Soldier Fly Research Articles

The impact of early-life conditions on visual discrimination abilities in free-ranging laying hens

Conditions during incubation and rearing can greatly affect the developmental trajectory of chickens, in a positive and negative way. In this study, the effect of early-life conditions on the visual discrimination abilities of adult, free-ranging laying hens was examined. These early-life treatments entailed incubation in a 12/12h green light/dark cycle and rearing with Black soldier fly larvae (BSFL) as foraging enrichment. Through a modified pebble-floor test, 171 hens of 41 to 42 wk old, housed in mobile stables with outdoor access, were tested for their ability to discriminate between food and nonfood items (mealworms and decoy mealworms). Each hen was allowed 60 pecks during the trial, from which the overall success rate, as well as within-trial learning was investigated. The latter was accomplished by dividing the 60 pecks into 3 blocks of 20 pecks and comparing the success rate between these blocks. Due to another ongoing experiment on range use, roughly half the hens received range enrichment (mealworms) at the time of testing, so this was included as a covariate in the analysis. Incubation with green light did not have an effect on the visual discrimination abilities of adult laying hens. Rearing with BSFL did have a limited beneficial effect on the visual discrimination abilities, as evidenced by a higher success rate during the first block of the visual discrimination trial. These enhanced visual discrimination abilities might be useful in a more complex free-range setting, where the animals have more foraging opportunities. Hens that received range enrichment at the time of testing, also had a higher success rate during the visual discrimination test, though they had a lower degree of test completion, likely due to habituation to the mealworms as an enrichment. The positive effects of BSFL during rearing and mealworms during the laying period stress the importance of enrichment throughout the life of the hens.

Sosialisasi Pengolahan Sampah Organik Rumah Tangga dengan Maggot BSF di Desa Gelam Kabupaten Sidoarjo

The village of Gelam village in Sidoarjo is one of the areas facing a significant problem with the accumulation of organic waste. To address this issue, this community is processing organic waste using Black Soldier Fly (BSF) maggots. The training methods include location surveys, socialization, and direct education to the community about organic waste processing using BSF maggots. The results of this activity show that the community has understood the method of processing waste using BSF maggots and is interested in conducting small-scale maggot cultivation. This activity also helps reduce organic waste accumulation and creates new job opportunities. Therefore, it is the standard of the community in Gelam village.

A Comprehensive Analysis of Chitin Extraction from the Black Soldier Fly for Chitosan Production

A Comprehensive Analysis of Chitin Extraction from the Black Soldier Fly for Chitosan Production

Suitability of Different Ovipositional Trap for Black Soldier Fly (Hermetia illucens)

The Black Soldier Fly (Hermetia illucens) has garnered significant attention as a sustainable and nutrient-rich option for poultry feed, due to its high protein and fat content. This study assesses the oviposition preference of female black soldier flies among different ovipositional traps like cardboard, wood, corrugated plastic tubes, and an outside area within a controlled environment. Employing a completely randomized block design, we assessed a range of parameters, including ovipositional trap selection, oviposition duration, egg count, fertility, offspring development, and mortality rate. The findings revealed that plastic tubes were the most favoured ovipositional trap, attracting 142.67 female visits, with an impressive average egg-laying duration of 13 minutes and an egg fertility rate of 85.33%. Such preference may be due to the optimal microenvironment plastic material provides for oviposition of the Soldier fly females. Cardboard traps garnered 122.67 visits, with a notable 10.67-minute egg-laying duration and a fertility rate of 72.67%. Interestingly, wood traps were the least attractive, with only 52.33 visits, the shortest egg-laying duration (6 minutes), and a fertility rate of 33.67%. These results demonstrate the significant role that material choice plays in the reproductive success of Hermetia illucens. The corrugated plastic tubes are the best ovipositional traps for the efficient mass-rearing of black soldier flies for both research and commercial requirements.

Strategic approach for converting fat-rich food waste into high-quality biodiesel using black soldier fly larvae for sustainable bioenergy

Food waste (FW) comprises carbohydrates, proteins, lipids, and water, posing technical challenges for effective treatment and valorisation. This study addresses these challenges by using black soldier fly larvae (BSFL) as a bioconversion medium to transform FW into biodiesel (BD). BSFL predominantly consumed the carbohydrates and proteins in FW (81 wt%), while showing a lower preference for lipids (<50 wt% consumed). Notwithstanding the lower consumption of lipids in the FW than that of carbohydrates and proteins, BSFL had a high lipid content (48.3 wt%). The subsequent conversion of the lipids extracted from BSFL into BD was tested via catalytic (acid/alkali) and non-catalytic transesterification processes. The BD yield from catalytic transesterification was lower than that from non-catalytic transesterification because of the low tolerance against free fatty acids (FFAs). BD was also produced from the lipid-concentrated residual FW through non-catalytic transesterification. Although the FW residue extracts contained high amounts of FFAs (49.9 wt%), non-catalytic transesterification displayed a high BD yield (92.4 wt%; yields from catalytic transesterification: < 80.0 wt%). Moreover, blending the BD derived from the BSFL and FW residue extracts enhanced the fuel properties. The BSFL-assisted FW management efficiently reduced FW by 90 wt% while producing a high-quality BD.

Current and Potential Applications of Vibrational Spectroscopy as a Tool in Black Soldier Fly Production and the Circular Economy

Edible insects are characterized by their low environmental footprint compared with traditional sources of animal and plant proteins. This is due to the high feed conversion efficiency of edible insects. The black soldier fly (Hermetia illucens) larvae (BSFL) are one of the preferred candidates to be used as alternative sources of protein, due to their ability to add value to a wide range of organic and food waste streams. The ability of BSFL to convert organic matter into protein has resulted in a viable and sustainable ingredient to be utilized in animal feed or human food. BSFL have also been considered as key components of the circular economy due to their intrinsic characteristics and properties. The evaluation of the chemical composition, nutritive value, and functional properties of BSFL have been achieved by the utilization of traditional methods of analysis, although most of these procedures do not agree with the requirements of a circular economy due to their intrinsic characteristics (e.g., destructive, energy use, highly reactive reagents, etc.). Therefore, green analytical technologies have been evaluated, of which infrared (IR) spectroscopy has several advantages. This article reviews current and potential applications of IR spectroscopy combined with chemometrics to analyze the proximate composition, functional characteristics, and traceability of BSFL and frass samples.

Performance, egg quality and organ traits of laying hens fed black soldier fly larvae products

Due to consumer demands and institutional pressure, the egg production sector, is looking for alternative protein sources for laying hen feed to support more sustainable, circular production. black soldier fly (BSF) larvae could be used as a protein source. In addition to protein the larvae contain large quantities of fat and can either be fed to laying hens unprocessed (alive) or processed (meal and oil). The current study was performed with 560 Brown Nick laying hens from 20 to 27 wk of age. The laying hens were divided over 5 treatments, each replicated 8 times. Treatments consisted of standard laying hen feed (control) and standard feed in which soybean meal was partly exchanged with live BSF larvae or BSF larvae meal and oil combined, at 2 inclusion levels. During the experiment production parameters, egg-quality, and length and weight of various organs were measured. Laying hens fed BSF larvae products consumed less feed compared to those of the control group. Most egg production parameters were similar, however laying hens fed diets with BSF larvae meal plus oil produced eggs with lower egg weight during the last 2 wk of the experiment, compared to the control group. All egg-quality characteristics remained the same across treatments, except for darker yolk colors when feeding BSF meal and oil and high inclusion of live BSF larvae. This is a favorable characteristic for European consumers. The weight of intestinal organs was largely unaffected by the treatments. The jejunum and ileum weight of laying hens fed live larvae was lower compared to the control group. As FCRs were similar or improved compared to the control group, we assume that nutrient utilization was not impaired. For most detected differences the type of BSF larvae product (live larvae or meal plus oil) rather than inclusion level was of significance.

Sustainable organic electrodes using black soldier fly-derived melanin for zinc-ion hybrid capacitors

Pressing environmental challenges require focused research on sustainable solutions in the domains of energy, water, food, land, and climate. The pigment eumelanin has recently been positioned as a promising candidate for solving issues in health, sensors, and energy storage. However, the low solubility of eumelanin in aqueous solvents, difficult film processibility, and high cost have hindered the material from wide deployment. Here, we propose melanin extracted from the black soldier fly, Hermetia illucens (Mel-BSF), as a sustainable alternative for the preparation of organic electrodes in energy storage applications. Mel-BSF displays pseudocapacitive behaviour with a high potential window, good electrochemical stability, and higher maximum capacity (91.8 mAh g−1) compared to synthetic eumelanin (17.3 mAh g−1) as the working electrode material in zinc-ion hybrid capacitors using an ionic liquid electrolyte. Structural and surface investigations reveal that additional aliphatic compounds, potentially lipids present after Mel-BSF refinement, significantly increase the film stability and redox centre availability.

Nutritional Value of the Larvae of the Black Soldier Fly (Hermetia illucens) and the House Fly (Musca domestica) as a Food Alternative for Farm Animals-A Systematic Review.

Dietary alternatives using insect-based products as an alternative for farm animal nutrition have been the object of study due to the high nutritional value of these feeds and the costs related to both their production and consequently their commercialization. Thus, the use of flies, especially larvae, has a high content of proteins and lipids (fat), as well as minerals and essential nutrients for development and growth, directly impacting the production of these animals, whether meat or milk. Therefore, the objective of this study was to compile data from the literature on the nutritional value of adults and larvae of Black soldier (Hermetia illucens) and housefly (Musca domestica) as a dietary alternative for animal feed. The Prisma checklist was used. After reviewing the data found in the literature, following the systematic review, it was noted that studies emerge that larvae of black soldier flies and domestic flies of the order Diptera obtain essential sources in the nutrition of ruminants, in addition to obtaining rapid digestibility, thus adhering to reproduction with high nutritional content, due to incident levels of protein, lipids, and minerals in M. domestica and Lucilia sericata, making it a target for inclusion in the diet of farm animals. In addition, it is concluded that both species are studied for their sustainable potential as well as for offering greater economic and nutritional viability when compared to ingredients present in production animal feed.

Economic Empowerment of Micro, Small, and Medium Enterprises (MSMEs) in the Leather Industry through Black Soldier Fly (BSF) Magot Cultivation

Economic Empowerment of Micro, Small, and Medium Enterprises (MSMEs) in the Leather Industry through Black Soldier Fly (BSF) Magot Cultivation

Suppressive Effect of Black Soldier Fly Larvae Frass on Fusarium Wilt Disease in Tomato Plants.

This study investigated the effect of black soldier fly larvae (BSFL) frass derived from BSFL reared on a diet composed of fruit/vegetable/bakery/brewery residues (FVBB diet) and on the Gainesville diet (GV diet) on the development of tomato (Solanum lycopersicum) Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (FOL). Tomato plants were grown in a substrate inoculated with FOL that was amended (10%, v:v) or not (control) with either a commercial compost, pasteurized (70 °C for 1 h) frass from BSFL reared on a FVBB diet, non-pasteurized frass from BSFL reared on a FVBB diet, pasteurized frass from BSFL reared on the GV diet, or non-pasteurized frass from BSFL reared on the GV diet. The results show that frass from BSFL reared on the GV diet, irrespective of pasteurization, inhibited FOL root colonization and reduced the severity of tomato Fusarium wilt to a far greater extent than frass from BSFL reared on a FVBB diet and commercial compost made of peat, seaweed, and shrimps. This study suggests that BSFL frass, depending on the larval rearing diet, has the potential to serve as a pasteurized or non-pasteurized soil amendment with prophylactic properties against FOL in tomato plants, opening new avenues of research for the valorization of BSFL frass.

Isolation of chitosan-melanin complex from black soldier fly adults and obtaining nanofibrous materials based on it

The article presents the results of studying the viscosity of chitosan-melanin complex solutions from the larvae of the insect Hermetia illucens and the process of gelation in these solutions in the presence of crosslinking reagents. Chemically cross-linked nanofibers were obtained from solutions of the chitosan-melanin complex in dilute solutions of acetic acid by the method of spinneretless electrospinning. The presence of 14% melanin made it possible to reduce the concentration of acetic acid in the spinning composition.

The Effect of a Combination of Coconut Dregs and Fermented Chicken Manure on Population, Weight and Length of Maggots (Hermetia illucens)

Maggot is an organism that originates from the eggs of the BSF fly (Black Soldier Fly) which is usually known as a rotting organism because of its habit of consuming organic materials. Maggots can be an alternative feed because they have a fairly high protein content and are suitable as fresh fish feed or as raw fish feed ingredients. The study aims to determine the effect of the proportion of the combination of coconut pulp and fermented chicken manure on the population, weight and length of maggot (Hermetia illucens). This research method used an experiment with 6 treatments, 5 replicates for each treatment. The treatments applied were T1: 100% coconut pulp, T2: 95% coconut pulp + 5% chicken manure, T3: 90% coconut pulp + 10% chicken manure, T4: 85% coconut pulp + 15% chicken manure, T5: 80% coconut pulp + 20% chicken manure, T6: 75% coconut pulp + 25% chicken manure. Maggot maintenance started from 0-14 days of age. The observed paramameter of the population were weight and length of maggot (Hermetia illucens). This study used a Complete Random Design (RAL) with 5 replicates and the data was analyzed using Analysis of Variance (ANOVA). Based on the results of statistical analysis, the combination of coconut pulp and fermented chicken manure on the population, weight and length of manggot (Hermetia illucens) (P &lt; 0.05). The results of the research on the combination of coconut pulp and fermented chicken manure with different combinations showed that there were some differences. T6 treatment was able to show the highest results in population, weight and length of maggot (Hermetia illucens).

Impact of Black Soldier Fly Larval Frass on Growth and Yield of Cluster Bean (Cyamopsis tetragonoloba L.)

Hermetia illucens L., commonly known as the Black Soldier Fly (BSF), has garnered global attention for its role in insect farming due to its efficient conversion of organic waste into nutrient-rich larval biomass, with frass as a primary byproduct. This study aimed to explore the potential of BSF larval frass (BSFF) as an organic fertilizer for agricultural production, especially evaluating its performance compared to vermicompost on cluster bean growth and yield under field conditions during rabi season at Rajendranagar, Hyderabad. Using a completely randomized block design with eight treatments, various growth parameters such as plant height, number of branches plant-1 and dry matter production, along with yield attributes including number of clusters plant-1, number of pods cluster-1, number of pods plant-1, pod weight (g), pod yield plant-1 and yield (t ha-1) were assessed. Significant differences were observed among treatments, the highest growth and yield parameters were recorded in application of 25 % N through BSF frass + 75 % RDN (T5) and it was on par with 25 % N through vermicompost + 75 % RDN (T6), 50 % N through BSF frass + 50 % RDN (T7), 50 % N through vermicompost + 50 % RDN (T8) and RDF (T2) compared to 100 % N through BSF frass (T3), 100 % N through vermicompost (T4) and control (T1).These treatments resulted in yield increase of 35.7 % (T5), 24.7 % (T6), 23.4 % (T7), 22 %(T8) and 24.36 % (T2) respectively, compared to the control. These findings indicated that BSF larval frass holds promise as a sustainable alternative to vermicompost for enhancing cluster bean production, offering potential benefits for agricultural sustainability and organic waste management.

Selective cytotoxicity of standardised n-hexane extract of black soldier flies’ larvae on cancerous skin cells mitochondria isolated from rat model of melanoma

Introduction Melanoma is known as a highly lethal cancer. In melanoma cells, apoptosis signalling which relies heavily on the acute activity of mitochondria and reactive oxygen species (ROS) formation is suppressed. Our previous studies on natural compounds on melanoma suggested that mitochondria are a potential target for the melanoma treatment by selective cytotoxic effect of them. The black soldier fly is an important environmental protectant insect that based on recent studies induces apoptosis in liver and colorectal carcinoma cells through the activation of caspase 3, 8, and 9 and ultimately inhibits the growth of cancer cells. Purpose This study was designed to evaluate the selective apoptotic effect of the n-hexane BSFL extract (BSFLE) on skin mitochondria. Materials and Methods The mitochondria isolated from melanoma cells were treated with various concentrations (1500, 3000, and 6000 µg/ml) of n-hexane BSFLE Then MTT viability assay, ROS determination, Mitochondrial Membrane Potential (MMP), mitochondrial swelling, cytochrome c release determination, and % apoptosis were performed. Results MTT assay showed that different concentrations of n-hexane BSFLE significantly (P < 0.05) decreased the SDH activity in cancerous skin mitochondria with the IC50. The ROS production and mitochondrial swelling results also showed that all concentrations of BSFL extracts significantly increased. MMP decline and the release of cytochrome c in cancer groups mitochondria. BSFLE increased apoptosis on melanoma cells. Discussion and Conclusion It is suggested that n-hexane BSFLE compounds selectively induce a cascade of proapoptotic events that are probably defective in cancer cells. Most of these compounds target the mitochondrial transient pore caused by disruption of the mitochondrial respiratory chain. These events lead to disruption of the temporary permeability of mitochondria, swelling of mitochondria and finally the formation of apoptosome in the cytosol.

Mealworm larvae and black soldier fly larvae as novel protein supplements for cattle consuming low-quality forage.

The global population is projected to increase, indicating that there will be greater demand for animal protein to meet the associated food needs. This demand will place additional pressure on livestock systems to increase output while also minimizing natural resource inputs. Insect protein has emerged as a potential alternative to conventional protein feeds, such as soybean meal. Mealworm larvae (MWL; Tenebrio molitor) have been studied in poultry and swine as an alternative protein source; however, there is no research currently evaluating MWL for cattle. Black soldier fly larvae (BSFL; Hermetia illucens) have also received attention for their potential use in livestock feed due to their scalability and nutritional value, but research in cattle is limited. The objective of this study was to evaluate the effects of whole-dried MWL and defatted BSFL as protein supplements for cattle consuming forage. Five ruminally cannulated steers were utilized in a 5 × 5 Latin square experiment to determine how MWL and BSFL supplementations affect forage utilization. Steers consuming ad libitum low-quality forage (76.5% neutral detergent fiber [NDF], 4.2% crude protein) were provided one of the five treatments each period: 1) control with no supplement (CON), 2) soybean meal (CONV), 3) BSFL, 4) MWL, or 5) 50/50 by-weight blend of BSFL and MWL (MIX). All treatments were provided at 100 mg N/kg BW and periods included 8 d for treatment adaptation, 5 d for intake and digestion, and 1 d for ruminal fermentation measures. Protein supplementation stimulated forage organic matter intake (FOMI; P ≤ 0.01) relative to CON (3.28 kg/d). There was a significant difference in FOMI (P ≤ 0.01) between BSFL (4.30 kg/d) and CONV (4.71 kg/d), but not between CONV and MWL (P = 0.06, 4.43 kg/d). Total digestible OM intake (TDOMI) was also stimulated by the provision of protein (P ≤ 0.01), from 1.94 kg/d for CON to an average of 3.24 kg/d across protein supplements. Organic matter digestibility (OMD) and NDF digestibility (NDFD) were not affected by treatment (P ≥ 0.37), for an average OMD of 66.5% and NDFD of 62.7%. There was also no treatment effect on ruminal volatile fatty acid (P = 0.96) or ammonia-N (P = 0.22) concentrations. These data indicate that MWL may stimulate forage utilization by beef cattle to a greater extent than BSFL, but both are viable protein supplements.

Effects of dietary defatted black soldier fly (Hermetia illucens) larvae meal substituting fish meal on growth, antioxidative capacity, immunity, intestinal histology and microbiota of juvenile Chinese mitten crab (Eriocheir sinensis)

This study evaluated the effects of replacing dietary fish meal (FM) with defatted black soldier fly (Hermetia illucens) larvae meal (DBSFLM) on growth, non-specific immunity, antioxidative capacity, intestinal histology and microbiota of juvenile Chinese mitten crab (Eriocheir sinensis). A control diet was designed to contain 200 g/kg FM (Con), then 25 %, 50 %, 75 %, and 100 % of dietary FM was replaced by DBSFLM, referring to DBSFLM25, DBSFLM50, DBSFLM75 and DBSFLM100, respectively. The five isoproteic and isolipidic diets were fed to crab (7.15 ± 0.10 g) for 8 weeks. The results indicated that the final weight, weight gain, feed conversion ratio and survival of DBSFLM25 and DBSFLM50 groups all reached the same level as Con (P > 0.05). The proper DBSFLM replacement on WG and FCR from broken line model were 49.70 % and 52.90 %, respectively. For immune enzyme activity, ACP, ALP, and LZM activities showed a trend of first increasing and then decreasing, the DBSFLM50 group had the highest activity, and the DBSFLM100 group was significantly lower than the DBSFLM50 group (P < 0.05). In terms of antioxidant capacity, the T-AOC, T-SOD, GSH-Px activities and MDA content of DBSFLM25 DBSFLM50 and DBSFLM75 groups all shows no significant difference with Con (P > 0.05), the DBSFLM100 group has the lowest antioxidant enzyme activities and highest MDA content. The intestinal number of folds and folds height in DBSFLM25 and DBSFLM50 groups reached the same level as Con (P > 0.05). The abundance of intestinal harmful bacteria Vibrio was enhanced with the increase of dietary DBSFLM level (P < 0.05). In conclusion, the recommended level of replacing FM with DBSFLM was at 50 % (100 g/kg) without negative effect on growth, non-specific immunity, antioxidative capacity, intestinal histology and microbiota of Chinese mitten crab.

Partial replacement of soybean with alternative protein sources: Effects on meat quality, sensory attributes, and fatty acids and amino acids content of breast meat of a local chicken strain.

The environmental sustainability of soybean cultivation has been questioned as it has been linked to deforestation, eutrophication, pesticide use, and carbon dioxide footprint. Agri-industrial byproducts and black soldier fly (BSF) larvae meal are promising alternative protein sources that can be used to partly replace soybean in broiler diets. The present study aimed to investigate the effect of partial replacement of soybeans with agro-industrial by-products with or without the addition of BSF dried larvae meal on the meat quality, fatty acid and amino acid content, and sensory traits of breast meat of local chickens. A total of 252 one-day-old mixed-sex chicks from the Anadolu-T pure dam line were randomly assigned to 1 of 3 diets; a soybean-based Control diet, a diet in which soybean meal was partly replaced (SPR) with brewers' dried grain, sunflower seed meal, and wheat middlings and an SPR + BSF diet in which 5% of BSF dried larva meal was added to the SPR diet. All birds were slaughtered at a commercial slaughterhouse at 55 days and breast and drumstick muscles were sampled for meat quality analysis from 18 chickens/dietary treatments. No significant effects of diets were observed for the pH24 and lightness, redness, and yellowness of breast and leg meats. Thawing loss significantly decreased and cooking loss increased in the breast meat of chickens fed the SPR + BSF compared with those fed Control and SPR diets. Diets did not affect either texture profile or consumer sensory properties of breast meat. The chickens fed the SPR + BSF had the highest total saturated fatty acid and lower polyunsaturated fatty acid content in breast meat than those fed the Control and SPR diets. The essential and nonessential amino acid content of breast meat decreased by the SPR diet compared with the SPR + BSF diet. The chickens fed SPR + BSF diet had higher values of tasty, aromatic, and umami-related amino acids than those fed SPR and Control diets. In conclusion, the results of the present study indicated that agri-industrial byproducts with or without BSF larvae meal could be used to partially replace soybean meal in broiler diets without affecting technological meat quality traits. The addition of BSF larvae meal to the diet along with agri-industrial by-products improved the amino acid content of the breast meat of chickens but reduced polyunsaturated fatty acid levels.

Impact of Combinations of Diet and Larval Rearing Temperature on Duration of Larval, Pre Pupal and Pupal Stages of Black Soldier Fly, Hermetia illucens L. (Stratiomyidae: Diptera)

As the world’s population increases day by day, the amount of organic waste generated also increases posing huge great threat to mankind and the environment. The black soldier fly is known for its capacity to convert organic wastes to nutrient rich manure and in the process the larvae accumulate proteins from the wastes. Hence, the fly finds its place as an ingredient in poultry feed, animal/pet food and fish feed. Since the fly is reared commercially, studies on rearing conditions would help scientists and the industry. The present study was carried out in the Black soldier fly breeding laboratory in Agricultural Research Institute, Rajendgranagar, Hyderabad during 2023-24 with an aim to study the impact of diet and temperatures on the developmental periods of larvae, prepupae and pupae in a two factorial completely randomized design with four diets viz., chicken feed, sesamum cake, groundnut cake and Gainsville diet at five temperatures viz.,150C, 200C, 250C, 350C and 420C. Results revealed that diet and temperature had significant impact on durations of larva, prepupa and pupa and the interactions of diet and temperature were also significant. The Gainsville diet at 200C,250C and 350C recorded least larval duration while sesamum cake at 150̊C recorded longest larval and prepupal duration. Shortest pupal period was noticed in groundnut cake at 150C and longest pupal period in sesamum cake at 250C.

Principle Investigation and Method Standardization of Inhibition Zone Assay Based on Antimicrobial Peptides Extracted from Black Soldier Fly Larvae.

The black soldier fly is a valuable resource insect capable of transforming organic waste while producing antimicrobial peptides (AMPs). The inhibition zone assay (IZA) is a method used to demonstrate the antimicrobial activity of AMPs. This study aimed to examine the experimental principles and establish a standardized IZA method. Results indicated that the AMPs extract consisted of proteins ranging in molecular weights from 0 to 40 kDa. The AMPs diffused radially on an agar plate through an Oxford cup. The diffusion radius was influenced by the concentration and volume of the AMPs but ultimately determined by the mass of the AMPs. The swabbing method was found to be effective for inoculating bacteria on the agar plate. Among the conditions tested, the plate nutrient concentration was the most sensitive factor for the IZA, followed by bacterial concentration and incubation time. Optimal conditions for the IZA included a nutrient plate of 0.5× TSA, a bacterial concentration of 106 CFU/mL, and an incubation time of 12 h, with oxytetracycline (OTC) at 0.01 mg/mL serving as the positive control. The antimicrobial-specific activity of AMPs could be standardized by the ratio of inhibition zone diameters between AMPs and OTC. These findings contribute to the standardization of the IZA method for profiling the antimicrobial activity of AMPs.