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Three Schiff bases L 1 , L 2 and L 3 were synthesized by condensing salicylaldehyde with 4-aminoantipyrine, ethylendiamine and 2-aminophenol respectively and subsequently characterized by various physicochemical investigations.All the three compounds were screened for their In-vitro antibacterial activity against two gram positive bacteria, Staphylococcus aureus (S.A), Staphylococcus epidermidis (S.E) and two gram negative bacteria Klebsiella pneumoniae (K.P) and Pseudomonas aeruginosa (P.A) by agar diffusion method. On comparing the results obtained with the activity of commercially available antibiotics such as Ciprofloxacin and Chloramphenicol, the newly synthesized compounds showed comparable antibacterial activities. The solvent methanol exhibit activity against all bacterial species with IZs ranging from 8 ± 0.25 to 17 ± 0.29 mm while the standard antibiotics Ciprofloxacin and Chloramphenicol exhibited an activities with IZs varying from 21.3 ± 0.31 to 28.3 ± 0.32 and 26.3 ± 0.24 mm to 32.3 ± 0.23 mm, respectively. However, the newly synthesized Schiff bases L 1 , L 2 and L 3 showed IZs ranging from 7.4 ± 0.23 to 32.5 ± 0.14, 3 ± 0.57 to 12 ± 0.28 and 10 ± 0.20 to 32 ± 0.36 respectively. Among the Schiff bases, L 3 showed the activity (32 ± 0.36) against S.E and P.A which is higher than the activity of standard antibiotics Ciprofloxacin and Chloramphenicol against the same bacterial strains. The results obtained revealed that all the synthesized Schiff bases exhibit appreciable antibacterial activity against all the bacteria species which potentially makes them, to apply as wide range antibacterial drugs, after further in-vivo cytotoxicity investigations. Their activity can also be further modified by changing the functionali-

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Ten plant species, Cuminum cyminum seed, Foeniculum vulgare seed, Trachyspermum ammi seed, Nigella sativa seed, Coriandrum sativum seed, Aframomum corrorima fruit, Zingiber officinale rhizome, Cinnamomum aromaticum bark, Rosemary officinalis leaf and stem, and Thymus schimperi leaf, which are traditionally used as spices in Ethiopia were hydrodistilled to isolate their volatile constituents in order to identify their character-impact odorants. These spices comprise of 4%, 5.5%, 4%, 0.8%, 0.3%, 2%, 1%, 0.5%, 1.2% and 0.7% essential oil by mass. The GC-MS analysis of these essential oils obtained from these ten species led to the identification of 64 compounds. Twenty-three formulations were developed, of which 16 were from powdered spices to flavor bread (food) while the remaining seven were obtained from essential oil for flavoring bread and local areki (beverage). The flavor characteristics of these formulated samples were investigated by using GC-MSD and descriptive sensory analysis techniques. The key aroma impact compounds in each flavor were detected and the ultimate customer sensory taste of the products was determined for all samples. Results from the organoleptic evaluations of bread samples showed that the flavors prepared by adding essential oils of Foeniculum vulgare, Cuminum cyminum, Aframomum corrorima, Nigella sativa, and Trachyspermum ammi after fermentation had highest overall acceptability. Furthermore, local areki comprising of formulas developed from oil samples obtained from Foeniculum vulgare and Coriandrum sativum had better overall acceptability.

The world demand for paper has been increased due to the increasing population Therefore, to cop up the limited wood fiber resources introducing raw material in pulp and paper industries is necessary. The aims of this study to evaluate the pulp and paper-making properties of Caesalpinia decapetela based on proximate chemical composition, fiber morphology, pulping, bleaching, and physical test of the final product. The results proximate chemical analysis showed that C. decapetela has holocellulose content of 78.14±0.1 % and lignin content 18.0±0.04 %. Fiber morphology revealed that the fibers were 0.708 mm long, 18.63 μm width, and have 5.1 μm cell wall thicknesses. Kraft pulping of C. decapetale, was performed at different active alkali (5 %, 10 %, 15 %, 20 % and 25 %) and temperature (150, 160 and 170 °C), keeping the sulphidity 25 % constant. The pulp maximum yield 44.1 % was obtained at active alkali content of 15 %, temperature 160 °C, and cooking time 90 minutes. The effect of pulping on fiber morphology was studied using scanning electron microscopy which showed the surface of fiber before pulping was tight, orderly arranged and the texture was relatively hard. After pulping, there was the removal of lignin, hemicellulose, and cellulose. Due to this fiber become soft loosened and contain micro-pores. Pulp produced was bleached, sheet preparation and testing were performed. The prepared paper sheets have a tensile index of 28.19 Nm/gm, burst index of 1.359 kPa m 2 / gm 1.359\hspace{0.1667em}\text{kPa}\hspace{0.1667em}{\text{m}^{2}}/\text{gm} , and tear indices of 4.2 mN m 2 / gm 4.2\hspace{0.1667em}\text{mN}\hspace{0.1667em}{\text{m}^{2}}/\text{gm} . This study concluded C. decapetale can be the new raw material for pulp and paper making industries. However, pilot plant studies are required to check this raw material for the full recommendation of the pulp and paper industries.