Bacterial infections pose a significant global health burden, accounting for approximately 7.7 million deaths worldwide. Shockingly, this amounts to 1 in 8 of all global deaths, making it the second leading cause of death worldwide. While iodine and alcohol are commonly used for wound sterilisation, they have limitations such as high volatility, which hinders achieving a long-term antibacterial effect.
Additionally, inadequate awareness among individuals treating wounds can lead to infections and the development of chronic wounds. In recent times, there has been a growing focus on environmental protection, bringing the issue of plastic pollution to the forefront. In Hong Kong alone, nearly 2 thousand tons of plastic waste are disposed of in landfills every day, highlighting the urgent need for effective solutions.
Another concerning issue is the improper use of antibiotics and the alarming rise in antibiotic resistance. This has raised concerns among healthcare professionals and researchers alike.
In light of these challenges, our project aims to develop a disinfectant hydrogel plaster with a long-lasting sterilising effect.
Inspired by the use of black soldier fly larvae for the treatment of food waste, where their antimicrobial properties eliminate bad smells associated with bacterial growth, we aim to achieve this by harnessing the antimicrobial peptides (AMPs), namely DLP and CLP family peptides as our target for producing antimicrobial peptides, originated from Black Soldier Flies (BSFs). Our plaster is also made up of chitin extracted from BSF. It not only possesses potent antimicrobial properties but is also biodegradable, breaking down naturally within several weeks.
By combining innovative approaches, sustainable materials, and natural antimicrobial properties of BSF peptides, our project endeavours to make a meaningful contribution to combating the above issues while minimising the environmental impact.
We are currently addressing four pressing issues that have garnered public attention and pose threats to various life forms in our daily lives.
Chronic wounds are characterised by a failure to heal in a systematic manner within an expected timeframe. Various risk factors contribute to the development of chronic wounds, including infection, ageing, obesity, and other factors. The common bacteria that can cause chronic wounds include Staphylococcus aureus, Pseudomonas aeruginosa, and streptococci, among others. The global prevalence of chronic wounds is escalating due to the growing ageing population and increasing rates of diseases such as diabetes, obesity, and the long-term effects of radiation therapy. This has resulted in an epidemic of chronic wounds, posing significant challenges to healthcare systems.
Left untreated, chronic wounds can have profound effects on an individual's quality of life and may even necessitate limb amputation. Shockingly, approximately 30 percent of untreated chronic wounds eventually lead to amputation. It is estimated that in developed countries, 1 to 2 percent of the population will experience a chronic wound at some point in their lifetime. The impact of chronic wounds extends beyond the physical consequences, causing substantial emotional and psychological trauma to patients and their families. The burden of chronic wounds is not only measured in terms of mortality rates but also in the suffering endured by those affected.
Bacteria, a type of prokaryotic organism, is equipped with a unique characteristic in that they can exist as normal flora, colonising the human body without causing infection. However some will cause bacterial infection. Bacterial infections have a significant impact on public health as they can affect various parts of our body and disrupt the body's normal response. These infections can be transmitted through various mediums, including direct contact, contaminated food, airborne particles, droplets, and vectors such as insects. When a person becomes infected, bacteria have the potential to cause diseases.
Bacterial infections can affect our body. Different species of bacteria have tendencies to infect specific organs, such as the lungs, abdomen, heart valves, and virtually any other site. When an infection occurs, antibiotics are commonly used to suppress bacterial growth. However, it's crucial to note that the misuse or overuse of antibiotics can lead to the development of antibiotic-resistant strains, making treatment more challenging.
In some cases, bacterial infections can escalate and lead to sepsis, a life-threatening condition characterised by a systemic inflammatory response. Once the cascade of events leading to sepsis has begun, even the most potent antibiotics may be ineffective in stopping the progression of the infection. This highlights that efforts should be made promptly to mitigate this problem.
The emergence of multidrug-resistant bacteria due to the overuse and misuse of antibiotics poses a significant threat when it comes to treating bacterial infections. Antibiotics are commonly used to kill bacteria or disrupt their mechanisms, but their excessive and inappropriate use in medications, as well as in livestock and fish farming, has led to the development of antibiotic-resistant strains.
As we continue to use antibiotics, the chances of bacteria becoming resistant to antibiotics increase. Over time, bacteria undergo mechanisms of evolution, such as natural selection, allowing the resistant strains to survive and multiply, posing a grave risk to public health. This rise in antibiotic resistance is an urgent global public health concern, resulting in the deaths of at least 1.27 million people worldwide and being associated with nearly 5 million deaths in 2019 alone.
The existence of these superbug bacteria, which are incredibly difficult to eradicate, exacerbates the problem. Moreover, the skyrocketing rates of antibiotic resistance contribute to prolonged hospital stays, higher medical costs, and increased mortality rates.
Plastic pollution has reached alarming levels, with approximately 12.7 million tons of plastic entering the ocean each year and a staggering 400 million tons of plastic waste being generated annually. Plastics pose two distressing situations: their non-biodegradable nature and the release of harmful chemicals.
Plastics, being non-biodegradable, take an extended period to decompose. For instance, plastic straws can persist for up to 200 years, while plastic bottles may require up to 450 years to fully break down. Plaster has an even longer decomposition period, exceeding 500 years. Additionally, certain chemicals leach from plastics, particularly chlorinated plastics, which can disrupt hormonal systems in both vertebrates and invertebrates, posing risks to various organisms once they enter soil and water.
In soil ecosystems, discarded plastics degrade into microplastics that concentrate in high levels, leading to reduced abundance and changes in the community composition of soil fauna. This has significant ecological implications for soil communities at different trophic levels. In aquatic ecosystems, plastics threaten a wide range of organisms, including humans. Toxic chemicals found in plastics can cause cell damage, inflammation, and chronic diseases, affecting fertility in both men and women.
Marine plastics are estimated to contribute to the deaths of over 100,000 marine mammals annually. Aquatic creatures, such as sea turtles, often mistake plastics for food, leading to starvation and further harm to the food chain. In summary, plastic pollution poses significant environmental and health risks, necessitating immediate action to mitigate its impact.
Recently, antibiotic resistance has become a global concern. Our team aims to find an antibiotic alternative due to rising resistance. Given our expertise in using black soldier flies for odourless food waste recycling, we explored their potential as a source of antimicrobial peptides to replace antibiotics, such as DLP4. Our research involved various investigations, including literature review, modelling, and interviews with professors. We are incredibly grateful to the professors who generously shared their time and insights, as their input had a profound impact on the ethical and social considerations of our project.
These interviews emphasised the significance of ethical practices, addressed concerns about potential harm, and prompted us to reevaluate our project's approach to ensure economic feasibility and positive social outcomes. Consequently, we made modifications to our project drafts, demonstrating a deeper understanding and integration of ethical and social factors into our framework.
Among our investigations, the visit to the Black Soldier Fly farm was particularly inspiring. Initially, we held preconceived notions of these creatures being mossy, disgusting, and smelly. However, contrary to expectations, there was no pungent odour permeating the air at the farm.
One of the key roles of black soldier flies is their ability to act as decomposers. The larvae, in particular, excel at breaking down organic matter and transforming waste into a valuable resource. They thrive on a diet of fresh manure and various types of food waste, both animal and vegetable.
Moreover, black soldier flies play a vital role in nature's cleanup crew. As they consume and break down organic matter, they contribute to a less malodorous environment, providing a more human-friendly approach to managing food waste. Additionally, they pose no threat to humans. Notably, we discovered that chitin can be extracted from black soldier flies at different stages of their lifecycle, which can ultimately be converted into chitosan—a key ingredient in our design product.
Following the visit to the Black Soldier Fly farm, our project continued with various investigations, including modelling, in order to identify additional antimicrobial peptides similar to DLP4. We discovered promising candidates such as CLP1, CLP2, CLP3, DLP1, DLP2, and DLP3. By synthesising our research findings and incorporating advice from professors, we successfully created the first iteration of the "Antimicrobial Black Soldier Fly Ecoplaster."
The following properties and descriptions of black soldier flies have been identified through a comprehensive analysis of research papers, interviews, and a visit to a Black Soldier Fly farm.
The black soldier fly, scientifically known as Hermetia illucens, is a common fly found in outdoor environments near decomposing organic material such as animal waste or plant debris. These flies have gained attention for their potential in waste management and resource recovery.
Female black soldier flies exhibit a rapid reproduction rate, laying 206-639 eggs near decaying matter. The life cycle of black soldier fly consists of larval and adult stages. The larvae can grow up to 27 mm in length and complete their development in just 14 days, going through six instars. The adult soldier flies have a lifespan of 47-73 days and bear a resemblance to wasps in appearance.
One of the remarkable characteristics of black soldier fly larvae is their ability to outcompete houseflies and blowflies in decaying matter. This natural advantage reduces foul odours and enhances the efficiency of compost systems in decomposing food waste. We have also explored the use of antimicrobial peptides found in black soldier flies, such as CLP1, 2, 3 and DLP1, 2, 3, 4 as an alternative to antibiotics.
These larvae play a crucial role in waste management by efficiently converting various waste materials into valuable resources. Before entering the prepupal stage, the larvae go through six instars and then migrate towards cool, dark, and dry areas to pupate. This behaviour has been utilised in grub composting bins, which harness the larvae's migration to self-harvest mature specimens. By breaking down organic matter quickly, black soldier fly larvae contribute to waste reduction, reducing volume, weight, and releasing heat.
In summary, black soldier flies offer an eco-friendly and efficient solution to waste management and resource recovery. Their ability to convert waste into valuable resources, their outcompeting of other fly species, and the potential use of their antimicrobial properties and chitin make them a promising avenue for sustainable waste management practices.
While examining antimicrobial peptides in various insects, particularly within black soldier flies, is a common research topic, our team is pioneering the conversion of their antibacterial properties into a plaster product. We aspire for our newly designed and non-allergic plaster which includes two special features derived from black soldier flies to serve as an alternative to plastic-based plasters, aiming to address the aforementioned issues effectively.
Our project involved testing seven different antimicrobial peptides through an agar plate test, ultimately selecting the most potent antimicrobial peptide to be incorporated into our hydrogel plaster. This selected antimicrobial peptide demonstrates remarkable effectiveness in killing bacteria, thereby preventing bacterial infections that may arise due to incomplete sterilisation. This innovative approach offers a new method for managing chronic wounds.
Unlike traditional treatments involving wound dressings and bandages, which may be less efficient, the addition of antimicrobial peptides not only eliminates the need for saline solution but also accelerates the healing process of chronic wounds. Importantly, this novel plaster contributes to combating the concerning trend of antibiotic resistance by replacing the use of antibiotics in the treatment of bacterial infections. By harnessing the power of antimicrobial peptides, we can provide an alternative solution that addresses bacterial growth without contributing to the development of antibiotic resistance.
Overall, this hydrogel plaster represents a significant advancement in wound care, offering improved efficacy and the potential to mitigate the challenges posed by antibiotic resistance.
Undoubtedly, plastics have a significant environmental impact due to their slow decomposition process. However, our plasters present a stark contrast to conventional ones as they are made from chitin extracted from black soldier fly larvae, a polysaccharide that decomposes in a much shorter time frame of approximately 7 weeks. This property not only prevents the accumulation of plastics but also alleviates the burden on landfills. By offering an appealing alternative to traditional plasters, our chitin-based plasters can provide a brilliant solution.
In light of the urgent need to protect our environment, we strongly urge the public to take proactive steps in reducing plastic waste. By choosing environmentally friendly options like our chitin-based plasters, individuals can contribute to the preservation of our planet. Together, let us embrace sustainable alternatives and make a positive impact on the health of our ecosystems and future generations.
Our hydrogel plaster is specifically designed using chitin derived from the shed shells of black soldier flies during their life stages. Inspired by a visit to a black soldier fly farm in Lau Fau Shan, we are dedicated to establishing long-term collaborations with black soldier fly farms worldwide, ensuring the production of cost-effective plasters and providing alternatives which are more environmentally-friendly to the public. We would like to popularise the importance of the antibacterial function of plasters.
At the same time, we have been aware of the United Nations' call to action for global sustainability, known as the Sustainable Development Goals (SDGs). We are particularly focused on two of these goals:
The first goal is "Good health and well-being." By promoting the use of our plasters instead of traditional ones, we strive to reduce the number of deaths and illnesses caused by the issues previously mentioned. Moreover, our plaster possesses antimicrobial properties that can help combat the escalating threat of antibiotic resistance, which stems from bacterial infections and improper antibiotic use. This breakthrough can prevent the misuse of antibiotics and contribute to reducing mortality rates.
The second goal we focus on is "Responsible consumption and production." Our plaster takes advantage of the abundant chitin production and reproductive capabilities of Black Soldier Flies, effectively utilising natural resources and diverting a substantial amount of organic waste from landfills. Moreover, it can biodegrade within a few weeks, contributing to the reduction of waste generation.
Although we acknowledge the formidable challenges and missions ahead, it is reassuring to know that all the aforementioned problems can be alleviated if our plaster is successfully produced and effectively promoted to the public. Our project aims to provide an effective solution for wound sterilisation while minimising environmental impact.
