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A Preliminary Study on the Potential Biodegrading Ability POSTER_______

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A Preliminary Study on the Potential Biodegrading Ability POSTER_______ Powered By Docstoc
					                A Preliminary Study on the Potential Biodegrading Ability of Xylaria sp.
                     on Natural Rubber, Chicken Feather and Polystyrene through
                                    Scanning Electron Microscopy
                                                                               Janine Erica P. Dayao1 and Mary Bernadette V. Egloso1,
                                                                                  Anna Theresa A. Santiago1 and Mary Ann T. Tavanlar2
                                                   1Department   of Biology, College of Arts and Sciences, University of the Philippines Manila, Padre Faura St., Ermita, Manila
                                                    2National Institute of Molecular Biology and Biotechnology, University of the Philippines Los Baños, College Laguna 4031



  ABSTRACT
                                                                                                                                                                              CHICKEN FEATHER
 The potential biodegrading ability of the Xylaria sp. strains on three pollutants, namely, natural rubber, chicken
 feather and polystyrene were determined in terms of colonization. The fungal strains namely the wild type, SDM
 (sterile dark mycelia) and the five mutant strains (PNL 114, PNL 116, PNL 118, E26 and E35) were cultured in a
 pH 5.0 mineral medium with 0.5% glucose as carbon source, while the 3 pollutant substrates as co-carbon
 source, and stored at 250C. Scanning Electron Microscopy (SEM) revealed colonization of Xylaria sp. strain on
 the three pollutants. Generally, the black strains, namely the SDM wild type, E26 and E35, have been observed
 to possess a higher potential to biodegrade natural rubber, chicken feather and polystyrene than the albino
 mutants PNL 114, 116 and 118. The black variant strain E26 has shown the greatest biodegrading potential for
 biodegrading natural rubber. Polystyrene was effectively colonized by all strains. Chicken feathers were
 colonized by the SDM and E35 but may require a longer incubation period for degradation.


  INTRODUCTIION                                    METHODOLOGY
       Pollution caused by improper waste
disposal burdens third world countries like
the Philippines. It is high time to revert to
natural processes, such as biodegradation,
to solve this problem. Biodegradation is the
breakdown and utilization of waste as
source of nutrients through the enzymatic
action of microorganisms. In Mt. Makiling a
fungus named Xylaria sp. was identified
and      characterized      to     biodegrade
polyethylene plastic. The potential ability of
these fungal strains to biodegrade other
wastes, such natural rubber, chicken
feathers and polystyrene, were tested in
this study. Results would serve as source of
preliminary information on the potential of
this fungus to biodegrade. Furthermore, the
findings would provide data on the
characteristics of these fungal strains.


    RESULTS
   LEGEND: my=mycelia hy=hypha sp=spores st=striation
           tr=tearing c=crack r=rachis br=barb bl=barbule
           p=residual polystyrene mc=mycelia

                                                    NATURAL RUBBER




                                                                                                                                                                                                All strains efficiently colonized the samples, but
                                                                                                                                                                                                only SDM and E35 showed signs of degradation
                                                                                                                                                                                                such as weakened barbs and slightly brittle
                                                                                                                                                                                                barbules which detached from their barbs.




                                                                                                                                                                                 POLYSTYRENE




                                                                       Generally, the black strains specially strain E26, showed
                                                                       the greatest biodegrading potential as compared to the
                                                                       albino strains PNL 114, 116 and 118.




DISCUSSION
        Natural rubber, polystyrene and chicken feather were utilized as co-substrates of glucose for the growth of Xylaria sp.
Mycelia closely adhered to their surface and grew into it, thereby rendering their removal very difficult. Due to this, the change
in weight was not measured. Thus, weight gain is indicative of colonization, whereas weight loss is indicative of biodegradation.
The 0.5% glucose provided in the medium initiated and sustained growth for up to 3 weeks. Beyond this period when glucose
has been depleted, Xylaria sp. had to utilize the provided substrate as an alternative carbon source.
        After incubation, the set-ups were covered by mycelia. Such colonization and surface adhesion is a fundamental
prerequisite to biodegradation, although growth on a polymer surface is not adequate to deduce that carbon from this polymer
has been assimilated. Nonetheless, this colonization provides a simple, fast and clear test to evaluate the response of a
macromolecular material to biodegradation.
        Gentle scraping was done after removal of fungi from the samples to avoid surface destruction and to further remove
mycelia. Hence, the colonization seen under SEM cannot be attributed to mere mycelial aggregation on the surface since
physical manipulation was done.
        Most samples were covered by a slimy mucilaginous sheath or biofilm which can be easily removed. All strains tested in
this study are able to form biofilm, which is a crucial step to microbially induced biodegradation. A study hypothesized that after
                                                                                                                                                                                              Polystyrene was the most extensively colonized
adhesion, solubilizing agents are secreted by microorganisms which can make use of water-immiscible compounds.
                                                                                                                                                                                              substrate. SEM results of the albino mutants were
       The denser and thicker mycelial growth and more efficient performance of the black strains SDM wild type, E26 and E35
                                                                                                                                                                                              not widely different from the black strains.
than the albino mutants (PNL 114, 116 and 118) is due to the melanin cover of their hyphal surfaces. Melanin protects their
hyphae thus making them resistant to frictional damage during penetration into the substrate. The pollutants were weakened in
resistance and durability due to mycelial penetration.


CONCLUSION                                                                                                                            ACKNOWLEDGMENT
       Generally, the black strains, namely the SDM wild type, E26 and E35, have been observed to possess a higher potential to              The proponents of this study would like to thank the Antibiotic Laboratory at the National Institute of
biodegrade natural rubber, chicken feather and polystyrene than the albino mutants PNL 114, 116 and 118. Among the black              Molecular Biology and Biotechnology (BIOTECH) for providing the culture media, equipment and the Xylaria
variant strains, E26 has shown the greatest biodegrading potential for natural rubber, nonetheless the albino mutants also            sp inocula and the National Institute of Engineering at the University of the Philippines Diliman for the
showed a potential to biodegrade this substrate. Polystyrene was effectively colonized by the three black strains SDM wild type,      processing of our samples under the scanning electron microscopy (SEM).
E26 and E35, nonetheless the albino mutants also showed potential ability to biodegrade this substrate. Chicken feathers were
colonized by the SDM and E35 but may require a longer incubation period for degradation.
                       A Preliminary Study on the Potential Biodegrading Ability of Xylaria sp.
                            on Natural Rubber, Chicken Feather and Polystyrene through
                                           Scanning Electron Microscopy

                                                                                   Janine Erica P. Dayao1 and Mary Bernadette V. Egloso1,
                                                                                      Anna Theresa A. Santiago1 and Mary Ann T. Tavanlar2
                                                       1Department   of Biology, College of Arts and Sciences, University of the Philippines Manila, Padre Faura St., Ermita, Manila
                                                        2National Institute of Molecular Biology and Biotechnology, University of the Philippines Los Baños, College Laguna 4031




    ABSTRACT                                                                                                                  METHODOLOGY
     The potential biodegrading ability of the Xylaria sp. strains on three pollutants, namely, natural
     rubber, chicken feather and polystyrene were determined in terms of colonization. The fungal
     strains namely the wild type, SDM (sterile dark mycelia) and the five mutant strains (PNL 114,
     PNL 116, PNL 118, E26 and E35) were cultured in a pH 5.0 mineral medium with 0.5% glucose as
     carbon source, while the 3 pollutant substrates as co-carbon source, and stored at 250C. Scanning
     Electron Microscopy (SEM) revealed colonization of Xylaria sp. strain on the three pollutants.
     Generally, the black strains, namely the SDM wild type, E26 and E35, have been observed to
     possess a higher potential to biodegrade natural rubber, chicken feather and polystyrene than the
     albino mutants PNL 114, 116 and 118. The black variant strain E26 has shown the greatest
     biodegrading potential for biodegrading natural rubber. Polystyrene was effectively colonized by
     all strains. Chicken feathers were colonized by the SDM and E35 but may require a longer
     incubation period for degradation.’



    INTRODUCTIION
      Pollution caused by improper waste disposal burdens third world countries like the Philippines. It is high
      time to revert to natural processes, such as biodegradation, to solve this problem. Biodegradation is the
      breakdown and utilization of waste as source of nutrients through the enzymatic action of microorganisms.
      In Mt. Makiling a fungus named Xylaria sp. was identified and characterized to biodegrade polyethylene
      plastic. The potential ability of these fungal strains to biodegrade other wastes, such natural rubber,
      chicken feathers and polystyrene, were tested in this study. Results would serve as source of preliminary
      information on the potential of this fungus to biodegrade. Furthermore, the findings would provide data on
      the characteristics of these fungal strains.




 RESULTS
LEGEND: my=mycelia hy=hypha sp=spores st=striation tr=tearing c=crack r=rachis br=barb
        bl=barbule p=residual polystyrene mc=mycelia




                         NATURAL RUBBER                                                                               CHICKEN FEATHER                                                                                POLYSTYRENE




                                          Generally, the black strains specially                                                     All strains efficiently colonized the samples,
                                                                                                                                     but only SDM and E35 showed signs of                                                      Polystyrene was the most extensively
                                          strain   E26,    showed    the   greatest
                                                                                                                                     degradation such as weakened barbs and                                                    colonized substrate. SEM results of the
                                          biodegrading potential as compared to
                                                                                                                                     slightly brittle barbules which detached                                                  albino mutants were not widely different
                                          the albino strains PNL 114, 116 and 118.
                                                                                                                                     from their barbs.                                                                         from the black strains.



   DISCUSSION
 Natural rubber, polystyrene and chicken feather were utilized as co-substrates of glucose for the growth of Xylaria sp. Mycelia closely adhered to their surface and grew into it, thereby rendering their removal very difficult. Due to this, the change in weight
 was not measured. Thus, weight gain is indicative of colonization, whereas weight loss is indicative of biodegradation. The 0.5% glucose provided in the medium initiated (Cuevas & Manaligod, 1997; Clutario & Cuevas, 2001) and sustained growth for up to
 3 weeks (M. A. Tavanlar, personal communication, March 4, 2009). Beyond this period when glucose has been depleted, Xylaria sp. had to utilize the provided substrate as an alternative carbon source. After incubation, the set-ups were covered by mycelia.
 Such colonization and surface adhesion is a fundamental prerequisite to biodegradation, although growth on a polymer surface is not adequate to deduce that carbon from this polymer has been assimilated. Nonetheless, this colonization provides a simple,
 fast and clear test to evaluate the response of a macromolecular material to biodegradation (Clutario & Cuevas, 2001; Motta,et al., 2007). Gentle scraping was done after removal of fungi from the samples to avoid surface destruction and to further remove
 mycelia. Hence, the colonization seen under SEM cannot be attributed to mere mycelial aggregation on the surface since physical manipulation was done. Most samples were covered by a slimy mucilaginous sheath or biofilm which can be easily removed.
 All strains tested in this study are able to form biofilm (M. A. Tavanlar, personal communication, March 4, 2009), which is a crucial step to microbially induced biodegradation. A study (Reddy, et al., 1982; Gutnick & Minas, 1987) hypothesized that after
 adhesion, solubilizing agents are secreted by microorganisms which can make use of water-immiscible compounds (Clutario & Cuevas, 2001). The denser and thicker mycelial growth and more efficient performance of the black strains SDM wild type, E26
 and E35 than the albino mutants (PNL 114, 116 and 118) is due to the melanin cover of their hyphal surfaces. Melanin protects their hyphae thus making them resistant to frictional damage during penetration into the substrate. The pollutants were
 weakened in resistance and durability due to mycelial penetration.



   CONCLUSION                                                                                                                        ACKNOWLEDGMENT
 Generally, the black strains, namely the SDM wild type, E26 and E35, have been observed to possess a higher potential to           The proponents of this study would like to thank the Antibiotic Laboratory at the National Institute of Molecular Biology and
 biodegrade natural rubber, chicken feather and polystyrene than the albino mutants PNL 114, 116 and 118. Among the
                                                                                                                                    Biotechnology (BIOTECH) for providing the culture media, equipment and the Xylaria sp inocula and the National Institute of
 black variant strains, E26 has shown the greatest biodegrading potential for natural rubber, nonetheless the albino                Engineering at the University of the Philippines Diliman for the processing of our samples under the scanning electron
 mutants also showed a potential to biodegrade this substrate. Polystyrene was effectively colonized by the three black             microscopy (SEM).
 strains SDM wild type, E26 and E35, nonetheless the albino mutants also showed potential ability to biodegrade this
 substrate. Chicken feathers were colonized by the SDM and E35 but may require a longer incubation period for
 degradation.
                NATURAL                           CHICKEN
                              POLYSTYRENE
                RUBBER                            FEATHER




                   AGITATION w/ EtOH and                       SURFACE
                                               AUTOCLAVE
                      STERILE WATER                         STERILIZATION

SDM Wild type
  PNL 114
  PNL 116
                 XYLARIA        MINERAL MEDIUM
  PNL 118
                SP. STRAIN        w/ GLUCOSE
                                                      FUNGAL INOCULATION
    E26
    E35

                                    50 DAY
                                  INCUBATION



                                DECANT & GENTLE     CLEANING OF SUBSTRATE
                                   SCRAPING              OF MYCELIA


                              SCANNING ELECTRON
                                 MICROSCOPY