Balancing the Growth Performance and Nutritional Value of Edible Farm-Raised Sago Palm Weevil (Rhynchophorus ferregineus) Larvae by Feeding Various Plant Supplemented-Sago Palm Trunk Diets.

Herein, the effect of supplementing ground sago palm trunk (GSPT) with varying concentrations of plant-based ingredients (PIs), including rice bran (RB), soybean meal (SM), and perilla seed (PS), on the nutritional profile of sago palm weevil larvae (SPWL) was investigated. Increased PS intake induced an increase in α-linolenic acid level and a reduction in the n-6/n-3 ratio in SPWL (p < 0.05). The presence of fatty acids in SPWL was determined predominantly by the fatty acid profile in the feed. The activities of Δ5 + Δ6 desaturases and thioesterase were not different among SPWL fed different diets (p < 0.05); however, PI intake resulted in low suppression of fads2 gene expression. RB, SM, and PS at the appropriate concentrations of 17.5%, 8.8%, and 7.0% in GSPT (F3 diet), respectively, boosted both protein quantity and quality of SPWL, as indicated by higher levels of essential amino acids, particularly lysine, than the FAO protein reference. Therefore, incorporating PIs into a regular diet is a viable method for enhancing the nutritional value and sustainability of farm-raised SPWL as a potential alternative source of high-quality lipid and protein.

A Novel Strategy for the Production of Edible Insects: Effect of Dietary Perilla Seed Supplementation on Nutritional Composition, Growth Performance, Lipid Metabolism, and Δ6 Desaturase Gene Expression of Sago Palm Weevil (Rhynchophorus ferrugineus) Larvae.

The nutritional value, growth performance, and lipid metabolism of sago palm weevil larvae (Rhynchophorus ferrugineus, SPWL) raised on plant-based diets (soybean, rice bran, and ground sago palm trunk (GSPT)), supplemented with various concentrations (0, 3, 7, 15, and 20%) of perilla seed (PS) were compared with traditional diets i.e., regular GSPT (control) and GSPT supplemented with pig feed. All supplemented diets rendered SPWL with higher lipid and protein contents (p < 0.05). Supplementing with 7−20% PS enhanced α-linoleic acid content in SPWL, resulting in a decrease in the n-6:n-3 ratio to a desirable level. Dietary PS supplementation increased Δ9 (18), total Δ9 and Δ5 + Δ6 desaturase indexes, fatty acid (FA) unsaturation, and the polyunsaturated FA:saturated FA ratio in SPWL, while lowering atherogenicity index, thrombogenicity index, and Δ6 desaturase (fads2) gene expression. Boosting with 7% PS improved the majority of growth parameters and enhanced essential amino acid and mineral contents (p < 0.05).

Improved long-chain omega-3 polyunsaturated fatty acids in sago palm weevil (Rhynchophorus ferrugineus) larvae by dietary fish oil supplementation.

The nutritional values of sago palm weevil larvae (SPWL) reared on mixed plant-based diets (ground sago palm trunk (GS), cornmeal, rice bran, soybean, and perilla seed), containing different levels of dietary fish oil (FO) were compared to those reared on commercial pig feed (PF) and GS. Increased FO content resulted in an increase in ω-3 fatty acids (FA) in SPWL (p < 0.05), especially α-linolenic acid and eicosapentaenoic acid. When fed FO-fortified diets instead of PF, the health-promoting indices of the SPWL lipid improved significantly (e.g., decreased ω-6/ω-3 ratio, thrombogenicity index, and hypercholesterolemic FA with increased PUFA content). The lipid, protein, and mineral contents of SPWL were increased while growth performance was maintained on a 1.5% FO-fortified diet. Higher FO levels (3-5%) had a negative impact on the nutritional values and growth performance of the SPWL. Thus, there was a reasonable chance of developing a high-nutrient alternative insect for human consumption.

Insights into the effects of dietary supplements on the nutritional composition and growth performance of sago palm weevil (Rhynchophorus ferrugineus) larvae.

Nutritional composition and growth performance of sago palm weevil larvae (SPWL) fed with ground sago palm trunk mixed with different supplements including commercial pig feed, rice bran, cornmeal, soybean meal, and perilla seed were evaluated. SPWL fed with supplemented diets were richer in protein, lipid, and mineral contents (p < 0.05). Marked increases in polyunsaturated fatty acids (10.75-fold) and omega-3 fatty acids (25.42-fold) with the lowest n-6:n-3 ratio, atherogenicity index, and thrombogenicity index were found in SPWL fed with perilla seed (p < 0.05). Perilla seed, cornmeal, and soybean meal improved essential amino acid content and essential amino acid index of SPWL. Growth performance varied, depending on feed compositions, where a comparable or even greater effect was observed in SPWL fed with supplemented diets compared to control. Therefore, plant-based supplements, especially perilla seed, efficiently improved nutritional quality of SPWL, making them more attractive in terms of nutritional and economical value.