anxiety. In conclusion, among the compounds studied CGA proved to be a compound which acts better in the prevention of brain disorders promoted by DM.


Asunto(s)
Conducta Animal/efectos de los fármacos , Cafeína/farmacología , Ácido Clorogénico/farmacología , Café , Diabetes Mellitus Experimental/tratamiento farmacológico , Acetilcolinesterasa/biosíntesis , Animales , Ansiedad/tratamiento farmacológico , Peso Corporal/efectos de los fármacos , Corteza Cerebral/metabolismo , Masculino , Memoria/efectos de los fármacos , Trastornos de la Memoria/tratamiento farmacológico , Porfobilinógeno Sintasa/biosíntesis , Ratas , Ratas Wistar , ATPasa Intercambiadora de Sodio-Potasio/biosíntesis , Estreptozocina , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
10.
Food Chem ; 134(4): 1878-84, 2012 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23442633

RESUMEN

Berry anthocyanins have pronounced health effects, even though they have a low bioavailability. The common mechanism underlying health protection is believed to relate to antioxidant activity. Berry extracts, chemically characterised for their phenolic content, were prepared from bilberries (Vaccinium myrtillusL.) and blueberries (Vaccinium corymbosumL.); the bilberry extract was further purified to obtain the anthocyanin fraction. The antioxidant activity of each extract was examined at the cellular level. For this purpose a specific assay, known as cellular antioxidant activity assay (CAA), was implemented in different cell lines: human colon cancer (Caco-2), human hepatocarcinoma (HepG2), human endothelial (EA.hy926) and rat vascular smooth muscle (A7r5). Here we show for the first time that anthocyanins had intracellular antioxidant activity if applied at very low concentrations (<1 µg/l; nM range), thereby providing a long-sought rationale for their health protecting effects in spite of their unfavorable pharmacokinetic properties.


Asunto(s)
Antocianinas/química , Antioxidantes/química , Arándanos Azules (Planta)/química , Extractos Vegetales/química , Vaccinium myrtillus/química , Animales , Antocianinas/farmacología , Antioxidantes/farmacología , Línea Celular , Cromatografía Líquida de Alta Presión , Humanos , Espectrometría de Masas , Extractos Vegetales/farmacología , Ratas
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