Development and Characterization of Pectin-Based Agar from Corchorus olitorius (saluyot) and Its Use for Isolation and Molecular Identification of Pectinase-Producing Microbes

The increasing demand for industrial enzymes necessitates sustainable and cost-effective production methods. Traditional approaches for detecting pectinase-producing microorganisms often rely on commercial substrates and chemical reagents, which can be expensive and environmentally concerning. This study investigated the potential of pectin extracted from Corchorus olitorius (saluyot) as a primary component in a minimal growth medium for isolating pectinase-producing microbes. Pectin was extracted from saluyot leaves and characterized for physicochemical properties (yield, color, odor, moisture content, solubility, pH, degree of esterification) and structural composition using Fourier Transform Infrared (FTIR) spectroscopy. Microorganisms were isolated from infected saluyot tissues and cultured on standard fungal media and a minimal medium prepared with the extracted pectin. Isolates were characterized morphologically and identified through DNA isolation, PCR amplification of the ITS region, and sequencing. The extracted pectin yielded 2.6% (w/w) of a light green, odorless powder with 2.25% moisture content, pH of 5.7, water solubility, and 74.5% degree of esterification, classifying it as high-methoxyl pectin. FTIR analysis revealed functional groups (alcohols, alkanes, carboxylic acids, ethers) consistent with commercial pectin. A fungal isolate cultivated on the pectin-based medium was identified through ITS sequencing as Aspergillus tritici (99% identity, E-value 0.0). The findings demonstrate that Corchorus olitorius yields pectin with physicochemical and structural properties suitable for microbiological media. The pectin-based agar successfully supported the cultivation of A. tritici, suggesting its potential as a cost-effective alternative substrate for isolating pectinase-producing fungi.