Technical sessions-Abstracts-Oral Session 2-OS-21-OS-26

36th Ann. Meeting of MSI & Nat. Seminar on Fungal Biodiversity & Bioprospecting….. Goa, India Oct., 29-30, 2009

ORAL SESSION 2

OS – 21

Ornamentation in ectomycorrhizal fungal spores – is it an adaptation for their dispersal within host range?

Kumaresan V., *Ravindran C., **Senthilarasu G. and Ganesan T.
Department of Plant Science, Tagore Arts Colleges, Puducherry 605 008.
*Marine Biotechnology, National Institute of Oceanography, Dona Paula, Goa 403 004.
**Mycology and Plant Pathology Group, Agharkar Research Institute, Pune 411 004.

Fungi belonging to Ascomycota, Basdiomycota and Zygomycota are known to form ectomycorrhizal associations with many woody plant species. A survey of literature with regard to these fungi revealed that more than 60% of the genera that are known to form ectomycorrhizal associations showed spore ornamentations. It is known that the spores are dispersed by agents such as wind and components of animal kingdom, but, in the case of dense forests, blocking of the wind by canopy makes the forest floor a calm place. Thus, other than the above two factors rain water could form an important medium for the dispersal of spores. We propose that spore ornamentation is a important adaptation for their dispersal within host range since the fruiting structures are formed (and they mature) during rainy period and therefore the spores are dispersed/washed along with rain water, in the sloppy terrain, that can carry them to long distances if there is no resistance provided by the spores ultimately taking them out of the host range.

OS – 22

Stimulation of taxol production by Pestalotiopsis breviseta (Sacc.) Steyaert using the biotic and abiotic elicitors

G. Kathiravan and J. Muthumary*
Department of Biotechnology, Vels University, Pallavaram, Chennai 600 117.
* CAS in Botany, University of Madras, Guindy Campus, Chennai 600 025.

Coelomycetes are known mainly from tropical and temperate regions, less so from the Antartic and Artic are capable of growing, reproducing and surviving in a wide variety of ecological situations. Coelomycetous fungi Pesalotiopsis breviseta (Sacc.) Steyaert was screened for the production of taxol an anticancer drug. Taxol production was conformed by following methods Ultra Violet (UV) spectroscopic analysis, Infrared analysis (IR), High performance liquid chromatography analysis (HPLC) and Liquid chromatography mass spectrum (LC - MASS). The taxol produced by the fungi was compared with authentic taxol and biotic (Fungal elicitor) and abiotic elicitors (Copper Sulphate).

OS – 23

Screening of diverse fungi for Laccases of varying properties

Pranali Bodke*, G. Senthilarasu* and S. Raghukumar
Mykotech Pvt. Ltd., Mapusa Industrial Estate, Mapusa Goa 403507.
*Agharkar Research Institute, G.G. Agarkar Road, Pune 411 004.

Laccases are blue multi copper oxidase enzymes, containing copper atoms in the catalytic centre. They have received a lot of attention from researchers due to their broad substrate specificity and ability to oxidize various aromatic and non aromatic compounds, making them useful as biocatalysts for diverse biotechnological and industrial applications. Laccases are found in plants, insects and bacteria, but their major source is fungi, especially the Basidiomycetes. Various industrial and biocatalysis applications require laccases with specific properties. Our objective was to screen diverse fungi to obtain laccases showing activity at different pH and temperature.A total of 292 fungi belonging to Ascomycetes, Basidiomycetes and Deuteromycetes were qualitatively assayed using Guaiacol Oxidation Plate assay. Out of these, 120 were positive for Laccase. Fifty of these were selected for quantitative analysis. These were grown in liquid stationary culture conditions, harvested and spectrophotometrically analyzed using ABTS as the substrate at pH 3, 4.5 and 6. Ganoderma sp., Lentinus sp., Geotrichum sp. showed maximum activity at all three pH. Most of the fungi showed maximum laccase activity at 4.5 pH. Some fungi had pH optima at 3 whereas others showed high activity at pH 6. Further assays were carried out at 3 different temperatures in optimum pH condition to determine temperature optima of 25 cultures. Geotrichum sp., Lentinus sp., Agaricus sp. and an unidentified basidiomycete showed excellent activity at 300C, 450C and 600C. Some fungi showed good activity specifically at a particular temperature namely 300C, 450C or 600C.
OS – 24

Purification and characterization of pharmaceutically active compounds from an edible mushroom Calocybe indica P. & C.

S. Rajasekar*, P. Selvakumar, K. Periasamy and N. Raaman
Fungal Biotechnology, Natural Products and Tissue Culture Laboratory
Centre for Advanced Studies in Botany, University of Madras
Guindy Campus, Chennai 600 025.
*E-mail: rajasekar.ram@gmail.com

Fungi are well known for the production of pharmaceutical components. However, the distribution of bioactive compounds in the class of basidiomycetes (mushrooms) is less documented. In the present study, the edible mushroom C.indica was extracted with different organic solvents and screened for the antimicrobial activity against human pathogens. The bioactive compound was isolated and purified by different chromatographic techniques. The antimicrobial activity and minimal inhibitory concentration (MIC) of the purified bioactive compound 5,6,11,12,13,15,16, 17-octahydro-6, 11-dihydroxy-4,4,10,13-tetramethyl-17-((E)-5, 6-dimethyl hept-3-en-2-yl)-4H-cyclopenta [a] phenanthren-3(9H,10H,14H)-one was tested, it showed good antimicrobial activity. Moreover, partially purified polysaccharide (CiP) from C. indica was tested for in vitro antioxidant activity and it showed good scavenging activity against lipid peroxidation, hydroxyl radical peroxidation, DPPH scavenging activity and superoxide scavenging activity. In addition, hepatoprotective activity of CiP was studied in acetaminophen (AAP) induced liver damaged rats. The depletion of protein, uric acid, SOD, CAT and GSH levels were prevented in the C. indica polysacciaride pretreated rats. The elevated level of ALP, SGOT, SGPT, iron and LPO were recorded in AAP induced liver damaged rats, but in CiP pretreated group the elevation of these marker enzymes was protected. Histopathological reports also supported the prevention of hepatocyte necrosis. Besides, the antitumor activity of the CiP was tested in mice developed with tumor induced by Ehirlich’s ascities carcinoma (EAC). Animals treated with CiP showed reduction in tumor weight and tumor volume. Interestingly, polysaccharide did not show cytotoxicity on EAC cells, it was concluded that the antitumor activity may be due to the immunomodulatory activity of polysaccharide. Further, the polysaccharide was purified on DEAE-cellulose, sepharose-6B column chromatogram and identified as (1→ 4)-α- and (1→ 6) -β-glucan.



OS – 25

Assessment of patulin and citrinin contamination in different grades of walnut (Juglans regia L.) kernels

Rohini Sharma* and Geeta Sumbali
Department of Botany, University of Jammu, Jammu 180 006.
*E-mail: sharmarohini25@yahoo.co.in

Walnut (Juglans regia L.) commonly called as akhrot is an important dry fruit that is grown extensively in Jammu and Kashmir State, which is the main walnut-producing zone of our country. Walnuts are rounded, single-seeded stone fruits which provide health benefits because of the presence of high amounts of omega-3 fatty acids, particularly alpha linoleic acid.
In view of the importance of walnut in day to-day life, a study was conducted to assess the molds and mycotoxins associated with this important nut. Samples of different grades of walnut kernel-in-shelled, shelled and broken pieces were collected from different markets of Jammu and Kashmir and analysed for patulin and citrinin production.Out of the total samples screened for qualitative estimation by thin layer chromatography (TLC), 72% in-shelled, 40% halves and 30% broken kernels were found to be positive for patulin contamination. Similarly, 67% in-shelled, 80% halves and 76% broken kernels were recorded positive for citrinin production.
Quantitative estimation of these samples by HPLC gave varied amounts of these fungal contaminants. High levels of mycotoxin contamination in walnuts is of great concern as it may produce adverse effects rather than benefit to the health of consumers.

OS – 26

Variation in production of glucanase by Ganoderma lucidum (Curtis) p. Karst

C. K. Tiwari*, Jagrati Parihar and R. K. Verma
Forest Pathology division, Tropical Forest Research Institute, Jabalpur 482 021 (M. P.)
*E-mail: ck_scientist@yahoo.com

Cellulose is the most abundant and renewable source of energy on earth. Its conversion to soluble sugar is preferred by enzymatic hydrolysis and involves cellulases that provide a key opportunity for achieving the tremendous benefits of biomass utilization. Cellulases interactively promote the cellulose degradation to cope with problem of food and energy shortage expected in near future with explosive increase in human population. A number of fungi capable of utilizing
cellulose as a carbon source have been identified. Cellulose by the synergistic action of endo and exo- glucanase is converted to oligosaccharide and cellobiose, while beta glucosidase completes the hydrolysis by converting cellobiose and oligosugar into glucose.
Eighty strain of Ganoderma lucidum (Curtis) P. Karst were collected from different tree species, from Madhya Pradesh, Chattisgarh and Maharashtra, out of these four isolates found on Dalbergia sissoo Roxb. (TF844), Eucalyptus tereticornis Sm. (TF 854), Azadirachta indica A. Juss (TF912) and Acacia catechu (L.f.) Willd. (TF904), were screened for quantitative estimation of glucanase production. G. lucidum on Dalbergia sisso is the best glucanase producer (79.67µg mg-1 ml-1) as compared to other isolates collected from Eucalyptus tereticornis, Acacia catechu and Azadirachta indica. It is concluded that production of glucanase vary among the isolates of G. lucidum collected from different tree species.