{"id":145488,"date":"2026-07-01T08:56:26","date_gmt":"2026-07-01T00:56:26","guid":{"rendered":"https:\/\/www.curtin.edu.au\/research\/?post_type=hdr-r-projects&#038;p=145488"},"modified":"2026-07-01T08:56:26","modified_gmt":"2026-07-01T00:56:26","slug":"optimising-dual-stage-fermentation-to-eliminate-microalgal-indigestibility-and-anti-nutritional-factors-in-commercial-herbivore-fish-feeds","status":"publish","type":"hdr-r-projects","link":"https:\/\/www.curtin.edu.au\/research\/hdr-r-projects\/optimising-dual-stage-fermentation-to-eliminate-microalgal-indigestibility-and-anti-nutritional-factors-in-commercial-herbivore-fish-feeds\/","title":{"rendered":"Optimising Dual-Stage Fermentation to Eliminate Microalgal Indigestibility and Anti-Nutritional Factors in Commercial Herbivore Fish Feeds"},"content":{"rendered":"\n<figure class=\"wp-block-image size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"792\" height=\"420\" src=\"https:\/\/www.curtin.edu.au\/research\/wp-content\/uploads\/2021\/07\/Blue-tropical-fish.jpeg\" alt=\"Brightly coloured blue and yellow tropical fish swimming in the ocean\" class=\"wp-image-117792\" style=\"width:1200px\" srcset=\"https:\/\/www.curtin.edu.au\/research\/wp-content\/uploads\/2021\/07\/Blue-tropical-fish.jpeg 792w, https:\/\/www.curtin.edu.au\/research\/wp-content\/uploads\/2021\/07\/Blue-tropical-fish-768x407.jpeg 768w\" sizes=\"auto, (max-width: 792px) 100vw, 792px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Global aquaculture urgently requires scalable and sustainable alternatives to conventional feed ingredients, including price-volatile terrestrial crops such as soybean meal and increasingly constrained marine resources such as fishmeal. Microalgae offer a nutrient-dense, climate-resilient alternative rich in essential proteins and lipids. However, their industrial application in herbivorous aquafeeds is severely constrained by two major biological constraints: severe cellular indigestibility due to a rigid, multi-layered algaenan-cellulose cell wall, and high concentrations of chemical Anti-Nutritional Factors (ANFs) such as phytic acid and tannins. When unprocessed microalgae are fed to herbivorous fish, these barriers trigger nutritional encapsulation and severe intestinal enteritis, driving up Feed Conversion Ratios (FCR). Traditional high-pressure mechanical deconstruction methods are too energy-intensive to scale profitably.<br>This project will address this bottleneck by developing a low-energy, high-throughput bioprocessing pipeline. By combining targeted enzymatic pre-treatment with automated, dual-stage microbial fermentation (Bacillus subtilis and filamentous fungi), this initiative systematically dismantles the microalgal cell wall matrix and degrades chemical ANFs. The final output is an ultra-digestible bio-meal optimised specifically for the digestive physiology of commercially farmed herbivorous fish.<\/p>\n\n\n\n<p class=\"has-intro-font-size wp-block-paragraph\">Aim&nbsp;&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Specifically, the project will investigate the effectiveness of enzymatic pre-treatment combined with bacterial and fungal fermentation in disrupting recalcitrant microalgal cell walls, reducing anti-nutritional factors, and enhancing nutrient bioavailability and digestibility. The project will generate scientific and engineering knowledge required to support the sustainable incorporation of microalgae into commercial aquaculture feed formulations.<\/p>\n\n\n\n<p class=\"has-intro-font-size wp-block-paragraph\">Objectives&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Objective 1:<\/strong> Develop and optimise an integrated enzymatic and dual-stage fermentation process using Bacillus subtilis and selected filamentous fungi to reduce microalgal cell wall recalcitrance and anti-nutritional factors.<\/li>\n\n\n\n<li><strong>Objective 2:<\/strong> Quantify changes in the physicochemical properties of microalgal biomass during processing, including cell wall disruption, nutrient accessibility, and the degradation of key anti-nutritional compounds such as phytic acid and tannins.<\/li>\n\n\n\n<li><strong>Objective 3: <\/strong>Characterise the structural and biochemical modifications of fermented microalgae using advanced analytical techniques, including microscopy (SEM\/TEM), spectroscopy, and compositional analyses.<\/li>\n\n\n\n<li><strong>Objective 4: <\/strong>Evaluate the effects of bioprocessed microalgal biomass on feed quality, nutrient digestibility, and growth performance in commercially important herbivorous fish species through feeding trials.<\/li>\n\n\n\n<li><strong>Objective 5:<\/strong> Assess the scalability, economic feasibility, and environmental sustainability of the proposed bioprocess through pilot-scale validation, techno-economic analysis (TEA), and life cycle assessment (LCA).<\/li>\n<\/ul>\n\n\n\n<p class=\"has-intro-font-size wp-block-paragraph\">Significance&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This project addresses a major challenge facing the global aquaculture industry: the sustainable replacement of conventional feed ingredients, such as soybean meal and fishmeal, with nutrient-rich microalgal biomass. Despite their nutritional potential, the widespread adoption of microalgae in aquafeeds is limited by poor digestibility and the presence of anti-nutritional factors. By developing an optimised dual-stage fermentation process, this research aims to enhance nutrient bioavailability and improve the suitability of microalgae as a commercial feed ingredient for herbivorous fish. The project also has the potential to reduce reliance on conventional feed resources while improving feed efficiency and resource utilisation.<br>From an environmental perspective, improved nutrient digestibility may reduce nitrogen and phosphorus losses to aquatic systems, thereby mitigating the environmental impacts of intensive aquaculture. The project aligns with global sustainability goals, circular bioeconomy principles, and the development of climate-resilient food production systems.<\/p>\n\n\n\n<p class=\"has-intro-font-size wp-block-paragraph\">Ideal Candidate&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">We are seeking a highly motivated PhD candidate with a background in Aquaculture, Biotechnology, Microbiology, Bioprocess Engineering, Animal Nutrition, Food Science, or a related discipline. The successful applicant should have strong analytical and problem-solving skills, with an interest in microbial fermentation, sustainable feed development, and biomass valorisation. Experience in laboratory-based research, microbial cultivation, fermentation processes, biochemical analysis, or aquaculture nutrition is desirable but not essential. Excellent written and verbal communication skills, the ability to work independently and as part of a multidisciplinary team, and eligibility for enrolment in a PhD program at Curtin University are required.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This project is open to International and Domestic applicants.&nbsp;<\/p>\n\n\n\n<p class=\"has-intro-font-size wp-block-paragraph\">Scholarship&nbsp;&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If you are identified as the preferred candidate for this project, you may be considered for an&nbsp;<a href=\"https:\/\/www.curtin.edu.au\/study\/scholarships\/research-training-program-rtp-scholarships\/\" target=\"_blank\" rel=\"noreferrer noopener\">RTP scholarship<\/a>.&nbsp;<\/p>\n\n\n\n<p class=\"has-intro-font-size wp-block-paragraph\">Enquires and How to Apply&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For enquires about this opportunity contact Dr Sufia Hena at\u00a0<a href=\"mailto:Sufia.Hena@curtin.edu.au\">Sufia.Hena@curtin.edu.au<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To formally apply submit an\u00a0<a href=\"https:\/\/forms.curtin.edu.au\/Produce\/Form\/External%20Forms\/Graduate%20Research\/\" target=\"_blank\" rel=\"noreferrer noopener\">Expression of Interest<\/a>\u00a0to Dr Sufia Hena during the Central Scholarship round (July 1st &#8211; July 31st 2026)\u00a0<\/p>\n","protected":false},"author":125,"featured_media":0,"template":"","faculties":[51],"hdr_types":[5487],"research_areas":[],"class_list":["post-145488","hdr-r-projects","type-hdr-r-projects","status-publish","hentry","faculties-science-and-engineering","hdr_types-rtp-scholarship"],"acf":false,"featured_image":false,"_links":{"self":[{"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/hdr-r-projects\/145488","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/hdr-r-projects"}],"about":[{"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/types\/hdr-r-projects"}],"author":[{"embeddable":true,"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/users\/125"}],"version-history":[{"count":0,"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/hdr-r-projects\/145488\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/media?parent=145488"}],"wp:term":[{"taxonomy":"faculties","embeddable":true,"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/faculties?post=145488"},{"taxonomy":"hdr_types","embeddable":true,"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/hdr_types?post=145488"},{"taxonomy":"research_areas","embeddable":true,"href":"https:\/\/www.curtin.edu.au\/research\/wp-json\/wp\/v2\/research_areas?post=145488"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}