Allomyrina Dichotoma Larvae Research Articles

Prevention of UVB-Induced Photoaging by an Ethyl Acetate Fraction from Allomyrina dichotoma Larvae and Its Potential Mechanisms in Human Dermal Fibroblasts.

Allomyrina dichotoma larvae (ADL) is an insect type that is used ethnopharmacologically to treat various diseases; however, its use as an antiaging treatment has not been widely studied. Previously, we found that an ethyl acetate (EA) fraction derived from an ADL extract (ADLE) has a high polyphenol content and antioxidant properties. In this study, we identified the underlying molecular mechanism for the protective effect of the EA fraction against UVB-induced photodamage in vitro and ex vivo. UVB treatment increased intracellular reactive oxygen species levels and DNA damage; the latter of which was significantly decreased following cotreatment with the EA fraction. Biological markers of aging, such as p16INK4a, p21WAF1, and senescence-associated β-gal levels, were induced by UVB treatment but significantly suppressed following EA-fraction treatment. UVB-induced upregulation of matrix metalloproteinase (MMP)-1 and downregulation of COL1A1 were also reversed by EA-fraction treatment in both cells and a 3D skin model, which resulted in increased keratin and collagen deposition. Moreover, EA-fraction treatment inhibited the phosphorylation of MAPKs (p38, ERK, and JNK) and nuclear factor (NF-)-kB and decreased the levels of inflammatory cytokines in UVB-treated cells. The results indicate that an EA fraction from ADLE ameliorates UVB-induced degradation of COL1A1 by inhibiting MMP expression and inactivating the MAPK/NF-κB p65/AP-1 signaling pathway involved in this process.

P06-038-23 Effect of Allomyrina dichotoma Larvae Ethyl Acetate Fraction on Ultraviolet B-Induced Aging in Human Diploid Fibroblasts

P06-038-23 Effect of Allomyrina dichotoma Larvae Ethyl Acetate Fraction on Ultraviolet B-Induced Aging in Human Diploid Fibroblasts

AGL9: A Novel Hepatoprotective Peptide from the Larvae of Edible Insects Alleviates Obesity-Induced Hepatic Inflammation by Regulating AMPK/Nrf2 Signaling.

In this study, we investigated the anti-obesity properties of the novel peptide Ala-Gly-Leu-Gln-Phe-Pro-Val-Gly-Arg (AGL9), isolated from the enzymatic hydrolysate of Allomyrina dichotoma larvae. To investigate the preventive effects of AGL9 against hepatic steatosis and its possible mechanisms of action, we established an nonalcoholic fatty liver disease (NAFLD) model by feeding C57BL/6 mice a high-fat diet. NAFLD mice were administered 100 mg/kg AGL9 and 60 mg/kg orlistat via gavage (10 mL/kg) for 5 weeks, followed by the collection of blood and liver tissues. We found that AGL9 normalized the levels of serum alanine aminotransferase, aspartate aminotransferase, triglyceride, total cholesterol, high-density lipoprotein, very low-density lipoprotein (LDL)/LDL, adiponectin, and leptin in these mice. Additionally, AGL9 activated the protein-level expression of 5′ AMP-activated protein kinase and acetyl-CoA carboxylase phosphorylation and the transcript-level expression of sterol regulatory element-binding protein-1c, fatty acid synthase, superoxide dismutase, glutathione peroxidase, glucocorticoid receptor, nuclear respiratory factor 2, tumor necrosis factor-α, interleukin-1β, interleukin-6, and monocyte chemoattractant protein-1 in hepatocytes. These results showed that AGL9 exhibited hepatoprotective effects by attenuating lipid deposition, oxidative stress, and inflammation via inhibition of AMPK/Nrf2 signaling, thereby reducing the production of hepatic proinflammatory mediators and indicating AGL9 as a potential therapeutic strategy for NAFLD.

Identification and improvement of volatile profiles of Allomyrina dichotoma larvae by fermentation with lactic acid bacteria

The larva of Allomyrina dichotoma is an edible insect that is widely consumed in Asia. A. dichotoma larvae are reported to be beneficial to human health. They have a high nutritional value, so consumer demand is increasing. However, A. dichotoma larvae have a unique off-flavor that adversely affects consumer preference. In this study, HS-SPME/GC-MS was used to identify the unique volatile profiles and potential off-flavor volatiles in A. dichotoma larvae. Also, fermentation process of A. dichotoma larvae with various lactic acid bacteria was applied to improve their safety and overall flavor. As a result, a total of 36 volatiles were identified from A. dichotoma larvae. Lactic acid fermentation showed a decrease in indole, pyrazines, 1-octen-3-ol, and 3-octanol and an increase of propanol, ethanol, and acetone. These changes in volatiles may improve overall flavor of the larvae by reducing a fecal, roasted, earthy, mushroom, and animal odors and by enhancing sweet or bitter flavors. The volatile profiles of A. dichotoma larvae provide useful information for further studies focusing on reducing their off-flavor.

Substitution of Phosphate and ISP by Allomyrina dichotoma Larvae Powder in Emulsion Sausage

Substitution of Phosphate and ISP by Allomyrina dichotoma Larvae Powder in Emulsion Sausage

Exploring the Role of a Novel Peptide from Allomyrina dichotoma Larvae in Ameliorating Lipid Metabolism in Obesity.

The aim of this study was to identify an anti-obesity peptide from Allomyrina dichotoma and investigate the lipid metabolic mechanism. Enzymatically hydrolyzed A. dichotoma larvae were further separated using tangential flow filtration and consecutive chromatographic processes. Finally, an anti-obesity peptide that showed the highest inhibitory effect on lipid accumulation was obtained, and the sequence was Glu-Ile-Ala-Gln-Asp-Phe-Lys-Thr-Asp-Leu (EIA10). EIA10 decreased lipid aggregation in vitro and significantly reduced the accumulation of body weight gain, liver weight, and adipose tissue weight in high-fat-fed mice. Compared with the control group, the levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL), insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) in the high-fat diet (HFD) group increased significantly, and the content of high-density lipoprotein cholesterol (HDL) in the serum decreased significantly. On the contrary, the levels of TC, TG, and insulin in the EIA10 group decreased significantly, and the HDL content increased significantly compared with the HFD group. Additionally, EIA10 dramatically decreased mRNA and protein levels of transcription factors involved in lipid adipogenesis. Taken together, our results suggest that EIA10 could be a promising agent for the treatment and prevention of obesity.

Thermal stability and rheological properties of heat-induced gels prepared using edible insect proteins in a model system

We investigated the thermal stability and rheological properties of heat-induced gels prepared using edible insect proteins originating from various edible insect species: Tenebrio molitor L., Protaetia brevitarsis larvae, and Allomyrina dichotoma larvae. The protein solubility and pH of the heat-induced gel prepared from A. dichotoma exhibited the highest value (P < 0.05) among all samples. The redness and yellowness (P < 0.05); water holding capacity (P < 0.05); and springiness, cohesiveness, gumminess, and chewiness (P < 0.05) of the heat-induced gel from P. brevitarsis showed the highest values. The apparent viscosity of the gel from P. brevitarsis was higher than that of the other samples (P < 0.05). The storage modulus (G′) and loss modulus (G″) of the gel from T. molitor were lower than those of the gel from P. brevitarsis and A. dichotoma. Compared to the edible insect proteins obtained from T. molitor, those from P. brevitarsis and A. dichotoma were more heat stable, with a more complex structure, and showed various peak temperatures. P. brevitarsis and T. molitor gels displayed the highest and lowest emulsion capacity, respectively (P < 0.05). Thus, the gels from P. brevitarsis and A. dichotoma proteins exhibited excellent processing functionalities as heat-induced gels.

장수풍뎅이 유충 단백가수분해물의 제조 및 항산화 활성

장수풍뎅이 유충 단백가수분해물의 제조 및 항산화 활성

장수풍뎅이 유충 유지 및 탈지분말의 품질 특성

장수풍뎅이 유충 유지 및 탈지분말의 품질 특성

Alleviation of Hippocampal Endoplasmic Reticulum Stress by Allomyrina dichotoma Larvae Extract.

In the brain, endoplasmic reticulum (ER) stress results in synaptic dysfunction and eventually leads to neurodegeneration. Allomyrina dichotoma larvae are a Chinese ethnomedicine and are widely used in East Asia. In the present study, we investigated the ability of ethanol extract of A. dichotoma larvae (ADE) to improve synaptic structure and function by activating unfolded protein response (UPR) under ER stress in animal and neuron culture models. ER stress was induced in obese mice fed a high fat diet (HFD) or by treating dissociated cultures of rat embryonic (E19) hippocampal neurons with tunicamycin (TM). Western blot and real-time or conventional RT-PCR were performed to analyze the expressions of ER stress marker proteins. In dissociated hippocampal cultures, immunocytochemistry was performed for synaptic proteins, and cultures were stained with styryl dye FM1-43 to assess presynaptic activities. In HFD-fed obese mice, ADE efficiently reduced the expressions of ER stress markers, such as, xbp-1, chop, atf4, erdi4, and eIf2a, and those of the ER chaperone/foldases Bip/grp78, Ero-1l, and PDI. Unconventionally spliced xbp-1s mRNA was not detected. In primary rat hippocampal cultures under ER stress, ADE significantly lowered the nuclear expression of CHOP, inhibited the downregulations of postsynaptic proteins, such as, GluN2A, GluN2B, and PSD-95, and maintained the pool size of recycling presynaptic vesicles. The study shows that ADE potently suppressed the induction of ER stress and maintained the structure and function of hippocampal neurons, and suggests that ADE is a potentially valuable food supplement and preventive therapeutic for ER stress-related nervous disorders.

새로운 식품원료로 등록된 식용곤충의 영양성분 비교 분석

본 연구에서는 갈색거저리, 흰점박이꽃무지 및 장수풍뎅이 유충의 영양성분을 비교분석하였고, 이를 통해 식용곤충 이용 시 곤충 선택 기준확립에 기초 자료로 활용될 수 있을 것으로 사료된다. 3종 식용곤충의 영양성분 비교결과, 조단백질, 조지방, 탄수화물은 각각 흰점박이꽃무지, 갈색거저리 및 장수풍뎅이 유충에서 가장 높았다. 아미노산 함량 비교 분석 결과, 총 아미노산 함량과 필수 아미노산의 함량은 갈색거저리 유충에서 가장 높았다. 지방산의 조성은 갈색거저리와 흰점박이꽃무지 유충이 유사하였으며, 이들은 장수풍뎅이 유충에 비해 불포화 지방산 함량이 높았다. 또한, 무기질 함량의 비교 분석 결과, 칼슘과 철은 장수풍뎅이 유충에서 가장 높은 반면 인과 칼륨은 흰점박이꽃무지 유충에 가장 많이 함유되어 있었다. 위와 같은 결과를 통해 각각의 곤충이 함유하는 영양성분에 따라 노인, 어린이 및 임산부 등 다양한 영양 요구를 가지는 대상에 따라 필요한 곤충을 선택하여 섭취가 가능할 것이며 식용곤충을 다양하게 조합하는 경우 보다 풍부한 영양분을 섭취할 수 있을 것으로 사료된다. In this study, the nutritional components of Tenebrio molitor, Protaetia brevitarsis, and Allomyrina dichotoma larvae, which have been registered as novel foods, were analyzed and compared to expand the diversity of selection criteria for edible insects. The contents of crude components, amino acids, fatty acids, and minerals were analyzed. According to the results of comparative analysis of edible insects, crude proteins were abundant in all three kinds of insects. The content of crude fat was the highest in T. molitor, and the content of carbohydrate was the highest in A. dichotoma. When comparing the composition of amino acids, total amino acid content and essential amino acids were the highest in T. molitor larvae. In T. molitor and P. brevitarsis larvae, the compositions of fatty acids were similar, with higher amounts of unsaturated fatty acids than in A. dichotoma. In terms of mineral content, A. dichotoma contained the highest amounts of calcium and iron, whereas P. brevitarsis contained the highest amounts of phosphorus and potassium. With these results, it is expected that edible insects could be selected according to nutritional demand. In addition, multiple combinations of edible insects will offer a richer intake of nutrients.

Allomyrina Dichotoma Larvae Regulate Food Intake and Body Weight in High Fat Diet-Induced Obese Mice Through mTOR and Mapk Signaling Pathways.

Recent evidence has suggested that the Korean horn beetle (Allomyrina dichotoma) has anti-hepatofibrotic, anti-neoplastic, and antibiotic effects and is recognized as a traditional medicine. In our previous works, Allomyrina dichotoma larvae (ADL) inhibited differentiation of adipocytes both in vitro and in vivo. However, the anorexigenic and endoplasmic reticulum(ER) stress-reducing effects of ADL in obesity has not been examined. In this study, we investigated the anorexigenic and ER stress-reducing effects of ADL in the hypothalamus of diet-induced obese (DIO) mice. Intracerebroventricular (ICV) administration of ethanol extract of ADL (ADE) suggested that an antagonizing effect on ghrelin-induced feeding behavior through the mTOR and MAPK signaling pathways. Especially, ADE resulted in strong reduction of ER stress both in vitro and in vivo. These findings strongly suggest that ADE and its constituent bioactive compounds are available and valuable to use for treatment of various diseases driven by prolonged ER stress.

Toxicological evaluation of genotoxicity and 28-day oral toxicity study on freeze-dried powder of Allomyrina dichotoma larvae

Edible insects have noteworthy potential as an alternative food material because of their economical efficiency and nutritional value. This study was conducted to evaluate toxicological effects on in vitro and in vivo experiments for Allomyrina dichotoma (A. dichotoma), whose larvae are known for containing biologically valuable functions. The present study included testings for genotoxicity and 28-day repeated oral toxicity. The genotoxic potential was evaluated by a standard battery test. To evaluate the repeated dose toxicity, the freeze-dried powder of A. dichotoma larvae was orally administered to Sprague–Dawley (SD) rats at dose levels of 0, 250, 850 and 2500mg/kg body weight per day for 28days. The powder exhibited no mutagenic or clastogenic effects based on the results of in vitro and in vivo genotoxicity tests. Also, there were no treatment-related changes or findings on the repeated oral toxicity in rats after 28days oral administration. In conclusion, the results of these experiments suggest that the NOAEL (No Observed Adverse Effect Level) of the freeze-dried powder from A. dichotoma larvae was determined to be 2500mg/kg/day or more in both sexes of SD rats.

Subchronic Oral Dose Toxicity of Freeze-dried Powder of Allomyrina dichotoma Larvae.

The objective of this study was to investigate the toxicological information of freeze-dried powder from Allomyrina dichotoma (A. dichotoma) larvae as a food ingredient. The powder, suspended in distilled water, was administered once daily by oral gavage to four groups of Sprague-Dawley (SD) rats at dose levels of 0 (vehicle control), 250, 850, and 2500 mg/kg/day. After 13 wks of repeated administration, the standard toxicological parameters such as mortality, clinical signs, body weight, food consumption, ophthalmologic examination, clinical pathology, organ weights and macro/microscopic examination were applied for assessment of general toxicity. In addition, serum IgE and histamine levels were determined to evaluate allergenicity. The freeze-dried powder from A. dichotoma larvae did not produce treatmentrelated changes or findings in any toxicological parameters in either sex of any dosed groups except for slight increases in serum histamine levels at 2500 mg/kg/day. The changes were considered not to be adverse since the magnitude was minimal. In conclusion, the NOAEL (No Observed Adverse Effect Level) of the freeze-dried powder from A. dichotoma larvae was determined to be 2500 mg/kg/day or more in both sexes of SD rats and it is considered a candidate to be edible material.

장수풍뎅이 유충의 간보호 효능 및 항암활성

Beetle larvae have been used as a traditional medicine to treat various human liver diseases. To prove the liver protective function of Allomyrina dichotoma larvae (ADL), we induced liver damage by the intraperitoneal injection of a hepatotoxic reagent, diethylnitrosamine (DEN), to C3H/HeN male mice and orally administered freeze-dried ADL powder. ADL powder lessened DEN-induced hepatotoxicity considering the reduced signs of acute and chronic hepatotoxicities, such as the ALP level in the blood serum, TUNEL-positive hepatocytes, ductural reactions, steatotic hepatocytes, and collagen deposition of the Masson’s trichrome staining. In addition to hepatoprotection, the anti-cancer activity of ADL has been examined. The ADL powder was extracted with ethanol and then fractionated with hexane, ethyl acetate, and water by a solvent partition technique. The ethyl acetate fraction showed cytotoxicity to various cancer cells through induction of apoptosis and necrosis, as well as the perturbed metabolism of the cancer cell to trigger autophagy. Collectively, ADL contains bioactive substances that can protect hepatocytes from toxic chemicals and trigger cell death in cancer cells. Thus, further purification and analyses of ADL fractions could lead to the identification of novel bioactive compounds.

Allomyrina dichotoma (Arthropoda: Insecta) larvae confer resistance to obesity in mice fed a high-fat diet.

To clarify the anti-obesity effect of Allomyrina dichotoma larvae (ADL), we previously reported that ADL block adipocyte differentiation on 3T3-L1 cell lines through downregulation of transcription factors, such as peroxisome proliferator-activated receptor-γ (PPARG) and CCAAT/enhancer binding protein-α (CEBPA). In this study, we tested whether ADL prevent obesity in mice fed a high-fat diet (HFD) and further investigated the mechanism underlying the effects of ADL. All mice were maintained on a normal-fat diet (NFD) for 1 week and then assigned to one of five treatment groups: (1) NFD; (2) HFD; (3) HFD and 100 mg·kg−1·day−1 ADL; (4) HFD and 3000 mg·kg−1·day−1ADL; or (5) HFD and 3000 mg·kg−1·day−1 yerba mate (Ilex paraguariensis, positive control). ADL and yerba mate were administered orally daily. Mice were fed experimental diets and body weight was monitored weekly for 6 weeks. Our results indicated that ADL reduced body weight gain, organ weight and adipose tissue volume in a dose-dependent manner. Body weight gain was approximately 22.4% lower compared to mice fed only HFD, but the difference did not reach the level of statistical significance. Real-time polymerase chain reaction (PCR) analysis revealed that gene expression levels of PPARG, CEBPA and lipoprotein lipase (LPL) in the epididymal fat tissue of HFD-fed mice receiving 3000 mg·kg−1·day−1 ADL were reduced by 12.4-, 25.7-, and 12.3-fold, respectively, compared to mice fed HFD only. Moreover, mice administered ADL had lower serum levels of triglycerides and leptin than HFD-fed mice that did not receive ADL. Taken together our results suggest that ADL and its constituent bioactive compounds hold potential for the treatment and prevention of obesity.

Effects of solvent fractions of Allomyrina dichotoma larvae through the inhibition of in vitro BACE1 and β‐amyloid(25–35)‐induced toxicity in rat pheochromocytoma PC12 cells

AbstractAmyloid‐β peptide (Aβ) generation initiated by β‐site amyloid precursor protein cleaving enzyme 1 BACE1 is a critical cause of Alzheimer's disease. In the course of our ongoing investigation of natural anti‐dementia resources, the ethyl acetate (EtOAc) fraction exerted strong BACE1‐specific inhibition with the half maximal inhibitory concentration (IC50) value of 9.2 × 10−5 μg/mL. Furthermore, Aβ(25–35)‐induced cell death was predominantly prevented by the EtOAc fraction of Allomyrina dichotoma larvae through diminishing of cellular oxidative stress and attenuating apoptosis by inhibiting caspase‐3 activity. Taken together, the present study demonstrated that A. dichotoma larvae possess novel neuroprotective properties not only via the selective and specific inhibition of BACE1 activity but also through the alleviation of Aβ(25–35)‐induced toxicity, which may raise the possibility of therapeutic application of A. dichotoma larvae for preventing and/or treating dementia.

Fatty Acid and Volatile Oil Compositions of Allomyrina dichotoma Larvae

Thirty-two different volatile oils were identified from Allomyrina dichotoma (A. dichotoma) larvae by gas chromatography/mass spectrometry (GC/MS). The major volatile components were 2,2,4-trimethyl-3-carboxyisopropyl pentanoic acid isobutyl ester (5.83%), phenol,2,6-bis(a,a-dimethyl ethyl)-4-(1-methyl-1-phenylethyl) (5.72%), heptacosane (5.49%) and phenol,2,4-bis(1-methyl-1-phenylethyl) (5.47%). The composition of the fatty acids in A. dichotoma larvae was also determined by gas chromatography (GC) and fourteen constituents were identified. Oleic acid (19.13%) was the most abundant fatty acid followed by palmitic acid (12.52%), palmitoleic acid (3.71%) and linoleic acid (2.08%) in 100 g of A. dichotoma larvae on a dry weight basis. The quantity of unsaturated fatty acids (64.00%) were higher than that of saturated ones (36.00%). The predominant fatty acids in A. dichotoma consist of monounsaturated fatty acid (MUFA, 57.70%) such as oleic acid, myristoleic acid and palmitoleic acid, followed by saturated fatty acids (36.00%) and polyunsaturated fatty acids (PUFA, 6.50%). In particular, the presence of essential fatty acids, such as linoleic (5.30%) and linolenic acid (0.40%) give A. dichotoma larvae considerable nutritional and functional value and it may be a useful source for food and/or industrial utilization.

Purification and characterization of a lectin from the beetle, Allomyrina dichotoma.

A lectin was purified from the hemolymph of Allomyrina dichotoma larvae by affinity chromatography on acid-treated Sepharose 4B. The purified lectin showed two protein bands on polyacrylamide gel electrophoresis. These two lectin bands (allo A-I and -II) were separated by DEAE-Cellulofine column chromatography. By gel filtration on Sephadex G-100, the molecular weights of allo A-I and -II were estimated to be 65,000 and 66,500, respectively. On the other hand, by SDS-polyacrylamide gel electrophoresis after cross-linking of subunits with glutaraldehyde, they are estimated to be 38,000 and 39,000, respectively. On SDS-polyacrylamide gel electrophoresis, it was proved that both allo A-I and -II lectin consisted of two subunits, respectively. The molecular weights were 17,500 and 20,000 for allo A-I, and 19,000 and 20,000 for allo A-II. The isoelectric points of allo A-I and -II were estimated to be 6.4 and 5.9, respectively. On double immunodiffusion, allo A-I and -II gave single precipitin lines, which fused completely with each other, against the antibody to crude allo A. The hemagglutinating activity of allo A-I and -II was inhibited only by beta-linked D-galactose such as lactose and lactulose.