Dietary Inclusion of Yellow Mealworms (T. molitor) and Lesser Mealworms (A. diaperinus) Modifies Intestinal Microbiota Populations of Diet-Induced Obesity Mice.

BACKGROUND: Insect-based proteins are high-quality alternatives to support the shift toward more sustainable and healthy diets. Additionally, insects contain chitin and have unique fatty acid profiles. Studies have shown that mealworms may beneficially affect metabolism, but limited information is known regarding their effects on gut microbiota. OBJECTIVES: We determined the effects of defatted yellow mealworm (Tenebrio molitor) and whole lesser mealworm (Alphitobius diaperinus) meals on the intestinal microbiota of diet-induced obesity mice. METHODS: Male C57BL/6J mice were fed a high-fat diet (HFD; 46% kcal) to induce obesity. Obese mice were then randomly assigned to treatments (n = 10/group) and fed for 8 wk: HFD, HFD with casein protein; B50, HFD with 50% protein from whole lesser mealworm; B100, HFD with 100% protein from whole lesser mealworm; Y50, HFD with 50% protein from defatted yellow mealworm; Y100, HFD with 100% protein from defatted yellow mealworm. Lean mice (n = 10) fed a low-fat-diet (10% kcal) were included. Fresh feces were collected at baseline and every 2 wk, with cecal digesta collected at kill. Fecal and cecal DNA was analyzed for microbiota using 16S rRNA MiSeq Illumina sequencing. RESULTS: In feces and cecal digesta, mice fed mealworms had greater (P < 0.05) bacterial alpha diversity, with changes occurring in a time-dependent manner (P < 0.05). Beta diversity analyses of cecal samples showed a clear separation of treatments, with a time-based separation shown in fecal samples. Widespread microbial differences were observed, with over 45 genera altered (P < 0.05) by diet in cecal digesta. In feces, over 50 genera and 40 genera were altered (P < 0.05) by diet and time, respectively. CONCLUSION: Mealworm consumption changes the intestinal microbiota of obese mice, increasing alpha diversity measures and shifting bacterial taxa. More investigation is required to determine what mealworm components are responsible and how they may be linked with the metabolic benefits observed in mealworm-fed mice.

Yellow Mealworm (Tenebrio molitor) and Lesser Mealworm (Alphitobius diaperinus) Proteins Slowed Weight Gain and Improved Metabolism of Diet-Induced Obesity Mice.

BACKGROUND: High-protein diets not only meet amino acid needs but also modulate satiety and energy metabolism. Insect-based proteins are sustainable, high-quality proteins. Mealworms have been studied, but limited information is known about their ability to impact metabolism and obesity. OBJECTIVE: We determined the effects of defatted yellow mealworm (Tenebrio molitor)- and whole lesser mealworm (Alphitobius diaperinus)-based proteins on the body weight (BW), serum metabolites, and liver and adipose tissue (AT) histology and gene expression of diet-induced obesity mice. METHODS: Male C57BL/6J mice were fed a high-fat diet (HFD; 46% kcal) to induce obesity and metabolic syndrome. Obese mice were then assigned to treatments (n = 10/group) and fed for 8 wk: HFD: HFD with casein protein; B50: HFD with 50% protein from whole lesser mealworm; B100: HFD with 100% protein from whole lesser mealworm; Y50: HFD with 50% protein from defatted yellow mealworm; Y100: HFD with 100% protein from defatted yellow mealworm. Lean mice (n = 10) fed a low-fat-diet (LFD; 10% kcal) were included. Longitudinal food intake, BW, body composition, and glucose response were measured. At time of killing, serum metabolites, tissue histopathology and gene expression, and hepatic triglycerides were analyzed. RESULTS: After 8 wk, HFD, B50, and B100 had greater (P < 0.05) weight gain than LFD, whereas Y50 and Y100 did not. Y50, B100, and Y100 had a lower (P < 0.05) BW change rate than HFD. Mealworm-based diets led to increased (P < 0.05) serum high-density lipoprotein (HDL) and reduced (P < 0.05) serum low-density lipoprotein (LDL) concentrations and reduced (P<0.05) LDL/HDL ratio. Mealworm-based diets led to increased (P < 0.05) hepatic expression of genes related to energy balance, immune response, and antioxidants and reduced (P < 0.05) AT expression of genes associated with inflammation and apoptosis. Mealworm-based diets altered (P < 0.05) hepatic and AT expression of glucose and lipid metabolism genes. CONCLUSIONS: In addition to serving as an alternative protein source, mealworms may confer health benefits to obese patients.

Amino acid digestibility and protein quality of mealworm-based ingredients using the precision-fed cecectomized rooster assay.

Mealworms may serve as an alternative protein source for pet foods because of their high protein content and low environmental footprint. The amino acid (AA) content and protein quality of mealworm-based ingredients may vary depending on their composition and processing, however, so testing is required. Our objective was to measure the AA composition, AA digestibility, and protein quality of mealworm-based ingredients using the precision-fed cecectomized rooster assay. The University of Illinois Institutional Animal Care and Use Committee approved all animal procedures prior to experimentation. Sixteen cecectomized roosters (4 roosters per substrate) were randomly allotted to one of four test substrates: 1) whole lesser mealworm (A. diaperinus) meal (ADw); 2) defatted lesser mealworm (A. diaperinus) meal (ADd); 3) defatted yellow mealworm (T. molitor) meal (TMd); and 4) hydrolyzed T. molitor protein meal (TMh). Ingredients were provided by Ynsect, France. After 26 h of feed withdrawal, roosters were tube-fed test substrates. Following crop intubation, excreta samples were collected for 48 h. Endogenous loss corrections for AA were made by using five additional cecectomized roosters. All data were analyzed using SAS version 9.4. All substrates had high AA digestibilities, with all indispensable AA digestibilities being >90% with the exception of histidine (87.9% to 91.1%) and valine (77.9% to 79.7%). Amino acid digestibilities were not different among substrates (P > 0.05). Digestible indispensable AA score (DIAAS)-like values were calculated to determine protein quality according to Association of American Feed Control Officials (AAFCO) nutrient profiles, The European Pet Food Industry Nutritional Guidelines (FEDIAF) nutritional guidelines, National Research Council (NRC) recommended allowances for adult dogs, adult cats, growing puppies, and growing kittens, and NRC minimal requirements for growing puppies and growing kittens. In general, TMh had the highest and TMd had the lowest DIAAS-like values for most indispensable AA. Methionine (TMh; TMd; ADw) and phenylalanine (ADd) were the first-limiting AA. Our results demonstrate that mealworm-based ingredients are high-quality protein sources. Further research in dogs and cats is necessary to confirm sufficient palatability and digestibility, but these data suggest that they are valuable sources of protein for pet foods.

Mealworms may serve as an alternative protein source for pet foods because of their high protein content and low environmental footprint. The amino acid (AA) content and protein quality of mealworm-based ingredients may vary depending on their composition and processing, however, so testing is required. Our objective was to measure the AA composition, AA digestibility, and protein quality of the following ingredients using the precision-fed cecectomized rooster assay: 1) defatted yellow mealworm (Tenebrio molitor) flour (TMd); 2) hydrolyzed T. molitor proteins (TMh); 3) whole lesser mealworm (Alphitobius diaperinus) flour (ADw); and 4) defatted lesser mealworm (A. diaperinus) flour (ADd). All ingredients had high AA digestibilities, with all indispensable AA digestibilities being >90% with the exception of histidine and valine. Digestible indispensable AA score (DIAAS)-like values were calculated to determine protein quality for adult dogs, adult cats, growing puppies, and growing kittens. In general, TMh had the highest and TMd had the lowest DIAAS-like values for most indispensable AA. Methionine (TMh; TMd; ADw) and phenylalanine (ADd) were the first-limiting AA. Our results demonstrate that mealworm-based ingredients are high-quality protein sources. Dog and cat research is necessary, but these data suggest that they are valuable sources of protein for pet foods.

Design of a VLP-nanovehicle for CYP450 enzymatic activity delivery.

BACKGROUND: The intracellular delivery of enzymes for therapeutic use has a promising future for the treatment of several diseases such as genetic disorders and cancer. Virus-like particles offer an interesting platform for enzymatic delivery to targeted cells because of their great cargo capacity and the enhancement of the biocatalyst stability towards several factors important in the practical application of these nanoparticles. RESULTS: We have designed a nano-bioreactor based on the encapsulation of a cytochrome P450 (CYP) inside the capsid derived from the bacteriophage P22. An enhanced peroxigenase, CYPBM3, was selected as a model enzyme because of its potential in enzyme prodrug therapy. A total of 109 enzymes per capsid were encapsulated with a 70 % retention of activity for cytochromes with the correct incorporation of the heme cofactor. Upon encapsulation, the stability of the enzyme towards protease degradation and acidic pH was increased. Cytochrome P450 activity was delivered into Human cervix carcinoma cells via transfecting P22-CYP nanoparticles with lipofectamine. CONCLUSION: This work provides a clear demonstration of the potential of biocatalytic virus-like particles as medical relevant enzymatic delivery vehicles for clinical applications.

Chemotherapy pro-drug activation by biocatalytic virus-like nanoparticles containing cytochrome P450.

This work shows, for the first time, the encapsulation of a highly relevant protein in the biomedical field into virus-like particles (VLPs). A bacterial CYP variant was effectively encapsulated in VLPs constituted of coat protein from cowpea chlorotic mottle virus (CCMV). The catalytic VLPs are able to transform the chemotherapeutic pro-drug, tamoxifen, and the emerging pro-drug resveratrol. The chemical nature of the products was identified, confirming similar active products than those obtained with human CYP. The enzymatic VLPs remain stable after the catalytic reaction. The potential use of these biocatalytic nanoparticles as targeted CYP carriers for the activation of chemotherapy drugs is discussed.

Substitution of the catalytic metal and protein PEGylation enhances activity and stability of bacterial phosphotriesterase.

Phosphotriesterase, a pesticide-degrading enzyme, from Flavobacterium sp. was cloned and expressed in Escherichia coli. The catalytic zinc ions were replaced by cobalt atoms increasing the catalytic activity of phosphotriesterase on different pesticides. This metal substitution increased the catalytic activity from 1.4 times to 4 times according to the pesticide. In order to explain this catalytic increase, QM/MM calculations were performed. Accordingly, the HOMO energy of the substrate is closer to the LUMO energy of the cobalt-substituted enzyme. The chemical modification of the enzyme surface with poly(ethylene glycol) increased the thermostability and stability against metal chelating agents of both metal phosphotriesterase preparations.