Philosamia Ricini Research Articles

Effect of Ultrasonic-Assisted Enzymatic Hydrolysis on Functional Properties and Antioxidant Activity of Eri Silkworm Pupa Protein Isolate

Philosamia ricini (Eri silkworm) pupa protein isolate (EPI) was utilized to prepare pupa protein hydrolysate (EPIH) through enzymatic hydrolysis. Additionally, the isolate underwent ultrasonic treatment at 20 kHz to become ultrasound pretreated EPI (EPIU), which was then enzymatically hydrolyzed to obtain ultrasound pretreated protein hydrolysate (EPIUH). The physicochemical properties of these samples were investigated, including molecular weight, solubility, foaming and emulsion properties, water- and oil-holding capacity, antioxidant activity, and color. When compared to EPI (used as the control), EPIU exhibited a high degree of hydrolysis at 20 minutes ( DH = 29.24 % ). At a total process time of 20 minutes, the degree of hydrolysis for EPIH, EPIU, and EPIUH was found to be 13%, 29%, and 41%, respectively. SDS-PAGE analysis indicated no difference in molecular weight between EPI and EPIU (11–75 kDa). However, the molecular weight profiles of EPIH and EPIUH were reduced (8–45 kDa), resulting in changes in protein functionalities. The high DH value contributed to the enhancement of antioxidant activity, solubility, emulsion capacity, emulsion stability, and foam capacity of the protein isolate at pH 7. Furthermore, the ultrasonic pretreatment of the protein hydrolysate increased the lightness of the protein powder by reducing the enzyme activity of the polyphenol oxidase (PPO). These results suggest that ultrasonic pretreatment of the protein hydrolysate could be applied to improve the properties of Eri silkworm pupa protein for use in the food and beverage industry, such as protein-rich beverages or salad dressings.

Analysis of the Effects of Magnetic Field on the Haemogram Profile and Protein Content of Eri Silkworm, <i>Philosamia ricini</i>

The geomagnetic field is a naturally occurring physical force that operates to sustain life on earth. However, recent advances in technology, rapid urbanization and electromagnetic pollution have led to interferences in strength of the magnetic field, which has resulted in various health hazards in several life forms. This study was carried out to understand the effect of magnetic fields that are greater than the strength of the natural geomagnetic field in Philosamia ricini, commonly known as Eri silkworm. Qualitative and quantitative analysis of the haemogram profile as well as the total protein content, were considered for analysis. The 5th instar silkworm larvae were exposed to two magnetic fields of different strengths, namely 0.4493G and 0.8345G, and changes were recorded and compared with a control group. The results revealed decrease in the number of haemocytes and disruption of haemocytes that increased with increase in strength of magnetic field along. The total protein content of haemolymph also underwent changes with changes in the strength of the magnetic field. Such studies and future in-depth analysis of different biological parameters in organisms due to the changing geomagnetic field might be beneficial in understanding and maneuvering the effects of magnetic field on organisms.

In Vitro Profiling of the Extracellular Matrix and Integrins Expressed by Human Corneal Endothelial Cells Cultured on Silk Fibroin-Based Matrices.

Developing a scaffold for culturing human corneal endothelial (HCE) cells is crucial as an alternative cell therapeutic approach to bridge the growing gap between the demand and availability of healthy donor corneas for transplantation. Silk films are promising substrates for the culture of these cells; however, their tensile strength is several-fold greater than the native basement membrane which can possibly influence the dynamics of cell-matrix interaction and the extracellular matrix (ECM) secreted by the cells in long-term culture. In our current study, we assessed the secretion of ECM and the expression of integrins by the HCE cells on Philosamia ricini (PR) and Antheraea assamensis (AA) silk films and fibronectin-collagen (FNC)-coated plastic dishes to understand the cell-ECM interaction in long-term culture. The expression of ECM proteins (collagens 1, 4, 8, and 12, laminin, and fibronectin) on silk was comparable to that on the native tissue. The thicknesses of collagen 8 and laminin at 30 days on both PR (4.78 ± 0.55 and 5.53 ± 0.51 μm, respectively) and AA (4.66 ± 0.72 and 5.71 ± 0.61 μm, respectively) were comparable with those of the native tissue (4.4 ± 0.63 and 5.28 ± 0.72 μm, respectively). The integrin expression by the cells on the silk films was also comparable to that on the native tissue, except for α3 whose fluorescence intensity was significantly higher on PR (p ≤ 0.01) and AA (p ≤ 0.001), compared to that on the native tissue. This study shows that the higher tensile strength of the silk films does not alter the ECM secretion or cell phenotype in long-term culture, confirming the suitability of using this material for engineering the HCE cells for transplantation.

REARING PERFORMANCE OF ERI SILKWORM (PHILOSAMIA RICINI) FROM WARANA HILLY REGION AREA, KOLHAPUR, MAHARASHTRA

An attempt was made to rear the eri silkworm, Philosamia ricini on the leaves of caster and reared under laboratory condition. It was observed that the caster is a primary potential host of eri silkworm. The growth parameters and cocoon characters of the eri silkworm reared on caster leaves were normal. The eri silkworm successfully lasted its life cycle ranged from 38 to 40 days. The effective rate of rearing, weight of pre-spinning larvae, cocoon, shell and pupae ranged from 70 to 75 per cent, 6 to 7 g, 3.01 to 3.05 g, 0.40 to 0.45g, 2.50 to 2.70g, respectively. Parameters such as length of cocoon shell, width of shell, shell thickness etc. The fecundity ranged from 400 to 425 eggs. Rearing performance of eri silkworm is a need in western Maharashtra for a future development of raw silk production.

Growth Attributes of Eco Races of Eri Silkworm, Philosamia Ricini Donovan in the Western Zone Conditions of Tamil Nadu

One of the most economic exploitation, widely cultivated, and financially viable non-mulberry silkworms is the eri silkworm (Philosamia ricini). The feeds that eri silkworms consume have a significant impact on their yield and silk production. A study was conducted to assess the growth characteristics of the eco races of the eri silkworm in the circumstances of western region of Tamil Nadu. The Central Muga and Eri Research Institute in Jorhat, Assam provided the eco races of eri silkworm. Three replications of the Completely Randomized Design (CRD) were used to set up the treatments. By feeding worms with castor leaves in the cellular rearing method, the growth characteristics of eco races of eri silkworm, specifically the larval parameter and cocoon parameter, were examined. Among the eco races of eri silkworm in comparison with standard F1 hybrid, the eco race Jonai recorded the maximum growth attributes such as larval weight (7.09 g), cocoon weight (3.93 g), shell weight (0.66 g), shell ratio, ERR (16.78 %) which was on par with F1 hybrid followed by Khanapara and Titabar. The least was observed in Barpathar and Adogiri. This study reveals that among ten eco races of eri silkworm, the eco race Jonai recorded performed well in western zone condition of Tamil Nadu and it can be commercially reared in alternative to Commercial F1 breed.

Impact of Starvation on Worms and ionic composition of Haemolymph of Philosamia Ricini

Impact of Starvation on Worms and ionic composition of Haemolymph of Philosamia Ricini

Nutritional Composition of Castor Genotypes and its Influence On Growth Attributes of Eri Silkworm (Philosamia ricini)

Eri silkworm (Philosamia ricini) is one of the most exploited, domesticated, and commercialized Vanya silkworms. Eri silk yield and productivity depend heavily on the feeds ingested by Eri silkworms, which will vary depending on the feed sources. A study was undertaken to evaluate different castor genotypes viz., GCH 4, GCH 7, DCH 519, TMV 5, along with local variety for the nutritional composition and its influence on the growth and economic attributes of Eri silkworm. The treatments were laid out in a Completely Randomized Design (CRD) with three replications. The performance of eri silkworm viz., growth attributes, and economic parameters were studied by feeding them with the leaves of five castor genotypes separately in the tray rearing method. The genotypes showed significant differences in growth and economic parameters of eri silkworm. Among the various genotypes, GCH 4 genotypes showed superior among all the other genotypes on nutritional composition, growth attributes, and economic parameters, followed by genotype DCH 519.

Sericin from mulberry and non-mulberry silk using chemical-free degumming

In this study we report the extraction and characterization of sericin using water alone, from two non-mulberry silks - Antheraea assamensis (A. assamensis) and Philosamia ricini (P. ricini) compared with Bombyx mori (B. mori) silk. Degumming at 130 °C offered the highest sericin removal for A. assamensis; P. ricini had the lowest sericin removal among the varieties, because of its lower overall sericin content. Along with sericin degumming, fiber tensile properties were also reported. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of sericin revealed minimal sericin degradation even for degumming temperatures above 100 °C. The spectra from Fourier Transform Infrared Spectroscopy (FTIR) confirmed random coil motifs for B. mori sericin but a higher proportion of β-sheets in A. assamensis and P. ricini sericin which is likely to contribute to their lower water solubility. Thus, high temperature, water-based processing can be a potential approach for chemical- free degumming of silk fibers and to obtain high molecular weight sericin for different biomaterial applications.

Different photoperiodic effect on moth parameter of Eri silkworm (Philosamia ricini) L. (Saturniidae: Lepidoptera)

Current study represents the different photoperiodic effect on the moth parameter of Eri Silkworm (Philosamia ricini). During the course of study it was observed that maximum emergence of the moth was obtained in 08 hr light and 16hr darkness which is appropriate photo period in comparison to control (normal light and dark). In the present experiment it was observed that the male moths emerged earlier than the female moth.

Estimation of Protein of Silk gland of Philosamia ricini reared in two food plants Ricinus communis and Heteropanax fragrans in two seasons

Estimation of Protein of Silk gland of Philosamia ricini reared in two food plants Ricinus communis and Heteropanax fragrans in two seasons

Performance of Ooencyrtus kuvanae (Hymenoptera: Encyrtidae) on two host species, Halyomorpha halys and Philosamia ricini

AbstractThe brown marmorated stink bug, Halyomorpha halys, is an invasive agricultural pest of fruit trees and vegetables. Egg parasitoids play a key role in the reducing of H. halys populations. Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyrtidae) can parasitize H. halys and complete its life cycle in this host species. Many factors can influence this parasitoid–host relationship. Of these factors, we evaluated the effect of female age, exposure time, and host species on the biological characteristics and fecundity of O. kuvanae reared on eggs of H. halys as well as another previously known host Philosamia ricini (Lepidoptera: Saturniidae). In this study, we used a 3‐year‐old laboratory colony of O. kuvanae. Parasitism rates positively affected by exposure time in P. ricini. The highest parasitism rates were obtained in 5‐ and 7‐day‐old females of both hosts. The highest emergence rates were recorded on P. ricini for 5‐ and 7‐day‐old female P. ricini (81.8% and 84.8%, respectively). The development time of O. kuvanae ranged from 18.4 to 19.1 days on H. halys and 17.7 to 18.3 days on P. ricini. The longevity of O. kuvanae that were provided honey was 38.5 and 47.8 days on H. halys and P. ricini, respectively. The longevity of O. kuvanae that were not provided honey was 2.3 and 2.8 days on H. halys and P. ricini, respectively. The sex ratio was male‐biased (36.5% female) on H. halys and female‐biased (55.2% female) on P. ricini. Fecundity of O. kuvanae was 37.7 and 59.6 progeny per female for H. halys and P. ricini, respectively. The performance of O. kuvanae was lower when compared with its performance on the host P. ricini. Our results suggest that O. kuvanae has potential as new biological control agent for H. halys.

Investigations on the Biodiversity of Tropical Tasar silk moth (Antheraea Mylitta) in Uttar Pradesh

The Non-mulberry silk sector involves tropical and temperate Tasar silk. India is home to five types silk mulberry and non-mulberry silks viz. the tropical Tasar (Antheraea mylitta Drury), and temperate Tasar (Antheraea proyeli J), Muga (Antheraea assamensis Ww.) and Eri (Philosamia ricini Hutt.), All the five silks are produced by silk moths belong to family Saturniidae (order Lepidoptera). Tasar silkworms have stalled itself in several forms of environmental populations normally called as (ecoraces) in various geographical places of the country according to host plants and micro- environmental circumstances. In India Tasar species exists in the form of about 44 ecoraces. The present study, revealed that the diversity of profitable populations of Antheraea mylitta Drury in selected sites of Uttar Pradesh is dependent upon climatic conditions, physical geographics, and their cocoon characteristics vary accordingly.

In Vitro Culture of Human Corneal Endothelium on Non-Mulberry Silk Fibroin Films for Tissue Regeneration.

PurposeThe purpose of this study was to determine if non-mulberry varieties of silk are suitable for the culture of corneal endothelium (CE).MethodsAqueous silk fibroin derived from Philosamia ricini (PR), Antheraea assamensis (AA), and Bombyx mori (BM) were cast as approximately 15 µm films with and without pores on which human CE cells were cultured. Tensile strength, elasticity, transmittance in visible range, and degradation properties of the films were characterised. Adhesion of CE to the silk films was quantified using MTT assay in addition to quantifying the number and area of focal adhesions using paxillin. Expression of CE markers was determined at the gene and protein levels using PCR and immunostaining, respectively. Barrier integrity of the cultured cells was measured as permeability to FITC dextran (10 kDa) in the presence or absence of thrombin.ResultsThe films exhibited robust tensile strength, >95% transmittance and a refractive index comparable to the native cornea. BM degraded significantly faster when compared to PR and AA. A comparison between the three varieties of silk showed that significantly more cells were adhered to PR and AA than to BM. This was also reflected in the expression of stable focal adhesions on PR and AA, thus enabling the formation of intact monolayers of cells on these varieties unlike on BM. Treatment with thrombin significantly increased cellular permeability to dextran.ConclusionsOur data shows that PR and AA varieties sufficiently support the growth and function of CE cells. This could be attributed to the presence of natural cell binding motifs (RGD) in these varieties.Translational RelevanceDevelopment of a suitable carrier for engineering the CE to address a major clinical requirement of healthy donor tissues for transplantation.

The inhibitory effect of silk sericin against ultraviolet-induced melanogenesis and its potential use in cosmeceutics as an anti-hyperpigmentation compound.

Ultraviolet radiation (UVR)-induced redox imbalance in melanocytes triggers the activation of tyrosinase that results in melanogenesis and its related skin disorders. Supplementation of biological reductants or anti-tyrosinase compounds inhibits such melanogenesis. Silk sericin (SS), a globular protein, is known to possess antioxidant and anti-tyrosinase activities along with other biological attributes. However, its inhibitory activity against UVR-induced melanogenesis has yet to be explored. In the current study, we have scientifically explored the inhibitory activity of SS against UVR-induced melanogenesis. Anti-tyrosinase activity of SS was assessed using mushroom tyrosinase, showing that Antheraea assamensis sericin (AAS) and Philosamia ricini sericin (PRS) inhibited 50% of its activity. Inhibitory activity of SS against UVR-induced melanogenesis was assessed by measuring the cellular melanin content, intracellular tyrosinase activity, and reactive oxygen species (ROS) levels in mouse melanoma. SS pretreatment significantly reduced cellular melanin and ROS production in UV irradiated melanocytes compared with SS untreated cells. AAS treatment before UVA or UVB irradiation significantly inhibited tyrosinase activity. Rheological studies showed that the skin care formulation prepared by the addition of AAS to the basic formulation minimally affected its flow properties. Altogether, our results validate that AAS efficiently inhibited UVR-induced melanogenesis and it could be used as a potential antioxidant molecule in skin care cosmeceutics.

3D Bioprinting Using Cross-Linker-Free Silk-Gelatin Bioink for Cartilage Tissue Engineering.

Cartilage tissue is deprived of intrinsic self-regeneration capability; hence, its damage often progresses to a chronic condition which reduces the quality of life. Toward the fabrication of functional tissue substitutes, three-dimensional (3D) bioprinting has progressed vastly over the last few decades. However, this progress is challenged by the difficulty in developing suitable bioink materials as most of them require toxic chemical cross-linking. In this study, our goal was to develop a cross-linker-free bioink with optimal rheology for polymer extrusion, aqueous, and nontoxic processing and offers structural support for cartilage regeneration. Toward this, we use the self-gelling ability of silk fibroin blends (Bombyx mori and Philosamia ricini) along with gelatin as a bulking agent. Silk and gelatin interact with each other through entanglement and physical cross-linking. The ink was rheologically and structurally optimized for printing efficiency in printing grid-like structures. The printed 3D constructs show optimal swelling capability, degradability, and compressive strength. Further, the construct supports the growth and proliferation of encapsulated chondrocytes and formation of the cartilaginous extracellular matrix as indicated by the increased sulfated glycosaminoglycan and collagen contents. This was further corroborated by the upregulation of chondrogenic gene expression with minimal hypertrophy of chondrocytes. Additionally, the construct demonstrates in vitro and in vivo biocompatibility. Notably, the ink demonstrates good print fidelity for printing anatomical structures such as the human ear enabled by optimized extrudability at adequate resolution. Altogether, the results indicate that the developed cross-linker-free silk-gelatin polymer-based bioink demonstrated high potential for its 3D bioprintability and application in cartilage tissue engineering.

Analysis of genetic diversity and phylogeny of Philosamia ricini (Lepidoptera: Saturniidae) by using RAPD and internal transcribed spacer DNA1.

The Indian Eri silkworm, Philosamia ricini Hutt, a commercial silk producing insect, is believed to have originated in the Brahmaputra valley of Assam. In this study, the genetic diversity and phylogenetic relationships of six morphs of Eri silkworm viz. white plain, white zebra, white spotted, blue plain, blue zebra and blue spotted collected from different geographical locations of North-East India were investigated by using random amplified polymorphic DNA (RAPD) and the first internal transcribed spacer region (ITS1). This study revealed a low genetic diversity among the morphs of Eri silkworm. Twenty-eight random primers generated 199 bands. Out of these, 112 were polymorphic (56.28%) with an average of 7.1 bands per primer. The genetic similarity matrix ranged from 0.56 to 0.99. The morphs collected from same geographical area shared the same cluster in the dendrogram. The genetic diversity in case of ITS1 sequences (2.19%) was found to be less as compared to RAPD. The ITS1 sequences of the morphs collected from same geographical area were found to be identical. The information generated in this study will help in conservation and effective breeding program to improve its productivity.

Protective Activity of Silk Sericin against UV Radiation-Induced Skin Damage by Downregulating Oxidative Stress.

Topical delivery ofpotential antioxidants protects the skin against ultraviolet (UV) radiation-induced oxidative damage through maintaining redox balance. Sericin, one of the major components of silk, possesses antioxidant property along with skin-protective activity against UVB radiation-induced damage. However, the protective activity of silk sericin (SS) extracted from different sources has not been explored against UVA and UVB radiation-induced oxidative damage. In the present study, we have systematically investigated the protective activity of sericin against UVA and UVB radiation-induced skin damage. MTT and neutral red assays showed that Philosamia ricini sericin (PRS) and Antheraea assamensis sericin (AAS) (10 μg/mL) treatment prior to UVA (12 J/cm2) and UVB (120 mJ/cm2) irradiations enhanced the viability of human keratinocytes. Examination of cell cycle arrest and apoptotic/necrotic cell death using flow cytometry showed that sericin treatment before UVA and UVB irradiation protected the cells from apoptotic cell death by arresting the cell cycle at G1 phase. Sericin pretreatment downregulated the interleukin (IL)-6 and IL-8, upregulated p53 and decrease the dysregulation of Bcl-2/Bax gene expression. AAS treatment prior to UVB irradiation significantly reduced skin inflammation, DNA fragmentation, and lipid peroxidation in the female SKH-1 hairless mouse skin. Altogether, our results substantiate the use of AAS in effectively ameliorating UVA and UVB radiation-induced skin damage, which holds prospects as a potent antioxidant supplement in the preparation of skin care products.

Silk sericin induced pro-oxidative stress leads to apoptosis in human cancer cells

Pro-oxidative stress induced by dietary polyphenols elevates reactive oxygen species (ROS) production in cancer cells, which subsequently leads to oxidative stress-mediated apoptosis. Sericin, a principal component of silk is associated with a mixture of polyphenols and flavonoids, possesses various biomedical attributes including anticancer activity. In the present study, we have evaluated the pro-oxidative effect of Bombyx mori sericin (BMS), Antheraea assamensis sericin (AAS), and Philosamia ricini sericin (PRS) against different cancer cells. Cytotoxicity of silk sericin (SS) evaluated using A431, SAS, and MCF-7 cells showed ≥50% reduction in their viability at 4 mg/mL. Intracellular ROS levels, cell cycle arrest, and apoptosis assessed using flow cytometry corroborated that SS treatment elevated the intracellular ROS levels, caused cell cycle arrest at the sub-G1 phase and resulted in apoptotic cell death. SS treated A431 and SAS cells showed upregulation of p53 and dysregulation of Bax and Bcl-2 gene expression. Whereas, AAS treated MCF-7 cells showed upregulation of Bax and downregulation of Bcl-2 gene expression. AAS treated MCF-7 and SAS cells showed downregulation of Bcl-2 protein expression in comparison to their control cells. Thus, the present study demonstrates that the pro-oxidative effect induced by SS suppresses the cancer growth indicating its potential anticancer activity.

Modulation of extracellular matrix by annulus fibrosus cells on tailored silk based angle-ply intervertebral disc construct

Reconstruction of native tissue's anatomical and biophysical milieu dictates the success of tissue engineered graft's cellular fate. Herein, we report a facile fabrication procedure to replicate the anatomical and biomechanical features of annulus fibrosus (AF) tissue. A seamless, full thickness disc-like angle-ply construct was fabricated using silk fibroin (SF) protein. To mimic the gradual transition of mechanical gradient from inner to outer region of native AF tissue, SF proteins from two different sources (namely Bombyx mori, BM SF as mulberry, and Antheraea assamensis, AA SF and Philosamia ricini, PR SF as non-mulberry) were blended that provided differential mechanical and cell binding properties. Fabricated constructs were physicochemically and biologically characterized. The seeded porcine AF cells were found to proliferate and align along the lamellar pores as visualized through staining. Gene expression study concluded higher expression of collagen-I with enhancement of mechanical properties, whereas an opposite trend was observed for both collagen-II and aggrecan. Overall, the angle-ply construct with tailored mechanical properties supported cellular alignment and proliferation, and modulated the extracellular matrix (ECM) deposition forming a functional AF tissue like construct, thus providing a robust foundation as an alternative tissue engineered strategy in intervertebral disc (IVD) regeneration for future replacement therapy.

Effect of different photoperiods on the longevity of male and female Moth of Eri silkworm (Philosamia ricini) L. (Saturniidae: Lepidoptera)

The effect of different photoperiods on longevity of male and female of Eri silkworm (P.ricini) was carried in P.G. Madhav Vigyan Mahavidhyalay, Ujjain (MP). The Eri silkworms reared under the exposure of different experimental photoperiods G1 (12L:12D),G2 (LL), G3 (10L:14D), G4 (08L;16D), G5 (05L:19D) and G6 (DD), at temperature (25±2oC) and relative humidity (75±5%).The longevity of male and female moths were maximum in G3 and minimum in G2, complete light.