Degumming Research Articles

GC-MS-based metabonomic analysis of silkworm haemolymph reveals four-stage metabolic responses to nucleopolyhedrovirus infection.

Silkworm, Bombyx mori, an economically significant insect, plays a crucial role in silk production. However, silkworm breeding is highly susceptible to various pathogens, particularly the Bombyx mori nucleopolyhedrovirus (BmNPV), which poses a serious threat. Recent metabonomic studies have provided insights into the metabolic changes associated with BmNPV infection. BmNPV infection has obvious temporal characteristics. However, few studies have investigated the silkworms infected in different periods. This study employed gas chromatography-mass spectrometry (GC-MS) to perform a comprehensive analysis of haemolymph metabolites in silkworms at 48, 72, 96 and 120 h post-infection (h.p.i.). Through the integration of time-course analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, the study revealed distinct four-stage metabolic characteristics in the silkworm's response to BmNPV infection. At Stage 1 (48 h.p.i.), silkworms activate antioxidant defence mechanisms, with significant enrichment in metabolic pathways involving key antioxidants such as glutathione, to mitigate oxidative stress induced by viral invasion. By Stage 2 (72 h.p.i.), pathways related to amino acid metabolism and protein synthesis become active, indicating an increase in protein synthesis. In Stage 3 (96 h.p.i.), energy metabolism and substance transport pathways are significantly upregulated to support the rapid viral replication and the enhanced locomotor behaviour of silkworm. Finally, at Stage 4 (120 h.p.i.), there is a further enhancement of pathways related to energy metabolism, nucleic acid synthesis, and substance transport, which align with peak viral assembly and release. These findings contribute to an in-depth understanding of the biochemical basis of silkworm resistance to NPV.

Effects of different rearing methods on cocoon silk strength in silkworm Bombyx mori (Lepidoptera: Bombycidae).

In recent years, the use of artificial diet to rear silkworm Bombyx mori (L.) (Lepidoptera: Bombycidae) has advanced rapidly in China. However, significant differences are found in the production and performance of silk from silkworms reared on artificial diet and mulberry leaves, thereby affecting the development of artificial diet usage in sericulture. To understand the reasons for these differences, we tested the following 3 rearing methods: all-instar mulberry leaf rearing (Mul), all-instar artificial diet rearing (Diet), and instars 1-3 reared on artificial diet followed by instars 4-5 reared on mulberry leaf (Mix). The results showed that the silk production was significantly lower under Diet than Mix and Mul. Electron microscopy images revealed that the protein synthesis and energy supply were decreased under Dier and Mix compared with Mul. Subsequent strength analysis indicated that the relative strength of silk was highest under Mix, followed by Mul, and weakest under Diet. However, no significant differences in elongation were observed among treatments. The β-sheet content of silk was significantly higher under Mix than Diet and Mul, and a similar trend was observed for the crystallinity. Furthermore, the elevated expression of BmChiNAG and the reduced expression of BmTpn genes may be a significant factor for the notable disparities in cocoon silk fineness and strength among the threes. These findings provide deep insights into the differences in silk produced by silkworms reared on mulberry leaves and artificial diet, as well as providing a reference for improving artificial diet for rearing silkworms.

Identification and functional study of Fib-L, a major silk fibroin gene component in rice leaf folders.

The rice leaf folder, Cnaphalocrocis medinalis (Lepidoptera: Pyralidae), is a major migratory pest in rice agriculture. This pest is characterised by its larvae's ability to fold rice leaves using silk, a behaviour that culminates in the formation of a silken cocoon during the pupal stage. The fibroin light chain (CmFib-L) gene is crucial for silk production, yet its specific function in C. medinalis has reminded elusive. This study presents a comprehensive analysis of the CmFib-L gene, revealing its complete open reading frame (ORF) and expression patterns. Notably, the gene is highly expressed in the fifth-instar larvae and the silk gland, which are critical stages for silk production. Our experiments demonstrate that silencing the CmFib-L gene leads to a reduction in pupal weight, an extension of the pupal stage and a disorganised silk cocoon. Furthermore, the larval behaviour of leaf folding and spinning is significantly impaired when the expression of CmFib-L is downregulated. These findings not only show the importance of fibroin light chain in silk production but also reveal a new target gene to regulate and control the behaviour and development of C. medinalis.

Influence of Natural Dyes on the Qualitative and Quantitative Parameters of Bivoltine Silkworm Breeds under Sub-Tropical Conditions of Poonch District, Jammu and Kashmir

The study on Influence of Natural Dyes on the qualitative and quantitative parameters of Bivoltine Silkworm Breeds under Sub-tropical Conditions of Poonch District, UT Jammu and Kashmir,” was conducted during the spring of 2022 at the PG, Department of Sericulture, Poonch Campus, University of Jammu. The study examined the effects of feeding bivoltine silkworm breeds CSR16 and CSR27 with two concentrations (50% and 100%) of natural dyes: madder (Rubia cardifolia) and indigo blue (Indigofera tinctoria). A comprehensive evaluation of both qualitative and quantitative parameters was undertaken, including fecundity, hatching %, larval duration, weight of 10 mature larvae, survival rate, mortality %, pupation % and cocoon quality parameters. The results indicated significant enhancements in fecundity, hatching % and cocoon yield for silkworms treated with both dyes at 100% concentration (T2). Specifically, CSR16 and CSR27 exhibited the highest values for larval weight, cocoon weight, pupation rate and shell ratio % in T2 treatments. The findings suggest that feeding silkworms natural dyes, particularly at higher concentrations, significantly improved the economic parameters of both breeds. While the cocoons produced were intrinsically coloured without compromising commercial parameters, the colour intensity was lighter than anticipated. This implies that introducing dyed mulberry leaves during the 1st instar stage may yield more favourable results. Overall, the study demonstrates that madder and indigo dyes are suitable for producing coloured silk, offering potential for large-scale applications in sustainable silk production.

Three Novel Spider Genomes Unveil Spidroin Diversification and Hox Cluster Architecture: Ryuthela nishihirai (Liphistiidae), Uloborus plumipes (Uloboridae) and Cheiracanthium punctorium (Cheiracanthiidae).

Spiders are a hyperdiverse taxon and among the most abundant predators in nearly all terrestrial habitats. Their success is often attributed to key developments in their evolution such as silk and venom production and major apomorphies such as a whole-genome duplication. Resolving deep relationships within the spider tree of life has been historically challenging, making it difficult to measure the relative importance of these novelties for spider evolution. Whole-genome data offer an essential resource in these efforts, but also for functional genomic studies. Here, we present de novo assemblies for three spider species: Ryuthela nishihirai (Liphistiidae), a representative of the ancient Mesothelae, the suborder that is sister to all other extant spiders; Uloborus plumipes (Uloboridae), a cribellate orbweaver whose phylogenetic placement is especially challenging; and Cheiracanthium punctorium (Cheiracanthiidae), which represents only the second family to be sequenced in the hyperdiverse Dionycha clade. These genomes fill critical gaps in the spider tree of life. Using these novel genomes along with 25 previously published ones, we examine the evolutionary history of spidroin gene and structural hox cluster diversity. Our assemblies provide critical genomic resources to facilitate deeper investigations into spider evolution. The near chromosome-level genome of the 'living fossil' R. nishihirai represents an especially important step forward, offering new insights into the origins of spider traits.

Performance Evaluation of a Mechanically-aided Cocoon Deflosser

Sericulture products such as woven linen and novelty items were already sold at the market at premium-priced commodities. However, it was not given emphasis and sustainable support. One of the problems identified is the availability of cocoon silk production machinery and equipment. Humans can defloss 2 to 3 kg or 900 to 1,600 pieces of cocoon in an hour. Therefore, cocoon delfossing is a tiresome laborious job. This contributes to the market's poor production of silk and novelty items. Hence, a cocoon deflossing machine with a higher deflossing capacity than a manual is needed. To address this concern, a mechanically aided cocoon deflossing machine was designed, fabricated, and evaluated. Performance evaluation of the machine shows that it lessens deflossing cost from USD 0.53 /kg manual deflossing to USD 0.47/kg. It has a capacity of 4.80 kg/hr and 2,374 pieces of cocoons per hour.

Review on Silk Worm Pupal Meal: A Protein Source in Aquatic Animal Nutrition as a Replacement of Fish Meal

Amongst the insect meals, silkworm pupal meal is the most efficient fish meal replacement. It can be utilized in aquatic animal feeds as pupal meal, deoiled silkworm pupal meal and fermented pupal meal, to increase growth performance. It also has a significant impact on animal body composition and digestive enzyme activity. India is the world's second-largest producer of silk, and a vast amount of silkworm pupae waste is discharged into the environment, which can be used as protein in feed. It has a strong nutritional profile that is near or equal to fish meal, consists of 50-80% of crude protein on dry matter, rich in important amino acid profile, (methionine 3.5, lysine 7.0, aspartic acid 10.4, threonine 5.2, serine 5.0, glutamic acid 13.9, proline 5.2, glycine 4.8, alanine 5.8, cystine 1.0, valine 5.5, isoleucine 5.1, leucine 7.5, tyrosine 5.9, phenylalanine 5.1, histidine 2.6, and arginine 5.6) and lipid content ranges from 20-40% in freshly spent pupa and less than 10% in defatted pupa. The oil derived from pupa is high in alpha-linolenic acid, oleic acid, palmitic acid and the gross energy values range from 5.09 to 6.28 MJ/kg. It also contains interesting minerals and vitamins, which piqued the interest of researchers in its use in aqua feed. Aside from the nutritional profile, nutrient digestibility, and the effect of diet on organoleptic quality revealed that SWP meal is equivalent to fish meal in all respects. So, the current review focuses on the effects of silkworm pupal meal on aquatic animals when supplied through diets.

Participating in the Production of Silk Handicrafts in Phonxay Village, Luangprabang City

This study aim to study the participation in the production of silk handicrafts in Phon Xai Village, Luangprabang District, as a quantitative research which used questionnaires to collect data from a sample group of 98 people and analyze the data with the statistical program SPSS version 20. The results of the study found that people are most involved in the production and service of silk products, participation in marketing, participation in skills in silk production, and participation in administration and management Production of silk with the average total value is between 0.36-0.42 and the standard deviation is between 0.10-0.65. People are involved in the medium level of participation in the use of information technology and participation in the use of internal potential in production and services, with an average

Impact of leaves of different mulberry genotypes on nutritional efficiency of conversion parameters of silkworm, Bombyx mori L.

The silkworm, Bombyx mori, is a domesticated insect widely used to produce silk worldwide for human consumption. B. mori is a monophagous insect that feeds on nutritious mulberry leaves to produce silk. The efficiency of conversion of leaves to larval biomass by silkworm larva largely depends upon the type of silkworm breed/hybrid and the quality of mulberry leaves fed to them. The silkworms having good efficiency of conversion of leaves perform better in larval growth and silk gland development, which finally leads to enhanced silk production. In the current research work, the highest efficiency of conversion of ingesta to larva (28.608%) and efficiency of conversion of digesta to larva (51.527%) were found in Goshoerami fed silkworm batch which differed significantly from other varieties.

Challenges and Adoption of Bivoltine Hybrid Silkworm Rearing in Karnataka's South-Eastern Dry Zone, India

The present study explores the adoption of bivoltine hybrid silkworm rearing practices in the South-Eastern Dry Zone of Karnataka, specifically within the Kolar and Chikkaballapur districts. Data collected from thirty sericulturists using a pretested interview schedule, reveal a mixed picture of practice adoption. The adoption levels of recommended practices vary significantly among rearers. While high adoption rates were observed for certain practices, such as the use of recommended mulberry varieties and irrigation techniques, other practices show only moderate adherence. Specifically, cent per cent of the sericulturists have adopted the recommended mulberry variety and 93.33% follow suggested irrigation schedules. However, there is only a 60% adoption rate for the use of prescribed fertilizers and pest management practices. The study also highlights several key constraints impacting the adoption of these practices. Major constraints include limited access to quality inputs, insufficient technical knowledge and inadequate extension services. Financial constraints and environmental challenges further exacerbate these issues, affecting the overall effectiveness of sericulture practices. Recommendations to improve adoption levels include enhancing access to quality inputs, enhancing educational and extension services which talking financial obstacles. By implementing these recommendations, it is anticipated that sericulturists in these region will be better equipped to adopt and benefit from advanced silkworm rearing practices, resulting in greater productivity and long-term sustainability in the sericulture sector.

Impact of Methionine and Tryptophan Supplementation on Silk Gland Weight and Tissue Somatic Index in Eri Silkworm (Samia ricini Donovan)

This study evaluated the impact of methionine and tryptophan supplementation on the silk gland weight and Silk Gland Tissue Somatic Index (SGTSI) of eri silkworm, Samia ricini Donovan, a key species in vanya silk production. Freshly collected castor leaves were fortified with methionine and tryptophan solutions at various concentrations and fed to silkworm larvae from the third instar until maturity. The treatments significantly enhanced silk gland weight and SGTSI compared to the control. The highest silk gland weight (1.52g) and SGTSI (25.16%) were observed in larvae fed with tryptophan at 500 ppm (T6), followed by methionine at 500 ppm (T3) with 1.47g and 24.61%, respectively. Control larvae exhibited the lowest values (1.07g and 19.43%). Combination treatments of methionine and tryptophan showed less improvement compared to individual treatments. These findings suggest that dietary supplementation with specific amino acids could enhance silk gland development and silk production.

Exploring the relationship between raw silk production and employment growth in the Indian sericulture Sector

Exploring the relationship between raw silk production and employment growth in the Indian sericulture Sector

Innovations in Sericulture an Advancements in Silk Production and Quality Improvement

Sericulture, the cultivation of silkworms for silk production, has a long and significant history, particularly in rural economies. In recent years, the industry has undergone transformative innovations that have enhanced efficiency, sustainability, and silk quality. This review explores key advancements in sericulture, focusing on technological innovations, genetic improvements, sustainable farming practices, and the role of biotechnology in reshaping the industry. Notable technological developments, such as automated silk reeling machines and climate-controlled rearing houses, have streamlined production, reducing labor demands while ensuring consistent silk quality. Additionally, digital monitoring systems now allow for real-time tracking of silkworm health and environmental conditions, empowering farmers with data-driven insights for better management. Genetic advancements, including selective breeding and genetic engineering, have led to high-yield, disease-resistant silkworm strains, significantly boosting silk output and quality. Moreover, innovations in producing naturally colored silk via genetic modification have minimized the need for chemical dyes, reducing the environmental footprint of the dyeing process. Sustainability has become a focal point, with organic farming methods, integrated pest management (IPM), and waste recycling practices becoming more widespread. These practices not only safeguard the environment but also enhance the economic viability of sericulture, benefiting rural communities and driving social development. Biotechnology has expanded the horizon of sericulture, enabling the engineering of silk proteins and the creation of transgenic silkworms for specialized medical and industrial applications. Overall, these advancements have transformed sericulture into a more efficient, sustainable, and economically viable industry, offering significant benefits to both global silk markets and rural livelihoods.

Potential uses of silkworm pupae (Bombyx mori L.) in food, feed, and other industries: a systematic review.

The increasing pressures imposed on ecosystems by the growing needs of the human population are stimulus for research into innovative and unconventional sources of raw materials for different industries. This systematic review was carried out to investigate the available literature on the possible industrial uses of silkworm (Bombyx mori L.) pupae, a residue of silk production. The review was conducted using an adapted version of PRISMA. After a screening process, 105 articles were obtained and subjected to a detailed quantitative and qualitative analysis. It was found that in the last decade there has been a significant increase in the number of papers devoted to the study of the potential use of silkworm pupae in different applications, with a significantly higher number in the last three years of the scope of this review, indicating a growing interest in the subject. From the analysis of the information collected, promising uses in human and animal food, such as fish, mammalian, poultry, swine and companion animals, as well as potential uses for the pharmaceutical industry, were identified. The evaluated research identified compounds with antioxidant activity and important contents of unsaturated fatty acids, which are related to beneficial effects on cardiovascular health, diabetes control, reduction of the risk of developing certain types of cancer and inflammatory activity, among other benefits. One of the most relevant findings is that many studies report a significant concentration of α-linolenic acid in silkworm pupae oil, which is attributed with anticancer, anti-inflammatory, antioxidant, anti-obesity and neuroprotective properties, among others.

From Ancient Threads to Colonial Commerce: The Evolution of West Bengals Silk Industry from Mythical Origins to Independence

Silk production, or sericulture, has a rich history that is frequently eclipsed by its modern applications. Sericulture began in ancient China approximately 3000 BC and this was a well held secret until it spread to Korea, India and eventually the West through a variety of causes, including royal intrigue and missionary endeavours. By the Han Dynasty, silk had evolved from a luxury item to a valuable economic asset, impacting trade and culture throughout Asia and Europe. India's silk industry, as documented in ancient scriptures, progressed from early wild silk production in the Himalayan foothills to sophisticated mulberry sericulture by the 2nd century BCE. The Mughal dynasty improved Indian silk traditions by incorporating several weaving techniques and nurturing a thriving business in Kashmir and Bengal. From 1612 to 1858, the East India Company capitalised on Bengal's silk potential by building trading centres and using Piedmontese reeling technology to improve quality. Despite initial hurdles, Bengal silk became a major export commodity, but colonial policies and technological shifts eventually led to its demise. Silk output fell dramatically after independence due to a variety of economic and geopolitical issues. This article investigates the growth of India's silk industry, focussing on Bengal's key role and examines the effects of colonial control, technological advancements and the sector's trajectory up to Independence.

Juvenile Hormone Mimics as Biochemical Enhancers for Silk Production in Bombyx mori L.: Evidence from Plant Extracts

Aim: To study the Effect of juvenile hormone mimics on the biochemical parameters of silkworm. Study Design: Factorial Complete Random Design. Place and Duration of Study: Department of Sericulture, Forest College and Research Institute, Mettupalayam during 2021-2022. Methodology: Topical application of 20% and 30% acetone extracts of Juvenile hormone mimics at different interval of larval duration viz. IV and V instar of silkworm as single treatment (on first day of V instar) and double treatment (twice – first day of IV and V instar). Silkworm breed used Double Hybrid (FC1XFC2). Results: Double administration at 20% and 30% concentration for Pinus and Tapioca treated larvae—increases, it is observed that the amount of expression of biochemical traits increases. Significantly higher silk gland protein content of (119.85 mg/g) was recorded in double dose @ 30% Pinus with highest fat body protein of 51.00 mg/g and least was recorded in untreated control. Serimore recorded highest aspartate aminotransferase activity (264.24 µg/ml) followed by Pinus (269.93 µg/ml) whereas 563.22 µg/ml and 558.31 µg/ml alanine aminotransferase activity recorded when treated with pinus and serimore respectively. Conclusion: Among the phutojuvenoids, pinus was best followed by tapioca and then custard apple. Among tapioca series, tapioca plant showed best result followed by tapioca leaf and tapioca branch. In case of custard apple series, custard apple plant was better followed by custard apple branch and least by custard apple leaf. Pine was found to be on par with commercially available JHA serimore.

Impact of Muga Silkworm Culture in Augmenting Rural Income of Assam, India

Mugaculture is traditionally practiced by the rural population of Assam. Rearing of Muga silk worm is done by most of the villagers belonging to various districts of Assam as an additional source of income. Envisaging the prospects of Muga industry in Assam, the present work tries to study the role of Mugaculture to alleviate rural poverty. The present study was carried out in Dhemaji district of Assam during 2020 to 2022. The study focuses to examine the different aspects of Muga culture and its significance for the livelihood of local people. The parameters identified for analysis included the nature of Mugaculture practices in the study area, the contribution of Mugaculture to rural households and the economic prospects of Mugaculture. The present study finds that income from Mugaculture practices contributes significantly to the total income of the people. The Mugaculture practice in the study area is found to be an avocation that people engage in between other farming activities and people use traditional methods of Mugaculture. Income is generated through selling of cocoon, pupae and muga silk threads. Moreover, a cost-benefit ratio analysis conducted indicates that Mugaculture is a profitable venture of the people.

Role of Sericulture in the Indian Economy

Sericulture, often known as silk farming, involves raising silkworms to make silk. Out of the five states that contribute to the majority of India's silk production—Karnataka, Andhra Pradesh, Tamil Nadu, West Bengal, and Jammu & Kashmir -98.5% comes from mulberry sericulture. Silk plays a vital role in Indian culture and tradition, with a rich history spanning over five millennia. Sericulture, especially in Karnataka, supports farmers' livelihoods and has significant economic potential. However, climate change poses a serious threat to global ecosystems, endangering species and affecting industries like sericulture. The Author uses the study variables for their study and also questionnaires, and statistical tools like SPSS and Excel for data presentation and calculation respectively also used statistical techniques like, Factor Analysis, Descriptive analysis, and Relatively Analysis. Sericulture enhances income, crop diversification, sustainability, and land use efficiency, supported by government policies and training. Sericulture is vital to India’s rural development, job creation, and exports. It supports millions of rural households, especially women and marginalized communities, by generating consistent income. As one of the world’s top silk producers, India benefits from government-backed sustainable practices, making sericulture crucial to its economy.

Performance of Recently Developed Single and Double Hybrids of Bivoltine Silkworm (Bombyx mori) in India

India, contributing over 18% to global silk production, has made significant strides in sericulture through advancements in silkworm breeding. This review evaluates the performance of recently developed single and double hybrids of bivoltine silkworms (Bombyx mori) in India. These hybrids are essential for enhancing silk productivity and quality, addressing the challenges of environmental stress. This assessment reveals that these new hybrids exhibit improved growth rates, silk yields, and thermotolerance. However, limitations such as genetic stability and environmental sensitivity persist, which could impact long-term sustainability. The novelty of this work lies in its comprehensive analysis of these hybrids’ performance under varied conditions, providing insights into their potential and areas needing further improvement. Continued research, advanced breeding techniques, integrated pest and disease management, large scale evaluation at farmer’s field and supportive policies are crucial for the sustainable growth of India’s sericulture industry. By adopting these hybrids and modern rearing practices, the industry can achieve higher yields, better quality silk and substantial contributions to the rural economy and global silk market.

The evolution of silk production in Crustacea

ABSTRACT Spun silk is found only in arthropods, where it plays critical roles in feeding, protection, and reproduction. It has evolved repeatedly within the arthropods, providing an opportunity for comparative analyses to reveal the mechanisms driving convergent evolution within this taxon. Silk in crustaceans has received much less attention than silk in arachnids and insects but may have unique and useful properties. We combine data on the morphology of silk and silk systems with ancestral state reconstruction and find that silk has likely evolved convergently at least six times within Crustacea. We also break down the components of crustacean silk as a composite trait by discussing the silk properties, the silk production systems, and the silk genes. We find that amphipod and tanaid silks are similar to silkworm and spider silks but have their own unique silk system morphology. Much remains unknown about the origins and diversification of silk in crustaceans; we propose that the molecular investigation of silk genes and systems will provide a path forward. By investigating the evolution of silk production in crustaceans, we may discover insights into predispositions for silk production in arthropods and valuable substrates for biomaterial research.