Antihepatoma peptide, scolopentide, derived from the centipede scolopendra subspinipes mutilans

Table 1 Small molecular extracts of centipede

Name	Extract methods	Function	Ref.
Scolopendrin I	Cation-exchange chromatography and two steps RP-HPLC	Antimicrobial (G+, G-, and fungi)	[53]
Scolopin 1	(1) Sephadex Gel Chromatography; (2) RP-HPLC; and (3) characterized by MALDI-TOF MS	Antimicrobial (G+, G-, fungi, drug-resistant bacteria)	[37]
Scolopin 2, Scolopin 2-NH2	(1) Sephadex Gel Chromatography; (2) RP-HPLC; and (3) Scolopin2-NH2 was amidation modification from scolopin 2	(1) Antimicrobial (G+, G-, fungi, and drug-resistant bacteria); and (2) inhibit proliferation of cervical cancer HeLa cells	[16,37,45]
LBLP	Transcriptomic data analysis, peptide synthesis	Anti-fungi	[54]
Scolopendrasin II, V, III, X	Next-generation sequencing	(1) Antimicrobial (G+, G-, drug-resistant bacteria, fungi); and (2) regulating immune system to antimicrobial indirectly	[40,55-57]
Scolopendrasin IX	Next-generation sequencing	(1) Regulating immune system to antimicrobial indirectly; and (2) treating autoimmune arthritis	[58]
Scolopendrasin VII	Next-generation sequencing	(1) Antimicrobial (G+, G-, drug-resistant bacteria, and fungi); (2) regulating immune system to antimicrobial indirectly; and (3) inhibiting leukemia U937 and jurkat cells	[17,59,60]
Scolopendin, 1, 2	RNA sequencing	Antimicrobial (G+, G-, drug-resistant bacteria, and fungi)	[41-44]
SerGln-Leu (SQL)	(1) Ultrafiltration, Sephadex G-50 column, Source 15Q anion exchange Column; (2) RP-HPLC C18 column; and (3) characterized by ESI-MS	Anticoagulation and antithrombotic	[7]
Thr-Asn-Gly-Tyr-Thr, (TNGYT)	(1) Sephadex G-50 column; (2) RP-HPLC C18 column; and (3) Characterized by ESI-MS	Anticoagulation and antithrombotic	[38]
SsTx-R12A	Red-headed centipede’s venom cDNA arsenal	Treating autoimmune diseases mediated by T cells	[61]
SsmTX-I	Red-headed centipede’s venom cDNA arsenal	Analgesic	[62]
SsTx	Sephadex G-50 Gel Chromatography and RP-HPLC	Blocking KCNQ potassium channels leads to cardiovascular, respiratory, muscular and nervous system damage	[8]
Ssm6a	Sephadex Gel Chromatography and RP-HPLC	Analgesic	[39]
Haemolymph and tissue extracts	(1) Enzymatic hydrolysis; (2) HPLC; and (3) characterized by MS	Antimicrobial (G+, G-, fungi, viruses, and parasites)	[6]
Lacrain	RP-HPLC and characterized by MS	Antibacterial (G-)	[63]
Pinipesin	(1) Organic solvent extraction; (2) HPLC Jupiter® C18 column; and (3) characterized by MS	Antimicrobial	[5]
AECS	Organic solvent extraction (ethanol)	Inducing apoptosis of human epidermal carcinoma A431 cells and human melanoma HEK293/EGFR, A375 cells	[4,18]
Two isoquinoline alkaloids	(1) Organic solvent extraction (ethanol); (2) sephadex G-25 Gel chromatography; and (3) HPLC	Inducing apoptosis of brain glioma U87 cells	[3]
Centipede water extract, alcohol extract	(1) Water extraction; (2) freeze-thawing with liquid nitrogen, ultrasonic extraction; and (3) organic solvent extraction (ethanol)	No tumour inhibition in S180 and H22 Transplanted tumour mice	[2]
CE, CA	Organic solvent extraction	Inhibiting cervical tumours in vivo	[64]
Centipede chloroform extract	Organic solvent extraction (hexane, chloroform, ethanol)	Reducing central nervous system symptoms of Alzheimer’s disease	[65]
Scom 5	(1) Superdex 75 gel filtration; (2) RESOURCE S ion chromatography; and (3) characterized by LC-MSMS, MALDI-TOF/TOF and protein sequencing techniques	Human allergens	[11]

HPLC: High performance liquid chromatography; RP-HPLC: Reversed-phase high-performance liquid chromatography; MS: Mass spectrum.

Table 2 L₉(3⁴) levels of orthogonal experimental design

Level	Trypsin (g)	Time (h)	Temperature (°C)
1	0.1	3	37
2	0.2	4	46
3	0.3	5	55

Table 3 Primer sequences used for quantitative real-time polymerase chain reaction

Gene	Sequence (5’ to 3’)
GAPDH	F: AGAAGGCTGGGGCTCATTTG	R: AGGGGCCATCCACAGTCTTC
DR4	F: CCAGGCAGCATTGAAGTCAG	R: GTTTCCAGCATCACCAGGGT
DR5	F: CCCTGGAGTGACATCGAATG	R: CAGCCACAATCAAGACTACGG
FADD	F: TGCGGGAGTCACTGAGAATC	R: GGAGGTAGATGCGTCTGAGTTC
Caspase-8	F: GAGAAGCAGCAGCCTTGAAG	R: GACAGTATCCCCGAGGTTTG
Caspase-3	F: CCCTCCTCAGCATCTTATCC	R: TGGTACAGTCAGAGCCAACCT
Cyto-C	F: CACAAGACTGGGCCAAATCTC	R: CCAGGGATGTACTTCTTGGGA
XIAP	F: CTATGCTCACCTAACCCCAAG	R: TTCTGACCAGGCACGATCAC
c-FLIP	F: GGAACCCTCACCTTGTTTCG	R: CTCCTTGCTTATCTTGCCTCG
Bcl-2	F: CCTTCTTTGAGTTCGGTGGG	R: CGGTTCAGGTACTCAGTCATCC
Bax	F: CACCAGCTCTGAGCAGATCA	R: TGTTACTGTCCAGTTCGTCCC

DR4: Death receptor 4; DR5: Death receptor 5; FADD: Fas-associated death domain protein; Cyto-C: Cytochrome C; XIAP: X-chromosome linked inhibitor-of-apoptosis protein; c-FLIP: Cellular Fas associated death domain-like interleukin-1β converting enzyme inhibitory protein; Bcl-2: B-cell lymphoma-2; Bax: Bcl-2-associated X protein.

Table 4 Extract ratio analysis of L₉(3⁴) orthogonal experimental design

Run	A (mg, trypsin)	B (min, time)	C (°C) (temperature)	D (blank)	Extract ratio (%)
1	1	1	1	1	4.55
2	1	2	2	2	5.86
3	1	3	3	3	4.32
4	2	1	2	3	5.63
5	2	2	3	1	4.21
6	2	3	1	2	3.98
7	3	1	3	2	3.34
8	3	2	1	3	3.68
9	3	3	2	1	5.94
K1	14.73	13.52	12.21	14.70	-
K2	13.82	16.01	14.83	13.18	-
K3	12.96	11.64	11.87	13.63	-
R	1.77	4.37	2.96	1.52	-

Kij parameters in a first level of the first i-j-average quality index; I = 1, 2, 3, representative of 3 levels; j = 1, 2, 3; representing three factors.

Table 5 Inhibitory effects of crude centipede peptides on HepG2 cells in different conditions

Concentration (mg/mL)	Suppression ratio (%)
	Group 1	Group 2	Group 3	Group 4	Group 5	Group 6	Group 7	Group 8	Group 9
0.039	12.510	6.880	12.070	5.394	3.389	3.213	0.570	1.641	7.094
0.078	22.270	11.240	13.060	16.430	12.890	4.709	2.280	4.540	9.883
0.156	45.770	36.430	45.680	52.290	18.610	16.620	26.110	11.540	33.170
0.3125	85.510	85.040	88.540	94.360	68.110	63.660	58.500	64.170	76.610
0.625	89.090	86.060	92.440	94.520	94.170	94.96	83.200	95.180	94.570
1.250	91.840	87.490	93.050	94.770	96.780	95.730	94.660	95.300	96.000
2.500	92.070	89.470	93.430	94.690	96.940	96.670	95.540	95.670	96.920
5.000	92.750	92.000	95.800	96.680	97.720	97.780	95.880	95.790	97.650
IC50 (mg/mL)	0.457	0.310	0.480	0.360	0.584	0.681	0.812	0.757	0.278
Extract ratio (%)	4.550	5.860	4.320	5.630	4.210	3.980	3.340	3.680	5.940