White僵蚕 (Bai Jiang Can): What are its benefits? What components does it contain? Today we provide a detailed explanation of White僵蚕, hoping it proves helpful.
【Sources】
1. The Divine Farmer's Classic of Materia Medica.
2. The Supplement to the Divine Farmer's Classic of Materia Medica: White stiff silkworms are found in the plains of Yingchuan. Collect them in April from dead silkworms, ensuring they remain dry. Wet ones become toxic and unusable.
3. Tao Hongjing: When silkworms are raised in households, some may stiffen on the bamboo trays. If dried promptly, they remain intact. The best specimens are small and white, appearing slightly salty.
【Pinyin】BáiJiānɡCán
【English Name】Whitesilkworm
【Aliases】Stiff Silkworm, Celestial Worm, Stiff Worm, White Stiff Worm
【Source】
Medicinal origin: Entire larvae of the domestic silkworm moth (Bombyx mori) infected with Beauveria bassiana and stiffened by death.
Latin botanical name: Beauveria bassiana (Bals.) Vaillant.
Harvesting and storage: Historically, stiffened silkworms were collected only from naturally deceased individuals.In recent years, artificial inoculation and cultivation have been employed. Method: After the silkworms undergo their fourth molt, prepare a fungal suspension of Beauveria bassiana using warm or cold water. Apply the suspension evenly to the silkworms using a sprayer until the bodies appear moist. Feed the silkworms mulberry leaves for the 14th time 15-20 minutes after inoculation, then feed them every 5-6 hours thereafter.Maintain rearing room temperature at 24–26°C (75–79°F) with 90% humidity. Avoid ventilation. After inoculation, silkworms progressively develop symptoms and die. Promptly remove them, spread them out separately, and maintain the same temperature. Once fully stiffened and whitened, place them in a ventilated area to air-dry or under weak sunlight to dry.【Original Form】The silkworm moth (Bombyx mori) exhibits dense white scales covering both male and female adults. Body length: 1.6–2.3 cm. Wingspan: 3.9–4.3 cm. Body and wings range from yellowish-white to grayish-white.The outer margin of the forewing is concave-cut posteriorly at the apical angle. The transverse lines are slightly darker but not very distinct. The terminal line and wing veins are grayish-brown. The hindwing is paler than the forewing, with slightly longer scale hairs along the margin. The female abdomen is plump and rounded at the tip; the male abdomen is narrower with a slightly pointed tip.The larvae, known as silkworms, are grayish-white to white in color. The second and third thoracic segments are slightly swollen and wrinkled. The dorsal surface of the eighth abdominal segment bears a tail horn.
【Habitat and Distribution】
Ecological Environment: Cultivated throughout most regions of China.
Resource Distribution: Widely distributed.
【Cultivation】
Inoculate the spores of Beauveria bassiana onto the silkworm's skin. Under suitable temperature and humidity conditions, the spores germinate, invade the silkworm's body, causing it to die and stiffen, thus forming stiffened silkworms.
1. Preparatory Work: 4-6 days prior to inoculation, clean and disinfect silkworm rooms and equipment. Use 2% formalin solution heated to above 24°C, spraying 15ml per square foot, then seal for 24 hours. Alternatively, use a mixture of 0.2% Salix extract and 0.5% or 1% lime slurry, spraying 25ml per square foot.
2. Inoculation: After the fourth dormancy period, before the fifth instar begins feeding, prepare a uniform suspension using僵蚕洗液 (stiff silkworm wash solution) or artificially cultured Beauveria bassiana. Use a single-tube sprayer to evenly spray the suspension onto silkworm bodies until they appear moist.The inoculation rate is critical for producing stiff silkworms. Therefore, the spore concentration should be adjusted based on climatic conditions and reared strain. In Zengcheng, Guangdong, approximately 80,000–100,000 spores per milliliter (ml) of inoculum are used. In Wuxi, Jiangsu, 50,000–60,000 spores per ml is generally optimal.
3. Management: During inoculation, maintain humidity and temperature in the rearing room, keeping the dry bulb temperature within 0-1°C of the wet bulb. An ambient temperature of approximately 25°C is ideal.First mulberry feeding should occur 15-20 minutes after inoculation, followed by subsequent feedings every 5-6 hours to ensure thorough consumption of high-quality mulberry leaves. Temperature and humidity are critical factors affecting stiffening rates. Cooling is necessary during hot weather, and humidity should be supplemented when insufficient. Dead silkworms should be promptly removed and placed in separate nests to maintain optimal temperature and humidity for complete stiffening.【Characteristics】
Characteristic identification: This product is cylindrical, often curved and shrunken, measuring 2-5 cm in length and 0.5-0.7 cm in diameter. The surface is grayish-yellow, covered with white powdery aerial mycelium and conidia. The head is relatively rounded, with 8 pairs of legs and distinct body segments. The tail end is slightly bifurcated.Hard yet brittle, it breaks easily with a flat fracture surface. The outer layer is white and powdery, with a bright brown to dark brown center—commonly called the "glue-mouth mirror"—containing four brightly ringed glandular lines. It has a faint fishy odor and slightly salty taste.
Microscopic identification: Powder characteristics: grayish-brown or grayish-brown.① Hyphae nearly colorless, slender and curled within the body wall, 1-5 μm in diameter, predominantly found in the body wall or pale brown translucent crystalline masses. ② Fragments of tracheal wall slightly curved or isolated, bearing brown or dark brown spiral filaments with 1-3 extremely fine corrugations between them.③ Epidermal tissue surface exhibits reticulate wrinkled texture and small spines formed by textural protrusions, with circular trichome pits and yellow margins; setae are yellow or yellowish-brown, smooth-surfaced, and slightly thick-walled. ④ Most undigested mulberry leaf tissue contains calcium oxalate clusters or stalactites. Additionally, colorless crystalline bodies may be scattered or embedded within the tissue.【Chemical Composition】White僵蚕 contains proteins, ammonium oxalate, and amino acids including lysine, leucine,aspartic acid, and 28 elements including magnesium, calcium, and zinc. It also contains metamorphosis-active hormones, ecdysone, and pigments such as 3-hydroxykynurenine,and 6-N-hydroxyethyladenine. Beauveria bassiana mycelium contains tenellin and bassianin, a pigment that rapidly accumulates when nitrogen sources are depleted during cultivation.It also contains multiple cyclodepsipeptide components: bassianolide, beauverilide A and B, and beauverolide A,B, Ba, C, Ca, D, E, Ea, F, Fa, H, I, Ja, and Ka; fatty acid amide components: palmitamide and stearamide;Piperazine-2,5-dione derivatives: Cyclo(L-Ile-L-Val) dipeptide,Cyclo(L-Ile-L-Ile) dipeptide, Cyclo(L-Ala-Pro) dipeptide;Lipid components, primarily composed of palmitic acid, oleic acid, linoleic acid, and minor amounts of stearic acid and palmitoleic acid.Additionally, Beauveria bassiana secretes at least three hydrolases: lipase, protease, and chitinase, which facilitate penetration through the cuticle of infected larvae. It also synthesizes fibrinolysin and utilizes glutamic acid,aspartic acid, ammonium oxalate, ammonium citrate, and ammonium tartrate as nitrogen sources, but cannot efficiently utilize inorganic nitrogen compounds.In addition to infecting silkworms, Beauveria bassiana also attacks larvae of the corn borer (Pyrausta nubialis) and the wax moth (Galleria mellonella). From these hosts, it produces high-molecular-weight insect toxins and cyclic peptide insect toxins such as beauvericin. It also contains the steroid 11α-hydroxylase enzyme system, which is used to synthesize corticoids.-Hydroxylase System for Corticoid Synthesis.
【Pharmacological Effects】
1. Anticonvulsant Effect: Oral administration of 10% decoction at 2g/kg to mice significantly antagonizes strychnine nitrate-induced convulsions.A compound decoction (i.e., Wu Hu Zhui Feng San decoction) composed of commercially available white-stiffened silkworm pupae and cicada exuviae reduces mortality from strychnine, pentylenetetrazole, cocaine, and nicotine-induced convulsions in mice. Artificial white-stiffened silkworm pupae decoction also antagonizes strychnine-induced convulsions in mice.
2. Hypnotic Effects: The ethanol-water extract exhibits hypnotic effects in mice and rabbits. In mice, oral administration of 0.5g/20g or subcutaneous injection of 0.25g/20g produced hypnotic potency equivalent to approximately 50mg/kg of subcutaneously injected phenobarbital.
3. Pharmacological Effects of Pupae: Pupae significantly counteracted strychnine-induced convulsions in mice, yielding results consistent with white silkworm pupae. While mortality reduction showed no significant difference between test and control groups, pupae results aligned with white silkworm pupae.In both outcomes, stiff pupae showed slight superiority over white stiff silkworm pupae. Additionally, stiff pupae exhibited inhibitory effects on mouse sarcoma-180 (requiring further confirmation). While they demonstrated inhibitory activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, the effects were not pronounced. Given their readily available source, stiff pupae can serve as a substitute for white stiff silkworm pupae.Pharmacological Study of the Original Silkworm Moth: The original silkworm moth exhibits very low toxicity. It promotes weight gain in immature male mice and significantly increases the weight of the prostate-seminal vesicles and prepuce glands in castrated mice and rats, indicating androgen-like effects.【Toxicity】Using mice weighing 18-22g (equal numbers of males and females), divided into 5 groups of 10 animals each, different doses of water extract from pupae were administered via gavage. The number of deaths within 24 hours was observed. The median lethal dose (LD₅₀) was calculated using the Miller and Trainter method as 44.5±1.4g/kg.Toxic symptoms began appearing at 35 g/kg, manifested as progressively reduced activity, immobility, cyanosis in some individuals, and one death per 10 animals. 【Preparation】 1. White Stiff Silkworm Pupae: Remove silk fibers and hair, wash off dust, sun-dry.
2. Fried Stiff Silkworms: Sprinkle bran into a hot wok until smoke rises. Add stiff silkworms and stir-fry until golden yellow. Remove and sift out bran. Allow to cool. (For every 100 jin of stiff silkworms, use 10 jin of bran) 3.《Lei Gong's Treatise on Preparing Medicinal Herbs》: When using White Stiff Silkworms, first soak them in glutinous rice water for one day. Wait until the silkworm mucus floats on the water surface like snail slime. Then strain them out, dry them over low heat, wipe off the yellow flesh and black mouth armor with a clean cloth, pound them separately, and sift them into powder for use.
4. Rihua's Materia Medica: Remove all silk fibers and eggs before use. Stir-fry evenly.
【Properties】Pungent, salty; neutral nature.
Meridian Tropism: Liver, Lung, Stomach meridians
Functions & Indications: Dispels wind and stops spasms; transforms phlegm and disperses nodules; detoxifies and clears the throat. Treats convulsions, epilepsy, and stroke-induced facial paralysis.
This concludes our detailed introduction to White Stiff Silkworm. We hope this information proves helpful. Wishing you good health and smooth sailing this winter.