DefinePK hosts the largest index of Pakistani journals, research articles, news headlines, and videos. It also offers chapter-level book search.
Title: Screening of selected plant products as alternatives to agar in mycological studies
Authors: Chinyerum Gloria Ikechi-Nwogu, Eunice Oluchi Nwachukwu
Journal: Mycopath
| Category | From | To |
|---|---|---|
| Y | 2024-10-01 | 2025-12-31 |
Publisher: University of the Punjab, Lahore
Country: Pakistan
Year: 2023
Volume: 20
Issue: 1
Language: English
  This study was carried out to examine the use of selected plant products as alternative to agar for mycological studies because agar is expensive and not readily available. Extracts from Aloe vera leaves (aloe), Terminalia ivorensis bark (black afara), Hevea brasiliensis (rubber tree), Abelmoschus esculentus pod (lady finger), seeds of Detarium macrocarpum (sweet detar), Brachystegia eurycoma (naga), Mucuna sloanei ( hamburger bean ) and Telfairia occidentalis (fluted pumpkin), grains of Triticum sp. (wheat), Zea mays (maize) and Oryza sativa (rice) , tubers of Colocasia esculenta (cocoyam), Manihot esculenta (cassava), Dioscorea bulbifera (aerial yam), Ipomoea batatas (sweet potatoes), Dioscorea rotundata  (white yam) and Dioscorea dumetorum (three-leaved yam) were screened as alternative to agar for cost reduction. These plant extracts combined with potato and dextrose in varying concentrations (5, 10, 15, 20, 25, 30, 35, 40, 45 and 50 g 100 mL -1 ), were tested for their gelling potentials. The different concentrations of all the plant products were tested at different periods (1 s to 1 h), under different temperature (20–90 o C). The media did not solidify except potato dextrose cassava starch (PDCS) which solidified at 50 g 100 mL in 30 min and at 29 o C. Seven frequently occurring fungi ( Aspergillus niger, Aspergillus flavus, Botrydioplodia theobromae, Fusarium poae, Penicillium chrysogenum, Rhizopus oryzae and Trichoderma harzianum ) were cultured on PDCS and PDA (potato dextrose agar) for comparison to evaluate their abilities in supporting fungal growth.  The radial growth and mycelial biomass of the test fungi were recorded and subjected to ANOVA. Mycelial biomass values (g) for each test organism for PDCS and PDA were: 3.77 ± 0.64 and 3.94 ± 0.53 for A. flavus ; 4.09 ± 1.51 and 2.14 ± 0.41 for A. niger; 8.08 ± 0.19 and 4.97 ± 1.74 for B. theobromae ; 1.04 ± 0.32 and 1.97 ± 0.25 for F. poae ; 6.42 ± 0.14 and 5.40 ± 0.16 for P. chrysogenum ; 7.10 ± 0.86 and 5.88 ± 0.14 for R. oryzae and 5.08 ± 1.02 and 4.30 ± 2.64 for T. harzianum . The mycelia biomass of A. flavus and T. harzianum on PDCS, are not significantly different at P ≤0.05 from those on PDA. While those of A. niger, B. theobromae, F. poae, P. chrysogenum and R. oryzae on PDCS were significantly higher than those on PDA. All the tested fungi exhibited normal growth and sporulation on PDCS when compared with PDA (control), but with better growth on PDCS at P ≤0.05.  
To examine the use of selected plant products as alternatives to agar for mycological studies due to agar's high cost and limited availability, and to determine their gelling properties and effectiveness in supporting fungal growth.
The study involved screening various plant products (aloe vera leaves, Terminalia ivorensis stem bark, Hevea brasiliensis latex, Abelmoschus esculentus pod, seeds of Detarium macrocarpum, Brachystegia eurycoma, Mucuna sloanei, Telfairia occidentalis, and grains of Triticum sp., Zea mays, Oryza sativa, tubers of Colocasia esculenta, Manihot esculenta, Dioscorea bulbifera, Ipomoea batatas, Dioscorea rotundata, and Dioscorea dumetorum) as potential solidifying agents. These plant extracts were combined with potato and dextrose in varying concentrations (5-50 g per 100 mL) and tested for gelling potential under different time (1 s to 1 h) and temperature (20-90 °C) conditions. Seven frequently occurring fungi were cultured on the most promising alternative medium, potato dextrose cassava starch (PDCS), and compared with potato dextrose agar (PDA) for their ability to support fungal growth. Radial growth and mycelial biomass were recorded and analyzed using ANOVA.
graph TD
A[Select Plant Products] --> B[Extract/Prepare Solidifying Agents];
B --> C[Combine with Potato Dextrose Broth];
C --> D[Test Gelling PotentialConcentration, Time, Temp];
D --> E[Identify Promising AgentPDCS];
E --> F[Isolate Fungi];
F --> G[Culture Fungi on PDCS and PDA];
G --> H[Evaluate Fungal GrowthRadial Growth, Biomass, Sporulation];
H --> I[Analyze Data ANOVA];
I --> J[Draw Conclusions];
The study highlights the potential of cassava starch as a cost-effective and biodegradable alternative to agar for mycological studies. While some plant products failed to solidify or support fungal growth due to factors like antimicrobial properties or antinutritional factors, cassava starch demonstrated promising gelling and growth-supporting capabilities. The nutritional composition of cassava starch, including higher carbohydrate and protein content compared to agar, likely contributes to its effectiveness. The study also notes that PDCS maintained its viscosity for up to four weeks, making it suitable for routine mycological studies.
Only potato dextrose cassava starch (PDCS) at a concentration of 50 g/100 mL solidified effectively within 30 minutes at 29 °C. Seven test fungi exhibited normal growth and sporulation on PDCS, with better growth observed on PDCS compared to PDA (control) at P<0.05. Mycelial biomass of Aspergillus flavus and Trichoderma harzianum on PDCS was not significantly different from PDA, while other tested fungi showed significantly higher mycelial biomass on PDCS than on PDA. Cassava starch was found to be over 80 times cheaper than agar.
Cassava starch is a viable and inexpensive alternative to agar for preparing culture media for fungal growth. Its availability, ease of extraction, and ability to support fungal growth and sporulation make it a recommended substitute, particularly in developing countries like Nigeria where agar is imported.
1. Cassava starch cost: The study states cassava starch is over 80 times cheaper than agar.
2. Solidification of PDCS: Potato dextrose cassava starch (PDCS) solidified at 50 g/100 mL in 30 minutes at 29 °C.
3. Mycelial biomass comparison: Mycelial biomass of Aspergillus niger, Botrydioplodia theobromae, Fusarium poae, Penicillium chrysogenum, and Rhizopus oryzae on PDCS was significantly higher than on PDA.
Loading PDF...
Loading Statistics...