Comparison of molecularly imprinted polymers (MIP) and sol–gel molecularly imprinted silica (MIS) for fungicide in a hydro alcoholic solution

International audienceThe aim of this work was (i) to design the best molecularly imprinted silica (MIS) specific for iprodione, a fungicide polluting water, fruits, wine and (ii) to compare the performance of the optimal MIS with its analogue molecularly imprinted polymer (MIP), with the objective to obtained the highest imprinting factor possible. Iprodione was widely used in viticulture. It was recently banned by the European community because of its carcinogenic potential and its presence in or on foods.The binding capacity performance of these polymers was investigated using batch binding studies in hydro alcoholic solutions (10 and 50 %). Langmuir, Freundlich and Temkin models have been used to fit adsorption isotherms. The optimal MIS was obtained using APTMS as functional monomer, low solvent solventvolume and high cross linker quantity during its synthesis. Increasing the quantity of crosslinker and decreasing the solvent volume during the MIS synthesis enhanced the imprinting factor and the binding capacity.The optimal MIS had a higher imprinting factor but a lower binding capacity than the optimal MIP specific to iprodione. The imprinting factor of the optimal MIS was 135 times higher than the optimal MIP. Unlike MIP, MIS kept its molecular recognition nature even under extremely polar media such as the aqueous sample

Chemical Composition, Antioxidant, and Anti-Diabetic Activities of Scorzonera phaeopappa Boiss

International audienceWild edible plants have attracted increasing interest from researchers because of their richness in biologically active phytochemicals. These are found to be a potential remedy for oxidative-stress-mediated diseases such as diabetes mellitus. In this study, total phenol, total terpene, and total flavonoid content as well as antioxidant and antidiabetic activities of Scorzonera phaeopappa Boiss from Lebanon were determined. Using dichloromethane, dichloromethane ammonia, methanol, acetone, and ethanol, extracts were prepared from the edible leaves. The antioxidant activity and the antidiabetic activity were determined by 2,2-diphenyl-1-picrylhydrazyl scavenging, Fe2+-chelating and α-amylase/α-glucosidase inhibitory assays, respectively. Dichloromethane ammonia was found to have the highest extraction capacity on phenols (2.73 mg GAE /100 mg extract) and terpenes (232.42 mg LE/100 mg extract). Methanol was found to have the highest extraction capacity on total flavonoids (63.05 mg QE/100 mg extract). The methanol extract exhibited the highest DPPH scavenging activity (IC50 0.07 mg/mL) and the highest chelating activity as compared to other extracts (0.08 mg/mL, chelating activity 50%). The acetone extract was two times more active than acarbose against α-amylase enzyme and was the most active against α-glucosidase (6.3 mg/mL). Significant positive correlations were observed between total phenol content and α-glucosidase inhibitory assay and total terpene content and α-glucosidase inhibitory assay

Sample Preparation and Analytical Techniques in the Determination of Trace Elements in Food: A Review

International audienceEvery human being needs around 20 essential elements to maintain proper physiological processes. However, trace elements are classified as beneficial, essential, or toxic for living organisms. Some trace elements are considered essential elements for the human body in adequate quantities (dietary reference intakes, DRIs), while others have undetermined biological functions and are considered undesirable substances or contaminants. Pollution with trace elements is becoming a great concern since they can affect biological functions or accumulate in organs, causing adverse effects and illnesses such as cancer. These pollutants are being discarded in our soils, waters, and the food supply chain due to several anthropogenic factors. This review mainly aims to provide a clear overview of the commonly used methods and techniques in the trace element analysis of food from sample preparations, namely, ashing techniques, separation/extraction methods, and analytical techniques. Ashing is the first step in trace element analysis. Dry ashing or wet digestion using strong acids at high pressure in closed vessels are used to eliminate the organic matter. Separation and pre-concentration of elements is usually needed before proceeding with the analytical techniques to eliminate the interferences and ameliorate the detection limits

Antioxidant and anti-diabetic activities in commercial and homemade pomegranate molasses in Lebanon

International audiencePomegranate fruit and its derived products are rich sources of bioactive compounds. They have many biological activities. Pomegranate molasses (PM) is a thick, traditional Middle Eastern syrup used in many recipes for Lebanese and international cuisines. It is a highly nutritious product which makes it of great interest. The purpose of this study was to assess the phytochemical composition, antioxidant and anti-diabetic properties of homemade and commercial PM consumed in Lebanon using samples collected from households in rural areas (n = 4) and the market (n = 28). The objectives of this study were to determine their total phenolic content using the Follin-Ciocalteu method, their total flavonoid content using aluminum chloride method, their antioxidant activity using DPPH radical scavenging as well as ferrous ion chelating assays and their anti-diabetic activity using α-amylase and α-glucosidase inhibitory activities with acarbose, a known anti-diabetic drug, used as the standard reference. Homemade PM samples exhibited a higher antioxidant activity than commercial samples, with the most active homemade PM sample having IC50 values of 0.09 mg/mL (DPPH radical scavenging assay) and 46.78% ferrous ion chelating assay). Homemade PM samples also showed higher anti-diabetic activity than commercial samples, with the most active homemade PM sample having an IC50 of 0.63 mg/mL (α-amylase inhibitory activity) and of 0.41 mg/mL (α-glucosidase inhibitory activity) and being almost as active as acarbose with both enzymes (1.5 times).Significant inverse strong/moderate correlations were observed between total phenolic content/total flavonoid content and the IC50 value of DPPH radical scavenging assay, indicating positive associations between total phenolic and flavonoid contents and antioxidant activity. In addition, significant negative moderate correlations were observed between total phenolic/flavonoid contents and α-amylase inhibitory activity, indicating positive associations between total phenolic and flavonoid contents and anti-diabetic activity

Phytochemical composition, biological activities and antioxidant potential of pomegranate fruit, juice and molasses: A review

International audiencePomegranate fruit and its derived products (seeds, juice and mollassess) have been traditionally used in the prevention and treatment of chronic conditions, including cancer, cardiovascular disease, diabetes, Alzheimer's and arthritis. It has also been widely used in folk medicine as a remedy for conditions of the digestive tract, including parasitic worm infections, ulcers, diarrhea and aphthae. The pomegranate health benefits have been attributed to its bioactive compounds such as phenolic acids, flavonoids and tannins. These bioactive compounds were shown to have antioxidant and anti-diabetic activities as well as anti-inflammatory, anti-carcinogenic, anti-microbial, anti-diarrheal and neuro-protective properties. These pomegranate products are nowadays considered superfood and commonly used in many recipes in international cuisines. They are highly nutritious products rich in secondary metabolites with potent biological activities, which makes their study of great interest to researchers. The current review aimed to provide an up-to-date summary of findings of studies done to investigate the phytochemical composition biological activities, particularly antioxidant property of pomegranate and its products most importantly pomegranate molasses. In conclusion, this review shed the light on the rich phytochemical composition and many potent biological activities especially the antioxidant potential of pomegranate and its products

Chemical Composition, Antioxidant and Cytotoxic Activities of Roots and Fruits of Berberis libanotica

International audienc

The effects of BLE extract on sphere-forming ability of DU145 cells.

<p>(<b>A</b>) Sphere-Forming Unit (SFU) is shown with or without BLE treatment (20, 30, 60 and 100 µg/ml). Generated spheres are referred to as G1 (Generation 1) spheres. SFU is calculated according to the following formula: SFU  =  (number of spheres counted ÷ number of input cells) ×100. Data represent an average of three independent experiments. The data are reported as mean ± SD (* P<0.05; # P<0.01). (<b>B</b>) Representative images of DU145 prostaspheres with or without BLE treatment. Images were visualized by Carl Zeiss microscope at 10x magnification and analyzed by Carl Zeiss Zen 2012 image software. (<b>C</b>) Quantification of the average diameter of DU145 prostaspheres with or without treatment conditions. Data represent an average of three independent experiments. The data are reported as mean ± SD (* P<0.05; # P<0.01). (<b>D</b>) Quantification of the average number of cells per DU145 prostasphere with or without treatment. Data represent an average of three independent experiments. The data are reported as mean ± SD (* P<0.05; # P<0.01).</p

Summary of cell cycle analysis of PC3 cells by flow cytometry.

<p>Table showing the distribution of phases of the cell cycle under the effect of the BLE extract at 24, 48 and 72 h in PC3 cells. Cells that were left untreated with either vehicle or BLE (10 µg/ml and 30 µg/ml) are referred to as control. Data represent an average of three independent experiments. The data are reported as mean ± SD (<b>Bold</b>* P<0.05).</p><p>Summary of cell cycle analysis of PC3 cells by flow cytometry.</p

Summary of cell cycle analysis of DU145 cells by flow cytometry.

<p>Table showing the distribution of phases of the cell cycle under the effect of the BLE extract at 24, 48 and 72 h in DU145 cells. Cells that were left untreated with either vehicle or BLE (10 µg/ml and 30 µg/ml) are referred to as control. Data represent an average of three independent experiments. The data are reported as mean ± SD (<b>Bold</b> * P<0.05).</p><p>Summary of cell cycle analysis of DU145 cells by flow cytometry.</p

BLE extract induces cell death in DU145 prostate cancer cell lines.

<p>Cell death was determined by lactate dehydrogenase (LDH) assay treated with or without indicated concentrations of BLE extract for 24, 48 and 72 h. Cell death was calculated as the percentage of LDH release according to a previously mentioned formula. Data represent an average of three independent experiments. The data are reported as mean ± SD (* P<0.05; # P<0.01).</p