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1.
BioTech (Basel) ; 13(1)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38534916

RESUMO

(1) Background: Cumin seeds, extracted from the plant Cuminum cyminum, are abundant in phenolic compounds and have been extensively researched for their chemical makeup and biological effects. The objective of this research is to enhance the water extraction of polyphenols through the water bath (WB) technique and to evaluate the antiradical, antibacterial, and anticancer effects of the extract. (2) Methods: Response Surface Methodology was used to find the best parameters to extract polyphenols. Three experimental parameters, time, temperature, and solid-liquid ratio, were tested. The disc diffusion method has been used to determine the antimicrobial activities against Salmonella Typhimurium, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Candida albicans. The antiradical activity was performed using the DPPH method, while total phenolic content was performed using Folin-Ciocalteu. High-Performance Liquid Chromatography (HPLC) was conducted to analyze the phytochemical profile of WB extracts. The anticancer activity of the lyophilized extract was assessed against three cancer cell lines (colon (HT29), lung (A549), and breast (MCF7) cancer cell lines).; (3) Results: The optimal conditions for water extraction were 130 min at 72 °C. The total phenolic compounds yield (14.7 mg GAE/g DM) and antioxidant activity (0.52 mg trolox eq./mL) were obtained using a 1:40 solid-liquid ratio. The primary polyphenols identified were the flavonoids rutin (0.1 ppm) and ellagic acid (3.78 ppm). The extract had no antibacterial or antifungal activities against the microorganisms tested. The extract showed anticancer activity of about 98% against MCF7 (breast cancer cell line), about 81% against HT29 (colon cancer cell line), and 85% against A549 (lung cancer cell line) at high doses. (4) Conclusions: Extraction time and a high solid-liquid ratio had a positive impact on polyphenol recovery and in maintaining their quantity and quality. Furthermore, the optimal aqueous extract exhibited strong antiradical activity reflected by the inhibition of free radicals in addition to a significant specificity against the tested cancer cell lines.

2.
Sci Rep ; 13(1): 12547, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532740

RESUMO

A huge-amount of citrus by-products is being wasted every-year. There is a high-need to utilize these by-products with high-efficiency. This study focuses on the essential oil (EO) isolation from the zest of Citrus sinensis (CS) by-products, using a novel dual-function gas-chromatography mass-spectrometry optimized ultrasound-assisted hydrodistillation-prototype (DF-GC/MS-HUS). The CS-EO was GC-analyzed by MS-detector (GC/MS) and optimized by flame-ionization detector (GC/FID). Ultrasound-assisted hydrodistillation (HUS) had a dual-function in CS-EO isolation by utilizing an adequate-energy to break-open the oil-containing glands, and by functioning-as a dispersing-agent to emulsify the organic-phase. The most effective DF-GC/MS-HUS optimized-conditions were isolation under 38 °C and 10 min of 28.9 Hz sonication. The main-components of CS-EO were limonene, ß-myrcene, and α-pinene (81.32%, 7.55%, and 4.20%) in prototype, compared to (60.23%, 5.33%, and 2.10%) in the conventional-method, respectively. The prototype CS-EO showed natural antibacterial-potentials, and inhibited the bio-film formation by Staphylococcus aureus, Listeria monocytogenes, and E. coli more-potent than the conventional-method. Compared to conventional-method, the prototype-method decreased the isolation-time by 83.3%, lowered energy-consumption, without carbon-dioxide production, by reducing isolation-temperatures by more-than half, which protected the thermolabile-components, and increased the quantity by 2514-folds, and improved the quality of CE-EO composition and its antibacterial-potentials. Therefore, the DF-GC/MS-HUS prototype method is considered a novel green-technique that minimized the energy-utilization with higher-efficiency.


Assuntos
Citrus sinensis , Citrus , Óleos Voláteis , Escherichia coli , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/química , Compostos Fitoquímicos/análise , Antibacterianos , Bactérias , Citrus/química
3.
Food Chem ; 374: 131676, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34896950

RESUMO

Pesticide residues can be found in foods of plant origin which can cause adverse health effects. The aim of this study is to assess the risk of exposure to pesticide residues (180) from foods (478 samples of 49 food items) of plant origin collected in Beirut, Lebanon. Pesticides were extracted by QuEChERS method and analyzed through liquid and gas chromatography tandem mass spectrometry. Of the 387 samples, 58 (32.2%) residues were detected. Over 50 % of the positive samples for 14 residues were exceeding the Maximum Residue Limits of European Union. All of the hazard quotient (HQ) values were less than 1 with respect to all age groups except for the pesticide residue chlorpyrifos in cucumber (1.7945). This suggests that the majority of foods examined for the pesticide residues can be considered safe for consumption by Lebanese children, although Chlorpyrifos in cucumber was of concern.


Assuntos
Resíduos de Praguicidas , Criança , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Líbano , Resíduos de Praguicidas/análise , Medição de Risco
4.
Vet World ; 15(11): 2575-2586, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36590110

RESUMO

Background and Aim: Cheese is considered an essential component of the Lebanese table, however, several foodborne illnesses have been reported due to cheese consumption. This study aimed to assess the microbiological quality and the occurrence of antibiotic and pesticide residues in two traditional Lebanese cheeses, Akkawi and Baladiyeh. In addition, drug resistance of isolated pathogens from the cheese samples was evaluated. Materials and Methods: Fifty Akkawi and Baladiyeh cheese samples were obtained in duplicate from 37 different commercial brands in supermarkets and shops from various regions of Lebanon. Samples of different weights were either individually vacuum packed or soaked in brine unpacked where it was placed in plastic bag after being purchased. Samples were homogenized to determine antibiotic and pesticide residues using liquid and gas chromatography coupled to mass spectrometry, and microbiological evaluation was performed according to the International Organization for Standardization reference analytical methods. The disk diffusion method was used to determine the susceptibility of these isolates to antibiotics. Results: Microbiologically, 17% of Akkawi and 14% of Baladiyeh samples were found to be non-conforming. The bacterial isolates (n = 29) were tested for their susceptibility to 11 different antibiotics commonly prescribed in the Lebanese community or used for treating infections caused by Gram-negative bacteria and listeriosis. Each isolate was found to be resistant to at least three antibiotics. Liquid and gas chromatography coupled to mass spectroscopy analysis showed the absence of pesticide residues in all samples. However, sulfamethazine antibiotic residue was found in 14% of the samples. Conclusion: The results suggest that the cheese samples tested could cause foodborne illnesses due to the detection of pathogenic bacteria and are a public health concern due to the presence of antibiotic residues and the transmission of multidrug-resistant organisms.

5.
Vet World ; 14(6): 1644-1649, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34316215

RESUMO

BACKGROUND AND AIM: Transfer of antibiotics from raw milk to derived products is directly related to the processes involved in the manufacturing of dairy products, including East Mediterranean cheeses, since these have particular flow diagrams of production. The aim of this study was to assess the effects of skimming, pasteurization, curding, pressing, salting, cheese boiling, and whey acidification/heating on two widely used antibiotics in Lebanon, oxytetracycline (OTC) and tylosin (TYL), in the manufacture of commonly consumed cheeses in the East Mediterranean. MATERIALS AND METHODS: Four hundred and fifty kilograms of full-fat bovine milk were spiked with OTC and TYL, then skimmed and pasteurized using holder and high-temperature short-time (HTST) methods. Milk was then processed to make cheeses (23 kg Baladi, 20 kg Akkawi, 20 kg Halloum, and 18 kg Double Cream). Liquid chromatography-mass-spectrometry was used to measure antibiotics. Analysis was performed using Statistical Package for the Social Sciences v25. RESULTS: Skimming significantly (p=0.015) decreased TYL concentration by 68.6%. OTC degradation during holder (41-54%) proved to be significant (p=0.015). HTST had a significant (p=0.012) effect on TYL with 32% degradation. Curding step in making Baladi had a significant (p=0.028) effect on OTC only with the concentration increasing by 1.5-fold. Acidification and heating of whey to produce Double Cream decreased significantly (p=0.037) OTC concentration (14.7-46.3%), while TYL concentration increased significantly (p=0.000) by 300%. Pressing and salting in making Akkawi did not have any significant effect, while cheese boiling in making Halloum significantly decreased both antibiotics. CONCLUSION: OTC is transferred to Baladi and Akkawi (curd based) mainly, while double cream (whey based) has a high level of TYL transfer. Hence, people who consume these cheeses excessively could be exposed to high amounts of both antibiotics and thus be prone to their detrimental effect on health.

6.
Heliyon ; 6(12): e05524, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33319086

RESUMO

Countrywide pesticide management activities are resource draining, even for developed countries, which sometimes fall short in achieving the optimum protection against pesticides deleterious effects on humans and environment. Additionally, in Lebanon, basic flaws exist at different levels of pesticide management cycle. In this study, through an extensive review of relevant literature regarding the pesticides impact on humans and environment in Lebanon and adopted policies in existing legislation, several gaps have been identified. Accordingly, recommendations to reduce pesticide risk through a combination of reforms at the policy level and its tools, particularly legislation, are proposed. In our opinion, the starting point is to adopt a minimum list of lower risk pesticides supported by a combination of: "prescriptions" based on a comprehensive registration and an effective implementation systems, a suitable IPM/ICM government-supported credit system, traceability systems of agricultural commodities and pesticides containers, Pesticide stock management system to reduce the quantity of obsolete pesticides, and containers recycling system. For a global sustainability of pesticides risk reduction, a binding global intervention fostered by the UN, based on human rights for safe food, is called upon to ban hazardous pesticides-except those of WHO class IV- trafficking in developing countries scoring low in an international official assessment of their pesticides lifecycle management. At the same time, global funds should support pesticides alternatives and the enhancement of the developing countries capacities for pesticides lifecycle management, which is a part of a larger global matrix in risk reduction.

7.
Heliyon ; 6(9): e04995, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32995645

RESUMO

One of the drawbacks of canning is the migration of various chemicals from the package into the food product. This work aimed at analyzing the concentrations of Bisphenol A (in 137 samples) and heavy metals (in 51 samples) of canned tuna commercialized in Lebanon while evaluating the variability across different brands, packing media, layer, and proximity to the expiry date. Accordingly, BPA was detected in 12 samples out of the 137 samples, run in duplicates. The estimated daily intake of BPA for the selected samples (n = 274) was lower than the tolerable daily intake of BPA, 0.004 mg/kg/day. Therefore, there is no health risk associated with BPA as a result of consuming canned tuna commercialized in the Lebanese market. Besides, the study has shown that 66 samples out of 102 were contaminated with Zn whereas 100% of the samples were contaminated with Aluminum and Tin. However, the calculated Health Risk Index of all the considered heavy metals are all within the safe limits as defined by EFSA (European Food Safety Authority) and Codex Alimentarius.

8.
Toxics ; 7(3)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370330

RESUMO

Occupational exposures and current diet are both sources of environmental contaminants that can be transferred in the mother's body. These chemicals can definitely penetrate to the developing foetus and the nursing infant from contaminated breast milk during the lactation period. Nowadays, one of the special interests is the exposure of new-borns to toxic chemicals such as pesticides and antibiotics reported in human milk due to their potential harms, especially developmental deficits in early childhood. The aim of our current study was to assess the occurrence of pesticide residues and antibiotic residues contamination in breast milk collected from Syrian refugee lactating mothers residing in North Lebanon Camps. A total of 120 breast milk samples (40 in triplicate) were collected from camps in Akkar, North Lebanon using an electrical pump. A survey was administrated to determine socio-demographic characteristics, dietary and smoking habits and medical history of participating lactating mothers. The milk samples were analysed for the presence of antibiotic residues and pesticide residues using liquid and gas chromatography tandem mass spectroscopy (LC-MS/MS) and Gas Chromatography-Tandem Mass Spectrometry (GC-MS/MS). This study reported the absence of antibiotic residues in 96.66% of our samples (n = 120) and the presence of pesticides residues in only 5% of our total breast milk sample. Our results considered the breast milk collected from Syrian refugee lactating mothers as safe from chemical contamination. It is worth conducting more studies on other Syrian refugee camps to test the effect of camp living conditions on breast milk safety.

9.
Antibiotics (Basel) ; 8(2)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141997

RESUMO

Antibiotic residue in chicken is a human health concern due to its harmful effects on consumer health. This study aims at screening the antibiotic residues from 80 chicken samples collected from farms located in different regions of Lebanon. An optimized multi-class method for identification and quantification of 30 antibiotics from four different chemical classes (sulfonamides, tetracyclines, quinolones, and beta-lactams) has been developed by using liquid chromatography-mass spectrometry. The evaluation of antibiotics residues in 80 chicken muscles samples has shown that 77.5% of samples were at least contaminated with antibiotics residues, out of which 53.75% were exposed to co-occurrence of multidrug residues. The screening of the four antibiotics families has shown that ciprofloxacin (quinolones) represents the highest occurrence percentage (32.5%), followed by amoxicillin (ß-lactams) (22.5%) and then tetracyclines (17.5%). Means of sarafloxacin, amoxicillin, and penicillin G residues levels were above the Maximum Residue Limit (MRL) recommended limit according to the European Union EC. This study revealed that chicken samples collected from Lebanese farms contain antibiotic residues. Guidelines for prudent use of antimicrobials agents for chicken should be adopted to reduce the prevalence of resistant Salmonella in chicken.

10.
Antioxidants (Basel) ; 7(12)2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30486336

RESUMO

The valorization of industrial food byproducts by means of environment-friendly extraction methods is becoming a major interest because of its environmental and economic values. In this study, the efficiency of many technologies, such as ultrasounds (US), microwaves (MW), and infrared (IR), was compared, in terms of polyphenol yield and bioactivity from apricot pomace. IR was the most effective method with the highest polyphenol (10 mg GAE/g DM), flavonoid (6 mg CE/g DM), and tannin (3.6 mg/L) yields. In terms of efficacy, IR was followed by MW, US, then solid-liquid (S/L) extraction. IR extract from apricot pomace exhibited the highest inhibitory activity against all the studied gram-positive strains (Methicillin Resistant Staphylococcus aureus, Staphylococcus aureus, Methicillin-resistant Staphylococcus epidermidis, and Staphylococcus epidermidis) and a one gram-negative strain (Escherichia coli). Moreover, IR extracts had by far the highest antiradical activity (AC) (40%) followed by MW (31%), US (28%), and then S/L (15%). High-performance liquid chromatography (HPLC) permitted the identification and quantification of rutin in all extracts; whereas catechin was detected in those of IR (3.1 µg/g DM), MW (2.1 µg/g DM), and US (1.5 µg/g DM). Epicatechin was exclusively found in IR extract (4 µg/g DM), suggesting the selectivity of IR towards this compound. Scanning electron microscopy (SEM) revealed that the IR technique induced the highest cellular and structural damage in apricot pomace, which could explain the effectiveness of this technology.

11.
J Am Chem Soc ; 132(24): 8234-5, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20509648

RESUMO

The nitrogen oxides (NO(x)) decomposition on illuminated TiO(2) surfaces has been widely studied, but little is known about the subsequent formation of non-nitrogen containing products. In this study, TiO(2) coated glass surfaces and TiO(2) films with nitrate anions (either premixed with TiO(2) as KNO(3) or deposited from gaseous NO(x)) are irradiated with broad-band light. Upon irradiation, detected gas phase products include NO(2), HNO(2), and O(3). To the best of our knowledge, this is the first study that reveals the production of O(3) from TiO(2) surfaces. By surface charge transfer reactions, nitrate anions are oxidized into nitrate radicals and their photochemistry (almost in the visible) leads to O(3) formation, enhancing the oxidizing power of these surfaces.

12.
J Phys Chem A ; 112(6): 1268-76, 2008 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-18205335

RESUMO

The interactions of ozone with benzophenone and phenol solid films have been investigated under simulated atmospheric conditions with respect to relative humidity, pressure, temperature, and O3 concentration using a coated flow tube reactor. The steady-state reactive uptake coefficients (gammass) of ozone on benzophenone films ranged from below 10(-6) in dark conditions to approximately 4 x 10(-6) under UV-A irradiation and decreased with increasing O3 concentration in the range 28-320 ppbv. A similar trend was observed for the initial uptake coefficient (gammai) which varied from ca. 1.5 x 10(-6) in the dark to approximately 7 x 10(-6) under UV-A irradiation. The uptake coefficients under irradiation were strongly dependent on the relative humidity (from 5 to 70%), with their lowest values at high humidity (70% RH). The ozone uptakes for multilayer coverage turned out to be independent of the deposited mass of the organic compound. The benzophenone-phenol mixture also showed photoenhanced uptake with a larger steady-state uptake under visible irradiation, approximately 2.9 x 10(-6). Contact angle measurements showed an increase of the organic film hydrophobicity for the benzophenone-phenol mixture upon combined exposure to light and ozone. A linear dependence of the kinetic values on the photon flux has been demonstrated and when extrapolated to the solar spectral irradiance would lead to uptake coefficients of approximately 10(-5). UV-vis analysis and contact angle measurements of the organic film after irradiation and ozone exposure showed relevant changes only in the mixture, with an increase in the hydrophobic character of the film and the appearance of a new absorption band up to 450 nm.

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