*Article* **Microbial Poly(hydroxybutyrate-co-hydroxyvalerate) Scaffold for Periodontal Tissue Engineering**

**Seubsakul Phuegyod 1,† , Sasivimon Pramual 2,† , Nungnit Wattanavichean <sup>3</sup> , Supasuda Assawajaruwan 1, Taweechai Amornsakchai 4, Panithi Sukho 5, Jisnuson Svasti <sup>2</sup> , Rudee Surarit 6,7 and Nuttawee Niamsiri 1,\***


**Abstract:** In this study, we fabricated three dimensional (3D) porous scaffolds of poly(hydroxybutyrateco-hydroxyvalerate) with 50% HV content. P(HB-50HV) was biosynthesized from bacteria *Cupriavidus necator* H16 and the in vitro proliferation of dental cells for tissue engineering application was evaluated. Comparisons were made with scaffolds prepared by poly(hydroxybutyrate) (PHB), poly(hydroxybutyrate-co-12%hydroxyvalerate) (P(HB-12HV)), and polycaprolactone (PCL). The water contact angle results indicated a hydrophobic character for all polymeric films. All fabricated scaffolds exhibited a high porosity of 90% with a sponge-like appearance. The P(HB-50HV) scaffolds were distinctively different in compressive modulus and was the material with the lowest stiffness among all scaffolds tested between the dry and wet conditions. The human gingival fibroblasts (HGFs) and periodontal ligament stem cells (PDLSCs) cultured onto the P(HB-50HV) scaffold adhered to the scaffold and exhibited the highest proliferation with a healthy morphology, demonstrating excellent cell compatibility with P(HB-50HV) scaffolds. These results indicate that the P(HB-50HV) scaffold could be applied as a biomaterial for periodontal tissue engineering and stem cell applications.

**Keywords:** polyhydroxyalkanoates; poly(hydroxybutyrate-co-hydroxyvalerate); tissue engineering; 3D porous scaffolds; human gingival fibroblasts; periodontal ligament stem cells
