RECALCITRANT HALOCARBONS - Environmental Microbiology

This presentation explores the role of recalcitrant halocarbons in environmental microbiology, focusing on their persistence in ecosystems and the challenges they pose to microbial degradation. It covers the mechanisms by which certain halocarbons resist breakdown, their impact on soil and water quality, and the strategies employed by microbes to metabolize these stubborn compounds. The presentation also highlights current research, environmental concerns, and potential solutions for managing halocarbon contamination in various ecosystems. Ideal for students, researchers, and environmental professionals.

1. Sub Title: Food and Environmental Microbiology Sub Code: WMBM41 (Core) Title: Recalcitrant Halocarbons Here is where your presentation begins Submitted To ; Dr. S. Viswanathan, M.Sc, Ph.D., Head and Associate Professor, PG and Research Department of Microbiology, Sri Paramakalyani College, Alwarkurichi-627412. Submitted By ; Lakshmikanth Velmani , II, M.Sc, Microbiology, PG and Research Department of Microbiology, Sri Paramakalyani College, Alwarkurichi-627412. Seminar Assigned Date; 2 0-01-2025 Seminar Completion Date; 29-01-2025

2. “Striving for Excellence through Seminar” Aim By taking seminar, I Gain deeper understanding and insights into the topic, and to understand the significance of Recalcitrant Halocarbons in protecting the environment and promoting sustainable development. Objectives 1 . To gain in-depth knowledge and understanding of the seminar topic. 2. To comprehend the role of Recalcitrant Halocarbons in identifying and mitigating environmental impacts.
3. To analyze the contribution of EIA to remove Recalcitrant Halocarbons.
4. To remove the effectiveness of Recalcitrant Halocarbons environmental protection.

3. SYNOPSIS XENOBIOTICS HALOCARBONS ENVIRONMENTAL IMPACTS MICROBIAL DEGRADATION OF RECALCITRANT HALOCARBONS ROLE OF PSEUDOMONAS AERUGINOSA IN PCB BREAKDOWN FACTORS INFLUENCING DEGRADATION EFFICIENCY REGULATION AND MANAGEMENT OF RECALCITRANT HALOCARBONS CONCLUSION REFERENCES

4. Xenobiotic compounds are man-made synthetic substances that are available in the climate at unnaturally high fixations. Microorganism has the capacity of corrupting all normally happening compounds; this is known as the standard of microbial reliability proposed by Alexander in 1965. XENOBIOTICS

5. The xenobiotic mixtures might be stubborn because of at least one of the accompanying reasons: (I) They are not perceived as substrate by the current degradative chemicals, (ii) They are profoundly steady, i.e., synthetically and organically dormant because of the presence of replacement bunches like incandescent light, nitro-, sulphonate, amino-, methoxy and carbamyl gatherings, (iii) They are insoluble in water, or are adsorbed to outside networks like soil, (iv) They are profoundly toxic or lead to poisonous items because of microbial action,

6. XENOBIOTICS

7. Properties of xenobiotic compounds (Foti and Dalvie 2016): 1. They are extremely stable in nature and insoluble in water. 2. Degradative microorganisms do not recognize them as substrate. 3. They are extremely toxic and contain large molecular weight that checks entrance into microbial cells. Xenobiotic compound find many application in our day to day lives such as food additives, drugs or pesticides. On the other hand they are harmful towards nature and health as environmental pollutants like dioxins, furans and carcinogen.

8. Structural features of xenobiotic compounds

9. This Photo by Unknown Author is licensed under CC BY

10. Halocarbons These mixtures contain various quantities of halogen (e.g., CI, Br, F (fluorine), I) iotas in the spot of H molecules. They are utilized as solvents (chloroform, CHCI3), as charges in shower jars of beauty care products, paints and so on, in condenser units of cooling frameworks (Freons, CCI3F, CCl2F2, CClF3, CF4), and as bug sprays (DDT, BHC, lindane and so forth) and herbicides ( dalapon , 2, 4-D, 2, 4, 5-T and so on)

11. Recalcitrant halocarbons are a group of synthetic organic compounds that contain carbon, hydrogen, and halogen atoms.

12. Recalcitrant halocarbons are defined as compounds that are resistant to degradation and persist in the environment for extended periods.

13. Introduction to Recalcitrant Halocarbons Definition and Origin Class of synthetic organic compounds. Halogen atoms (fluorine, chlorine, bromine, or iodine) Resistant to degradation in the environment. origination from industrial processes, including manufacturing of pesticides, refrigerants, and solvents. Persistence and Bioaccumulation Their unique chemical structure grants them exceptional persistence, meaning they remain intact in the environment for extended periods. This persistence, coupled with their lipophilic nature, leads to bioaccumulation in organisms, posing a significant threat to ecological health.

14. Examples of Recalcitrant Halocarbons

15. Properties and Characteristics

16. Environmental Impacts

17. Environmental Concerns and Impacts Soil and Water Contamination These compounds can contaminate soil and water bodies, harming ecosystems and impacting the health of organisms that rely on these resources. Their persistence makes clean-up difficult and costly, requiring specialized remediation techniques. Bioaccumulation and Food Chain Impacts Due to their lipophilic nature, recalcitrant halocarbons accumulate in organisms, magnifying their concentration at higher trophic levels. This bioaccumulation can disrupt biological processes, affecting the health and survival of wildlife and potentially posing risks to human health through consumption of contaminated food sources. Ozone Depletion and Climate Change Certain recalcitrant halocarbons, particularly those containing chlorine, are known to contribute to ozone depletion in the stratosphere, leading to increased ultraviolet radiation reaching the Earth's surface. They can also act as greenhouse gases, trapping heat and exacerbating climate change.

18. Microbial Degradation of Recalcitrant Halocarbons 1 Bioaugmentation Enhancing the microbial population in contaminated environments through the introduction of specific microbial strains or consortia that possess the ability to degrade recalcitrant halocarbons. This approach relies on the metabolic capabilities of specialized microorganisms to break down the contaminants. 2 Biostimulation Modifying environmental conditions, such as oxygen availability, nutrient levels, and pH, to stimulate the growth and activity of indigenous microbial populations already present in the contaminated environment, promoting their ability to degrade recalcitrant halocarbons. 3 Bioremediation A comprehensive approach that encompasses both bioaugmentation and biostimulation, aiming to optimize the conditions for microbial degradation of recalcitrant halocarbons. This involves careful selection of microorganisms, optimization of environmental factors, and monitoring the degradation process over time.

19. Role of Pseudomonas aeruginosa in PCB Breakdown 1 Initial Attack Pseudomonas aeruginosa initiates the degradation process by utilizing specific enzymes that can break the carbon-chlorine bonds in PCBs, releasing chlorine atoms and forming less chlorinated intermediates. This step is crucial for initiating the breakdown of the recalcitrant molecules. 2 Oxidative Transformation Through a series of enzymatic reactions, the less chlorinated intermediates undergo further oxidation, leading to the formation of various metabolites, including alcohols, ketones, and aldehydes. These metabolites are generally more readily biodegradable than the original PCBs. 3 Final Degradation The final degradation steps involve the conversion of these metabolites into smaller, non-toxic molecules, such as carbon dioxide, water, and chloride ions. This process effectively removes the harmful PCBs from the environment, reducing their environmental impact.

20. Factors Influencing Degradation Efficiency Temperature Microbial activity is temperature-dependent, with optimal ranges for enzyme activity. Temperatures outside this range can reduce enzyme activity, slowing down the degradation process. pH The pH of the environment influences the activity of microbial enzymes, affecting their ability to break down recalcitrant halocarbons. Specific pH ranges are optimal for the enzymes involved in the degradation process. Oxygen Availability Many microorganisms involved in degradation require oxygen for their metabolic processes. Oxygen availability is crucial for the efficient breakdown of recalcitrant halocarbons, as it provides the necessary electron acceptor for oxidation reactions. Nutrient Availability Microbial growth and activity are dependent on the availability of essential nutrients, including nitrogen, phosphorus, and trace elements. Adequate nutrient levels are necessary for optimal microbial degradation of recalcitrant halocarbons.

21. Extraction and Analysis of PCBs from Wastewater Sampling Wastewater samples are collected from various sources, such as industrial effluent, municipal wastewater, and contaminated water bodies. Sampling techniques are crucial to ensure representative samples that accurately reflect the concentration of PCBs in the wastewater. Extraction Different extraction methods are employed to isolate PCBs from the wastewater matrix, including liquid-liquid extraction, solid-phase extraction, and supercritical fluid extraction. The choice of method depends on the nature of the wastewater and the specific characteristics of the PCBs. Purification Extracted PCBs are often further purified to remove interfering compounds and concentrate the analytes. Techniques such as column chromatography and distillation are used to achieve the desired level of purity for accurate analysis. Analysis Purified PCB extracts are analyzed using sophisticated analytical techniques, such as gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC), to identify and quantify the specific PCB congeners present in the samples.

22. Health Impacts

23. Sources and Pathways

24. Potential Applications and Remediation Strategies 1 Bioremediation Leveraging the power of microorganisms to break down recalcitrant halocarbons, either by introducing specialized strains or optimizing conditions for existing populations. 2 Activated Carbon Adsorption Removing PCBs from contaminated water or air by passing the stream through a bed of activated carbon, which physically adsorbs the pollutants onto its surface. 3 Chemical Oxidation Using strong oxidants, such as ozone or hydrogen peroxide, to chemically break down PCBs into less harmful substances. This method can be effective for treating contaminated water and soil. 4 Phytoremediation Utilizing plants to absorb and accumulate PCBs from contaminated soil or water. Certain plants have a high capacity to absorb and metabolize these pollutants, contributing to environmental cleanup.

25. Regulation and Management

26. Challenges and Future Directions

27. Conclusion Recalcitrant halocarbons pose significant environmental and health risks, but through regulation, management, and innovation, we can mitigate these impacts and create a more sustainable future

28. References https://www.slideshare.net/slideshow/microbial-degradation-of-recalcitrant-compounds/235530101 https://www.slideshare.net/slideshow/biodegradation-of-xenobiotics-pptx/270644369 https://lms.su.edu.pk/download?filename=1619507582-recalcitrant-molecules.pptx&lesson=55803 https://www.biologydiscussion.com/microbiology-2/bioremediation/xenobiotic-compounds-meaning-hazards-and-biodegradation/55625

29. References

30. 1. Boosts my confidence in communicating complex ideas and opinions.
2. Helps me develop critical thinking and self-reflection skills, making me a more informed and thoughtful individual.
1. Enhances my time management and organizational skills as I prepare and deliver the seminar.
2. Allows me to receive constructive feedback and criticism, helping me to identify areas for improvement and grow both academically and personally. 1. Recognize the relevance and application of the seminar topic in various contexts.
2. Synthesize information from various sources to deepen understanding of the topic.
3. Develop a nuanced perspective on the seminar topic through critical reflection.
4. Articulate implications and consequences of concepts and ideas related to the topic. “Learning Outcomes” “Empowering my Potential”

31. SWOT Analysis Opportunities 1. Integration with sustainable development goals
2. Advances in technology
3. Increased public awareness
4. Capacity building and training Threats 1. Lack of political will
2. Limited resources
3. Conflicting interests
4. Climate change and uncertainty Strengths 1. Proactive approach
2. Holistic consideration
3. Improved decision-making
4. Enhanced public participation Weaknesses 1. Time-consuming and costly
2. Limited scope
3. Subjective interpretations
4. Inadequate enforcement

32. Moral Story Once, there was a small pond where animals and birds came to drink water. Over time, people started dumping waste into the pond. The water became dirty, and the animals stopped visiting. One day, a young boy decided to clean the pond. He removed all the trash, and slowly, the water became clear again. Soon, the animals returned. Moral: "Keep your surroundings clean for a healthy environment."