Sains Malaysiana 55(6)(2026): 1088-1099

http://doi.org/10.17576/jsm-2026-5506-13

 

Municipal Sludge–Derived Biochar Enriched with Pseudomonas sp. Isolate RA-21 Enhances Soil Properties and Capsicum annuum Growth

(Bioarang Terbitan Enapcemar Perbandaran Diperkaya dengan Pseudomonas sp. Pencilan RA-21 Meningkatkan Sifat Tanah dan Pertumbuhan Capsicum annuum)

 

MUHAMMAD AZHAM ABDULLAH¹, AHMAD RAZI OTHMAN^1,2,*, NUR NADHIRAH RAMLI¹ & RUSLI DAIK³

 

¹Department of Chemical and Process Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

²Research Centre for Sustainable Process Technology (CESPRO), Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

³Department of Chemical Science, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

 

Diserahkan: 13 Mac 2025/Diterima: 12 Jun 2026

 

Abstract

The growing world population has increased the demand for food to meet global needs, which contributed to the growth and vibrancy of the agricultural sector. There is an urgent need for soil treatment to restore healthy soil conditions due to extensive and unregulated agricultural activities that have degraded soil fertility, resulting in reduced crop yields. Sludge from a municipal wastewater treatment plant is potentially used in biochar production. Thus, the combination of biochar with plant growth-promoting bacteria offers an ecologically friendly alternative for improving soil health and agricultural output. ICP-MS and Brunauer–Emmett–Teller (BET) analysis were used to determine the quality of the developed biochar. An indigenous Pseudomonas sp. isolate, RA21, was mixed with biochar and used as a soil conditioner to promote chili plant growth. Plant height, leaf size, and stem diameter were measured to compare treated and untreated plants. ICP-MS analysis indicates that zinc and iron were the dominant metals present in all samples. BET analysis shows that approximately 70% of the biochar pore volume is composed of mesopores. The Fe and Zn nutrients in biochar serve as nutrient sources for plant uptake, while the high proportion of mesopores provides sites for bacterial colonization and enhances adsorption capacity. The application of a soil conditioner resulted in greater plant growth variables such as height, leaf size, and stem diameter when compared to the control group, and was equivalent to commercial fertiliser. Using soil conditioner resulted in more leaf area (651 cm²) in chilli plants compared to those treated with commercial fertiliser (629 cm²). Biochar, in particular, serves as a transporter for bacteria, allowing for optimal growth and activity while also providing nutrients that promote healthy plant development. The combination of sludge-derived biochar with the indigenous Pseudomonas sp. strain RA21 has shown encouraging results as a soil conditioner by increasing nutrient availability, allowing for the value-added use of municipal sludge within a circular economy framework.

Keywords: Biochar; Pseudomonas sp.; sludge-derived biochar; soil conditioner

 

Abstrak

Populasi dunia yang semakin meningkat telah meningkatkan permintaan terhadap makanan untuk memenuhi keperluan global, yang mana menyumbang kepada pertumbuhan dan merancakkan sektor pertanian. Terdapat keperluan mendesak untuk merawat tanah bagi memulihkan semula keadaan tanah yang sihat akibat daripada aktiviti pertanian yang meluas dan tidak terkawal yang telah merosotkan kesuburan tanah, sekali gus mengurangkan hasil tanaman. Sisa pepejal dari loji rawatan air sisa bandar berpotensi digunakan dalam penghasilan bioarang. Oleh itu, gabungan bioarang dengan bakteria penggalak pertumbuhan tumbuhan menawarkan alternatif yang mesra alam untuk meningkatkan kesihatan tanah dan hasil pertanian. Analisis ICP-MS dan Brunauer–Emmet–Teller (BET) digunakan untuk menentukan kualiti bioarang yang dihasilkan. Bakteria Pseudomonas sp. pencilan RA21 dicampurkan dengan bioarang dan digunakan sebagai perapi tanah untuk merangsang pertumbuhan tanaman cili. Ketinggian pokok, saiz daun dan diameter batang diukur untuk membandingkan tanaman yang dirawat dan tidak dirawat. Analisis ICP-MS menunjukkan zink dan ferum merupakan logam berat utama yang terdapat dalam semua sampel. Analisis BET menunjukkan kira-kira 70% liang bioarang terdiri daripada liang mikro. Nutrien Fe dan Zn dalam bioarang berfungsi sebagai sumber nutrien untuk penyerapan tumbuhan, manakala peratusan mesoliang yang tinggi menyediakan tapak bagi pengkolonian bakteria serta meningkatkan kapasiti penjerapan. Penggunaan perapi tanah menghasilkan keluasan daun yang lebih besar (651 cm²) pada tanaman cili berbanding tanaman yang dirawat dengan baja komersial (629 cm²). Bioarang khususnya bertindak sebagai pengangkut bagi bakteria, membolehkan pertumbuhan dan aktiviti yang optimum di samping membekalkan nutrien yang menyokong perkembangan tumbuhan yang sihat. Gabungan bioarang terhasil daripada enap cemar dengan strain Pseudomonas sp. pencilan RA21 menunjukkan hasil yang memberangsangkan sebagai bahan pembaik tanah melalui peningkatan ketersediaan nutrien, sekali gus membolehkan penggunaan nilai tambah enap cemar perbandaran dalam kerangka ekonomi kitaran.

Kata kunci: Bioarang; bioarang berasaskan enap cemar; perapi tanah; Pseudomonas sp.

 

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*Pengarang untuk surat-menyurat; email: ahmadrazi@ukm.edu.my