Conference Paper
Fatty Acid Profile and Performance of Black Soldier Fly (Hermetia illucens) Larvae Fed Raw and Pre-treated Seaweeds
  • November 2025
  • Conference: Proceedings of Peradeniya University International Research Symposium and Exposition 2025
Research Interest Score
0.5
Citations
0
Recommendations
0
Reads
5
Conference Paper
Fatty Acid Profile and Performance of Black Soldier Fly (Hermetia illucens) Larvae Fed Raw and Pre-treated Seaweeds
Ruvini, increase the visibility of this article
If your co-authors confirm their authorship, more researchers will find and read this article on ResearchGate.
Abstract
Black soldier fly larvae (BSFL; Hermetia illucens) is a sustainable feed source, but their low omega-3 content limits nutritional value. However, this can be improved by rearing them on omega-3-rich substrates such as seaweed. This study evaluated BSFL’s performance and ability to bioaccumulate omega-3 from three seaweed species: Kappaphycus alvarezii, Gracilaria salicornia, and Sargassum wightii. It also examined the dietary effect of different pre-treatments of K. alvarezii on larval omeg-3 enrichment and performance. Two feeding experiments were conducted. In Experiment I, 5-day-old BSFL were reared for 14 days on eight substrates: 100% poultry manure (control), four with 12% of either fish offal or a single seaweed species, and three combining 6% fish offal with 6% seaweed. In Experiment II, 6-day-old BSFL were fed for 14 days on eight substrates: one with 100% poultry manure, one with 67% untreated K. alvarezii, and six with 67% K. alvarezii subjected to pre-treatments (enzyme: Allzyme® at 1.5% or 2%; fermentation: Saccharomyces cerevisiae at 10% or 15%; microwave: 800 W for 2 or 3 min). Experiment I showed that fish offal, whether used alone or in combination with seaweeds, enhanced the omega-3 fatty acid content in BSFL (p < 0.05). Fish offal also improved performance metrics, including feed conversion efficiency, waste reduction, and larval weight gain (p < 0.05). Among the tested seaweeds, only K. alvarezii increased omega-3 levels when used alone, though this came at the cost of reduced larval performance (p < 0.05). Experiment II demonstrated that pre-treatment of K. alvarezii e​n​h​a​n​
… 
Content uploaded by Shamila Sewwandi Subhasinghe
Author content
Content may be subject to copyright.
Page 1
S esVERSIतल्यOF PERADENIVA பேராதயைलोचनPURSE 2025PERADENIYA UNIVERSITYINTERNATIONAL RESEARCH SYMPOSIUMAND EXPOSITIONNavigating the Future:A Multidisciplinary Perspective+PROCEEDINGSVolume 26https://doi.org/10.63967/AULT4918th th28 and 29 August 2025
Page 2
Proceedings of Peradeniya University International Research Symposium and Exposition 2025, Sri Lanka, Vol. 26, 28-29 Aug. 2025250Fatty Acid Profile and Performance of Black Soldier Fly (Hermetia illucens) LarvaeFed Raw and Pre-treated SeaweedsH.W.S.S. Subhasinghe1, W.A.D.E.I. Wijesingha1, B.C. Jayawardana1, R. Liyanage2,P. Weththasinghe1*1Department of Animal Science, Faculty of Agriculture, University of Peradeniya,Peradeniya, 20400, Sri Lanka2Laboratory of Nutrition and Biochemistry, National Institute of Fundamental Studies,Kandy, 20000, Sri Lanka*pabodhaw@agri.pdn.ac.lkBlack soldier fly larvae (BSFL; Hermetia illucens) is a sustainable feed source, but theirlow omega-3 content limits nutritional value. However, this can be improved by rearingthem on omega-3-rich substrates such as seaweed. This study evaluated BSFL’sperformance and ability to bioaccumulate omega-3 from three seaweed species:Kappaphycus alvarezii, Gracilaria salicornia, and Sargassum wightii. It also examinedthe dietary effect of different pre-treatments of K. alvarezii on larval omeg-3 enrichmentand performance. Two feeding experiments were conducted. In Experiment I, 5-day-oldBSFL were reared for 14 days on eight substrates: 100% poultry manure (control), fourwith 12% of either fish offal or a single seaweed species, and three combining 6% fishoffal with 6% seaweed. In Experiment II, 6-day-old BSFL were fed for 14 days on eightsubstrates: one with 100% poultry manure, one with 67% untreated K. alvarezii, and sixwith 67% K. alvarezii subjected to pre-treatments (enzyme: Allzyme® at 1.5% or 2%;fermentation: Saccharomyces cerevisiae at 10% or 15%; microwave: 800 W for 2 or 3min). Experiment I showed that fish offal, whether used alone or in combination withseaweeds, enhanced the omega-3 fatty acid content in BSFL (p < 0.05). Fish offal alsoimproved performance metrics, including feed conversion efficiency, waste reduction,and larval weight gain (p < 0.05). Among the tested seaweeds, only K. alvareziiincreased omega-3 levels when used alone, though this came at the cost of reducedlarval performance (p < 0.05). Experiment II demonstrated that pre-treatment of K.alvarezii enhanced larval omega-3 content, compared to untreated seaweed (p < 0.05).While both untreated and pre-treated K. alvarezii generally reduced larval performance(p < 0.05), substrates containing pre-treated seaweed showed numerical improvementsin growth and efficiency metrics compared to untreated seaweed. These findingshighlight the potential of pre-treated seaweed substrates to enrich BSFL with omega-3fatty acids, offering a promising strategy to improve the nutritional value of insect-basedfeeds.Keywords: Insect, black soldier fly larvae, seaweed, pre-treatment, omega-3Acknowledgement: This study was funded by the University Research Grant Year 2022,University of Peradeniya, Sri Lanka (Grant No: URG/2022/03/Ag).
Similar research
Fatty Acid Profile and Growth Performance of Black Soldier Fly Larvae (Hermetia illucens) Grown on Pre-Treated Seaweed
Conference Paper
Full-text available
Despite being a promising feed source for animals, black soldier fly larvae (Hermetia illucens; BSFL) are poor in omega-3 contents. Omega-3 rich substrates can be used to improve the omega-3 content in BSFL, but such substrates also cause poor larval performance. Therefore, this study evaluated the effect of feeding pre-treated seaweed (Kappaphycus alvarezii) on fatty acid profile and performance of BSFL. Eight substrates were prepared using poultry manure as the basal ingredient: a substrate containing 100% poultry manure; a substrate containing 67% untreated seaweed and six substrates containing 67% pre-treated seaweed in six different methods including Allzyme® treated at 1.5% (w/w) and 2% (w/w), fermented with 10% (v/v) and 15% (v/v) Saccharomyces cerevisiae, microwaved at 800 W for 2 and 3 minutes. A total of 6 days-old 9600 BSFL were randomly distributed into 24 plastic containers (400 larvae per container) and fed with one of the eight substrates for 14 days (n=3). At the beginning and end of the experiment, weights of larvae were recorded. Proximate and fatty acid compositions of substrates and BSFL were measured. Inclusion of both untreated and pre-treated seaweed in substrates enriched omega-3 in BSFL. The highest (p<0.05) EPA and DHA contents were observed in BSFL fed seaweed microwaved for 2 minutes and untreated seaweed, respectively. Pre-treated seaweed except enzyme-treated seaweed at 2%, increased (p<0.05) EPA contents in BSFL than untreated treatment. The BSFL fed seaweed showed lower (p<0.05) body weight gain, bioconversion efficiency, nitrogen conversion efficiency than those fed 100% poultry manure. However, in comparison with pretreated seaweed, enzyme-treated seaweed at 2% caused higher (p<0.05) body weight gain compare to the microwave 3 minutes while other performance were same. In conclusion, pre-treatment of K. alvarezii with enzymes, fermentation and microwave can increase the capacity of seaweeds to increase EPA content in BSFL without compromising the performance. Keywords: Black soldier fly larvae, Larval performance, Omega-3 enrichment, Pre treatment, Seaweed
Effect of Enzymatic, Fermentation, and Microwave Pre-treatments on Nutrient Composition of Seaweed (Kappaphycus alvarezii)
New
Conference Paper
Full-text available
Seaweed is a sustainable, nutrient-rich source of proteins, carbohydrates, essential fatty acids, and micronutrients. However, its rigid, polysaccharide-rich cell walls limit nutrient bioavailability. Pre-treatment methods can disrupt these cellular structures, enhance nutrient accessibility and support seaweed’s potential as a nutritious ingredient in both animal feed and human food. This study evaluated the effects of different pre treatment techniques, such as enzymatic hydrolysis, yeast fermentation and microwave heating on the proximate composition of Kappaphycus alvarezii. Seaweed samples collected from Jaffna, Sri Lanka were dried, powdered and subjected to one of the six treatments: enzymatic treatment with Allzyme® at 1.5% or 2% (w/w), fermentation with Saccharomyces cerevisiae at 10% or 15% (v/v), or microwave heating at 800 W for 2 or 3 min. Allzyme® contained protease, phytase, cellulose, beta glucanase, amylase and xylanase enzymes. An untreated, sample served as the control. Proximate composition: moisture, crude protein, crude fat, crude fiber, ash, and nitrogen-free extract (NFE), was assessed using AOAC methods. Pre-treatments significantly (p < 0.05) affected seaweed’s nutrient profile. Enzyme treatment (1.5%) increased crude protein content of seaweed from 5.9% to 9.4%, while 10% fermentation yielded the highest protein content (10.0%). Fermentation at 10% and 15% notably reduced fat content (1.0% and 1.8%, respectively), whereas microwave treatment for 2 min produced the highest fat content (3.0%). Crude fiber content decreased with 10% fermentation (7.5%) and 1.5% enzymatic treatment (7.7%) compared to the control (9.8%). The highest NFE value (67.1%) was observed in the 2% enzyme-treated group, indicating enhanced carbohydrate content. Ash content remained relatively unchanged (16.7–17.8%) among the pre-treatment methods. These results demonstrate that enzymatic, microwave, and fermentation pre-treatments enhance the nutritional value and potential bioavailability of seaweed, supporting its use as a functional ingredient in food and feed formulations.
Download
Bioavailability of Antioxidants, Minerals and Heavy Metals in Two Edible Seaweed Species: Kappaphycus alvarezii and Caulerpa racemose
New
Conference Paper
Full-text available
Sri Lanka is endowed with an abundance of marine resources, yet numerous seaweed species remain underutilized and accumulate as waste along coastal beaches. This represents a missed opportunity to transform marine biomass into valuable resources. The present study was undertaken to evaluate the bioavailability of antioxidants, minerals, and heavy metals in two edible, Sri Lankan seaweeds: Kappaphycus alvarezii and Caulerpa racemose. Seaweed drying at 55 °C and powdered and subjected to the in vitro gastrointestinal digestion, simulating enzymatic breakdown and intestinal absorption using a 12 kDa dialysis membrane. Polyphenol contents were quantified before and after digestion by Folin-Ciocalteu and aluminium chloride colorimetric methods, while antioxidant capacities were evaluated through 2,2-Diphenyl-1-picryl-hyrazyl-hydrate radical scavenging (DPPH) activity, 2,2′ azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging (ABTS) activity and ferric reducing antioxidant power assays (FRAP). Essential minerals (Fe, K, Mg, Al, Zn) and potential heavy metals were analyzed using Inductively Coupled Plasma-Optical Emission spectroscopy. Results revealed significantly higher total phenolic content in bioavailable fractions compared to raw seaweed for both species, while total flavonoid content was undetectable. Notably, bioavailable fractions enhanced antioxidant activity in the ABTS assay, but reduced activity in DPPH radical scavenging compared to raw fractions. C. racemosa showed greater FRAP values in the bioavailable fraction. The bio-accessible mineral and heavy metal contents were markedly higher in K. alvarezii. These findings demonstrate that digestion increases the release and accessibility of polyphenols and minerals in seaweeds, supporting marine biomass recycling as functional ingredients to address micronutrient deficiencies and oxidative stress-related diseases while promote sustainable resource utilization and reducing coastal waste. Keywords: Antioxidants, Bioavailability, Heavy Metals, In Vitro Digestion, Seaweed Acknowledgement, The authors sincerely thank Mr. Nirooparaj Balachandran, Assistant Director (Coastal–Northern Province) at the National Aquaculture Development Authority, Sri Lanka, for his valuable assistance in the collection of seaweed samples.
Antioxidant and antimicrobial activity of drumstick (Moringa oleifera) leaves in herbal chicken sausages
Article
Private full-text
LWT
Does Processing have a Considerable Effect on the Nutritional and Functional Properties of Mung Bean (Vigna Radiata)?
Article
Full-text available
Procedia Food Science
Mung bean is an important grain legume which is rich in nutrients and other bioactive compounds with many beneficial physiological effects. However, the effect of processing on properties of mung bean has not been widely studied in Sri Lanka. In the current study, effect of processing (boiling and sprouting) on some nutritional and functional properties of mung bean was investigated in comparison with raw mung bean. Mung bean seeds (Vigna radiata), varity MI6 were obtained from the Government Seed Center, Dambulla, Sri Lanka. Proximate composition, gross energy, insoluble dietary fibre (IDF) and soluble dietary fibre (SDF) contents,total phenolic content (TPC), total flavonoid content (TFC), α-amylase inhibition capacity, DPPH and ABTS scavenging activities were determined. Crude Protein (CP) content of boiled mung bean was significantly (p<0.05) lower than that of raw mung bean while it was significantly (p<0.05) higher in sprouted mung bean than raw mung bean. Crude fat content (CF) was significantly (p< 0.05) lower in sprouted mung bean when compared to raw mung bean. IDF contents in raw mung bean was significantly (p<0.05) higher than that in sprouted and boiled mung bean whereas, SDF content in boiled and sprouted mung bean were significantly (p<0.05) higher than that in raw mung bean.processing significantly (p<0.05) reduced antioxidant activity and total phenol content compared to raw mung bean. However, flavonoids could only be detected in sprouted mung bean. Further, α-amylase inhibition in sprouted mung bean was significantly (p<0.05) higher than that in boiled mung bean. In conclusion, processing (boiling and sprouting) influences the CP content, CF content, dietary fibre content, antioxidant capacity, α-amylase inhibition and fermentation ability in mung bean.