Bioplastic - The Future is Degradable Plastics. Investigating Biodegradation of Polyhydroxybutyrate Bioplastic by 紐西蘭 Soil Microorganisms
The rate and production of conventional petroleum based plastics is unsustainable and not eco-friendly. Plastics often end up in marine environments and can take hundreds of years to decompose in landfills. According to Statistica, in 2015 alone, global plastic production was approximately 322 million metric tonnes and is projected to increase in the future. PHB bioplastic or Polyhydroxybutyrate is both biologically produced and biodegradable and can serve as a viable alternative to conventional plastics. But can it be broken down by soil microbes within a reasonable time frame? I have set out to answer this question. My aim was to isolate and analyse microorganisms from the Rotorua area that are capable of degrading Polyhydroxybutyrate (PHB) bioplastic . I isolated PHB degrading microorganisms from Rotorua soils by culturing on an agar based mineral salt media supplemented with PHB powder (MSM PHB agar). Samples were taken from Mount Ngongotaha and Te Puia geothermal soils as well as Okareka, termite frass and termite guts. One isolate from the Te Puia sample (labelled G2) was found to successfully degrade PHB powder. After isolation and purification of the G2 isolate, it was cultured on a range of media types to examine properties exhibited under differing nutrient conditions. Multiple organisms were found to be involved in the degradation of PHB bioplastic and work together symbiotically, this included bacteria and fungi which was identified as penicillium. The sample isolated from Te Puia soils (site 2 – G2Clear) in the Rotorua environment was found capable of competently degrading PHB, clearing 8% of PHB after 26 days. The G2Clear isolate is a mixture of bacteria and fungi working in an endosymbiotic relationship to degrade PHB and are unable to successfully degrade PHB individually. It is through the secretion of an extracellular PHB depolymerase enzyme that PHB is degraded, conforming with my hypothesis. This proves that PHB bioplastic is a viable alternative to conventional petroleum based plastics as PHB can be relatively quickly broken down by soil microorganisms.
Algae Meets Fungi: Microalgae-Fungi Co-Pelletization for Biofuel Production
Microalgae-fungi biofuel has significantly less CO2 emissions than fossil fuels, making it much more environmentally friendly. As well, unlike traditional biofuel, microalgae-fungi does not require large masses of agricultural land for production. Thus, microalgae-fungi is an optimal option for biofuel production. This is a cost-effective renewable energy source that can be used in place of regular gas in cars and other means of transportation. By determining the most effective fungi for biofuel production, the threat of the impending environmental damage from pollution can be diminished. This novel experiment determines which fungi: Aspergillus niger, Rhizopus stolonifer or Saccharomyces cerevisiae, is the most effective bioflocculant in the microalgae-fungi co-pelletization process for biofuel production. We hypothesize that when paired with the microalgae Chlorella vulgaris, Rhizopus stolonifer will be the most effective. It has a high lipid content which could enhance the overall production of biofuel. Furthermore, its negative charge will aid with attracting and neutralizing the C. vulgaris colloidal particles resulting in an easier and more efficient removal of microalgae particles. Through the process of bioflocculation, pelletization, esterification and transesterification, the most effective fungi paired with C. vulgaris was determined. This experiment was carried out thoroughly and precisely resulting in a cost-effective solution for the world's current pollution crisis.
Antibacterial Properties of Mānuka
Antibacterial Properties of Mānuka Mānuka (Leptospermum scoparium) is a native 紐西蘭 plant that has long been used by indigenous Maori for its medicinal and therapeutic properties, yet is relatively unknown to science. Many of our native species may contain novel compounds with practical applications in our lives. Research indicates that mānuka has anti-microbial, anti-fungal, herbicidal, insecticidal and anti-bacterial properties, and suggests that compounds similar to Grandiflorone (ß-triketones) cause these effects. This project investigates the antibacterial properties of mānuka leaves, using the bacteria Photobacterium phosphoreum for biological testing. With the recent rise in multidrug-resistant bacteria, it is now more vital than ever to utilize traditional knowledge to inform research and development of innovative new antibiotics, antimicrobials and similar biologically important compounds.