## 6 Challenges and Future Perspectives  
As industries try to find ways to become more environmentally friendly, the reutilization of the waste generated from different processes is pivotal. Avocado waste extracts have been widely studied, showing potential as natural food additives as well as interesting pharmaceutical properties. To the extent of our knowledge, there are no studies or clinical trials that describe the effects of bioactive compounds extracted from avocado byproducts on human health, therefore emphasizing the need for more thorough research on the safety of utilizing these extracts for human consumption. However, there have been some clinical trials that evaluated the effects of phenolic compounds from other medicinal plants on human health [106]. [PERSON] et al. carried out a phase I study of the topical application of epigallocatechin-3-gallate (EGCG) in patients with breast cancer to treat radiation dermatitis. A total of 24 patients were enrolled, and no acute toxicity was related to the treatment, and the reported symptoms of radiation dermatitis decreased after 2 weeks of treatment, proving that the treatment was well tolerated and effective [107]. [PERSON] et al. also had previously carried out a phase I study of the oral administration of EGCG in patients with advanced stage III lung cancer and observed significant regression of seophagitis to grade 0/1 in most patients, concluding that the oral administration of EGCG is feasible, safe and effective [108]. [PERSON] et al. studied the effects of tea polyphenols on prostate cancer. Twenty-six men with positive prostate biopsies were given daily doses of polyphenol E, which contained EGCG, epicatechin, epigallocatechin, epicatechin-3-gallate, and led to a significant decrease in serum levels of PSA, HGF, and VEGF, supporting the potential role of polyphenol E in the treatment of prostate cancer [109]. Other polyphenols, such as anthocyanins and resveratrol, have also exhibited antidiabetic properties by reducing blood glucose and improving glycemic control, respectively [110]. There are still several breaches in research that need to be further studied when it comes to the effects of polyphenols on human health, such as the different factors that can affect the bioavailability and bioactivity of polyphenols [111]. Few authors have studied the techno-economic feasibility of scaling up these extraction technologies at an industrial level. [PERSON] et al. studied the techno-economic evaluation of the extraction process of starch from avocado seeds, and concluded that it is an economically feasible process, and estimated a rate of return of 75%, a break-even analysis of 82% and a 2-year payback period, demonstrating that these sustainable technologies can be profitable at an industrial level [112]. [PERSON] et al. modeled and studied techno-economic feasibility of a biorefinery based on avocado waste. Using Aspen Plus v12.1 software, the authors modeled, simulated and optimized an avocado waste biorefinery, which could potentially achieve a gross profit of 3.7 \(\times\) 10\({}^{7}\)USD/year for capital costs of USD 30.7 \(\times\) 10\({}^{6}\) operating in optimal conditions. These results prove that it is possible for industries to take advantage of these agro-industrial residues in a sustainable and profitable way [113]. Nevertheless, there should be more focus on modeling and studying the economic feasibility of these technologies at an industrial level, especially for food and pharmaceutical applications. There are many limitations that can be associated with these technologies for utilizing these agro-industrial residues, starting with the fact the waste requires delicate handling to ensure its quality, which can be a challenge for small-scale producers. In addition, waste can vary in composition and quantity, making it difficult for industries to standardize procedures, and the regulations around the utilization of avocado waste to produce functional products are still not clear and are continuously evolving.