## 5 Conclusions  
The MAE conditions were successfully optimized to maximize the production of polyphenol-rich crude extracts from _Cinnamomun iners_ leaves. Using a three-variable FCCD and RSM, the MAE process yielded a reliable second-order polynomial model, demonstrating the effectiveness of the optimization approach. MAE optimal conditions (25 min, 214.24 W, 1:195.76 g/mL) resulted in predicted values of 18.56% for yield, 22.86 mg GAE/g for TPC, 13.89 mg QE/g for TPC, and an IC\({}_{50}\) of 83.30 ug/mL for DPPH scavenging activity. MAE efficiently enhances heat and mass transfer through internal microwave heating, rapidly releasing polyphenols. In contrast, the slower, prolonged heating in HRE yields lower antioxidant and polyphenol concentrations after 25 min. This highlights the efficacy of MAE, as microwave-driven heating disrupts cell walls, rapidly releasing compounds and enhancing antioxidant activity. The MAE conditions developed are ideal for producing polyphenol-rich crude extracts from cinnamon leaves, making them valuable in functional foods, industrial applications, and skincare formulations in the cosmetic industry. However, the batch-scale setup used in this study does not fully address the challenges of industrial-scale processing. Investigating the feasibility of scaling up the process using continuous-flow microwave extraction systems represents a potential avenue for future research, to address industrial production requirements. These advancements, combined with the extracts' antioxidant synergy, position MAE as a promising method for scale-up applications in functional foods and cosmetics. Conceptualization, PS. ; methodology, W.B. and T.S. ; software, S.L. ; validation, P.S. and K.T. ; investigation, P.S. ; resources, K.T. ; writing--original draft preparation, P.S. ; writing--review and editing, P.S; supervision, P.S. ; funding acquisition, P.S. All authors have read and agreed to the published version of the manuscript. This research was supported by King Mongkut's University of Technology North Bangkok under Contract No. KMUTNB-65-KNOW-29. Not applicable. The authors declare no conflicts of interest. This research was supported by [PERSON]'s University of Technology North Bangkok, for providing instrument support. This research was supported by [PERSON]'s University of Technology North Bangkok, for providing instrument support. * [PERSON] et al. (2022) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Microwave-Assisted Extraction of Anticancer Flavonoid, \(2^{\prime}\),\(4^{\prime}\)-Dihydroxy-\(6^{\prime}\)-Methoxy-\(3^{\prime}\),\(5^{\prime}\)-Dimethyl Chalcone (DMC), Rich Extract from _Syzgium nervousum_ Fruits. _Molecules_**2022**, _27_, 1397. [CrossRef]
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