• The Plant Pathology Journal
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• v.17 no.6
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• pp.357-360
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• 2001

Gray mold was observed on leaves of castor bean grown in Woniu and Okcheon in Korea in October 2000. Symptoms developed in the form of spot and blight with sporulation of the causal fungi at the marginal or central parts of the leaves. A total of 25 isolates were obtained from the infected leaves of castor bean. Out of the 25 isolates, 5 isolates which originated from Woniu were identified as Botrytis cinerea, while 20 isolates from Okcheon were identified as Amphobotrys ricini based on morphological and cultural characteristics. Two isolates each of B. cinerea and A. ricini were tested for their pathogenicity to castor bean plants. Gray mold symptoms similar to those observed in the fields were induced on leaves of castor bean by artificial inoculation. This is the first report of gray mold in castor bean caused by B. cinerea and A. ricini in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.121-131
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• 2016

Ten microsporidian isolates from Samia cynthia ricini, and Antheraea assamensis in India along with a Nosema reference strain (NIK-1s_mys) from B. mori India were characterised morphologically and molecular based tools. The test isolates observed elongated oval in shape while reference strain was oval and ranging from 3.80 to 4.90 m in length and 2.60 to 3.05 m in width. The ribosomal DNA region 'IGS' of test isolates assessed by PCR amplification, followed by cloning and sequencing. IGS sequence and phylogenetic analysis of test microsporidian isolates showed very close relationship with three Nosema references species: N. philosamia, N. antheraea isolated from Philosamia cynthia ricini and Antheraea perny in China respectively and N. disstriae from Malacosma disstriae in Canada. The clustering pattern of dendogram reveals all test isolates appear distinct from Nosema std. (NIK-1s_mys) India used as reference strain in the study. The result suggests IGS indeed a suitable and highly applicable molecular tool for identifying and characterise the microsporidian isolates in similar population.

• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1367-1378
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• 2020

The polyphagous eri silk moth, Samia ricini, is associated with various symbiotic gut bacteria believed to provide several benefits to the host. The larvae of S. ricini were subjected to isolation of gut bacteria using culture-dependent 16S rRNA generic characterization, metagenomics analysis and qualitative enzymatic assays. Sixty culturable aerobic gut bacterial isolates comprising Firmicutes (54%) and Proteobacteria (46%); and twelve culturable facultative anaerobic bacteria comprising Proteobacteria (92%) and Firmicutes (8%) were identified inhabiting the gut of S. ricini. The results of metagenomics analysis revealed the presence of a diverse community of both culturable and un-culturable gut bacteria belonging to Proteobacteria (60%) and Firmicutes (20%) associated with seven orders. An analysis of the results of culturable isolation indicates that these bacterial isolates inhabited all the three compartments of the gut. Investigation on persistence of bacteria coupled with metagenomics analysis of the fifth instar suggested that bacteria persist in the gut across the different instar stages. In addition, enzymatic assays indicated that 48 and 75% of culturable aerobic, and 75% of anaerobic gut bacterial isolates had cellulolytic, lipolytic and nitrate reductase activities, thus suggesting that they may be involved in food digestion and nutritional provision to the host. These bacterial isolates may be good sources for profiling novel genes and biomolecules for biotechnological application.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.210-216
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• 1995

Partially purified water-soluble extract mixture from Ricini and Coptidis (named as RIC) showed to be a potent inhibitor of human immunodeficiency virus-1 (HIV-1) replication. RIC was evaluated for in vitro anti-HIV activity using SupTl and H9 cells infected by a recombinant virus (pSVCAT) containing chloramphenicol acetyltransferase (CAT) gene substituted for nef gene in the HIV-1 genome. RIC inhibited syncytiaformation of SupTl cells with a half maximal effective concentration, $IC_{50}$/, of 2.5 $\mu\textrm{g}$/mι and showed marked inhibition of CAT activity in the infected H9 cells and also suppressed reverse transcriptase (RT) activity in the supernatant of the infected H9 culture. However, RIC did not inhibit the activity of reverse transcriptase directly when it was mixed with the enzyme or with viral particles. Berberine, one of components of RIC, also showed similar anti-HIV activity as RIC did. The data suggest that there are active ingredients which mediate anti-HIV activity in RIC.

• International Journal of Industrial Entomology and Biomaterials
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• v.28 no.2
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• pp.32-38
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• 2014

Food consumption and conversion efficiency of eri silkworm Samia ricini Donovan were studied during $4^{th}$ and $5^{th}$ larval instars by feeding castor leaves fortified with 100, 200, 300, 400 and 500 ppm concentrations of aqueous extracts of cyanobacteria Anabaena variabilis. The nutritional indices viz., ingesta, digesta, approximate digestibility (%), reference ratio and efficiency parameters like ECI and ECD were recorded which were significantly high at 400 ppm concentration treated batches of $4^{th}$ instar larvae over control batches. The decline in nutritional efficiency parameters of $5^{th}$ instar treated larvae might be due to higher utilization of the digested food for metabolic activities. Significant difference of ECI to cocoon % and non-significant difference of ECD to cocoon% and shell were observed between the treatments and control. Cyanabacteria feed supplement contains antibiotic and nutritions factors which has reflective effect on the biological parameters in eri silkworm and therefore has greater application in commercial eri silkworm rearing.

• Journal of Sericultural and Entomological Science
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• v.33 no.2
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• pp.93-96
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• 1991

The "Manta"(Juvenile hormone analogue-Methoprene) was topically applied at 36.48 and 72 hrs after the fourth ecdysis to eri silkworm, Samia cynthia ricini with doses of 2.75$\mu\textrm{g}$/$m\ell$, 4/0$\mu\textrm{g}$/$m\ell$ and 8.0$\mu\textrm{g}$/$m\ell$. The eri silkworm responded to 2.75$\mu\textrm{g}$/$m\ell$ of "Manta" applied at 72 hrs after the fourth ecdysis, resulting in improvement of larval, cocoon, pupal and cocoon shell weigths.ocoon shell weigths.

• International Journal of Industrial Entomology and Biomaterials
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• v.30 no.1
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• pp.6-16
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• 2015

This study established the genetic characterisation of 10 microsporidian isolates infecting non-mulberry silkworms (Antheraea assamensis and Samia cynthia ricini) collected from biogeographical forest locations in the State of Assam, India, using PCR-based markers assays: inter simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD). A Nosema type species (NIK-1s_mys) was used as control for comparison. The shape of mature microsporidian spores were observed oval to elongated, measuring 3.80 to $4.90{\mu}m$ in length and 2.60 to $3.05{\mu}m$ in width. Fourteen ISSR primers generated reproducible profiles and yielded 178 fragments, of which 175 were polymorphic (98%), while 16 RAPD primers generated reproducible profiles with 198 amplified fragments displaying 95% of polymorphism. Estimation of genetic distance coefficients based on dice coefficients method and clustering with un-weighted pair group method using arithmetic average (UPGMA) analysis was done to unravel the genetic diversity of microsporidians infecting Indian muga and eri silkworm. The similarity coefficients varied from 0.385 to 0.941 in ISSR and 0.083 to 0.938 in RAPD data. UPGMA analysis generated dendrograms with two microsporidian groups, which appear to be different from each other. Based on Euclidean distance matrix method, 2-dimensional distribution also revealed considerable variability among different identified microsporidians. Clustering of these microsporidian isolates was in accordance with their host and biogeographic origin. Both techniques represent a useful and efficient tool for taxonomical grouping as well as for phylogenetic classification of different microsporidians in general and genotyping of these pathogens in particular.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.51-51
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• 2005

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.50-50
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• 2005

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.13-17
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• 2002

Present communication deals with quantitative determination of total lipid, triglycerides, total free fatty acids, phospholipids and total cholesterol in the fat body tissue of the silkworm adapted to low and high temperatures. At the end of spinning process is characterized by a marked cellular reorganization of the different lipid fraction of the fat body irrespective of thermal acclimation. Accordingly, the per cent composition of triglycerides of the total lipid is increased accompanied by a corresponding decrease in free fatty acids, phospholipids and cholesterol.