Sains Malaysiana 55(5)(2026): 812-824

http://doi.org/10.17576/jsm-2026-5505-04

 

Salicylic Acid-Induced Astaxanthin Accumulation in Mixed Culture of Nannochloropsis oculata and Arthrospira platensis Cultivated in Tofu Wastewater

(Pengumpulan Astaxantin Teraruh Asid Salisilik dalam Kultur Campuran Nannochloropsis oculata dan Arthrospira platensis yang Dikultur dalam Air Sisa Tauhu)

 

TAUFIK TAUFIKURAHMAN1,*, RUTH YOHANNA BANJARNAHOR1, LILI MELANI1, SITI ROZAIMAH SHEIKH ABDULLAH2, ERI SAHABUDIN3, DIAN NOVERITA WIDYANINGRUM3 & HANI SUSANTI3

 

1School of Life Sciences and Technology, Bandung Institute of Technology, Jl. Ganesha 10 Bandung 40132, Indonesia

2Research Centre for Sustainable Process Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

 3Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN), The Soekarno Science & Technology Park, Cibinong 16911, Indonesia

 

Diserahkan: 11 Februari 2026/Diterima: 6 Mei 2026

 

Abstract

Astaxanthin is a significant ketocarotenoid with health benefits, and its use is widely celebrated in nutraceuticals, cosmetics, and aquaculture. Increasing customer demand is driven by concerns over synthetic alternatives and naturally occurring astaxanthins have been greatly marketed, prompting attempts to improve their biological production. In addition to the literature that has been previously explored, we developed a culture of the Nannochloropsis oculata and Arthrospira platensis (Spirulina) under open raceway pond (55 L working volume). We used tofu wastewater as growth medium and evaluated salicylic acid (SA) reaction effect as the elicitor. Three concentrations of SA (0, 20, and 200 µM) were tested. Growth rate (0.66 d⁻¹), biomass yield (1.33 g L⁻¹), biomass productivity (0.14 g L⁻¹ d⁻¹), and chlorophyll-a content (7.03 mg L⁻¹) was highest after adding 20 µM of SA. This treatment also obtained the highest astaxanthin content (0.11 mg g⁻¹ dry biomass), with a 1.88-fold increase over the control. A higher SA concentration (200 µM) did not further improve biomass or astaxanthin accumulation. The results indicate that moderate SA will increase astaxanthin production in mixed microalgal cultures. Moreover, the application of tofu wastewater forms a sustainable mode of biowaste valorization and is cost-effective to carry out large-scale cultivation. Overall, this strategy is a prospective approach for developing natural astaxanthin under open cultivation.

Keywords: Mixed culture; open raceway pond; salicylic acid; Spirulina; tofu wastewater

 

Abstrak

Astaxantin adalah ketokarotenoid yang penting dengan manfaat kesihatan dan penggunaannya diraikan secara meluas dalam nutraseutikal, kosmetik dan akuakultur. Permintaan pelanggan yang semakin meningkat didorong oleh kebimbangan terhadap sintetik alternatif dan astaxantin yang berlaku secara semula jadi telah dipasarkan dengan meluas, mendorong usaha untuk meningkatkan pengeluaran biologi mereka. Selain daripada kepustakaan yang telah diterokai sebelum ini, kami telah membangunkan kultur Nannochloropsis oculata dan Arthrospira platensis (Spirulina) di bawah kolam palung terbuka (55 L isi padu kerja). Kami menggunakan air sisa tauhu sebagai medium pertumbuhan dan menilai kesan reaksi asid salisilik (SA) sebagai pengelisit. Tiga kepekatan SA (0, 20 dan 200 µM) telah diuji. Kadar pertumbuhan (0.66 d⁻¹), hasil biojisim (1.33 g L⁻¹), produktiviti biojisim (0.14 g L⁻¹ d⁻¹) dan kandungan klorofil-a (7.03 mg L⁻¹) adalah tertinggi selepas menambah 20 µM SA. Rawatan ini juga memperoleh kandungan astaxantin tertinggi (0.11 mg g⁻¹ biojisim kering) dengan peningkatan 1.88 kali ganda berbanding kawalan. Kepekatan SA yang lebih tinggi (200 µM) tidak meningkatkan lagi pengumpulan biojisim atau astaxantin.  Keputusan menunjukkan bahawa SA sederhana akan meningkatkan pengeluaran astaxantin dalam kultur mikroalga campuran. Selain itu, penggunaan air sisa tauhu membentuk satu cara lestari untuk memanfaatkan sisa bio dan adalah kos efektif untuk menjalankan penanaman berskala besar.  Secara keseluruhan, strategi ini adalah pendekatan yang berpotensi untuk membangunkan astaxantin semula jadi di bawah penanaman terbuka.

Kata kunci: Air sisa tauhu; asid salisilik; kultur campuran; kolam palung terbuka; Spirulina

 

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*Pengarang untuk surat-menyurat; email: taufik@itb.ac.id

 

 

 

 

 

 

 

           

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