A STATISTICAL APPROACH BASED ON THE TOTAL ERROR CONCEPT FOR VALIDATION THE BIOANALYTICAL METHOD: APPLICATION TO THE SPECTROPHOTOMETRIC DETERMINATION OF TRACES AMOUNT OF ACETAMINOPHEN IN HUMAN PLASMA

Objective: The use of the classical approach of analytical validation, in practice or in the literature, is common. However, statistical verification, that looks separately the two errors (such as bias and precision) to make a decision, presents a risk to declare that an analytical method is valid while it is not, or conversely. To minimize this risk, a new approach based on the concept of total error was proposed. Methods: This approach proposes a calculation the two sided tolerance interval by combining the two errors; bias and precision, in order to examine the validity of an analytical and bioanalytical method at each concentration level. In this paper, we aim to demonstrate the applicability and simplicity of the both methods based on the total error approach: accuracy profile and uncertainty profile. This study will be illustrated by validation case of a spectrophotometric method for the determination of trace amounts of acetaminophen in human plasma. Results: After the introduction of the correction coefficient which is worth 1.16, the results obtained with accuracy profile approach show clearly that the bioanalytical method is valid over a concentrations range of [100.34- 500] µg mL-1 since the upper and lower 90%-expectation tolerance limits have fallen within the two acceptance limits of ± 20%. The same results found using the uncertainty profile approach because the "two - sided 66.7%-content, 90% -confidence tolerance intervals "are found within two acceptance limits of ± 20% over the range of [170; 500] µm mL-1. Conclusion: The excellence of the total error approach was showen since it enables successfully to validate the analytical procedure as well the calculation of the measurement uncertainty at each concentration level

L'aviculture non industrielle au Maroc: Une étude par enquête dans la région de Rabat-Salé-Kénitra

Traditional poultry farming is an important alternative for the increase in the animal protein contribution in the rural environment. Surveys were carried outin 98 poultry farms in four provinces of the Rabat-Salé-Kénitra region to characterize the traditional poultry farming in this region. These surveys focused on the characteristics of the farms (socio-economic status of the farmer, the farming method, and the composition of the poultry, the avian species, the infrastructure, the business, the feed, the diseases, the mortality rate and the treatments used).The analysis of the collected data showed that women are primarily responsible for poultry farming (80%); 94.9% of the surveyed breeders have no technical training in poultry farming; the experience in the surveyed farms varies between 10 and 50 years (p <0.0001); high numbers of poultry are included in the majority (49%) between 20 and 100 individuals; poultry feed in the study areas was based primarily on natural resources (28%), followed by bran (23%) and wheat (22%); the most common diseases in the “Beldi chicken” are coccidiosis (22%) and avian influenza (21%), followed by E. coli (16%) and smallpox (11%). The majority of breeders practice traditional treatments (63%), whereas only 37% of breeders used veterinary treatments (p <0.001). Thus, poor production performance is recorded in these farms: a median mortality rate of 10% is related to the characteristics of the farms and farmers (Technical training, level of hygiene practiced in farms, etc.). Diseases, lack of supervision and financial means are the main constraints of the sector. Keywords: Traditional poultry farming, poultry diseases, traditional treatments, surveys, food, Rabat-Salé-KénitraDes enquêtes ont été menées dans 98 exploitations avicoles réparties sur 4 provinces de la région de Rabat-Salé-Kénitra afin de caractériser les élevages avicoles traditionnels de cette région. Ces enquêtes ont porté sur les caractéristiques des élevages (état socio-économique de l’éleveur, mode d’élevage, la composition de la basse-cour, les espèces aviaires, l’infrastructure, la commercialisation, l’alimentation, les maladies, le taux de mortalité et les traitements utilisés). L’analyse des données recueillies a montré que les femmes sont les principales responsables des élevages avicoles (80%) ; 94.90% des éleveurs enquêtés n’ont aucune formation technique en aviculture; l’expérience dans les élevages enquêtés varie entre 10 et 50 ans (p<0,0001); les effectifs de volailles élevés sont compris en majorité (48,98%) entre 20 et 100 individus ; la nourriture de la volaille dans les régions étudiées était basée essentiellement sur les ressources naturelles (28%), suivi par le son (23%) et le blé (22%); les maladies les plus répondues chez le poulet Beldi sont la coccidiose (22%) et la peste aviaire (21%), suivis par E.Coli (16%) et la variole (11%). La majorité des éleveurs pratiquent des traitements traditionnels (63%), alors que seuls 37 % des éleveurs avaient recours aux traitements vétérinaires (p < 0,001). Ainsi, de faibles performances de production sont enregistrées dans ces élevages : une valeur médiane du taux de mortalité de 10 %, a une relation avec les caractéristiques des exploitations et des exploitants (Formation technique, niveau d’hygiène pratiqué dans les élevages etc..). Les maladies, le manque d’encadrement et de moyens financiers constituent les principales contraintes de la filière. Mots clés: L'aviculture traditionnelle, maladies avicoles, traitements traditionnels, enquête, alimentation, Rabat-Salé-Kénitr

Unassisted and carbon dioxide-assisted hydro- and Steam-distillation: modelling kinetics, energy consumption And chemical and biological activities of volatile oils

The demand for more suitable eco-friendly extraction processes has grown over the last few decades and driven research to develop efficient extraction processes with low energy consumption and low costs, but always assuring the quality of the volatile oils (VOs). The present study estimated the kinetic extraction and energy consumption of simultaneous hydro- and steam-distillation (SHSD), and SHSD assisted by carbon dioxide (SHSDACD), using an adopted modelling approach. The two isolation methods influenced the VOs yield, chemical composition and biological activities, namely, antioxidant, anti-glucosidase, anti-acetylcholinesterase and anti-inflammatory properties. SHSDACD provided higher VOs yields than the SHSD at a shorter extraction time: 2.8% at 30 min vs. 2.0% at 120 min, respectively, for Rosmarinus officinalis, 1.5% at 28 min vs. 1.2% at 100 min, respectively, for Lavandula angustifolia, and 1.7% at 20 min vs. 1.6% at 60 min, respectively, for Origanum compactum. The first order and sigmoid model fitted to SHSD and SHSDACD, respectively, with R2 value at 96% and with mean square error (MSE) < 5%, where the k distillation rate constant of SHSDACD was fivefold higher and the energy consumption 10 times lower than the SHSD. The rosemary SHSD and SHSDACD VOs chemical composition were similar and dominated by 1,8-cineole (50% and 48%, respectively), and camphor (15% and 12%, respectively). However, the lavender and oregano SHSDACD VOs were richer in linalyl acetate and carvacrol, respectively, than the SHSD VOs. The SHSDACD VOs generally showed better capacity for scavenging the nitric oxide and superoxide anions free radicals as well as for inhibiting α-glucosidase, acetylcholinesterase, and lipoxygenase.info:eu-repo/semantics/publishedVersio

AN INNOVATIVE STRATEGY BASED ON UNCERTAINTY PROFILE FOR THE VALIDATION OF MICROBIOLOGICAL METHODS FOR COUNTING ENTEROBACTERIACEAE IN FOODS

Objective: A new and powerful statistical approach known as the uncertainty profile concept has been suggested for both testing the validity and making easy and straightforward interpretation of results obtained during the validation of an analytical method. The main goal of this paper is to confirm the applicability of this new strategy for the validation of a commercial kit, microbiological method, for the enumeration of the Enterobacteriaceae in foods and the estimate of the measurement uncertainty by using the newly provided formula and without referring to any additional experiments.Methods: An innovative formula to assess the uncertainty by using validation data and without recourse to other additional experiments was proposed. The uncertainty was evaluated through the two-sided β-content, γ-confidence tolerance interval, which is computed with three manners: the Mee's approach, the Generalized Pivotal Confidence, and the Modified Large Simple procedureResults: After the use of the three chemometric method of calculation of tolerance intervals, the obtained results with uncertainty profile show without doubt that the enumeration method is valid over the range of target values given that the upper and the lower 66.7 %-content, 90 %-confidence tolerance limits have fallen within the two acceptance limits of±0.25 Log unit. If the β is stretched to 80 %-content, 90 %-confidence, the three computed tolerance intervals lead to different decisions.Conclusion: we have demonstrated the ability of the uncertainty profile to be used for testing the validity of enumeration method which represents the first application of an uncertainty profile to food microbiological methods, and provides good estimations of the uncertainty measurements for each concentration level.Keywords: Validation, Uncertainty profile, β-content-γ-confidence tolerance interval, Uncertainty measurement, Microbiological metho

A preliminary study on the potential of front face fluorescence spectroscopy for the discrimination of Moroccan virgin olive oils and the prediction of their quality

International audienceThis study examines the feasibility of using front face fluorescence spectroscopy (FFFS) to authenticate 41 virgin olive oil (VOO) samples collected from 5 regions in Morocco during 2 consecutive crop seasons

Preliminary study on the potential application of Fourier‐transform mid‐infrared for the evaluation of overall quality and authenticity of Moroccan virgin olive oil

International audienceBACKGROUND Olive oil provides a wide range of health-promoting compounds. The quality of olive oil is an even more complex concept as it is affected by several factors, such as variety, season, stage of maturation, extraction processing, and so on. The main objective of this study was to determine the potential of chemical and mid-infrared spectroscopy techniques to determine the quality and authenticity of virgin olive oil (VOO). For this, we studied 41 VOOs originating from five regions of Morocco (Fez/Meknes, Eastern, Northern, Beni-Mellal/Khenifra, and Marrakech/Safi) and produced using different agricultural and technological conditions during two successive crop seasons (2015-2016 and 2016-2017).RESULTS By applying principal component analysis and factorial discriminant analysis with leave-one-out validation to the mid-infrared spectroscopy, clear discrimination between VOO samples according to their geographic origin and variety was observed, with correct classification rates of 91.87% and 91.87% being observed respectively. The application of partial least-squares regression to mid-infrared and chemical data sets allowed excellent prediction of free acidity, peroxide value, k(270), and chlorophyll level with R-2 of 0.99, 0.97, 0.98, and 0.93 respectively, and good prediction of k(232) (R-2 = 0.84).CONCLUSION The results demonstrate that mid-infrared spectroscopy coupled with chemometric tools could be used as a rapid screening tool for evaluating the overall quality and authenticity of VOO. (c) 2020 Society of Chemical Industr

Application of new emerging techniques in combination with classical methods for the determination of the quality and authenticity of olive oil: a review

International audienc