Antiplasmodial volatile extracts from Cleistopholis patens Engler & Diels and Uvariastrum pierreanum Engl. (Engl. & Diels) (Annonaceae) growing in Cameroon

In a search for alternative treatment for malaria, plant-derived essential oils extracted from the stem barks and leaves of Cleistopholis patens and Uvariastrum pierreanum (Annonaceae) were evaluated in vitro for antiplasmodial activity against the W2 strain of Plasmodium falciparum. The oils were obtained from 500 g each of stem barks and leaves, respectively, by hydrodistillation, using a Clevenger-type apparatus with the following yields: 0.23% and 0.19% for C. patens and 0.1% and 0.3% for U. pierreanum (w/w relative to dried material weight). Analysis of 10% (v/v) oil in hexane by gas chromatography and mass spectrometry identified only terpenoids in the oils, with over 81% sesquiterpene hydrocarbons in C. patens extracts and U. pierreanum stem bark oil, while the leaf oil from the latter species was found to contain a majority of monoterpenes. For C. patens, the major components were α-copaene, δ-cadinene, and germacrene D for the stem bark oil and β-caryophyllene, germacrene D, and germacrene B for the leaf oil. The stem bark oil of U. pierreanum was found to contain mainly β-bisabolene and α-bisabolol, while α- and β-pinenes were more abundant in the leaf extract. Concentrations of oils obtained by diluting 1-mg/mL stock solutions were tested against P. falciparum in culture. The oils were active, with IC50 values of 9.19 and 15.19 μg/mL for the stem bark and leaf oils, respectively, of C. patens and 6.08 and 13.96 μg/mL, respectively, for those from U. pierreanum. These results indicate that essential oils may offer a promising alternative for the development of new antimalarials

Comparative essential oils composition and insecticidal effect of different tissues of Piper capense L., Piper guineense Schum. et Thonn., Piper nigrum L. and Piper umbellatum L. grown in Cameroon

This study compared the chemical composition of the essential oils obtained by hydrodistillation of different tissues of Piper capense, Piper guineense, Piper nigrum and Piper umbellatum grown in Cameroon. The GC and GC/MS analysis showed qualitative and quantitative differences between these oils. Oils from the fruits were rich in a-pinene (5.6 - 12.3%) and b-pinene (6.7 - 59.3%). The other major constituents were sabinene (14.7%) for P. capense, limonene (15.8%) and b-caryophyllene (20.8%) for P. guineense. The oil from the fruits of P. nigrum contained sabinene (11.2%), d-3-carene (18.5%),limonene (14.7%) and b-caryophyllene (12.8%) while that of P. umbellatum content linalool (14.4%) and (E)-nerolidol (10.0%) as major constituents. The essential oil obtained from the leaves of P. capense was largely composed of a-pinene (12.8%), -pinene (50.1%) and b-caryophyllene (12.4%). The most abundant constituents identified in the oil from the leaves of P. guineense were limonene (10.3%) and germacrene B (25.1%) while that from P. nigrum was characterized by its high amount of a-selinene (16.5%) and -selinene (14.6%). -pinene (10.8%), -caryophyllene (28.2%) and (E)-nerolidol (16.5%) were the quantitative important constituents of the essential oils from the leaves of P. umbellatum. Theoils from the lianas of P. guineense was rich in (Z, E)-a-farnesene (28.7%), limonene (19.7%) and myristicine (10.9%), while those from P. nigrum contained d-3-carene (14.4%) and -caryophyllene(36.0%). The oil from the stems of P. capense contained mostly a-pinene (14.3%) and -pinene (61.4%). The distillation of those from P. umbellatum did not produce any essential oil. Oils from the three fruits showed variable contact toxicity against Sitophilus zeamais with P. guineense being more toxic (LD50 =10.0 ± 0.3 ìl/g) than P. capense (LD50 = 16.1 ± 0.6 ìl/g) and P. nigrum (LD50 = 26.4 ± 1.5 ìl/g). Poudrox (5%) used as a standard insecticide exhibited 100% mortality

Proximate composition, mineral content and fatty acid profile of two marine fishes from Cameroonian coast: Pseudotolithus typus (Bleeker, 1863) and Pseudotolithus elongatus (Bowdich, 1825)

Background: Knowledge of chemical composition of fish from Cameroon is poor. The genera Pseudotolithus are nutritionally and economically important in Cameroon. Thus the knowledge on their chemical composition could help in functional food elaboration. Purpose: In this study, Proximate composition, fatty acid profiles and mineral composition were determined in two fish species, Pseudotolithus typus and Pseudotolithus elongatus from Cameroonian coasts. Basic procedure: AOAC standard method was used. Fatty acids were identified by GC/MS as N-acylpyrolidides. Mineral compositions were determined by atomic absorption spectrophotometry for Ca, Na, K, Mg, Fe, Zn, Cu, Mn, and by UV spectrophotometry for phosphorus (P). Main finding: Results indicated that chemical composition was not similar in the two fish species. Results also showed that water is the main constituent in the edible parts and in the bones with 76.17% to 78.24% and 51.21% to 55.28% respectively. Pseudotolithus typus and Pseudotolithus elongatus were good sources of proteins with 16.17% and 13.4% respectively. All the fish analyzed for fat were lean with fat contents less than 0.5%. These species of fish were poor in ω6PUFA and were rich in ω3PUFA with about one third of total fatty acids. The main ω3 fatty acids were eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The most abundant main elements were the potassium in the edible parts (1.39%) and calcium in the bones (18.26%). The most abundant trace elements were Zn and Fe in the edible parts and in the bones. Principal conclusion: The Na/K ratio values and ω3 fatty acids contents suggest that consumption of these two fish species could be recommended to prevent cardiovascular diseases. Keywords: Proximal composition, Mineral content, Fatty acid profiles, Pseudotolithus typus, Pseudotolithus elongate

Molecular markerbased genetic linkage map of a diploid banana population (Musa acuminata Colla)

A well-saturated genetic linkage map is valuable for fundamental and applied genetic research. Genetic linkage maps of two half-sib diploid banana populations were constructed using allele-specific-polymerase chain reactions (AS-PCRs), diversity array technology (DArT), and simple sequence repeat (SSR) markers. Molecular maps were produced for each parent using the pseudo-testcross mapping strategy. The first maternal map (6142-1, 81 individuals) consisted of 231 markers divided as followed: 121 DArT, 106 SSR and 4 AS-PCR markers in 15 linkage groups (LGs) covering 670 cM. The second maternal map (6142-1-S, 58 individuals) contained a total of 152 markers including 71 DArTs, 79 SSRs, and 2 AS-PCRs mapped to 16 LGs that spanned 698 cM. The combined paternal map (139 individuals) comprised 316 markers (196 DArTs, 117 SSRs and 3 AS-PCRs) distributed over 15 LGs with a total map length of 1,004 cM. While distorted segregation of some markers was observed in all maps, this was much more frequent for the male parent. Homology between maps was assessed using common markers. While there was generally good congruity with regard to marker order across maps, incongruity in other cases may reflect chromosomal rearrangement events such as inversions, translocations, or deletions. The new banana map can provide a better understanding of the Musa genome and could be used for the identification of economically important traits and improvement of breeding strategies

Composition of four essential oils obtained from plants from Cameroon, and their bactericidal and bacteriostatic activity against Listeria monocytogenes, Salmonella enteritidis and Staphylococcus aureus

The composition of four essential oils (EOs) extracted by hydrodistillation from plants of common use in Cameroon (Curcuma longa, Xylopia aethiopica, Zanthoxylum leprieurii L., Zanthoxylum xanthoxyloides) was assessed by gas chromatography-mass. Their bactericidal and bacteriostatic activity was tested in vitro against three food borne pathogenic bacteria: Listeria monocytogenes, Salmonella enteritidis and Staphylococcus aureus. The bacteriostatic activities of this EOs on food borne bacteria were assessed in vitro through optical density measurements. The minimal bactericidal concentrations (MBC) were determined in broth combined with a spot plating method. Z. xanthoxyloides and Z. leprieurii showed a similar composition, with a prevalence of oxygenated monoterpenes (about 58%). The EO of Z. xanthoxyloides was the most effective against the microorganisms tested. Its higher concentration of geraniol could be linked to this higher activity. In almost all cases, the MBC was higher than the maximum concentration tested (3000 ppm). Notwithstanding their low bactericidal effect, the EOs studied showed interesting inhibiting activities against the tested food borne pathogens. S. enteritidis was the most resistant to the bacteriostatic effect of the four EOs. The knowledge of the antimicrobial potential of local plant EOs used in developing countries could help in their choice and their use to improve food safety and shelf-life