Abstract: Coffee has for centuries played an important role in the Ethiopian economy and represents the main cash crop cultivated by small-scale farmers for social, economic, political and ecological sustainability. The estimated coffee production area in Ethiopia is 561,761 ha. In Ethiopia, coffee berry disease (CBD), coffee wilt disease (CWD) and coffee leaf rust (CLR) are foremost factors in reducing the quantity and quality of coffee in the country. developing disease resistant landrace coffee varieties and boost the yield with their intrinsic cup quality, a multidisciplinary research program has been designed and implemented at Jimma agricultural research center. To meet this objectives, local land race development program of Tepi 88 coffee collections were started in 2015 and 108 coffee accessions were collected and planted in 2016 at Tepi and Gera research sub centre by Jimma Agricultural Research Center. so, 88 coffee accessions were evaluated for their resistance using visual assessment, attached berry test to CBD, visual to scores CLR and laboratory inoculation test to CWD. There were significant differences among the Tepi coffee collections tested for resistance to coffee berry disease. The range was from 0% (T-83/2011) – 98% (T-63/2011) most of Tepi coffee accessions show susceptable reaction for CBD but most of the accessions show resistance reaction at Gera. Coffee collections were also evaluated for their resistance to coffee leaf rust under field condition at Tepi research center. Highly significant difference among coffee cultivars in percent coffee leaf rust severity was observed (Table 1). Coffee leaf rust disease percent severity varied between 0.17% (T-41/2011) – 21.7% (T-11/2011). There existed highly significant difference among cultivars both in percent wilt seedlings death and incubation period). Disease severity and incubation period on Tepi coffee collections varied between 9.33% (T-06/2011) –97.3% (T-21/2011) and 132 -10 days respectively. Based on over all detailed analysis of field evaluation and greenhouse test investigation for major diseases, and their Yield potentials, Nine Tepi coffee accessions were promoted to Variety verification.Abstract: Coffee has for centuries played an important role in the Ethiopian economy and represents the main cash crop cultivated by small-scale farmers for social, economic, political and ecological sustainability. The estimated coffee production area in Ethiopia is 561,761 ha. In Ethiopia, coffee berry disease (CBD), coffee wilt disease (CWD) and coffee le...Show More
Abstract: The aim of this study is to prepare a novel precursor for the synthesis of imidazo[5,4- f]benzimidazole(imino)quinone. This will target the over-expression of the enzyme NAD(P)H: quinone oxidoreductase (NQO1) in solid tumours. An electron withdrawing group was incorporated into the structure, and the substituted ring size was reduced as this is hypothesised to increase its binding affinity to NQO1. The 2, 5-difluoroaniline was acetylated using acetic anhydride to produce N-(2,5-difluorophenyl) acetamide. The latter underwent selective nitration to produce N-(2,5-difluoro- 4-nitrophenyl) acetamide followed by oxidation using methane sulfonic acid and hydrogen peroxide to give 1,4-difluoro-2,5-dinitrobenzene. The synthesized precursor was achieved by the double nucleophilic aromatic substitution of morpholine and pyrrolidine onto 1,4-difluoro-2,5-dinitrobenzene. The 4-(2,5-dinitro-4-pyrrolid-1-yl) morpholine was successfully synthesized in four synthetic steps. The identity and purity were confirmed using NMR with peaks assigned using proton-fluorine coupling values. Further work is recommended for the developments of this study, additional synthetic steps using the novel precursor need to be carried out to achieve oxazino[4,3-a] pyrroloimidazo[5,4-f] benzimidazole(imino)quinone.Abstract: The aim of this study is to prepare a novel precursor for the synthesis of imidazo[5,4- f]benzimidazole(imino)quinone. This will target the over-expression of the enzyme NAD(P)H: quinone oxidoreductase (NQO1) in solid tumours. An electron withdrawing group was incorporated into the structure, and the substituted ring size was reduced as this is hyp...Show More
Abstract: When oxidation by free radicals exceeds antioxidant systems in the body, oxidative stress usually results. This is common in the underlying processes leading to aging, infertility and of a range of non-communicable diseases including cancers, cardiovascular diseases, neurodegenerative diseases and rheumatoid arthritis. There exist measures to curb oxidative stress, one of which is to take in exogenous antioxidants in form of supplements and in diet. Studies have shown that certain plants have antioxidant and free radical scavenging activity. The aim of this study is to evaluate the free radical scavenging activity (FRSA) of the crude extract of Platostoma africanum P. Beauv. (Lamiaceae). The crude extract was partitioned using N-hexane, Di-ethylether, Ethyl acetate and N-butanol in that order. TLC phytochemical screening as well as DPPH bioautographic analysis was done for each fraction as well as the residual aqueous fraction in suitable mobile phase system in order to evaluate their FRSA and secondary metabolites. A DPPH assay was then carried out using ultraviolet spectroscopy to quantify the activity. The fraction with the lowest IC50 and highest activity was further separated into fractions by column chromatography. DPPH bioautography and phytochemical screening were done on the resulting fractions. The crude as well as the five fractions had FRSA in varying degrees. Ethyl acetate fraction had the lowest IC50 (0.42mg/mL) and the highest activity. The decreasing order of activity was ethyl acetate>diethyl ether>n-butanol>crude>aqueous>n-hexane. Among the fractions obtained from column chromatography, fraction D was the most active. Terpenoids and flavonoids were the main secondary metabolites observed in the plant and were responsible for the FRSA. Platostoma africanum P. Beauv. has antioxidant activity which is mostly due to its terpenoid and flavonoid content.Abstract: When oxidation by free radicals exceeds antioxidant systems in the body, oxidative stress usually results. This is common in the underlying processes leading to aging, infertility and of a range of non-communicable diseases including cancers, cardiovascular diseases, neurodegenerative diseases and rheumatoid arthritis. There exist measures to curb ...Show More
