## 3 Results and Discussion  
### BC Productivity Parameters  
Figure 1 displays the PCA-Biplot on planes 1-2, indicating an accumulated inertia of 98.7%, generated using RStudio software, version 4.1.1 (R Core Team, Vienna, Austria). The figure illustrates three clusters for the Productivity Parameters of BC. The results demonstrate the normal distribution of 15 data points around three clusters. The cluster sizes correlate with the number of data points: Cluster 1 contains four points (green); Cluster 2 includes four points (purple); and Cluster 3 comprises seven points (red). Samples 1, 2, 3, and 4 (Cluster 1, green) exhibit a stronger association with the Substrate Conversion Ratio. Meanwhile, samples 5, 6, 7, and 8 (Cluster 2, purple) show a relationship with Weight and Yield, whereas samples 9 through 15 (Cluster 3, red) display no strong association with any parameter. Banana peel extracts at higher concentrations (T5, T6, T7, and T8) demonstrated a significant relationship with the variables Weight and Yield. These two variables are interrelated, as cellulose weight serves as the numerator in the yield calculation. Thus, an increase in cellulose weight enhances yield, provided that the maximum cellulose amount defined by the initial substrate concentration remains constant [19]. The banana peel extracts yielded the highest values in weight and yield due to their rich nutritional composition, which supported the growth and metabolic activity of the bacterial strain _Komagatezibacter hansenii_. Banana peels are a nutrient-dense substrate, primarily containing carbohydrates in the form of fermentable simple sugars like glucose, fructose, and sucrose, as well as complex carbohydrates, such as starch, that require enzymatic hydrolysis to become fermentable [27; 28]. Additionally, they are rich in essential minerals such as magnesium, potassium, and calcium, which function as enzymatic cofactors in various metabolic processes, along with vitamins that enhance growth and cellular activity [29; 30]. Banana peels also contain bioactive compounds like phenols and flavonoids, which stimulate the production of secondary metabolites, including cellulose [31]. Glucose, in particular, is abundant in banana peels and serves as a direct precursor in the cellulose synthesis pathway [32]. Thus, the high levels of nutrients and sugars accelerate bacterial growth rates, leading to increased biomass and cellulose production [33; 34]. High extract concentrations can optimize culture medium conditions by maintaining stable pH, osmolarity, and substrate availability. Banana peel extracts stabilize the pH during microbial growth and create an optimal osmotic environment for nutrient absorption [35]. Moreover, they contain fewer inhibitory compounds compared to other culture media, facilitating more efficient production [36]. Figure 1: Biplot for the productivity parameters of BC obtained from the 15 study treatments (T1–T15). The evaluated variables were weight (W), yield (Y), and substrate conversion ratio (SCR). In contrast, pineapple peel extracts did not yield favorable results in terms of Substrate Conversion Ratio, Weight, or Yield due to significant nutritional differences compared to banana peel. While pineapple peels are also rich in essential nutrients, including carbohydrates, minerals, and vitamins, and provide fermentable sugars and bioactive substances similar to banana peels, their nutritional composition is distinct [18; 37]. Pineapple peels contain higher amounts of the proteolytic enzyme bromelain, which is absent in banana peels; this enzyme breaks down proteins in the culture medium, thereby affecting the availability of nitrogen and other nutrients [38; 39]. Additionally, pineapple peels are more fibrous than banana peels, which impacts the proportions, availability, and types of simple sugars and complex carbohydrates, thus influencing the efficiency of the hydrolysis process [40].