The objective of this paper is to present the beneficial aspects of some insects consumed in sub-Saharan Africa, based on examples of insects consumed in Cameroon, to present their potential as sources of lipids and essential fatty acids. In Africa, termites, larvae of raphia weevil, caterpillars, crickets, bees, maggots, butterflies, weevil, etc. are significant sources of food. These insects belong mainly to the orders of : Isoptera, Orthoptera, Dictyoptera, Coleoptera, Hymenoptera, Lepidoptera and Diptera. Depending on the species, insects are rich in proteins, minerals (K, Ca, Mg, Zn, P, Fe) and/or vitamins (thiamine/B1, riboflavine/B2, pyridoxine/B6, acid pantothenic, niacin). The composition of oils extracted from the following six insects consumed in Cameroon was investigated : larvaes of raphia weevil (Rhynchophorus phoenicis), crickets (Homorocoryphus nitidulus), grasshopper (Zonocerus variegates), termites (Macrotermes sp.), a variety of caterpillars (Imbrasia sp.) and an unidentified caterpillar from the forest (UI carterpillar). The extraction yields of oil were 53.75%, 67.25%, 9.12%, 49.35%, 24.44% and 20.17% respectively for raphia weevil larvae, crickets, devastating crickets, termites, Imbrasia and UI caterpillar. The oil from raphia weevil mainly contains 37.60% of palmitoleic acid and 45.46% of linoleic acid. The oil from crickets is principally made up of palmitoleic acid (27.59%), linoleic acid (45.63%) and α-linolenic acid (16.19%). The oil from grasshoppers is composed of palmitoleic acid (23.83%), oleic acid (10.71%), linoleic acid (21.07%), α-linolenic acid (14.76%) and γ-linolenic acid (22.54%). The main components of termite oil are : palmitic acid (30.47%), oleic acid (47.52%) and linoleic acid (8.79%). Palmitic acid (36.08%) and linolenic acid (38.01%) are the two dominant fatty acids of Imbrasia oil. As Imbrasia oil, UI caterpillar oil is composed of palmitic acid (30.80%) and linolenic acid (41.79%). Stearic acid (7.04%), oleic acid (8.56%) and linoleic acid (6.59%) are also present. These results show that these insects are considerable sources of fat. Their oils are rich in polyunsaturated fatty acids, of which essential fatty acids are linoleic and linolenic acids. The ratio PUFA/SFA, in the majority of cases is higher than 0.8, associated with desirable levels of cholesterol

Lipid oxidation is responsible for the deterioration of the nutritional and organoleptic qualities of foods. It also leads to the formation in these products of compounds which are harmful for the consumer's health. The synthetic antioxidants used by industries in order to solve this problem are also prone to be toxic and quite volatile at high temperatures. On the other hand, the trend among researchers to replace the synthetic antioxidants with natural ones is increasing because of their potential health benefits. In this study, old Cameroonian green tea leaf methanolic extracts were added in palm olein and its efficiency in delaying the oxidation of oil under forced storage conditions was assessed. The plant material was extracted with methanol and its total phenolics content evaluated by colorimetry, followed by the qualitative identification of some phenolic antioxidants by HPLC-DAD and ESI-MS. After preliminary antioxidant studies, the extract was added in oil at concentrations that ranged from 200 to 1800 ppm. Oil containing butylated hydroxytoluene (BHT) and oil without antioxidant served as positive and negative controls, respectively. The oxidative stability of these oil samples was evaluated by determining their oxidation induction times on Rancimat (at 110 °C) and measuring their oxidative state by the Schaal oven test method during 30 days of storage at 70 °C. Here, oil samples were collected every 10 days and their peroxide, p-anisidine, total oxidation, thiobarbituric acid, iodine values as well as changes in their linoleic acid profile gas chromatography coupled to flame ionization detector (GC/FID) were evaluated. The outcomes showed the total phenolics content of the extract to be 53.5 mg GAE/g. Gallic acid, epicatechin gallate, gallocatechin and epigallocatechin gallate were the phenolic antioxidants detected. The induction times of palm olein supplemented with the extract (200–1800 ppm) were found to be in the range of 24.8–28.9 h, while those of control and oil containing BHT were 20.1 and 22.7 h, respectively. The extracts, at all concentrations, were also found to be efficient like butylated hydroxytoluene in inhibiting the oxidation of palm olein during 30 days of storage at 70 °C. The investigations showed that old Cameroonian green tea leaves are a viable source of natural antioxidants for delaying palm olein oxidation.

Essential oils are complex mixtures of volatile components produced by the plant secondary metabolism and consist mainly of monoterpenes and sesquiterpenes and, to a minor extent, of aromatic and aliphatic compounds. They are exploited in several fields such as perfumery, food, pharmaceutics, and cosmetics. Essential oils have long-standing uses in the treatment of infectious diseases and parasitosis in humans and animals. In this regard, their therapeutic potential against human African trypanosomiasis (HAT) has not been fully explored. In the present work, we have selected six medicinal and aromatic plants (Azadirachta indica, Aframomum melegueta, Aframomum daniellii, Clausena anisata, Dichrostachys cinerea, and Echinops giganteus) traditionally used in Cameroon to treat several disorders, including infections and parasitic diseases, and evaluated the activity of their essential oils against Trypanosma brucei TC221. Their selectivity was also determined with Balb/3T3 (mouse embryonic fibroblast cell line) cells as a reference. The results showed that the essential oils from A. indica, A. daniellii, and E. giganteus were the most active ones, with half maximal inhibitory concentration (IC₅₀) values of 15.21, 7.65, and 10.50 µg/mL, respectively. These essential oils were characterized by different chemical compounds such as sesquiterpene hydrocarbons, monoterpene hydrocarbons, and oxygenated sesquiterpenes. Some of their main components were assayed as well on T. brucei TC221, and their effects were linked to those of essential oils.