1
|
Carvalho JK, Krüger C, Silveira MAD, Piana PA, Rodrigues MLF, Rosado AF, da Silva de Lucca RA, Fagundes-Klen MR, da Silva EA, Buzanello CV, Teleken JG, Zanella RA. Lipolytic production from solid-state fermentation of the filamentous fungus Penicillium polonicum and its applicability as biocatalyst in the synthesis of ethyl oleate. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:28632-28643. [PMID: 38558334 DOI: 10.1007/s11356-024-33007-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 03/16/2024] [Indexed: 04/04/2024]
Abstract
Lipases represent versatile biocatalysts extensively employed in transesterification reactions for ester production. Ethyl oleate holds significance in biodiesel production, serving as a sustainable alternative to petroleum-derived diesel. In this study, our goal was to prospect lipase and assess its efficacy as a biocatalyst for ethyl oleate synthesis. For quantitative analysis, a base medium supplemented with Rhodamine B, olive oil, and Tween 80 was used. Solid-state fermentation utilized crambe seeds of varying particle sizes and humidity levels as substrates. In the synthesis of ethyl oleate, molar ratios of 1:3, 1:6, and 1:9, along with a total enzymatic activity of 60 U in n-heptane, were utilized at temperatures of 30 °C, 37 °C, and 44 °C. Reactions were conducted in a shaker at 200 rpm for 60 min. As a result, we first identified Penicillium polonicum and employed the method of solid-state fermentation using crambe seeds as a substrate to produce lipase. Our findings revealed heightened lipolytic activity (22.5 Ug-1) after 96 h of fermentation using crambe cake as the substrate. Optimal results were achieved with crambe seeds at a granulometry of 0.6 mm and a fermentation medium humidity of 60%. Additionally, electron microscopy suggested the immobilization of lipase in the substrate, enabling enzyme reuse for up to 4 cycles with 100% enzymatic activity. Subsequently, we conducted applicability tests of biocatalysts for ethyl oleate synthesis, optimizing parameters such as the acid/alcohol molar ratio, temperature, and reaction time. We attained 100% conversion within 30 min at 37 °C, and our results indicated that the molar ratio proportion did not significantly influence the outcome. These findings provide a methodological alternative for the utilization of biocatalysts in ethyl oleate synthesis.
Collapse
Affiliation(s)
- Jéssyca Ketterine Carvalho
- Department of Engineering and Exact, Federal University of Paraná, Palotina, PR, Brazil.
- Engineering and Exact Sciences Center, State University Western Paraná, Toledo, PR, Brazil.
| | - Cíntia Krüger
- Department of Engineering and Exact, Federal University of Paraná, Palotina, PR, Brazil
| | | | | | | | | | | | | | - Edson Antônio da Silva
- Engineering and Exact Sciences Center, State University Western Paraná, Toledo, PR, Brazil
| | | | - Joel Gustavo Teleken
- Department of Engineering and Exact, Federal University of Paraná, Palotina, PR, Brazil
| | | |
Collapse
|
2
|
de Moura Dickel JD, Carvalho JK, Silveira MAD, Menegotto Dos Santos P, Rodrigues MLF, Fagundes-Klen MR, Rosa CA, Johann S, Buzanello CV, da Silva de Lucca RA, de Oliveira Santos AR, da Rosa MF. Aspergillus sclerotiorum lipolytic activity and its application in bioremediation of high-fat dairy wastewater environments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:35517-35527. [PMID: 36529799 DOI: 10.1007/s11356-022-24669-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Oils and grease (O&G) have low affinity for water and represent a class of pollutants present in the dairy industry. Enzyme-mediated bioremediation using biocatalysts, such as lipases, has shown promising potential in biotechnology, as they are versatile catalysts with high enantioselectivity and regioselectivity and easy availability, being considered a clean technology (white biotechnology). Specially in the treatment of effluents from dairy industries, these enzymes are of particular importance as they specifically hydrolyze O&G. In this context, the objective of this work is to prospect filamentous fungi with the ability to synthesize lipases for application in a high-fat dairy wastewater environment. We identified and characterized the fungal species Aspergillus sclerotiorum as a good lipase producer. Specifically, we observed highest lipolytic activity (20.72 U g-1) after 96 h of fermentation using sunflower seed as substrate. The fungal solid fermented was used in the bioremediation in dairy effluent to reduce O&G. The experiment was done in kinetic from 24 to 168 h and reduced over 90% of the O&G present in the sample after 168 h. Collectively, our work demonstrated the efficiency and applicability of fungal fermented solids in bioremediation and how this process can contribute to a more sustainable wastewater pretreatment, reducing the generation of effluents produced by dairy industries.
Collapse
Affiliation(s)
| | - Jéssyca Ketterine Carvalho
- Engineering and Exact Sciences Center, State University Western Paraná, Toledo, PR, Brazil.
- Department of Engineering and Exact, Federal University of Paraná, Palotina, PR, Brazil.
| | - Maruhen Amir Datsch Silveira
- Centre de Recherche du CHU de Québec - Université Laval, Axe Oncologie, Quebec, QC, G1V 4G2, Canada
- Centre de Recherche Sur Le Cancer de L'Université Laval, Quebec, QC, G1R 3S3, Canada
| | | | | | | | - Carlos Augusto Rosa
- Microbiology Department, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Susana Johann
- Microbiology Department, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | | | | | | | | |
Collapse
|
3
|
Das S, Das S, Ghangrekar MM. Enzymatic cell disruption followed by application of imposed potential for enhanced lipid extraction from wet algal biomass employing photosynthetic microbial fuel cell. BIORESOURCE TECHNOLOGY 2022; 363:127924. [PMID: 36096325 DOI: 10.1016/j.biortech.2022.127924] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 09/03/2022] [Accepted: 09/05/2022] [Indexed: 06/15/2023]
Abstract
Solvent-free algal cell lysis using fungal enzyme for enhanced lipid recovery diminishes per unit production cost of algal biodiesel. In this investigation, a triple chamber photosynthetic microbial fuel cell (PMFC) was fabricated, where positive potential was imposed in the extraction chamber to draw the negatively charged lipid ions from the cathodic chamber. Under optimum imposed potential of + 3.0 V (vs standard hydrogen electrode) and with 3.5% (v/v) dosage of fungal enzyme in to the algal consortium of cathodic chamber, a maximum of 79.0% of lipid was recovered. Additionally, enzyme-assisted de-oiled algal biomass was applied in the anodic chamber to function as substrate and mediator for exo-electrogens, and the maximum power density of 10.0 W/m3 with 82.4% removal of chemical oxygen demand was achieved while treating synthetic wastewater. Therefore, this cost-effective exploration demonstrated successful bioelectricity production and concomitant wastewater treatment with solvent-free direct lipid recovery from wet algal biomass through PMFC.
Collapse
Affiliation(s)
- Swati Das
- PK Sinha Centre for Bioenergy & Renewables, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Sovik Das
- Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - M M Ghangrekar
- PK Sinha Centre for Bioenergy & Renewables, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India; Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
| |
Collapse
|
4
|
Babu S, Singh Rathore S, Singh R, Kumar S, Singh VK, Yadav SK, Yadav V, Raj R, Yadav D, Shekhawat K, Ali Wani O. Exploring agricultural waste biomass for energy, food and feed production and pollution mitigation: A review. BIORESOURCE TECHNOLOGY 2022; 360:127566. [PMID: 35788385 DOI: 10.1016/j.biortech.2022.127566] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
Globally agricultural production system generates a huge amount of solid waste. Improper agri-waste management causes environmental pollution which resulted in economic losses and human health-related problems. Hence, there is an urgent need to design and develop eco-friendly, cost-effective, and socially acceptable agri-waste management technologies. Agri-waste has high energy conversion efficiency as compared to fossil fuel-based energy generation materials. Agri-waste can potentially be exploited for the production of second-generation biofuels. However, composted agri-waste can be an alternative to energy-intensive chemical fertilizers in organic production systems. Furthermore, value-added agri-waste can be a potential feedstock for livestock and industrial products. But comprehensive information concerning agri-waste management is lacking in the literature. Therefore, the present study reviewed the latest advancements in efficient agri-waste management technologies. This latest review will help the researchers and policy planners to formulate environmentally robust residue management practices for achieving a green economy in the agricultural production sector.
Collapse
Affiliation(s)
- Subhash Babu
- Division of Agronomy, ICAR- Indian Agricultural Research Institute, New Delhi 110 012, India
| | - Sanjay Singh Rathore
- Division of Agronomy, ICAR- Indian Agricultural Research Institute, New Delhi 110 012, India.
| | - Raghavendra Singh
- ICAR- Indian Institute of Pulses Research, Kanpur, Uttar Pradesh 208 024, India
| | - Sanjeev Kumar
- ICAR- Indian Institute of Farming Systems Research, Modipuram, Uttar Pradesh 250110, India
| | - Vinod K Singh
- ICAR- Central Research Institute on Dryland Agriculture, Hyderabad, Telangana 500 059, India
| | - S K Yadav
- ICAR-Indian Institute of Sugarcane Research, Lucknow, Uttar Pradesh 226 002, India
| | - Vivek Yadav
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Horticulture, Northwest A & F University, Yangling 712100, China
| | - Rishi Raj
- Division of Agronomy, ICAR- Indian Agricultural Research Institute, New Delhi 110 012, India
| | - Devideen Yadav
- ICAR-Indian Institute of Soil & Water Conservation, Dehradun, Uttarakhand 248 195, India
| | - Kapila Shekhawat
- Division of Agronomy, ICAR- Indian Agricultural Research Institute, New Delhi 110 012, India
| | - Owais Ali Wani
- Division of Soil Science and Agricultural Chemistry, SKUAST- Kashmir, 193201, India
| |
Collapse
|
5
|
Evaluation of ultrasound waves for the production of chitinase and β-1,3 glucanase by Trichoderma harzianum through SSF. 3 Biotech 2022; 12:122. [PMID: 35547017 PMCID: PMC9038967 DOI: 10.1007/s13205-022-03179-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 03/31/2022] [Indexed: 12/23/2022] Open
Abstract
Cell wall degrading enzymes (chitinase and β-1,3-glucanase) were produced by solid-state fermentation (SSF) using the fungus Trichoderma harzianum and different agro-industrial products, mainly residues. The influence of temperature (25-35 °C), initial moisture content (50-90% w/w), nutrient solution (1-2% v/w), and yeast extract (1-2% w/w) on enzyme activity was evaluated. The application of ultrasound during fermentation for different times (0-6 h/day) was also studied. White rice was the substrate that showed the highest chitinase and β-1,3-glucanase activities, which were 31.31 U/g for chitinase and 23.83 U/g for β-1,3-glucanase after 10 days of fermentation. Application of ultrasound waves during fermentation positively affected (p < 0.05) the enzyme activities. The best results for chitinase (51.88 U/g) and β-1,3-glucanase (39.22 U/g) were obtained with a 50% (w/w) moisture content and 4 h/day ultrasound application for 10 days of fermentation. Increases of 3.6-fold (from 14.37 to 51.88 U/g) and 3.8-fold (from 10.22 to 39.22 U/g) in activities for chitinase and β-1,3-glucanase, respectively, compared to non-sonicated fermentation, were obtained. Ultrasound technique associated with the SSF process was a promising alternative to increase the production activity of cell wall degrading enzymes: chitinase and β-1,3-glucanase.
Collapse
|
6
|
Statistical optimization of lipase production from oil mill effluent by Acinetobacter sp. KSPE71. JOURNAL OF THE SERBIAN CHEMICAL SOCIETY 2022. [DOI: 10.2298/jsc220119038k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The present study investigated the valorization of oil-rich residues of
coconut oil mill effluent (COME) as a potential growth medium for the
microbial production of extracellular lipase. The bacterial species isolated
from oil mill effluent, Acinetobacter sp. KSPE71 was tested for its
efficiency to grow and produce lipase in undiluted COME and 0.2 % yeast
extract and 0.2 % NH4Cl sup-plemented COME. In this connection, the process
parameters such as pH, temperature, agitation speed, and inoculum size were
optimized to maximize the production using a central composite design in the
Response surface methodology. At the optimized state of pH 7.5, 35 ?C, 150
rpm with 0.6 % inoculum size, a maximum of 3.95 U mL-1 activity was
obtained, four-fold higher than the basal condition. At this stage, 73 % of
the lipid content was degraded. The present work results imply that the oil
mill effluent can be used as a cheaper production medium for lipase and the
new isolate Acinetobacter sp. KSPE71 as a potential lipase producer. The
degradation of oil waste along with the production of the valuable product
has multiple advantages of cost reduction of lipase and environmental
concern.
Collapse
|
7
|
Fernandes H, Moyano F, Castro C, Salgado J, Martínez F, Aznar M, Fernandes N, Ferreira P, Gonçalves M, Belo I, Oliva-Teles A, Peres H. Solid-state fermented brewer's spent grain enzymatic extract increases in vitro and in vivo feed digestibility in European seabass. Sci Rep 2021; 11:22946. [PMID: 34824341 PMCID: PMC8617204 DOI: 10.1038/s41598-021-02393-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 11/09/2021] [Indexed: 11/23/2022] Open
Abstract
Brewer's spent grain (BSG) is the largest by-product originated from the brewery industry with a high potential for producing carbohydrases by solid-state fermentation. This work aimed to test the efficacy of a carbohydrases-rich extract produced from solid-state fermentation of BSG, to enhance the digestibility of a plant-based diet for European seabass (Dicentrarchus labrax). First, BSG was fermented with A. ibericus to obtain an aqueous lyophilized extract (SSF-BSG extract) and incorporated in a plant-based diet at increasing levels (0-control; 0.1%, 0.2%, and 0.4%). Another diet incorporating a commercial carbohydrases-complex (0.04%; Natugrain; BASF) was formulated. Then, all diets were tested in in vitro and in vivo digestibility assays. In vitro assays, simulating stomach and intestine digestion in European seabass, assessed dietary phosphorus, phytate phosphorus, carbohydrates, and protein hydrolysis, as well as interactive effects between fish enzymes and dietary SSF-BSG extract. After, an in vivo assay was carried out with European seabass juveniles fed selected diets (0-control; 0.1%, and 0.4%). In vitro digestibility assays showed that pentoses release increased 45% with 0.4% SSF-BSG extract and 25% with Natugrain supplemented diets, while amino acids release was not affected. A negative interaction between endogenous fish enzymes and SSF-BSG extract was observed in both diets. The in vivo digestibility assay corroborated in vitro data. Accordingly, the dietary supplementation with 0.4% SSF-BSG increased the digestibility of dry matter, starch, cellulose, glucans, and energy and did not affect protein digestibility. The present work showed the high potential of BSG to produce an added-value functional supplement with high carbohydrases activity and its potential contribution to the circular economy by improving the nutritional value of low-cost and sustainable ingredients that can be included in aquafeeds.
Collapse
Affiliation(s)
- Helena Fernandes
- Department of Biology, Faculty of Sciences of University of Oporto (FCUP), Porto, Portugal.
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Matosinhos, Portugal.
| | - Francisco Moyano
- Department of Biology and Geology, University of Almería, Almería, Spain
| | - Carolina Castro
- Department of Biology, Faculty of Sciences of University of Oporto (FCUP), Porto, Portugal
| | - José Salgado
- Centre of Biological Engineering (CEB), University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal
| | - Francisca Martínez
- Department of Biology and Geology, University of Almería, Almería, Spain
| | - María Aznar
- Department of Biology and Geology, University of Almería, Almería, Spain
| | - Nelson Fernandes
- Department of Biology, Faculty of Sciences of University of Oporto (FCUP), Porto, Portugal
| | - Patrícia Ferreira
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Matosinhos, Portugal
| | - Margarida Gonçalves
- Department of Biology, Faculty of Sciences of University of Oporto (FCUP), Porto, Portugal
| | - Isabel Belo
- Centre of Biological Engineering (CEB), University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal
| | - Aires Oliva-Teles
- Department of Biology, Faculty of Sciences of University of Oporto (FCUP), Porto, Portugal
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Matosinhos, Portugal
| | - Helena Peres
- Department of Biology, Faculty of Sciences of University of Oporto (FCUP), Porto, Portugal
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Matosinhos, Portugal
| |
Collapse
|
8
|
Cano y Postigo LO, Jacobo-Velázquez DA, Guajardo-Flores D, Garcia Amezquita LE, García-Cayuela T. Solid-state fermentation for enhancing the nutraceutical content of agrifood by-products: Recent advances and its industrial feasibility. FOOD BIOSCI 2021. [DOI: 10.1016/j.fbio.2021.100926] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
9
|
Potential Role of Sequential Solid-State and Submerged-Liquid Fermentations in a Circular Bioeconomy. FERMENTATION 2021. [DOI: 10.3390/fermentation7020076] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
An efficient processing of organic solid residues will be pivotal in the development of the circular bioeconomy. Due to their composition, such residues comprise a great biochemical conversion potential through fermentations. Generally, the carbohydrates and proteins present in the organic wastes cannot be directly metabolized by microorganisms. Thus, before fermentation, enzymes are used in a hydrolysis step to release digestible sugars and nitrogen. Although enzymes can be efficiently produced from organic solid residues in solid-state fermentations (SsF), challenges in the development and scale-up of SsF technologies, especially bioreactors, have hindered a wider application of such systems. Therefore, most of the commercial enzymes are produced in submerged-liquid fermentations (SmF) from expensive simple sugars. Instead of independently evaluating SsF and SmF, the review covers the option of combining them in a sequential process in which, enzymes are firstly produced in SsF and then used for hydrolysis, yielding a suitable medium for SmF. The article reviews experimental work that has demonstrated the feasibility of the process and underlines the benefits that such combination has. Finally, a discussion is included which highlights that, unlike typically perceived, SsF should not be considered a counterpart of SmF but, in contrast, the main advantages of each type of fermentation are accentuated in a synergistic sequential SsF-SmF.
Collapse
|
10
|
Šelo G, Planinić M, Tišma M, Tomas S, Koceva Komlenić D, Bucić-Kojić A. A Comprehensive Review on Valorization of Agro-Food Industrial Residues by Solid-State Fermentation. Foods 2021; 10:foods10050927. [PMID: 33922545 PMCID: PMC8146281 DOI: 10.3390/foods10050927] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/19/2021] [Accepted: 04/21/2021] [Indexed: 12/18/2022] Open
Abstract
Agro-food industrial residues (AFIRs) are generated in large quantities all over the world. The vast majority of these wastes are lignocellulosic wastes that are a source of value-added products. Technologies such as solid-state fermentation (SSF) for bioconversion of lignocellulosic waste, based on the production of a wide range of bioproducts, offer both economic and environmental benefits. The versatility of application and interest in applying the principles of the circular bioeconomy make SSF one of the valorization strategies for AFIRs that can have a significant impact on the environment of the wider community. Important criteria for SSF are the selection of the appropriate and compatible substrate and microorganism, as well as the selection of the optimal process parameters for the growth of the microorganism and the production of the desired metabolites. This review provides an overview of the management of AFIRs by SSF: the current application, classification, and chemical composition of AFIRs; the catalytic function and potential application of enzymes produced by various microorganisms during SSF cultivation on AFIRs; the production of phenolic compounds by SSF; and a brief insight into the role of SSF treatment of AFIRs for feed improvement and biofuel production.
Collapse
|
11
|
Screening of Organic Substrates for Solid-State Fermentation, Viability and Bioefficacy of Trichoderma harzianum AS12-2, a Biocontrol Strain Against Rice Sheath Blight Disease. AGRONOMY-BASEL 2020. [DOI: 10.3390/agronomy10091258] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The present study was undertaken to find the most suitable organic substrates for the biomass production, viability and efficacy of the biocontrol strain Trichoderma harzianum AS12-2 in the solid-state fermentation system. In total, 13 inexpensive, locally available substrates (agricultural wastes or by-products) were inoculated with the antagonist, and following one month of incubation at room temperature, all colonized substrates were air dried and ground to powder. The shelf life and viability of the Trichoderma strain were assessed as colony-forming units per gram (CFUs g−1) of each substrate on a monthly basis for up to one year at room temperature (25 ± 2 °C) and in the refrigerator (4 °C). In order to find out the effect of the substrate on the bioefficacy of T. harzianum AS12-2, the biocontrol potential of the formulations was evaluated against rice sheath blight disease caused by Rhizoctonia solani. The results showed that the fungus colonized more or less all substrates after one month, although the degree of colonization and conidiation was different among the substrates, being especially high in broom sorghum grain, rice husk, rice straw, rice bran and sugar beet pulp. Analysis of variance (ANOVA) of the population in the substrates in “Month 0” showed that the effect of treatment was significant, and the means were significantly different. The maximum population was recorded for broom sorghum grain and rice straw (6.4 × 1010 and 5.3 × 1010 CFUs g−1, respectively). The population declined in all substrates after one year of incubation at room temperature. This decline was relatively smaller in broom sorghum grain, rice straw and rice husk. On the other hand, the population in the same substrate incubated in the refrigerator was decreased in a mild slope, and the final population was high. In addition, the results of greenhouse assay showed that all bioformulations were effective in controlling the disease, and there were no significant differences among the substrates. According to the results of this study, broom sorghum grain, rice husk, rice straw, sugar beet pulp and cow dung could be recommended as suitable fermentation media for the industrial-scale production of T. harzianum strains.
Collapse
|