Acta Univ. Agric. Silvic. Mendelianae Brun. 2025, 73(4-5), 229-241 | DOI: 10.11118/actaun.2025.016

L(+)-Lactic Acid Production from Corncob Biomass using Multiple Parallel Fermentation (MPF) with Aspergillus spp. and Lactococcus lactis

Elya Mufidah¹, Audrya Nasywa Veliska¹, Adib Maula Mifzal¹, Farida Rahayu², Maghfira Selia Irawati³, Yusuf Wibisono¹, Sri Suhartini⁴, Maharani Pertiwi Koentjoro⁵

¹ Bioprocess Engineering Study Program, Department of Biosystem Engineering, Faculty of Agricultural Technology, University of Brawijaya, Malang 64145, Indonesia

² Research Center for Applied Microbiology, National Research and Innovation Agency, Bogor, 16911, Indonesia

³ Biology Study Program, Faculty of Mathematics and Natural Sciences, University of Brawijaya, Malang 64145, Indonesia

⁴ Department of Agricultural Industry Technology, Faculty of Agricultural Technology, University of Brawijaya, Malang 64145, Indonesia

⁵ Postgraduate School, Universitas Brawijaya, Malang 64145, Indonesia

Corncob is an abundant lignocellulosic residue whose conversion to high-value chemicals remains challenging. Here, we report the first Multiple Parallel Fermentation (MPF) that couples Aspergillus niger ATCC 16888, Aspergillus flavus ATCC 26946 and Lactococcus lactis ATCC 19435 in one pot for L-(+)- lactic acid production. The fungi supplied complementary cellulase- and xylanase-rich enzyme suites, while LAB rapidly fermented the released sugars. Enzyme activities, consortium compatibility and fermentation conditions were systematically optimized through Taguchi design (temperature 35-39 °C, pH 6.0-7.0, substrate 3-7%). The optimum setting-39 °C, pH 6.0, 7% corncob-yielded 1.783% w/v optically pure L-lactate in 48 h, outperforming earlier corncob processes by 19-55%. ANOVA assigned ~81% of the variance to temperature, confirming its dominant role, whereas substrate concentration and pH accounted for 14% and 4%, respectively. This is the first dual-fungus MPF on corncob. The dual-fungus strategy thus maintains a steady monosaccharide pool that sustains rapid LAB metabolism. Single-step MPF shortens processing time, avoids chemical hydrolysis and valorizes agricultural waste, offering a scalable route to food-grade L-lactic acid and PLA precursors within a circular-bioeconomy framework.

Keywords: Aspergillus flavus, Aspergillus niger, Corncob biomass; L(+)-Lactic acid, Lactococcus lactis, Multiple Parallel Fermentation, Polysaccharide-Lytic Enzymes

Received: April 2, 2025; Revised: June 27, 2025; Accepted: July 14, 2025; Published: October 31, 2025  Show citation