Allergenic characterization of Bomb m 4, a 30 kDa lipoprotein Bombyx mori lipoprotein 6 from silkworm pupa

Neglected but Clinically Relevant Allergens in Korea

PURPOSE OF REVIEW

Allergy diagnostics and immunotherapeutics in Asia heavily rely on imported products from Western countries, raising concerns about the accuracy and efficacy of these products for the management of Asian allergy patients.

RECENT FINDINGS

Recent advancements in allergen research have led to the identification and characterization of novel allergens from indigenous Korean species. While some allergens share homology with well-known allergens, others lack counterparts in imported allergen extracts. Classifying regional allergens in Asia into three categories based on their cross-reactivity with imported allergens offers valuable insights. Highly cross-reactive allergens, such as oak allergens Que m 1 from Quercus mongolica and Que ac 1 from Q. acutissima, can be effectively substituted with the imported allergens. Allergens with partial cross-reactivity, like the Asian needle ant allergen Pac c 3 (Antigen 5), permit limited diagnostic value by the currently available products. Unique allergens, including the Japanese hop allergen Hum j 6 (pectin methylesterase inhibitor) and the silkworm pupa allergen Bomb m 4 (30 kDa hemolymph lipoprotein) lack alternatives in the available product list. Greater attention is needed, particularly for species listed as ecologically invasive in Western regions. Additionally, allergens from domestic fruits and vegetables causing pollen food allergy syndrome require characterization for the development of improved diagnostics.

Comparative analysis of LC-MS/MS and real-time PCR assays for efficient detection of potential allergenic silkworm

The silkworm (Bombyx mori) has long been valued food and feed in East Asia for its abundant nutritional and medicinal attributes, conversely, it can elicit allergic responses in susceptible individuals. Therefore, the development of silkworm detection method is required to avert allergenic incidents. In this study, two methodologies, tandem mass spectrometry (LC-MS/MS) and real-time PCR, were developed to achieve effective silkworm detection. These methods exhibited exceptional sensitivity in identifying silkworm presence in processed foods. Furthermore, model cookies spiked with silkworm were used to validate the sensitivities of LC-MS/MS (0.0005%) and real-time PCR (0.001%). Overall, these techniques were useful for trace silkworm detection in food products; therefore, they may help prevent allergic reactions. To the best of our knowledge, this study represents the first comparison of LC-MS/MS and real-time PCR methods for silkworm detection, marking an important contribution to the field. Data are available from ProteomeXchange under identifier PXD042494.

Purification, Immunological Identification, and Characterization of the Novel Silkworm Pupae Allergen Bombyx mori Lipoprotein 3 (Bomb m 6)

Allergic reactions caused by silkworm pupae greatly limit their utilization, and studies suggest that silkworm pupae proteins of 25-30 kDa may be the principal allergens. To further understand these allergens, we attempted to purify a protein of about 30 kDa by ammonium sulfate salting, pH-graded precipitation, and ion-exchange chromatography. The protein was identified by mass spectrometry and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), western blot, enzyme-linked immunosorbent assays, circular dichroism, and fluorescence spectroscopy analyses. We identified the purified protein as Bombyx mori lipoprotein 3 (Bmlp3), which has high IgE reactivity and is a novel uncharacterized allergen that we named Bomb m 6 according to the WHO/IUIS Allergen Nomenclature Sub-Committee. This allergen is stable against heat, acids, bases, and digestion. In conclusion, we successfully purified and characterized a novel silkworm pupa allergen, which may inform the diagnosis and treatment of silkworm pupa allergies.

Advanced Proteomic and Bioinformatic Tools for Predictive Analysis of Allergens in Novel Foods

In recent years, novel food is becoming an emerging trend increasingly more demanding in developed countries. Food proteins from vegetables (pulses, legumes, cereals), fungi, bacteria and insects are being researched to introduce them in meat alternatives, beverages, baked products and others. One of the most complex challenges for introducing novel foods on the market is to ensure food safety. New alimentary scenarios drive the detection of novel allergens that need to be identified and quantified with the aim of appropriate labelling. Allergenic reactions are mostly caused by proteins of great abundance in foods, most frequently of small molecular mass, glycosylated, water-soluble and with high stability to proteolysis. The most relevant plant and animal food allergens, such as lipid transfer proteins, profilins, seed storage proteins, lactoglobulins, caseins, tropomyosins and parvalbumins from fruits, vegetables, nuts, milk, eggs, shellfish and fish, have been investigated. New methods for massive screening in search of potential allergens must be developed, particularly concerning protein databases and other online tools. Moreover, several bioinformatic tools based on sequence alignment, motif identification or 3-D structure predictions should be implemented as well. Finally, targeted proteomics will become a powerful technology for the quantification of these hazardous proteins. The ultimate objective is to build an effective and resilient surveillance network with this cutting-edge technology.

Potential of Insect Life Stages as Functional Ingredients for Improved Nutrition and Health

This study aimed to provide information on the nutrients of the edible larval stage of Gonimbrasia cocaulti (GC) for the first time, while exploring the potential nutrient content of the pupal life stages of the domestic silkworm (Bombyx mori; BM) and the Eri silkworm (Samia Cynthia ricini; SC). The three insects were analyzed for fatty acids, minerals, proximate composition and vitamins. Among the fatty acids, linoleic, a polyunsaturated fatty acid, was approximately threefold higher in GC than in the silkworms. The Ca, Fe and K contents were highest in GC. However, the Zn and Na contents were highest in BM, while Mg content was predominant in SC. The crude protein content of the various developmental life stages of the edible caterpillars and pupae ranged between 50 and 62%. Further, the fiber content of GC was substantially higher compared to the pupal stages of the two silkworm species. The vitamin (B₆, B₉, B₁₂ and α-tocopherol) levels of the two insect life stages were considerably high. These insects are comparably rich in nutrients with potential suitability to be utilized in food fortification and thus ease pressure on the over-reliance on animal and plant-based sources, which are becoming unsustainable.

Nutritional aspects and dietary benefits of "Silkworms": Current scenario and future outlook

In the current scenario, it is estimated that by 2050, there will be an additional 2.5 billion people and a 70% increase in food demand. Crop yields are not increasing fast enough to support global needs, and world agriculture is facing several serious challenges. Therefore, insects can be a nutritious alternative to meet the ever-increasing food demand in the present and future. The majority of insect consumption occurs in developing countries, with approximately 1,900 insect species consumed worldwide. Food and feed derived from them are of high quality, have a high feed conversion ratio and emit a low level of greenhouse gases. Among insects silkworms are beneficial to humans, not only because of their high nutritional value, but also because of their several pharmacological properties. Silkworm eggs, larvae, and pupae contains high amount of proteins, oils, minerals, vitamins, and several other beneficial components which are nutritious as well as have positive effect on human health. Studies have shown that silkworm pupae protect the liver, enhance immunity, inhibit apoptosis, inhibit cancer, inhibit tumor growth, inhibit microbial growth, regulate blood glucose and blood lipids, and lower blood pressure. This review paper summerized the nutritional value of different life stages of silkworm, nutritional comparison of silkworm with the major human foods, and the effects of silkworm consumption on human health, thus ittargets to generate interest toward in sericulture and improve human health by using silkworm as a nutritious food and attain sustainability in food and nutritional security.

Silkworm Pupae: A Functional Food with Health Benefits for Humans

Silkworm pupae are insects that are beneficial to human health, not only for their high nutritional value but, more importantly, for the variety of pharmacological functions they can perform when consumed. Currently, there is a lot of interest in the pharmaceutical applications of silkworm pupae. In recent years, the biological functions of domestic silkworm pupae have gradually been identified and confirmed, especially for their beneficial effects on human health. Studies have found that silkworm pupae have positive effects on liver protection, immune enhancement, antiapoptosis, antitumour, antibacterial, regulation of blood glucose and blood lipids, and lowering of blood pressure. However, the pharmacological mechanisms and systemic safety of silkworm pupae have not been systematically evaluated. In this paper, the nutritional composition of the pupae of the domestic silkworm is first summarised. The pharmacological functions of silkworm pupae and their components are then classified, and their mechanisms of occurrence are described. In addition, we provide a preliminary evaluation of the safety of silkworm pupae, analyse their application prospects, and suggest future directions for further pharmacological function studies. The aim is to generate interest in the promotion of human health through the use of silkworm pupae.