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Background: For many years, ganoderma was highly considered as biofactory for the production of different types of bioactive metabolites. Of these bioactive compounds, polysaccharides gained many attentions based on their high biotherapeutic properties. Therefore, special attention have been paid during the last years for production of mushrooms bioactive compounds in closed cultivation system to shorten the cultivation time and increase the product yield. Results and Discussion: Therefore, this work is focused on the development of simple cultivation system for exopolysaccharides (EPS) production using Ganoderman lucidum. At first, the best medium supporting EPS production was chosen experimentally from the current published data. Second, like many EPS production process, carbon and nitrogen concentrations were optimized to support the highest production of polysaccharides in shake flask level. Furthermore, the process was scaled up in 16-L stirred tank bioreactor. The results clearly demonstrated that the best cultivation strategy was cultivation under controlled pH condition (pH 5.5). Under this condition the maximal volumetric and specific yield of EPS production were, 5.0 g/L and 0.42 g/g, respectively. Conclusion: The current results clearly demonstrates the high potential use of submerged cultivation system as alternative to conventional solid state fermentation for EPS production by G. lucidum. Furthermore, optimization of both carbon and nitrogen sources concentration and scaling up of the process showed significant increase in both volumetric and specific EPS production.

Citric acid is an essential ingredient for the manufacture of (12) key industrial chemicals. Citric acid use is increasing steadily with a high annual growth rate as a result of the development of ever more sophisticated applications. Citric acid is widely utilized in the food and pharmaceutical industries due to its low toxicity when compared to other acidulous. Other uses for citric acid can be found in cleaning supplies and detergents. Based on information from a review of the literature, Citric acid production substrates and methods for surface fermentation, submerged fermentation, solid-state fermentation, and international market expansion are all covered in the current review study. Finally, there is still much to learn about the circumstances of the production of citric acid from raw materials, microorganisms, and fermentation techniques to achieve the best production in terms of cost and quality.

Background: The succinic acid demand accelerated through the years. Thus, the need to improve acid production economically is aggravated. The fermentation process by succinate bacteria showed promising acid production. However, due to different bacteria characteristics, mediums composition and operating conditions, a fixed quantity of succinic acid production cannot be determined or generalized. Recently, raising interest in examining cheap mediums in the fermentation process brought attention to utilizing different raw materials. Nevertheless, its influence on production is not fully comprehended. Methods: This research aims to develop an evaluation of three succinate bacteria on succinic acid production. Also, it aims to demonstrate a comparative analysis of the Succinic acid production by three raw carbon sources (Corn fiber, Cane molasses and orange peel). The flask batch method and the 4-L Bioreactor were employed in the evaluation. Result: The results of the study showed that the Actinobacillus succinogenes is the best succinate bacteria to provide commercial Succinic acid. The presence of 10 g of glucose was satisfactory in improving the fermentation among all bacteria. The highest Succinic acid production was 12.8 g/L provided by the corn fiber. The lowest succinic acid production was 18% less than the glucose medium that the orange peel gave. The results revealed a significant impact of the raw material composition on the production outcomes. At the bioreactor, the cells exhibited an exponential phase with rate growth of 0.175 [g/L.h] and the maximum Succinic acid produced was 25 g/L.