PERSISTENCE OF ACTIVE COMPOUNDS OF ESSENTIAL OILS OF CLAUSENA ANISATA (RUTACEAE) AND PLECTRANTHUS GLANDULOSUS (LABIATEAE) USED AS INSECTICIDES ON MAIZE GRAINS AND FLOUR

ABSTRACT Maize occupies an important place in the resolution of food insecurity problems in the sub-Saharan region of Africa. However due to poor post-harvest technologies, more than 35% of annual crop yield is often lost during storage as a consequence of insect attack. While chemical pesticides constitute an efficient tool for reducing these losses, current excessive usage runs the risk of modifying the quality and safety of foods produced from these grains. The use of essential oils of plant origin for grain storage has been advocated as a non invasive method with limited or no effect on the quality and safety of the grains or their products. This study was carried out as an evidence of bioactivity of two essential oils of Clausena anisata (Willd.) Hook and Plectranthus glandulosus Hook F. against adults of Tribolium castaneum Herbst and Sitophilus zeamais Motschulsky, which are two important stored product insect pests in Northern Cameroon. Because of the low persistence of the insecticidal activities of these plants, their essential oils to achieve a complete protection of the stored products must be applied at frequent delays. The present investigation focuses on the occurrence of residues of these oils on treated maize grain and flour. The doses of crude essential oils used to treat adults of S. zeamais and T. castaneum in a contact and inhalation process were their LD 99 s. After the evaluation of their insecticidal activity the persistence of each essential oil was observed every 2 days till 14 days. After the disappearance of their insecticidal activities, essential oil was re-extracted and their residual compounds were identified from treated grain and flour. The major compounds of C. anisata are, estragole, α-humulene, germacrene D and (E)-nerolidol. In P. glandulosus they are: fenchone, α-terpinolene and piperitenone oxide. After 14 days, only 64.24% of compounds of C. anisata were recovered on treated flour and 55.16% on grains. Concerning P. glandulosus, 48.94% was recovered on grains and 61.23% on flour

Evaluation nutritionnelle de quelques ingrédients entrant dans la formulation alimentaire des poules pondeuses et porcs d’une ferme d’élevage au Nord- Ouest Cameroun

Les provendes constituent la principale composante de dépense en aviculture et en élevage porcin. On constate sur le marché une différence de prix pour un même ingrédient donné, livré par des fournisseurs. Ainsi, dans l’optique d’orienter les fermiers pour le choix des ingrédients de hautes valeurs nutritionnelles et de moindre coût, le présent travail a pour objectif d’établir une base de données des valeurs nutritionnelles de quelques ingrédients (tourteaux de soja, farine de poisson, balles de riz, tourteau d’arachide et aliment ponte) entrant dans la formulation alimentaire des poules pondeuses et porcs. Ainsi, les différents échantillons ont été collectés auprès des fournisseurs et les aliquotes ont été prélevés pour les analyses au laboratoire. Les teneurs en eau, cendres, protéines et lipides ont été déterminées selon les méthodes AOAC. La teneur en glucide a été déterminée par différence. A l’issue de ces analyses, il ressort que les teneurs exprimées en g/100g se trouvent dans les fourchettes suivantes : eau 8,86-16,65; cendres 3,93-18,98 ; protéines 5,51-63,73 ; lipides 8,53-26,96 ; glucide, 0,0-61,18 et énergie 341,23-465,54 kcal/100g. Ces données pourraient orienter les fermiers pour le choix des ingrédients de hautes valeurs nutritionnelles et de moindre coût.Mots clés : Valeur nutritionnelle, ingrédients, poules pondeuse, porcs

Diversity of processes for transformation of fresh fish in Northern Cameroon

Fish as a foodstuff of high nutritional value is considerably perishable. It must be transformed in order to improve the duration of its conservation. Drying and smoking are the most popular processes to transform fish in northern Cameroon. These steps usually affect the quality of the finished products. In order to improve the quality of locally transformed fish in a handmade manner and to typify such activity, an survey was conducted in three fishing ponds in the Northern part of Cameroon with 160 fishermen and fish transformers. It appears that the technique of transforming fish in those main fishing ponds in Northern Cameroon vary at the level of preprocessing and dehydration phases of fresh fish. Smoking is done in a traditional oven followed by cleaning (4.1% in the Adamawa Region and 33.0% in the North and Far North Region) or flaking of the fish (95.9% in Adamawa and 61.1% in the North and the Far North Region). Then, come emptying (95.9% in Adamawa and 61.1% in the North and Far North), cutting into small pieces (11.1% in the Far North) or cracking (82.6% in the Adamawa Region). At the end, washing (95.9% in the Adamawa and 72.2% in the North and Far North), spinning (100%), smoking (100%) and then packaging of the fish (100%) complete the process. All these operations are conducted without equipment for protection, on uncleaned surfaces and with irregularly washed materials with clean water. The drying process is done on bare ground on top of a drying stall is a constant step in the Far North (54.9%) and North (28.6%) regions and scarce in the Adamawa region (9.3%). A particular emphasis should be laid on hygienic measures to ensure a sanitary quality of dry fish at the end of both smoking and drying processes. Keywords: Processing, smoking, drying, Northern Cameroon, Transformatio

Effet de la supplémentation du Pennisetum purpureum au concentré riche en protéines sur les performances de croissance des cobayes (Cavia porcellus L. 1758) femelles à l'Ouest Cameroun

The effect of supplementation of Pennisetum purpureum (Pp) to protein concentrate (PB) on the growth performance Cavia porcellus (L. 1758) was evaluated for 2 months at the application and Research of the University of Dschang (West-Cameroon). 16 guinea-pigs with a average weight of 281 ± 42.0 g were used randomly in four treatments T0 (Pp), T1 (Pp + 16 % PB), T2 (Pp + 17 % PB) and T3 (Pp + 18 % PB). Chemical analysis showed that the different food formulations are rich in protein (16 to 18%), crude fiber (10%), metabolizable energy (2827 to 2857 Kcal/KgMS), calcium (0.95 %) and phosphorus (0.58 %). Results of the growth parameters showed that mean weights of animals increased significantly (P <0.05) between treatments. Food consumption increased with the age of animals. Guinea-pigs of the control batch T0 (8704.5 ± 0.00 g) consumed more than those of other treatments. The average daily gain varied significantly (P <0.05) between treatments. The consumption index is high for animals of the T0 batch (96.2 ± 7.80) as against 66.8 ± 35.6; 52.3 ± 14.3; 60.4 ± 22.4 respectively for batches T1, T2 and T3. The treatment T1 was the best ration. Keywords: Cavia porcellus, growth, Pennisetum purpureum, proteins, West Cameroon.L’effet de la supplémentation du Pennisetum purpureum (P.p) au concentré riche en protéines brutes (PB) sur les performances de croissance Cavia porcellus (L. 1758) femelles a été évalué durant 2 mois à la ferme d’application et de recherche de l’Université de Dschang (Ouest-Cameroun). 16 cobayes de poids moyen 281± 42,0 g ont été utilisés et répartis de manière aléatoire en quatre traitements T0 (P.p), T1 (P.p + 16 % PB), T2 (P.p + 17 % PB) et T3 (P.p + 18 % PB). L’analyse chimique montre que les différentes formulations alimentaires sont riches en protéines (16 à 18 %), en cellulose brute (10 %), en énergie métabolisable (2827 à 2857 Kcal/Kg MS), en calcium (0,95 %) et en phosphore (0,58 %). Les résultats de paramètres de croissance ont montré que les poids moyens des animaux ont connu une augmentation significative (P < 0,05) entre les traitements. La consommation alimentaire a augmenté avec l’âge des animaux. Les cobayes du lot T0 (8704,5 ± 0,0 g) ont le plus consommé par rapport aux autres traitements. Le gain moyen quotidien a varié significativement (P<0,05) entre les traitements. L’indice de consommation est élevé chez T0 (96,2 ± 7,80) contre 66,8 ± 35,6; 52,3 ± 14,3 et 60,4 ± 22,4 respectivement pour T1, T2 et T3. Le traitement T1 est la meilleure ration. Mots clés: Cavia porcellus, croissance, Pennisetum purpureum, protéines, Ouest Cameroun. &nbsp

Pratiques Paysannes De Production Durable Des Graines De Voandzou [Vigna Subterranea (L.) Verdc.] Pour La Sécurité Alimentaire Dans Le Cameroun Septentrional

Bambara groundnut is a leguminous plant with high nutritive value of Sub Saharan Africa. In spite of its high potential in alimentation, the Bambara groundnut is less popularized. This crop grows on acid, dry and less fertile soils and may therefore be a resilient crop in the context of climatic variability. The present work aims to identify of all the morphotypes of this culture and the usual tools of conservation of its seeds during the storage process. Investigations carried out during 3 agricultural campaigns showed that women more than 40 years old represents more than 98% of producers of Bambara groundnuts in northern Cameroon. The production concerns 54 morphotypes use as food or as medicinal plants. During storage of grains of this legumes, the major pest is the bruchid Callosobruchus maculatus Fab. (Coleoptera : Chrysomelidae). Under traditional production way, the limitation of the postharvest losses due to this pest is done either by the use of 21 local plants as botanical insecticide or by the use of 25 industrial chemical pesticides

Susceptibility of three varieties of Bambara groundnut (Vigna subterranea L.) towards Callosobruchus maculatus according to their nutritional and antinutrient contents

The leguminous seeds of voandzou (Vigna subterranea L.) are an important source of protein and anti-nutrients. The present study analyses nutritional and antinutrients content of 3 varieties of voandzou during storage under attacked by Callosobruchus maculatus. Three varieties of voandzou seeds with distinct colors: white cream (CM/EN/DW/14), red (CM/EN/DW/07) and black (CM/EN/DW/28) were collected from local markets and stored in flasks for 3 months. Thereafter, these seeds were sieved and weighted per batch. Chemical analysis of nutritional potential according AOAC methods and Phytic acid, Tannin, Oxalate and the trypsin inhibition activity were conducted both on clean and infested voandzou seed samples. The results showed that the CM/EN/DW/14 seed variety was the most attacked (75.4%) followed by CM/EN/DW/07 (42.6%). Nutritional properties indicate that CM/EN/DW/14 had the highest nutrient contents, highest ash and moisture content, while CM/EN/DW/28 recorded the lowest nutritional content compared to the other two samples. Concentrations of studied anti-nutritional factors were significantly different according to the color. The black color has the highest concentration of anti-nutrients content compared to the red and the white cream color. Seeds with higher anti-nutrients content had less attack rates compared to the others. Keywords: Voandzou, Callosobruchus maculatus, Antinutient contents, Storage abilit

Variation of some chemical and functional properties of Bambara groundnut (Voandzeia Subterranean L. Thouars) during sort time storage

Abstract The storage susceptibility of Bambara groundnut (B. G.) (Voandzeia Subterranean (L.) Thouars) to Callosobruchus maculatus and chemical and functional properties of 11 varieties form Far-North of Cameroon were investigate using standard analytical methods. Storage susceptibility shown that, after five months within treatment, C. maculatus destroy 10 to 50% of grains. The chemical characteristics of none attack grains of 11 varieties were range to 18.64 at 21.08%, 6.85 at 7.44%, 49.75 at 52.68% and to 6.05 at 7.55% respectively for protein, fat, starch and free carbohydrate. These chemical characteristics significantly (p < 0.05) decreases form attacks varieties. For the functional parameters, the none attacks grains was range of 130 at 135%, 19.15 at 20.91%, 18.20 at 21.13%, 2.76 at 3.21% and of 8.54 at 10.14% respectively for water capacity absorption, solubility index, gel length, ash and humidity. The results of this study indicated that storage susceptibility, chemical and functional properties of B. G. be dependant to the varieties