Addition of Vegetable Oil to Improve Triterpenoids Production in Liquid Fermentation of Medicinal Fungus Antrodia cinnamomea

The liquid fermentation of Antrodia cinnamomea is a promising alternative source for fungus production compared to the wildly grown fruiting body. Elicitation is a strong tool to enhance the productivity in microbial cells to obtain more compounds of interest. In this study, in order to improve the fungus growth and its terpenoids production, various vegetable oils were added in the fermentation broth of A. cinnamomea. It was found that corn oil from a group of vegetable oils exhibited the best effect on the biomass and triterpenoid content. After optimization, the initial addition of 1% (v/v) corn oil plus the inoculation of 10% (v/v) mycelia led to a maximum triterpenoid yield (532.3 mg L−1), which was increased as much as fourfold compared to the blank control. Differential transcriptome analysis demonstrated that corn oil significantly enriched several metabolic pathways including glycolysis/gluconeogenesis, propanoate metabolism and transmembrane hydrophobins. The enriched pathways interacted with deferentially expressed genes (DEGs) induced by corn oil treatment. Our research provides a potential strategy for the large production of triterpenoids by the improved fermentation of A. cinnamomea.

Efecto del pH y Sales Inorgánicas en la Degradación de Colorantes Industriales por Pleurotus Djamor

En la presente investigación se planteó el uso de la cepa Pd318 del hongo Pleurotus djamor como agente biorremediador, con el objetivo de evaluar su capacidad para degradar el colorante reactivo azul 19 (A19). Para ello se estudió la influencia que tienen cinco sales inorgánicas en el crecimiento y actividad lignolítica del hongo. Un cribado de sales inorgánicas en placa determinó que las sales CaCl2.2H2O y MnSO4.5H2O tienen mayor influencia en el desarrollo micelial y actividad lignolítica de la cepa. Ensayos de fermentación líquida (FEL) con diferentes combinaciones a distintas concentraciones de las sales de calcio y manganeso permitieron demostrar la capacidad de degradación del colorante azul 19 a los 7 días de fermentación líquida a temperatura ambiente y agitación constante. Los máximos porcentajes de degradación del colorante fueron obtenidos con las combinaciones A1B1 y A2B1 con 43,47% y 41,36%, respectivamente. Se observó que a un pH de 5 unidades se favorece la degradación del colorante. Los estudios en placa señalaron que la adición de sales de calcio y manganeso en 10 días de incubación favorecieron el desarrollo micelial y la actividad lignolítica de Pd318, mientras que en un sistema FEL de 7 días, únicamente la adición de manganeso influye favorablemente a la actividad lignolítica del hongo y en consecuencia a su capacidad de degradación de azul 19. Palabra clave: Colorante azul 19, degradación de colorantes, enzimas lignolíticas, Pleurotus djamor. Abstract In the present investigation, the use of the Pd318 strain of the Pleurotus djamor fungus as a bioremediation agent was proposed, with the aim of evaluating its ability to degrade reactive dye blue 19 (A19). For this, the influence of five inorganic salts on the growth and lignolytic activity of the fungus was studied. A plate screening of inorganic salts determined that the CaCl2.2H2O and MnSO4.5H2O salts have a greater influence on the mycelial development and lignolytic activity of the strain. Liquid fermentation tests (FEL) with different combinations at different concentrations of the calcium and manganese salts allowed to demonstrate the degradation capacity of the blue dye 19, after 7 days of liquid fermentation at room temperature and constant stirring, the maximum degradation percentages of the dye were obtained with the combinations A1B1 and A2B1 with 43.47% and 41.36% respectively. It was observed that at a pH of 5 units the degradation of the dye is favored. The plate studies indicated that the addition of calcium and manganese salts in 10 days of incubation, favored mycelial development and the lignolytic activity of Pd318, while in a 7 day FEL system, only the addition of manganese favorably influenced the lignolytic activity of the fungus and consequently its ability to break down blue 19. Keywords: Blue dye 19, dye degradation, lignolytic enzymes, Pleurotus djamor.

Increased Extracellular Saponin Production After the Addition of Rutin in Truffle Liquid Fermentation and Its Antioxidant Activities

Saponins possess a variety of pharmacological effects and exhibit great potential in the food industry as bioactive substances. In this study, extracellular saponin production via the liquid fermentation of Tuber melanosporum occurred with the addition of rutin. For this purpose, medium composition and culture conditions were optimized using single-factor experiments and an orthogonal experiment design. The optimal medium consisted of glucose (43.5 g/L), peptone (6 g/L), KH2PO4 (1.15 g/L), NaCl (0.2 g/L), vitamin B2 (0.082 g/L), vitamin B6 (0.1 g/L), vitamin C (0.02 g/L), and rutin (4.8 g/L). The culture conditions were as follows: 12.5% (v/v) inoculation, medium volume of 50 mL/250 mL flask, culture temperature of 24 °C, shaker speed of 190 rpm, initial pH of 5.7, and culture time of 96 h. Finally, a maximal extracellular saponin content of 0.413 g/L was obtained, which was 134.7% higher than that in the base medium. Rutin proved to be an excellent promoter, because the saponin production was increased by 50.2% compared to that in the optimized medium without rutin. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, hydroxyl radical scavenging activity, and ferric reducing antioxidant power of truffle saponins reached 94.13%, 79.26%, and 42.22 mM, respectively. This study provides a useful strategy for fungal bioactive saponin production by liquid fermentation with the addition of flavonoid compounds.

Integrated cycles for urban biomass as a strategy to promote a CO2-neutral society – a feasibility study

Progressive global warming is one of the biggest challenges civilization is facing today. The establishment of a carbon dioxide (CO2)-neutral society based on sustainable value creation cycles is required to stop this development. The Integrated Cycles for Urban Biomass (ICU) concept is a new concept towards a CO2-neutral society. The integration of closed biomass cycles into residential buildings enable efficient resource utilization and avoid transport of biowaste. In this scenario, biowaste is degraded on-site into biogas that is converted into heat and electricity. The liquid fermentation residues are upgraded by nitrification processes (e.g., by a soiling®-process, EP3684909A1) to refined fertilizer, which can be used subsequently in house-internal gardens to produce fresh food for residents.Whereas this scenario sounds promising, comprehensive evaluations of produced amounts of biogas and food, saved CO2 and costs as well as social-cultural aspects are lacking. To assess these points, a feasibility study was performed, which estimated the material and energy flows based on simulations of the biogas process and food production.The calculations show that a residential complex with 100 persons can generate 21 % of the annual power (electrical and heat) consumption from the accumulated biowaste. The nitrogen (N) in the liquid fermentation residues enables the production of up to 6.3 t of fresh mass of lettuce per year in a 70 m2 professional hydroponic production area. The amount of produced lettuce corresponds to the amount of calories required to feed four persons for one year. Additionally, due to the reduction of biowaste transport and the in-house food and fertilizer production, 6 468 kg CO2-equivalent (CO2-eq) per year are saved compared to a conventional building. While the ICU concept is technically feasible, its costs are still 1.5 times higher than the revenues. However, the model predictions show that the ICU concept becomes economically feasible in case food prices further increase and ICU is implemented at larger scale, e.g.; at the district level. Finally, this study demonstrates that the ICU implementation can be a worthwile contribution towards a sustainable CO2-neutral society and enable to decrease the demand for agricultural land.

Performance of Yeast Microbial Fuel Cell Integrated with Sugarcane Bagasse Fermentation for COD Reduction and Electricity Generation

The purpose of this analysis is to evaluate the efficiency of the Microbial Fuel Cell (MFC) system incorporated with the fermentation process, with the aim of reducing COD and generating electricity, using sugarcane bagasse extract as a substrate, in the presence and absence of sugarcane fibers. There is a possibility of turning bagasse extract into renewable bioenergy to promote the sustainability of the environment and energy. As a result, the integration of liquid fermentation (LF) with MFC has improved efficiency compared to semi-solid state fermentation (S-SSF). The maximum power generated was 14.88 mW/m2, with an average COD removal of 39.68% per cycle. The variation margin of the liquid fermentation pH readings remained slightly decrease, with a slight deflection of +0.14 occurring from 4.33. With the absence of bagasse fibers, biofilm can grow freely on the anode surface so that the transfer of electrons is fast and produces a relatively high current. Experimental data showed a positive potential after an effective integration of the LF and MFC systems in the handling of waste. The product is then simultaneously converted into electrical energy. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).