Improving Peat Soil Quality for Chili Production Using Durian Pectin Microalgae in an Immobilization Matrix

ABSTRACT Peat soils in Malaysia are characterized by low nutrient content and very high acidity, which can pose challenges to agricultural productivity. This study developed a proof‐of‐concept biofertilizer to address the low nutrient content and high acidity of Malaysian peat soils. A low‐methoxyl (LM) pectin (2.97 ± 0.86% methoxyl content) was extracted from durian rind waste to create a stable, controlled‐release matrix. The microalga Chlorella vulgaris was then encapsulated within this pectin matrix using sodium alginate to observe its impact on chili plant growth and soil quality. After 30 days, chili plants grown in peat soil treated with the biofertilizer demonstrated significantly improved growth, reaching a height of 6 cm with five leaves, which is a 100% increase compared to the 3 cm height and three leaves of untreated controls. FTIR analysis of the treated soil showed distinct peaks representing hydroxyl, aliphatic, carbonyl, and polysaccharide groups (3951, 2926, 1625, and 1047 cm −1 ), suggesting increased organic matter input and enhanced microbial activity. An improved soil chemical profile was confirmed by the higher spectral intensity in treated samples. This result underscores the success of our innovative approach, which uses durian rind pectin as a natural carrier for C. vulgaris . The findings, supported by both plant growth data and FTIR analysis, reveal a significant dual‐action benefit. Biofertilizer not only enhances plant vitality but also directly improves the fundamental organic structure of soil, thus providing an effective method for rehabilitating acidic peat soil compared to conventional approaches.