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Abstract Fermentation of cereal-made dough was the primary Ethiopian food for many years. Sourdough is believed to have many beneficial fermenting micro-floras depending on the source of dough and environmental conditions. The study aimed to isolate and characterize yeasts from fermenting cereal dough and evaluate their leavening potential for wheat dough. Morphological and biochemical characterizations such as sugar fermentation, glucose tolerance test, growth at different pH and temperatures, and agitation effect were employed to select potent yeasts. Accordingly, 16 potential yeast isolates were selected and subjected to further analysis. Finally, the yeasts were tested and compared for their leavening activity on the wheat dough at 37 °C and room temperature. Results revealed marvelous CO2 producer mesophile yeasts that degrade various sugars and tolerate up to 60% glucose concentration. The overall characterization assigned all the yeast isolates to the genus Saccharomyces and the Candida humilis. ANOVA showed that leavening activity by the yeast isolates was statistically higher at 37 °C compared to room temperature. The highest dough volume (6.2 mL) was recorded from Wh17, Wh5, and Ba12 isolates. Sor9 isolates were among the yeast that raised a minimum dough volume (0.7 mL). In contrast to commercial yeasts, the present study detected exceptional yeasts that matured within 24 h. Therefore, the discovered potential yeasts can be used for leavening dough in a short fermentation time and add aroma to baked products, making them a candidate in the baking industry. It could also be cost-effective as it could reduce media consumption and electricity utilization.

This study was conducted to develop an efficient regeneration protocol used for sesame genetic transformation. Published regeneration methods using 6-benzylaminopurine (BAP), indol-3-butyric acid (IBA), and α-naphthaleneacetic acid (NAA) were used in this experiment. Cotyledon explants of 14 Ethiopian genotypes collected from Humera Agricultural Research Center (HuARC) were used. Optimized culture conditions were used to investigate the regeneration response of different genotypes. Significant interactions between hormone treatments, MS media, and genotypes for shoot and root regeneration were recorded. Results showed that culture of cotyledons were developed and used as a source of explants for shoot regeneration. The highest shoot number, leaf number, and shoot length were recorded on explants cultured on 1.00 mg·L−1 BAP + 1.00 mg·L−1 NAA in Hirhir and Aberghele, 0.75 mg·L−1 BAP + 1.00 mg·L−1 NAA in Baha Zeyit, and 1.0 mg·L−1 BAP + 1.00 mg·L−1 NAA in Humera 1, respectively. The lowest shoot number, leaf number, and shoot length were observed on explants cultured on the control in Gondar 1, Borkana, and Baha Necho, Borkana and Beha Necho, and Baha Necho, respectively. Genotypes with well-developed shoots were transferred to root induction media. Under rooting media, the best mean, root number, and root length were observed in Aberghele and ACC44 at 0.1 mg·L−1 IBA and 0.2 mg·L−1 NAA, respectively. Standardizing genotypes trait data to mean 0 and unity variance has helped to group 14 genotypes into four distinct clusters. Hirhir, Abeghele, Baha Zeyit, and Humera 1 were the best genotypes. These findings lay ground to Ethiopian sesame to do further genetic transformation aiming at improving the crop.