Technical Sessions-Abstracts-Oral session 4-OS-41-OS-48

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

ORAL SESSION 4

OS – 41

Biosynthesis of Silver Nanoparticles Using Fungi

Anima Nanda*, Bijaya Kumar Nayak**
Department of Biomedical Engineering, Sathyabama University, Rajiv Gandhi Salai, Chennai 600 119.
**Department of Plant Biology & Biotechnology, K. M. Centre for P.G. Studies (Autonomous),
Airport Road, Pondicherry 605 008.
*E-mail: biju_nandu@yahoo.com

Nanotechnology is the science of creating or modifying materials at the atomic and molecular level to develop new or enhanced materials and products. Silver bio-nanoparticles (Ag-NPs) are known to possess bactericidal effects. The present study aims at development of extra-cellular biosynthesis of silver bio-nanoparticles using Aspergillus niger, Aspergillus flavus and Trichoderma harzianum and evaluated their antimicrobial activity against pathogenic bacteria. Ag-NPs will be synthesized by reducing Ag+ ions with the culture supernatants of Aspergillus niger, Aspergillus flavus and Trichoderma harzianum. The bio-reduction of the Ag+ ions in the solution assayed spectrophotometrically and allowed further confirmed by atomic force microscopy (AFM). The nano-bioparticles so obtained was evaluated for their antimicrobial activities against the target pathogen using standard methods of optimization. The most sensitive antimicrobial activity has been observed and zone of inhibition was recorded against various pathogens.

OS – 42

Production, Purification, Characterization and Biodiesel production by Extracellular lipases from oil seed-associated-fungi using Solid State Fermentation

V. Balaji* and P. Ebenezer
Centre for Advanced Studies in Botany, University of Madras, Chennai 600 025.
*E-mail: kvsbalaj@gmail.com

Oil-yielding seeds were collected from different places in the state of Tamil Nadu, India. In total, 1279 fungal isolates were recovered from the oil seeds. The fungal isolates were screened for their lipolytic activity. Out of 1279, only 40 isolates turned out to be promising interms of the enzyme yield onTween-20 Agar. These taxa were analysed stastically for the Colonization Frequency percentage (CF%), Diversity Indices, Shannon-Index H', Dominance Index, Simpson’s Index D, Species Richness (Chao) in oil seeds. The oil-yielding seeds exhibited rich fungal diversity. Quantification analysis of lipase production by these isolates revealed that Aspergillus niger (94 U/mL), Chalaropsis thielavioides (96 U/mL), Lasiodiplodia theobromae (108 U/mL), Phoma glomerata (95 U/mL) and Colletotrichum gloeosporioides (98 U/mL) produced appreciable quantities of the enzyme. Out of the above five good lipase producing isolates, Lasiodiplodia theobromae produced the maximum lipase units and therefore, the same isolate was chosen for further studies. The taxonomic identity of Lasiodiplodia theobromae was estabilished both morphometry and molecular methods. Lipase-producing ability was evaluated by Solid State Fermentation (SSF). Coconut oil cake appeared to be the best fermentation substrate for lipase production by L. theobromae VBE1 and hence the same was used through out the study. Optimization of lipase production by Response Surface Methodology (RSM) involved four factors― Central Composite Design involving 30 experiments was employed. On validating the predicted levels from the RSM, the enzyme production rose steeply. The enzyme so optimized was purified and characterized subsequently. Two distinct bands denoting two isoforms Lip A and Lip B appeared on the gels were separated by Q-Sepharose Column and Gel Filtration Chromatographic columns. The molecular mass of Lip A as determined on SDS-PAGE was 68 kDa and for Lip B it was 32 kDa. Purified lipase was used to generate Fatty Acid Methyl Esters (FAME/Biodiesel) from coconut and pogamia oils by both Lip A and NaOH catalytic action and were analysed by GC, GC-MS, IR, 1H NMR, 13C NMR. The other details will be presented in the paper.

OS – 43

Cardiovascular- protective and antimicrobial activity of a lichen species Usnea complanata

N. D. Mahadik, M. V. Morey and B. C. Behera
Agharkar Research Institute, G.G. Agarkar Road, Pune 411 004 (M.S.)

The purpose of the present study was to investigate the cardiovascular protective and antimicrobial properties of a lichen Usnea complanata. The biological active compounds the thallus of Usnea complanata was extracted in various solvents viz. methanol, ethanol, acetone, hexane, ethyl acetate and dimethyl sulfoxide (DMSO). As far as cardiovascular protective properties of U. complanata is concerned ethyl acetate extract showed maximum HMG-CoA reductase (HMGR) inhibitory activity up to 52.87% at 200μg/ml. Ethanol extract showed 46.37% inhibitory activity against angiotensin converting enzyme (ACE). Maximum fibrinolytic activity was obtained in methanol extract followed by hexane extract. Fibrinolytic activity showed by methanol extract at 100μg/ml was more than that of the activity obtained by standard plasmin at 10μg/ml. As far as antimicrobial activity of U. complanata is concerned, all extracts except the DMSO and hexane showed inhibitory activity against bacteria and fungi. Ethyl acetate extract was found to be the most efficient, since MIC90 was found in the range of (4.61μg/ml – 21.55μg/ml) which was low as compared to MIC90 of all other extract, against all bacterial cultures tested. Regarding the antifungal activity of extract of U. complanata, acetone and ethyl acetate extract inhibited all the tested fungi. The MIC ranged from 6.25 to 100μg/ml for ethyl acetate extract and was 12.5 to 100μg/ml for acetone extract.


OS – 44

Lichen metabolites developed in vitro and their antioxidative properties

Neeraj Verma* and B.C. Behera
Mycology & Plant Pathology Group,
Agharkar Research Institute, G.G. Agarkar Road, Pune 411 004 (M.S.).
*Email: neerajverma2310@gmail.com

Epidemiological studies have shown that free radicals have the potential to damage biological compounds and structures such as proteins, membrane lipids, DNA and carbohydrates and that such damages caused by these radicals are said to be involved in the etiology and pathogenesis of different diseases such as carcinogenesis, coronary heart disease, and many other health problems associated at advancing age. Antioxidants are considered as possible protective agents against oxidative damage. Therefore, there is a growing interest in the substances exhibiting antioxidant properties that are supplied to humans as food components or as specific pharmaceutical products. Recently, natural antioxidants have become one of the major areas of scientific research. The plant kingdom offers a wide range of natural antioxidants. However, little is known about the practical usefulness of most of them. Lichens are stable and self supporting symbioses between fungi (the mycobiont) and photoautotrophic algal partners (the photobiont). Lichen-forming fungi are potential sources of interesting novel metabolites known as “lichen substances”. These lichen metabolites are known to exert multiple pharmacological activities and properties such as antibiotic, antimycobacterial, antiviral, antiinflammatory, antioxidative, analgesic, antipyretic, antiproliferative and cytotoxic effects.
With this background information cell aggregates composed of mycobiont and photobiont derived from three lichen species, Arthothelium awasthii, Heterodermia podocarpa and Parmotrema tinctorum, were grown in Lilly-Barnett (LB) and Modified Bold’s Basal (MBB) media for one year under laboratory conditions. The results on growth rate, production of lichen substances barbatic acid, zeorin and lecanoric acid, and the antioxidant potential of extracts prepared with different solvents and of the partially purified substances are presented. The growth rate of the cell aggregates of the three species was found to be more or less similar in the LB and MBB media. The production of lichen substances by the three species was found to vary in both the media. The dried, soluble extract yield found from the different solvents was in the order of DMSO > methanol > acetone > ethyl acetate > chloroform > n-hexane. The antioxidant activities showed by barbatic acid, zeorin and lecanoric acid was highest at a concentration of 50µg/ml.

OS – 45

Bioactive polysaccharide isolated from pink oyster mushroom Pleurotus djamor var. roseus

N. Raaman*, R. Jegadeesh, L. Hariprasath, G. Rajasekhar Reddy, S. Archana and K. Balasubramanian
Fungal Biotechnology, Natural Products and Tissue Culture Laboratory, Centre for Herbal Sciences,
Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai 600 025.
*E-mail: raaman55@gmail.com

Higher fungi are abundant sources of a wide range of useful natural products and new products with interesting biological activities. Many species in polysaccharide, a big class of natural macromolecules, have been found to carry significant biological activities. It has been reported that polysaccharides derived from medicinal mushroom have activities of anti-infection, anti-agening, anti-radiation, immunomodulation and hepatoprocetive etc. All these activities are due to its contribution to enhance immune function of the human body. The presence study is focused to find out the medicinal properties of Pleurotus djamor var. roseus. The mushroom cultivated in Centre for Advanced Studies in Botany mushroom shed, freshly harvested mushroom were dried and make it a coarse powder. Water soluble glucans was isolated from basidiocarp of P.djamor var. roseus, by subsequent hot water extraction and ethanol precipitation. Obtained crude polysaccharide was treated with sevage reagent for removal of protein contaminations. The resulted partially purified polysaccharide was passing through DEAE cellulose Ion exchange chromatography and sapharose 6B gel permeation chromatography. The resulted FrA, fraction was characterized by analytical method. The spectroscopic analysis confirmed that purified fraction was a polysaccharide. Isolated polysaccharide was tested for in vitro antioxidant activity and its showed the IC50 of DPPH and hydroxyl radical scavenging activity 165 μg and 190 μg concentrations.

OS – 46

Optimization of medium and process parameters for the production of lipase from a newly isolated Aspergillus sp (RBD-01)

Satnam Singh Aulakh, N.Tejo Prakash*, Ranjana Prakash**
School of Chemistry and Biochemistry, Thapar University, Patiala.
*Department of Biotechnology and Environmental Sciences, Thapar University, Patiala.
**E-mail: rprakash@thapar.edu

Extracellular lipase production by Aspergillus sp. was monitored by modulating pH of the growth medium, ambient temperature for growth, source of nitrogen and percentage of carbon (virgin cottonseed oil). This strain was observed to be viable and produce lipase even up to 50% oil as a main carbon source. Maximum lipase activity of 21.8 U/ml was obtained with 50% (v/v) oil as main carbon source and peptone (0.5% w/v) as nitrogen source. The optimum pH and temperature for enzymatic activity was observed to be 7.5 and 35°C respectively. The observations are of significance due to limited reports on use 50% of oil as main carbon source and obtaining significant lipase activity of 21.8U/ml.

OS – 47

Evaluation the Probable mechanism of action of fungal bioactive compounds through bioinformatics

Shyamji Shukla* and A.K. Pandey
Mycology Research laboratory, Department of Biological Sciences, RDVV, Jabalpur (M.P.)
*Email: ji_shyam1@yahoo.com

Computer-based assessment of potential toxicity has become increasingly popular in recent years. Determination of toxicity of the drugs used in human welfare is still a big challenge for all the scientist working on discovery and development of drugs, due to its failure in certain instances. Interest in the use of Computer-based programs for toxicity prediction based on chemical structure is increasing due to the high cost and societal objections to animal testing, and the large numbers of candidate chemicals for screening. This challenge is global in its objective, but limited in its solution, to within local domains of chemicals acting according to similar mechanisms of action in the biological system. To predict the mechanisms of action of new fungal bioactive compoundsmycotoxins, some degree of generalization based on chemical structure must be possible through PASS (Prediction of activity structure for substances). The concept of the biological activity spectrum was introduced to describe the properties of biologically active substances. The PASS is a software product, use to predict pharmacological effects and biochemical mechanisms on the basis of the structural, formula of a compound. It may be efficiently used to find new targets for some ligands and, conversely, to reveal new ligands for some biological targets. Therefore, realizing the need and importance of this software, the present work was carried out with objective to predict the mechanism of action of fungal bioactive compounds obtained from several plant pathogenic fungi with the help of this tool.

OS – 48

Selection of potential isolates of Laccaria fraterna and Pisolithus albus on growth improvement of Acacia auriculiformis and A. mangium

V. Mohan* and P. Manokaran
Forest Pathology Lab., Forest Protection Division, Institute of Forest Genetics and Tree Breeding
Coimbatore 641 002.

In India, though a number of mycorrhizas have been collected, identified and described by various researchers but most of the work appears on endomycorrhizal fungi with agricultural, horticultural and few forestry crops. Limited reports are available on ectomycorrhizal association with economically important forestry species like Acacias, Eucalypts and other plantation crops. The host dependency on mycorrhizal fungi is common phenomenon in forest ecosystem but its efficiency is influenced by numerous biotic and abiotic factors particularly much depends upon the host plants and fungal isolates/strain. Therefore, there is a need for development of reliable and less expensive technique to inoculate nursery seedlings with suitable type of inoculum with selected ectomycorrhizal fungi for their better survival, establishment, growth and yield of the species on their transplantation to the new areas or fields. This may also provide an alternate use of costly fertilizers and help in afforestation programme and reclamation of wasteland particularly mined overburdens, sand dunes and other adverse sites. Acacia auriculiformis and A. mangium have been identified as the most promising tree species for both plantation forestry and reforestation in the tropics and also used for wood pulp, sawn timber and wood for particle board. In the present study, an investigation was made to select suitable type of ectomycorrhizal inoculum for growth enhancement of commercially important Acacia tree species in nursery. Different types of inocula such as basidiospore inoculum, vegetative mycelial vermiculite based inoculum and alginate bead inoculum were applied to seedlings of Acacia spp. in nursery. Data on growth parameters such as shoot & root lengths, leaf numbers, collar diameter, fresh and dry weights of shoot and roots of both inoculated (with different types of ECM fungal inocula) and uninoculated (control) seedlings of Acacia auriculiformis and A. mangium were recorded. The results the study indicated that basidiospore and vegetative mycelial inocula of L. fraterna and some of the isolates of P. albus inoculated seedlings had greater growth performance than uninoculated (control) seedlings. Morphological and anatomical features of roots of both inoculated and uninoculated (control) seedlings of Acacia species were also studied for assessing the persistence of the inoculant ECM fungi. The seedlings inoculated with vegetative mycelial inoculum and basidiospore inoculum of P. albus revealed more mycorrhizal tips in the roots of Acacia spp. in sterilized (autoclaved) potting medium as compared to unsterilized potting medium. Significance of the findings is discussed.