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Artemisia spp are one of the most important traditional medicinal plants of Ethiopia which are used for the treatment of infection and non-infection health problems. The genus Artemisia (Astraceae) consists of about 500 species worldwide. Previous reports indicated that the different species of Artemisia have a wide array of biological activities including antimalarial, cytotoxic, antihepatotoxic, antibacterial, antifungal and antioxidant activity. In this study, the main aim was to investigate chemical components of Artemisia spp. (A. abyssinica, A. absinthium and A. annua) and evaluate their antimicrobial activities against bacterial strains. The results indicated that the crude extract of these plants were effective against some selected strains of bacterial strains. Here we isolated the well-known antimalarial drug artemisinin (7 mg, 0.004%) from Artemisia annua leaves using a rapid n-hexane fractionation method. The n-hexane extract of A. abyssinica, ethyl acetate extract of A. absinthium and n-hexane of A. annua showed varying degrees of inhibiting effect against bacterial strains such as Staphylococcus aureus ATCC 25923T, Salmonella enteritidis ATCC13076T, Klebsiella pneumoniae ATCC1053T, boydii ATCC1233T, Escherichia coli ATCC 25922T, hospital acquired Acinetobacter baumannii. The ethyl acetate extract of Artemisia absinthium (A.abe) showed the maximum inhibiting effect (35 mm) against A. baumannii. The minimum zone of inhibition (< 3 mm) was recorded for test extract of A.ap against Klebsiella pneumoniae ATCC1053T. Ethyl acetate extract of Artemisia absinthium (A.abe) was more effective against these selected bacterial strains and the zone of inhibition ranged from 5-35 mm. The minimum inhibition zone (8 mm) was detected against S. typhimurium ATCC 13311T for both A.ac and n-hexane- EtOAc fraction (8:2) of Artemisia abyssinica. The maximum zone of inhibition (25 mm) for fraction (A.ach F4) of Artemisia abyssinica obtained by column chromatography was recorded against S. pyogen ATCC 19615. However, there was no zone of inhibition detected for boydii ATCC1233T due to these test extracts. Significant variations (P = 0.887) were observed between all test extracts of these medicinal plants at 95% of confidence intervals. There is no zone of inhibition or growth for negative control. But, clear zones of inhibition were detected for positive control due to some standard impregnated disks. Based on our results we recommend that various species of Artemisia seem to have great potential for in-depth investigation for various antimicrobial activities that assists the effort in searching for antimicrobial lead compounds.

Nowadays the conventional plastic wastes are very challenging to environments and its production cost also creates an economic crisis due to petrochemical-based plastic. In order to solve this problem, the current studies were aimed at screening and characterizing these PHA producing isolates and evaluating the suitability of some carbon source for newly screened PHA producing isolates. Some carbon sources such as D-fructose, glucose, molasses, D-ribose and sucrose were evaluated for PHA production. Data were analyzed using SPSS version 20. The 16SrRNA gene sequence of these isolates was performed. This newly isolated taxa was related to Bacillus species. It was designed as Bacillus sp. LPPI-18 and affiliated Bacillus cereus ATCC 14577T (AE01687) (99.10%). Paenibacillus sp. 172 (AF273740.1) was used as an out-group. Bacillus sp. LPPI-18 is a gram-positive, rod-shaped, endospore former, and citrate test positive. This isolate showed positive for amylase, catalase, pectinase, and protease test. They produced intracellular PHA granules when this isolate was stained with Sudan Black B (SBB) and Nile Blue A (NBA) preliminary and specific staining dyes, respectively. Both Temperature and pH used to affect PHA productivity. Bacteria are able to reserve PHA in the form of granules during stress conditions. This isolate produces only when supplied with carbon sources. More PHA contents (PCs) were obtained from glucose, molasses, and D-fructose. In this regard, the maximum mean value of PC was obtained from glucose (40.55±0.7%) and the minimum was obtained from D-Ribose (12.4±1.4%). Great variations (p≤0.05) of PCs were observed among glucose & sucrose, molasses & sucrose and D-fructose & sucrose carbon sources for PHA productivity (PP) of Cell Dry Weight (CDW) g/L. After extraction, PHA film was produced for this typical isolate using glucose as a sole carbon source. Fourier transform infrared spectrum was performed for this isolate and showed the feature of polyester at 1719.64 to 1721.16 wavelength for these extracted samples. The peak of fingerprinting (band of carboxylic acid group) at this wave-length is a characteristic feature of PHB and corresponds to the ester functional group (C=O).