Effect of stage of lactation on the physical and chemical composition of Drâa goat milk

Raw milk characterization constitutes a preliminary and an important step to take account in order to obtain an optimal technological valorization. Among other factors, breed, feed and stage of lactation are the most important factors that influenced cheese making and other dairy products valorization. Thus, this study proposes to analyze the physicochemical composition of Drâa goat milk and to study raw milk fluctuations throughout a complete lactation period. The study was carried out in the Experimental Station of Errachidia (Southern Morocco). In this context, sixteen goats were selected and sampled every week during a period of 160 days (average lactation length). A total of 128 samples of raw goat milk were analyzed according to international standards. Analyses were focused to determination of pH, acidity, density, Dry Matter (DM), Solids Non Fat (SNF), ash, fat and Total Nitrogenous Matter (TNM). Average values were about 17.8°D for acidity, 13.3% for Dry Matter, 0.73% for ash, 4.16% for fat and 3.60% for Total Nitrogenous Matter. In general, theses values are largely situated in the upper level of the range suggested by several Moroccan and foreign researchers for other goat species. On the other hand, the evolution of physical and chemical parameters throughout  lactation stages showed that dry matter, fat content and total nitrogenous matter increased significantly throughout the lactation period; the opposite was found for density (p<0.001). No significant (p>0.05) changes were shown for milk acidity and the average found was around 17°D. Content of milk ash increased significantly during the late lactation stage compared to the earliest and the opposite was observed for pH.The results of the  present investigation show that Drâa goat milk is rich with desirable  components like fat and protein for dairy product manufacturers, and that the late lactation stage seems to be the best period to ensure an optimum technological valorization.Key words: Goat, Morocco, milk, physicochemical, lactatio

Changes Evaluation of Reserve Substances and Degradation Enzymes after Exposure of Tomato Plants (Lycopersicon esculentum Mill.) to Alpha - Cypermethrin, Chlorpyriphos and Pyrimicarb

Tomato (Lycopersicon esculentum Mill.) is one of the most important vegetables, whose production and consumption increased quite rapidly. The impact of three xenobiotics such as alpha-cypermethrin, chlorpyriphos and pyrimicarb on reserve substances (proteins, starch and lipids) and degradation enzymes (protease and alpha-amylase) was investigated. The effect of the insecticides was observed by using four dilutions of the normal concentration used in agriculture (100%, 75%, 50% and 25%) for germinating seeds, and only the recommended concentration in agriculture for growing plants. The results suggest that the tested insecticides induced an accumulation of proteins in both treated seeds, and treated plants leaves and roots. Moreover, the protease activity was reduced in treated seeds and plants. Also a great accumulation of starch in presence of the insecticides was registered in treated seeds, and leafs and roots of treated plants, whereas this accumulation is accompanied with an inhibition of alpha-amylase activity. Concerning lipids, a significant increase was observed in treated samples compared to the control ones

Activité Acaricide Des Huiles Essentielles Du Mentha Pulegium, Origanum Compactum Et Thymus Capitatus Sur L’acarien Phytophage Tetranychus Urticae Koch (Acari : Tetranychidae)

The use of botanical acaricides extracted from plants as an alternative to replace the chemical acaricides is an interesting and efficient option to control pests and ameliorate their toxic effects to humans and the environment. The aim of this work was to evaluate the contact toxicity of Pennyroyal mint (Mentha pulegium), oregano (Origanum compactum) and thyme (Thymus capitatus) essential oils against adults, larvae and eggs of two-spotted spider mite Tetranychus urticae Koch (Tetranychidae). The chemical composition of these three plant essential oils was also characterized. Laboratory tests were conducted to determine the acaricidal effect of plant essential oils at several doses in geometric progression. The consequences of treatments on mortality were measured in relationships with concentrations of essential oils. On the other hand, the major constituents of the three essential oils were identified by gas chromatography-mass spectrometer (GC-MS) techniques. GCMS analyses proved that the major compound present in the essential oils of thyme and oregano is carvacrol (55.59 and 55.28% respectively) while the main component of pennyroyal mint essential oil is pulegone (67,63%). Laboratory bioassay results indicated that essential oils of thyme and pennyroyal mint caused the most important acaricidal effects in comparison with the essential oil of oregano. At a concentration of 1%, thyme and pennyroyal eradicate all adults of the mite while oregano causes a mortality of 84.99%. On larvae, the mortality rate of thyme, pennyroyal and oregano is 97.7; 89.47 and 57.89% respectively. The results of the present study concluded that plant essential oils could be useful in promoting research aiming at the development of new agent for pest control from the plants with medicinal values

Research and Toxinogenic Characterization of Penicillium Contaminating Goat's Traditional Dairy Products in Northern Morocco

The goat rearing in northern Morocco had known a very important evolution with the introduction of European breeds of goats more productive of milk compared to local breeds. Moulds are common contaminants in many traditional dairy products. Some species are responsible for significant economic losses and major public health problems by producing toxic metabolites like mycotoxins. This work aims to isolate, identify and characterize the mycotoxin-producing species of Penicillium from milk and traditional cheese (Jben) in the different northern region of Morocco, based on microbiological analysis and in vitro identification of Penicillium toxinogenic by fluorescence detection and HPLC analysis. Our microbiological analysis clearly show that the fungal flora is highly developed in goat's milk and Jben: 85 mould and yeast isolates from 57 samples collected. The rate of fungal flora (mould and yeast species) is high, it is around 2,6 104 CFU/ml in milk and 5,90 104 CFU/g in Jben. Penicillium isolates were purified and identified according to macroscopic and microscopic criteria. The proportion of Penicillium (61,53 %) in milk is more than Jben (16,94 %). The most important Penicillium species in two dairy products are P.italicum (23,1% in milk against 5,1 % in Jben), P. cyclopium (7,7 % in milk against 5,1% in cheese), and P. expansum (7,7% in milk against 3,4 % in cheese). According to in vitro identification of Penicillium toxinogenic by fluorescence detection, the majority of Penicillium isolates were able to produce mycotoxin type Citrinin and Ochratoxin A. The capacity of mycotoxin production by the identified strains was confirmed by High-Performance Liquid Chromatography Analysis. The patulin was produced by all Penicillium isolates, while the citrinin was produced by P. nalgiovense, P. simplicissimum, and P. dipodomyis. Unlike the ochratoxin A was produced by all isolates, except the P. nalgiovense and P. dipodomyis. The presence of toxicogenic Penicillium species in Moroccan traditional goat's dairy products suggeststhat contaminated products according to processing conditions and after storage traditionally could be a risk to the health and safety of consumers. The awareness-raising measures, the professional guidance on the concept of hygienic quality and the tendency to semi-industrial production remain worksites to work more efficiently by the state

Toxicity of Rosmarinus Officinalis Essential Oil to the Pest Tetranychus Urticae Koch (Acari%253A Tetranychidae) and its Predator Phytoseiulus Persimilis Athias-Henroit (Acari%253A Phytoseiidae)

This study aims to determine the chemical composition of Rosmarinus officinalis (Lamiales%253A Lamiaceae) and its acaricidal effect on the pest mite Tetranychus urticae Koch (Acari%253A Tetranychidae). and its predator Phytoseiulus persimilis Athias-Henroit (Acari%253A Phytoseiidae). The analysis of the chemical composition of the essential oil extracted was carried out on gas chromatography coupled with mass spectrometry. Three major compounds found in the essential of R. officinalis were alpha%253B-pinene (32.64%25), beta%253B-Humulene (8.71%25), and Camphene (5.95%25). The toxicity of R. officinalis oil was performed using inhalation bioassay on both T. urticae and its predator P. persimilis. The results obtained showed high toxicity on the mite than to its predator with a mortality rate of 80%25 and 16.11%25 respectively at the dose of 4%25. The fertility of females, the hatching of eggs, and the emergence of adults in T. urticae were also studied using contact bioassay where a total reduction of all three biological parameters was recorded at the dose of 4%25. Besides, the application of this oil will also allow the conservation of P. persimilis. Altogether, the combination of toxicity on T. urticae and preservation of its predator gives R. officinalis essential oil a propitious potential for the control of the pest mite T. urticae and maintenance of environmental balance

Evaluation des critères physiques, physicochimiques et biochimiques et des activités biologiques des graines et des huiles des graines du fenouil (Foeniculum vulgare Mill.)

The fennel is a typical plant of the Mediterranean region used in traditional pharmacopoeia and as an aromatic spice. This study was interested in an evaluation of the physical, physicochemical and biochemical criteria and the biological activities of the seeds and seeds oils of local (beldi) fennel produced at four stages of maturity in four terroirs of Essaouira province (Central West, Morocco), compared to those of a local fennel produced in a neighboring terroir and an imported fennel. Seeds of different maturity stages and geographic origins were clearly differentiated into homogeneous groups according to studied criteria. The water activity of these seeds is between 0.43 and 0.51 with an average ash content of 6.24 g/100 g of dry matter (DM) containing fairly high contents of potassium, calcium, sodium and baryum. Seed total polyphenols recorded interesting levels ranging between 623.64 and 959.24 mg gallic acid equivalent/100 g DM. The antioxidant activity is estimated between 23.53 and 43.83 mg ascorbic acid equivalent/g DM. Yields of vegetable and essential oils varied from 8.55 to 16.28 % and from 1.4 to 2.7 %, respectively. However, the high values recorded for free acidity, peroxide index and specific extinction of vegetable oil indicate that it cannot be considered as edible oil. Concerning the essential oil, significant increases in the aroma compounds s-limonene and fenchone were noted during maturity. Besides, the antibacterial activity tests have shown that Staphylococcus aureus is sensitive to the action of this essential oil. Moreover, the quality criteria of the studied fennel seeds and seed oils showed the influence of the geographical origin. These results would make it possible to propose ways of valorizing, quality control and labeling of beldi fennel under a distinctive sign of origin and quality.Le fenouil est une plante typique de la région méditerranéenne utilisée dans la pharmacopée traditionnelle et comme épice aromatique. Cette étude s’est intéressée à une évaluation des critères physiques, physicochimiques, biochimiques et des activités biologiques des graines et des huiles des graines du fenouil local (beldi) produit à quatre stades de maturité dans quatre terroirs de la province d’Essaouira (Centre-Ouest du Maroc), comparées à celles d’un fenouil local produit dans un terroir limitrophe et d’un fenouil importé. Les graines de stades de maturité et d’origines géographiques différents ont été nettement différenciées dans des groupes homogènes selon les critères étudiés. L’activité de l’eau de ces graines est comprise entre 0,43 et 0,51 avec une teneur moyenne en cendres de 6,24 g/100 g de la matière sèche (MS) renfermant des teneurs assez importantes en potassium, calcium, sodium et baryum. Les polyphénols totaux des graines ont enregistré des teneurs intéressantes variant entre 623,64 et 959,24 mg équivalent acide gallique/100 g MS et l’activité antioxydante de ces graines est estimée entre 23,53 et 43,83 mg équivalent acide ascorbique/g MS. Les rendements en huile végétale et huile essentielle ont varié de 8,55 à 16,28 % et de 1,4 à 2,7 %, respectivement. Toutefois, les valeurs élevées enregistrées pour l’acidité libre, l’indice de peroxyde et l’extinction spécifique de l’huile végétale renseignent qu’elle ne peut être considérée comme une huile alimentaire. Concernant l’huile essentielle, des augmentations significatives des composés d’arôme s-limonène et fenchone ont été notées au cours de la maturité. En outre, les tests de l’activité antibactérienne ont montré que Staphylococcus aureus est sensible à l’action de cette huile essentielle. Par ailleurs, les critères de qualité des graines et des huiles des graines de fenouil étudiés ont montré l’influence de l’origine géographique. Ces résultats permettraient de proposer des voies de valorisation, de contrôle de qualité et de labellisation du fenouil beldi sous un signe distinctif d’origine et de qualité