OPTIMIZATION OF THE EXTRACTION PROCESS FROM YELLOW CAMELLIA FLOWERS (CAMELLIA CUCPHUONGENSIS NINH & ROSMANN) COLLECTED IN PHU THO PROVINCE USING RESPONSE SURFACE METHODOLOGY. JMM-NIMM. 2026;31(1+2):pp. 96 - 104. doi:10.63240/jmm-nimm.2026.1+2.215