Phenolics in cereals, fruits and vegetables: Occurrence, extraction and analysis

In vitro Antioxidant Potentials of Cyperus rotundus L. Rhizome Extracts and Their Phytochemical Analysis

Background:

Cyperus rotundus L. (family Cyperaceae), native to India, is a multivalent medicinal plant widely used in conventional medicine. The research reports on bioactive components from C. rotundus L. are scanty.

Objective:

The objective of the study was to optimize the best solvent system and bioprospect the possible phytochemicals in C. rotundus L. rhizome (CRR).

Materials and Methods:

The phytochemicals were extracted from the rhizomes of C. rotundus L. by successive Soxhlet technique with solvents of increasing polarity. The resultant extracts were analyzed for their total flavonoid content (TFC), total phenolic content (TPC), total proanthocyanidin content (TPAC), in vitro antioxidant potential, and inhibition of lipid peroxidation. The 70% acetone extract of CRR was analyzed using gas chromatography–mass spectrometry (GC-MS) for probable phytochemicals.

Results and Discussion:

The TPC, TFC, and TPAC estimates ranged from 0.036 ± 0.002 to 118.924 ± 5.946 μg/mg extract, 7.196 ± 0.359 to 200.654 ± 10.032 μg/mg extract, and 13.115 ± 0.656 to 45.901 ± 2.295 μg/mg extract, respectively. The quantities of TPC, TFC, and TPAC were found to be the highest in 70% acetone extract. The 70% acetone and 70% methanol extracts revealed best radical scavenging effect. GC-MS analysis of CRR extract revealed the presence of a novel compound 1 (2)-acetyl-3 (5)-styryl-5 (3)-methylthiopyrazole.

Conclusion:

The study indicated that 70% acetone and 70% methanol extracts of CRRs can be a potential source of antioxidants.

SUMMARY

The studies suggest 70% methanol and acetone as the suitable solvents for the extraction of phytochemicals

Novel compound 1(2)-Acetyl-3(5)-styryl-5(3)-methylthiopyrazole was detected in 70% acetone extract.

Abbreviations used: ACRE: Acetone C. rotundus L. rhizome extract; AlCl₃: Aluminum chloride; AQRE: Aqueous C. rotundus L. rhizome extract; CE: Catechin Equivalent; CHRE: Chloroform C. rotundus L. rhizome extract; CRR: C. rotundus L. rhizome; DPPH: 2,2 diphenyl-1-picrylhydrazyl; ETRE: Ethanolic C. rotundus L. rhizome extract; EARE: Ethyl acetate C. rotundus L. rhizome extract; FRP: Ferric reducing power; GAE: Gallic acid equivalent; GC-MS: Gas chromatography-mass spectrometry; HERE: Hexane C. rotundus L. rhizome extract; MERE: Methanolic C. rotundus L. rhizome extract; PERE: Petroleum ether C. rotundus L. rhizome extract; QE: Quercetin equivalent; RNS: Reactive nitrogen species; ROS: Reactive oxygen species; TFC: Total flavonoid content; TPC: Total phenolic content; TPAC: Total proanthocyanidin content.

Antioxidant activity and Hypolipidemic effect of Ficus carica leaf and twig extracts in Triton WR-1339-induced hyperlipidemic mice

BACKGROUND/AIM: The hypolipidemic potential of both leaf and twig extracts of Ficus carica on experimental hyperlipidaemia induced by Triton WR-1339, in Swiss albino mice was investigated. In addition, the phenolic, flavonoid and anthocyanin contents of these extracts and their antioxidant activities were determined. These properties may have a synergistic effect on hyperlipidaemia. MATERIALS AND METHODS: Leaf and twig samples of F. carica were harvested and collected. The study of antioxidant activity of phenolic compounds was determined by the radical DPPH*, ABTS*+ and FRAP assays. The experimental design was carried out using acute oral toxicity study and Triton model hyperlipidaemia on Swiss albino adult male mice. The animals were observed continuously during the 14 days of the study for any physical signs of toxicity. On the 15th day, the animals were sacrificed by decapitation under anesthesia and the organs were observed for macroscopic pathological lesions. Hyperlipidaemia was induced in the mice by a single intravenous (iv) injection of Triton WR 1339 (300 mg/kg body weight), and the antihyperlipidemic effect of each extract, studied at 150 and 300 mg, was tested by gavage. After 24 hours of administration, serum from blood samples was used to estimate the various parameters of the lipid profile namely TC, TG, LDL and HDL. RESULTS: The results of the phenolic and flavonoid compounds of Ficus carica leaves and twigs varied from 12.84 to 19.78 mg gallic acid equivalents (GAE) and 5.02 to 9.72 mg EQ/g dry matter, respectively. The scavenging activity (IC50) against the radical DPPH* and ABTS*+ varied from 346.2 to 461.38 μg/mL and 288.3 to 369.01 μg/mL for twigs and leaves respectively, and from 50.82 to 54.2 μg/mL for FRAP assay. The acute toxicity study showed no mortality and clinical signs of toxicity in the tested doses. The LD50 value of extracts of twigs and leaves of Ficus carica is greater than 5000 mg/kg. The results revealed that the administration of Ficus carica (FC) leaf and twig extracts resulted in a significant (p < 0.05) decline in levels of serum triglycerides, total cholesterol, LDL-c, and VLDL-c, while the serum high-density lipoprotein cholesterol was significantly increased. The decrease rate of the lipid parameters differs significantly (p < 0.05) from the leaf and twig extracts and depends also on the administered dose. CONCLUSION: Ficus carica leaf and twig extracts may contain compounds able to lower plasma lipid concentrations, could contribute significantly to the total antioxidant properties and be beneficial in the treatment of hyperlipidaemia.

Optimization and validation of reverse phase HPLC method for qualitative and quantitative assessment of polyphenols in seaweed

A simple reverse phase-high performance liquid chromatography (RP-HPLC) coupled to a diode array detector (DAD) and negative ion electrospray mass spectrometer (ESI-MS) method was developed for simultaneous identification and quantification of phenolic antioxidants in seaweed. The proposed method was validated in terms of linearity, limits of detection (LOD), limits of quantification (LOQ), recovery and intermediate precision. The calibration curves were linear with correlation coefficient ranging from 0.9909 to 0.9997 while the values of LOD (0.26-0.82mg/L), LOQ (0.77-2.50mg/L), recovery (≥97.2%) and precision in terms of retention time (%RSD ≤2.27) and peak area (% RSD ≤5.11) were satisfactory. Brown seaweed Himanthalia elongata used in this study was extracted with 60% methanol and the crude extract was cleaned with SPE (Solid Phase Extraction) cartridge. HPLC-DAD-MS/MS analysis of the SPE fraction allowed the identification of 7 phenolic compounds comprising phlorotannins, hydroxybenzoic acid, hydroxycinnamic acid and flavonols subclasses of polyphenols. Quantitative analysis of these compounds revealed the presence of phloroglucinol (394.1±4.33μg/g), gallic acid (96.3±3.12μg/g), chlorogenic acid (38.8±1.94μg/g), caffeic acid (44.4±2.72μg/g), ferulic acid (17.6±0.85μg/g), myricetin (8.6±0.85μg/g) and quercetin (4.2±0.15μg/g), in the extract. The SPE fraction were tested for antioxidant capacity which were significantly (P <0.05) higher (EC50; 14.5±0.57mg/g) than the ascorbic acid (EC50; 35.8±0.59mg/g) and the crude extract (EC50; 46.3±0.48mg/g). The occurrence of all these phenolic antioxidant compounds in H. elongata extract suggested that the developed method is sensitive enough and reproducible and could be used for qualitative and quantitative assessment of polyphenols in seaweed.

Effects of quercitrin on bacterial translocation in a rat model of experimental colitis

BACKGROUND

This study aimed to analyze the effects of quercitrin, which has anti-inflammatory properties, on bacterial translocation in inflammatory bowel diseases by using an experimental colitis model.

METHODS

Forty male Wistar-Albino rats were used in the study. Rats were divided into 4 groups (control, colitis, treatment 1 and 2 groups). The rats in the control group were given normal drinking water. In the colitis group, colitis was induced by 5% DSS in drinking water. The control and colitis groups underwent operation on Day 7. In the 2 treatment groups, 5% DSS was added to drinking water for the first 7 days and the groups were treated with quercitrin at the doses of 1 and 5 mg/kg/day for the following 10 days. Treatment groups operated on Day 18. Blood samples were taken for blood culture and left colectomy was performed. The inflammation in the colon was macroscopically and microscopically evaluated and graded. Tissue samples were taken (liver, spleen and mesenteric lymph nodes (MLN)) for tissue culturing in order to assess bacterial translocation. Tissue myeloperoxidase (MPO), serum tumor necrosis factor-alpha (TNF-α) and plasma endotoxin levels were measured.

RESULTS

When the control and colitis groups were compared, observed that colitis was induced by DSS (p < 0.05). When the colitis and treatment groups were compared, it was found that quercitrin had a significant therapeutic effect (p < 0.05).

CONCLUSION

In the experimental colitis model established by using DSS, treatment with quercitrin resulted in a histopathological improvement and reduction in biochemical parameters, inflammation and in bacterial translocation (p < 0.05).

Natural polyphenols effects on protein aggregates in Alzheimer's and Parkinson's prion-like diseases

Alzheimer's and Parkinson's diseases are the most common neurodegenerative diseases. They are characterized by protein aggregates and so can be considered as prion-like disease. The major components of these deposits are amyloid peptide and tau for Alzheimer's disease, α-synuclein and synphilin-1 for Parkinson's disease. Drugs currently proposed to treat these pathologies do not prevent neurodegenerative processes and are mainly symptomatic therapies. Molecules inducing inhibition of aggregation or disaggregation of these proteins could have beneficial effects, especially if they have other beneficial effects for these diseases. Thus, several natural polyphenols, which have antioxidative, anti-inflammatory and neuroprotective properties, have been largely studied, for their effects on protein aggregates found in these diseases, notably in vitro. In this article, we propose to review the significant papers concerning the role of polyphenols on aggregation and disaggregation of amyloid peptide, tau, α-synuclein, synphilin-1, suggesting that these compounds could be useful in the treatments in Alzheimer's and Parkinson's diseases.

Emerging opportunities in exploring the nutritional/functional value of amaranth

Amaranthusspp. is a highly nutritive pseudocereal, rich in macronutrients and micronutrients, including vitamins and minerals.

Assessment of chemical and sensory quality of sugarcane alcoholic fermented beverage

This study aimed to verify the technological feasibility, chemical quality and sensory acceptance of alcoholic fermented beverage obtained from sugarcane juice. A completely randomized design was applied. Sugar and alcohol content, phenolic (HPLC-MS) and volatile (GS-MS) compounds, pH, density, dry matter and acidity of the fermented beverage of sugarcane were quantified, as well as the acceptance of the product was carried out. The complete fermentation of sugarcane lasted 7 days, and it was obtained an alcohol content of 8.0% v/v. Titrable acidity of the beverage was of 67.31 meq L-1, pH 4.03, soluble solids of 5 °Brix, reducing sugar of 0.07 g glucose 100 g-1, density of 0.991 g cm-3, reduced dry matter of 14.15 g L-1, sulfates lower than 0.7 g K2SO4 L-1. Various phenolic compounds, among which, gallic acid (10.97%), catechin (1.73%), chlorogenic acid (3.52%), caffeic acid (1.49%), vanillic acid (0.28%), p-coumaric acid (0.24%), ferulic acid (6.63%), m-coumaric acid (0.36%), and o-coumaric acid (0.04%). Amongst aromatic compounds, were found mainly esters with fruity aromas (ethyl ester hexanoic acid and ethyl ester octanoic acid). The sugarcane juice can be commercialized as an alternative wine, as it presented adequate features to an alcoholic fermented beverage and was sensory accepted by consumers.

Biological Activities of Camelina and Sophia Seeds Phenolics: Inhibition of LDL Oxidation, DNA Damage, and Pancreatic Lipase and α-Glucosidase Activities

The free, esterified and insoluble-bound phenolics of defatted meals of camelina and sophia seeds were extracted using an ultrasonic-assisted procedure and alkaline hydrolysis. The antioxidant activities of the extracts were evaluated using DPPH and hydroxyl radical scavenging assays as well as inhibition of bleaching of β-carotene in an oil-in-water system. Moreover, inhibition activity against pancreatic lipase, α-glucosidase, low density lipoprotein (LDL) oxidation and DNA damage induced by peroxyl and hydroxyl radicals were examined for all seed extracts using in vitro systems. The seed extracts of camelina and sophia not only showed significant antioxidant activity but also inhibited pancreatic lipase and α-glucosidase activities effectively. These enzymes in the digestive tract are associated with lipid and carbohydrate digestion, respectively, and control obesity and blood glucose level in the human body. The findings of this work may provide supporting information that camelina and sophia meals may inhibit human LDL oxidation and DNA nicking caused by free radicals and upon consumption may also exert anti-obesity and antidiabetic effects. However, further research is required to confirm these biological activities in vivo.

PRACTICAL APPLICATION

The seed phenolic extracts of camelina and sophia not only showed significant antioxidant activity but also effectively inhibited the activities of pancreatic lipase and α-glucosidase. Thus, camelina and sophia seed meals may serve as nutritional ingredients with bioactive phenolics that show in vitro antioxidant and biological effects. However, further research is required to confirm these health effects in vivo.

Photoprotective effects of cranberry juice and its various fractions against blue light-induced impairment in human retinal pigment epithelial cells

CONTEXT

Cranberry has numerous biological activities, including antioxidation, anticancer, cardioprotection, as well as treatment of urinary tract infection (UTI), attributed to abundant phenolic contents.

OBJECTIVE

The current study focused on the effect of cranberry juice (CJ) on blue light exposed human retinal pigment epithelial (ARPE-19) cells which mimic age-related macular degeneration (AMD).

MATERIALS AND METHODS

Preliminary phytochemical and HPLC analysis, as well as total antioxidant capacity and scavenging activity of cranberry ethyl acetate extract and different CJ fractions (condensed tannins containing fraction), were evaluated. In cell line model, ARPE-19 were irradiated with blue light at 450 nm wavelength for 10 h (mimic AMD) and treated with different fractions of CJ extract at different doses (5-50 μg/mL) by assessing the cell viability or proliferation rate using MTT assay (repairing efficacy).

RESULTS

Phytochemical and HPLC analysis reveals the presence of several phenolic compounds (flavonoids, proanthocyanidin, quercetin) in ethyl acetate extract and different fractions of CJ. However, the condensed tannin containing fraction of ethyl acetate extract of CJ displayed the greater (p < 0.05) scavenging activity especially at the dose of 1 mg/mL. Similarly, the condensed tannin containing fraction at 50 μg/mL presented better (p < 0.05) repairing ability (increased cell viability). Furthermore, the oligomeric condensed tannin containing fraction display the best (p < 0.05) repairing efficiency at 50 μg/mL.

DISCUSSION AND CONCLUSION

In conclusion, this study distinctly proved that condensed tannin containing fraction of CJ probably exhibits better free radicals scavenging activity and thereby effectively protected the ARPE-19 cells and thus, hampers the progress of AMD.

Effect of pre-treatment and extraction conditions on the antioxidant properties of persimmon (Diospyros kaki) leaves

Persimmon is a very delicious fruit and the leaves of this tree are used as a traditional drug. This study aimed to investigate the effects of drying method (hot air and freeze-drying), extraction temperature (80, 90 and 100 °C) and extraction time (10, 30, 60 and 120 min) and harvest stage (flowering and fruiting) on the antioxidant contents and antioxidant activity of persimmon leaves. The results showed that the highest antioxidants were obtained in both methods of drying. Also, 100 °C for 120 min of extraction gave the highest antioxidant contents, but with no significant difference compared to 90 °C for 60 min of extraction. Persimmon leaves collected during flowering stage had the maximum amount of antioxidants compared to the fruiting stage. Finally, it can be said that persimmon leaves harvested during flowering stage and treated by hot air drying with these extraction conditions (90 °C for 60 min) are richer in bioactive compounds.

Phytochemicals: Extraction, Isolation, and Identification of Bioactive Compounds from Plant Extracts

There are concerns about using synthetic phenolic antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) as food additives because of the reported negative effects on human health. Thus, a replacement of these synthetics by antioxidant extractions from various foods has been proposed. More than 8000 different phenolic compounds have been characterized; fruits and vegetables are the prime sources of natural antioxidants. In order to extract, measure, and identify bioactive compounds from a wide variety of fruits and vegetables, researchers use multiple techniques and methods. This review includes a brief description of a wide range of different assays. The antioxidant, antimicrobial, and anticancer properties of phenolic natural products from fruits and vegetables are also discussed.

Polyphenols in Raw and Cooked Cereals/Pseudocereals/Legume Pasta and Couscous

Pasta and couscous are popular foods manufactured (in their traditional form) from durum wheat semolina. In recent years, the consumers' quest for novel, functional, gluten-free, wholegrain foods has prompted the industry to manufacture new pasta and couscous products in which durum wheat has been partially or totally replaced by other vegetable flours. Besides dietary fibre, these raw materials might be an interesting source of phytochemicals. In this work, 16 commercial samples of pasta and four samples of couscous representative of the new products and made of refined and wholegrain flours of different species of cereals, pseudocereals and legumes were analysed for free, hydrolysable bound and total polyphenol content by means of the Folin-Ciocalteu procedure. Analyses were repeated on cooked samples to assess the quantity of polyphenols ingested by the consumers. The raw legume and pseudocereal products had a total polyphenol content higher than most cereal products (up to 1743.4 mg of Gallic Acid Equivalent (GAE) per 100 g dry weight). Wholegrain products had higher contents than refined products. The free fraction underwent up to 46% loss with cooking, probably because of solubility in water. The water absorption of pasta and couscous during cooking was in a ratio of 2:3, resulting in higher dilution of polyphenols in the cooked couscous.

Optimized preparation of anthocyanin-rich extract from black rice and its effects on in vitro digestibility

The procedure for obtaining anthocyanin-enriched extracts from black rice was optimized by response surface methodology, and the effects of the optimized extract on in vitro starch digestibility were investigated in a wheat flour gel model. The experimental results were well-described by a polynomial multiple regression model (R² = 0.8812, p = 0.0546) with regard to anthocyanin content in anthocyanin-enriched extracts from black rice. The optimal conditions for obtaining anthocyanin-enriched extracts from black rice were 50.78% ethanol and 1 N HCl (0.60 mL), yielding a predicted anthocyanin content of 624.27 mg cyanidin 3 glucoside extract. The optimized anthocyanin-enriched extract was a stronger inhibitor of α-glucosidase than acarbose. Furthermore, the predicted glycemic index values of gels prepared with the optimized extract were significantly lower than that of wheat flour gel. These results indicate that the optimized extract suppressed starch hydrolysis by inhibiting digestive enzymes.

Flow properties and chemical composition of carob (Ceratonia siliqua L.) flours as related to particle size and seed presence

Due to abundance in carbohydrates, dietary fibres and bioactive compounds, as well as for its outspread and low prices, carob (Ceratonia siliqua L.) flour has a great potential of use as a functional ingredient. The aim of this study was to analyse this potential by physical and chemical properties assessment of different particle sizes of carob flour with and without seeds. The influence of seed presence on physical and chemical properties of flour was also investigated. Seed presence in carob flour led to higher cohesivity and cake strength. It also affected the extraction efficiency of polyphenols, which was confirmed by the ranking of samples according to their procyanidin and tannins contents. With regard to the carbohydrate content, significant differences (P<0.05) between the contents of fructose and glucose was established in samples differing by the presence of carob seeds. Spearman rank order correlations revealed a significant difference (P<0.05) between physical and chemical properties of carob flours. These findings confirm the importance of understanding physical and chemical properties of carob flours in order to use them efficiently as a functional food ingredient.

Potential Use of Tuna (Thunnus albacares) by-product: Production of Antioxidant Peptides and Recovery of Unsaturated Fatty Acids from Tuna Head

Tuna by-products were subjected to enzymatic hydrolysis with Alcalase (enzyme to substrate ratio 1 : 200 w/w; 60 °C; pH 6.5, 120 min) rendering a tuna protein hydrolysate (TPH) with 9.24 % degree of hydrolysis (DH). The antioxidant capacity of TPH determined by the methods of ferric reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) were similar and 10 times lower than the result obtained by oxygen radical absorbance capacity (ORAC). The total amino acid profile indicated that 42.15 % are composed of hydrophobic amino acids and 7.7 % of aromatics, with leucine being found in the highest quantity (17.85 %). The fatty acid profile of the oil recovered by centrifugation of the TPH – as determined by a gas chromatograph – was characterized by a high percentage of polyunsaturated fatty acids (PUFAs) (39.06 %), mainly represented by the fatty acids ω3, docosahexaenoic acid (27.15 %) and eicosapentaenoic acid (6.05 %). The simultaneous recovery of unsaturated fatty acids and antioxidant peptides can add value to tuna by-products, assisting in the efficient management of fishing industry waste.

Chemical profiling of infusions and decoctions of Helichrysum italicum subsp. picardii by UHPLC-PDA-MS and in vitro biological activities comparatively with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis)

Several medicinal plants are currently used by the food industry as functional additives, for example botanical extracts in herbal drinks. Moreover, the scientific community has recently begun focusing on halophytes as sources of functional beverages. Helichrysum italicum subsp. picardii (everlasting) is an aromatic halophyte common in southern Europe frequently used as spice and in traditional medicine. In this context, this work explored for the first time H. italicum subsp. picardii as a potential source of innovative herbal beverages with potential health promoting properties. For that purpose, infusions and decoctions were prepared from roots, vegetative aerial-organs (stems and leaves) and flowers and evaluated for in vitro antioxidant and anti-diabetic activities. Samples were also assessed for toxicity in different mammalian cell lines and chemically characterized by spectrophotometric methods and ultra-high performance liquid chromatography-photodiode array-mass-spectrometry (UHPLC-PDA-MS). Results were expressed relating to 'a cup-of-tea' and compared with those obtained with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis). Tisanes from the everlasting's above-ground organs, particularly flowers, have high polyphenolic content and several phenolics were identified; the main compounds were chlorogenic and quinic acids, dicaffeoylquinic-acid isomers and gnaphaliin-A. The antioxidant activity of beverages from the everlasting's above-ground organs matched or surpassed that of green tea and rooibos. Its anti-diabetic activity was moderate and toxicity low. Overall, our results suggest that the everlasting is a potential source of innovative and functional herbal beverages.

Antioxidant Properties of Crude Extract, Partition Extract, and Fermented Medium of Dendrobium sabin Flower

Antioxidant properties of crude extract, partition extract, and fermented medium from Dendrobium sabin (DS) flower were investigated. The oven-dried DS flower was extracted using 100% methanol (w/v), 100% ethanol (w/v), and 100% water (w/v). The 100% methanolic crude extract showed the highest total phenolic content (40.33 ± mg GAE/g extract) and the best antioxidant properties as shown by DPPH, ABTS, and FRAP assays. A correlation relationship between antioxidant activity and total phenolic content showed that phenolic compounds were the dominant antioxidant components in this flower extract. The microbial fermentation on DS flower medium showed a potential in increasing the phenolic content and DPPH scavenging activity. The TPC of final fermented medium showed approximately 18% increment, while the DPPH of fermented medium increased significantly to approximately 80% at the end of the fermentation. Dendrobium sabin (DS) flower showed very good potential properties of antioxidant in crude extract and partition extract as well as better antioxidant activity in the flower fermented medium.

Physico-chemical, rheological and antioxidant properties of sweet chestnut (Castanea sativa Mill.) as affected by pan and microwave roasting

Sweet chestnut (Castanea sativa Mill.) belongs to the family Fagaceae and sub family Castaneoideae. Bioactive components such as tannins are present in sweet chestnut in high proportion giving astringent bitter taste and reducing their palatability. Roasting reduces the anti-nutritional factors in chestnut. This study was conducted to compare the effects of pan and microwave roasting on physicochemical, functional, rheological and antioxidant properties of sweet chestnut. Antioxidant activity was determined using DPPH inhibition activity, reducing power, and total phenolic content. Structural analysis was carried out using FT-IR analysis. Protein, fat, and ash contents displayed insignificant (P > 0.05) variations. "L" value decreased from 90.66 to 81.43, whereas, "a" and "b" values increased from 0.02 to 0.90 and 11.99 to 20.5, respectively, upon roasting. Significant (P < 0.05) increase in water absorption capacity (1.32-3.39 g/g), oil absorption capacity (1.22-1.63 g/g), and antioxidant properties was observed following roasting. Flour obtained from roasted chestnuts exhibited a significant decrease in light transmittance, foaming, and pasting properties. Higher gelatinization temperatures and lower enthalpies were reported in microwave and pan roasted chestnut flours. Roasting also reduced the viscoelastic behavior of native sweet chestnut and changed the transmittance of identical functional groups as revealed by FT-IR analysis.

Inhibitory mechanism of five natural flavonoids against murine norovirus

BACKGROUND

Human noroviruses (HuNoV), which are responsible for acute gastroenteritis, are becoming a serious public health concern worldwide. Since no effective antiviral drug or vaccine for HuNoV has been developed yet, some natural extracts and their active components have been investigated for their ability to inhibit noroviruses. However, their exact antiviral mechanisms have not been investigated.

PURPOSE

This study was performed to investigate the expression of interferon (IFN)-α, IFN-λ, tumor necrosis factor-α (TNF-α), Mx, and zinc finger CCCH type antiviral protein 1 (ZAP), 2'-5' oligo (A) synthetase (OAS), and inducible nitric oxide synthase (iNOS) in RAW 264.7 cells pre-treated with fisetin, daidzein, quercetin, epigallocatechin gallate (EGCG), and epicatechin gallate (ECG) that have anti-noroviral activity.

STUDY DESIGN

Based on the antiviral activity of the five flavonoids, recently reported by our group, the expression of antiviral factors such as IFN-α, IFN-λ, TNF-α, IL-1β, IL-6, Mx, ZAP, OAS, and iNOS was investigated in RAW 264.7 cells pre-treated with these flavonoids.

METHODS

Anti-noroviral effect was determined by performing a plaque assay on cells treated with the flavonoid. RAW 264.7 cells were treated with fisetin, daidzein, quercetin, EGCG, and ECG. Then, mRNA of IFN-α, IFN-λ, TNF-α, IL-1β, IL-6, Mx, ZAP, OAS, and iNOS were measured by real-time RT-PCR. IFN-α, TNF-α, IL-1β, and IL-6 proteins were measured by ELISA.

RESULTS

Pre-treatment with fisetin (50μM), fisetin (100μM), EGCG (100μM), quercetin (100μM), daidzein (50μM), and ECG (150μM) significantly reduced MNoV by 50.00±7.14 to 60.67±9.26%. The mRNA levels of IFN-α, IFN-λ, TNF-α, Mx, and ZAP were upregulated in RAW 264.7 cells pre-treated with fisetin, quercetin, and daidzein, but not in those pre-treated with EGCG or ECG. Regarding protein levels, IFN-α was significantly induced in cells pre-treated with fisetin, quercetin, and daidzein, whereas TNF-α was significantly induced only in cells pre-treated with daidzein.

CONCLUSION

Pre-treatment of RAW 264.7 cells with the five flavonoids inhibited MNoV by upregulating the expression of antiviral cytokines (IFN-α, IFN-λ, and TNF-α) and interferon-stimulating genes (Mx and ZAP).

Anthelmintic activity of Tunisian chamomile (Matricaria recutita L.) against Haemonchus contortus

The chemical treatment of gastrointestinal parasitic diseases has been undermined by increasing resistance and high toxicity. There is an urgent need to search for alternative natural sources for the treatment of such parasites. In this respect, the present study aims to quantify phenolic compounds of chamomile (Matricaria recutita L.) and to study their in vitro anti-oxidant and anthelmintic activities in solvents with increasing polarity. In vitro determination of anti-oxidant capacity was carried out using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation methods. In vitro anthelmintic activity was investigated on egg-hatching inhibition and loss of motility of adult worms of Haemonchus contortus from sheep. The results showed that methanolic and aqueous extracts contain more total polyphenols, total flavonoids and condensed tannins than chloroformic and hexanic extracts. ABTS and DPPH assays showed that methanolic extracts had the highest anti-oxidant potency (IC50 = 1.19 μg/ml and 1.18 μg/ml, respectively). In vitro anthelmintic activity showed that both methanolic (IC50 = 1.559 mg/ml) and aqueous (IC50 = 2.559 mg/ml) extracts had the greatest effect on egg hatching and motility of worms (100% after 8 h post exposure at 8 mg/ml). A significant and positive correlation between DPPH and ABTS tests was observed for all tested extracts. Therefore, total phenolic, total flavonoid and condensed tannin values were correlated with IC50 from both ABTS and DPPH, and with inhibition of egg hatching. To our knowledge, this report is the first of its kind to deal with in vitro anthelmintic activities of chamomile extracts.