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Proceeding Paper

Stokesia laevis Ethanolic Extract Activity on the Normal and Malignant Murine Cell Line Viability L969 and B16 †

National Institute for Chemical-Pharmaceutical Research and Development, 112 Vitan Av., 031299 Bucharest, Romania
*
Author to whom correspondence should be addressed.
Presented at the 24th International Electronic Conference on Synthetic Organic Chemistry, 15 November–15 December 2020; Available online: https://ecsoc-24.sciforum.net/.
Published: 14 November 2020

Abstract

:
Stokesia laevis (common name Stokes aster) ethanolic extract (Slae26) containing 5 mg GAE/mL extract was investigated to establish cytotoxicity and anti-proliferative effects. The assays were performed on normal murine fibroblast cell line L929 and malignant murine melanoma cell line B16, respectively; for the first time in literature data, potential cytotoxic and anti-proliferative effects of the ethanolic extract from S. laevis on both, normal murine fibroblast cell line L929, and murine melanoma cell line B16 have been proved. The study is supplemented by molecular docking simulations of the major components of Slae26 against human tyrosinase receptor, to evaluate possible melanogenesis inhibition.

1. Introduction

According to the specialized data, the cutaneous malignant melanoma is the most aggressive type of skin cancer [1]. Data also indicate that the skin melanoma is the most commonly occurring cancer worldwide; the most affected are Australian and New Zealand peoples, followed by Caucasian peoples [2]. Due to high aggressiveness and chemical therapy resistance [3], there are many attempts to find new therapy combinations and antitumor agents or synergistic compounds able to fight against skin melanoma cancer resistance. Among these, several plant species and specific plant compounds indicated promising results, inhibitory activity by in vitro testing of human and murine melanoma cell lines and murine melanoma models, respectively [4].
Aiming to extend the authors’ previously published work [5], the present paper aims to study the cytotoxic and anti-proliferative potential of the standardized ethanolic extract (Slae26) from Stokesia laevis (J. Hill, fam. Asteraceae), 5 mg GAE/mL extract, on normal murine fibroblast cell line L929 and malignant murine melanoma cell line B16, respectively; the predominant compounds in Slae26 (HPTLC analysis) are caffeic acid and luteolin derivates [5].

2. Materials and Methods

Briefly, the test vegetal extract was obtained from dried and powdered aerial part of S. laevis extracted with 70% (v/v) ethanol at the boiling temperature. The resulted ethanolic extract was analyzed concerning quantitative and qualitative aspects [5], then prepared as standardized 5 mg total phenols content expressed as gallic acid derivates [GAE] per 1 mL 40% ethanol solution, v/v, namely Slae26; the Slae26 dilution series (0.5, 1, 5, 10, 25, 50 and 100 μg GAE/mL, test vegetal samples) and corresponding 40% ethanol solvent dilution series (0.04, 0.08, 0.8, 2, 4 and 8% ethanol, v/v, control samples) were used for further in vitro cell studies.
The in vitro cytotoxicity and anti-proliferative assays were done according to the Technical Bulletin of Promega Corporation CellTiter 96 AQueous One solution Cell Proliferation Assay as described in previous study [5]. Briefly, after 20 h (cytotoxicity test) and, respectively, 20 and 44 h (antiproliferative test) of cell exposure, the absorbance of the test samples (Slae26 dilution series) face to control sample (40% ethanol dilution series) were measured at 490 nm (using Chameleon V Plate Reader, LKB Instruments, Mount Waverley, Australia). The recorded values were used for the estimation of the cell viability (see Equation (1)). Results are calculated as mean ± SD, n = 3.
%   cell   viability = A 490   o f   t r e a t e d   c e l l s A 490   o f   c o n t r o l   c e l l s 100
The molecular docking study was realized using CLC Drug, Discovery Work Bench. Protein fragment, human tyrosinase related protein 1 [6] in complex with kojic acid (PDB ID 5M8M) [7] was imported from Protein Data Bank. Ligands’ structures, components of Slae26 (Caffeic acid, Chlorogenic acid, Luteolin, Luteolin-5-O-glucoside, Luteolin-7-O-glucoside, Luteolin-6-C-glucoside, Luteolin-8-C-glucoside, Luteolin-7,3′-di-O-glucoside and Luteolin 3,4′-di-O-glucoside) were imported from PubChem (https://pubchem.ncbi.nlm.nih.gov, accessed on 5 November 2020), and docked into 107.01 Å3 binding pocket.

3. Results

3.1. Cytotoxicity and Anti-Proliferative Assays

Figure 1 shows the results on the Slae26 dilution series tested on (a) murine fibroblast cell line L929 and (b) murine melanoma cell line B16, compared to the control negative cell series (40% ethanol solvent series). Therefore, the cytotoxicity test on the normal murine fibroblast cell line L929 indicated that Slae26 test sample concentrations less than 25 μg/mL induced moderate stimulating effects on the L929 cell line viability (up to 20% increase), after that there were noticed augmented inhibitory activity (up to 84% cell viability decrease at 100 μg/mL); the anti-proliferative test indicated that, less than 10 μg/mL extract at 24 h/h, and less than 5 μg/mL at 48 h, Slae26 induced stimulating effects (up to 25%, and up to 7% cell viability increase, respectively), after which the same decrease in cell viability was observed (inhibition of cell viability up to 65% and 81%, at 24 h and 48 h, respectively).
In the case of malignant murine melanoma cell line B16, the cytotoxicity test shown the same stimulating effects on the B16 cell line viability (up to 8% stimulation of cell viability at the test sample concentrations less than 10 μg/mL), followed by a severe decrease in cell viability at higher concentrations (up to 90% cell viability decrease at 100 μg/mL); similarly, the anti-proliferative test indicated less than 10 μg/mL extract at 24 h, and less than 5 μg/mL at 48 h, Slae26 extract induced stimulating effects on B16 cell line viability (up to 20% and up to 18%, at 24 h and 48 h, respectively), followed by a sharp decrease in cell viability at 24 and 48 h (up to 79% and up to 93% inhibition of cell viability at 24 h and 48 h at 100 μg/mL, respectively).

3.2. Molecular Docking Results

All investigated structures reveal greater docking score than the co-crystallized ligand (kojic acid). The chart of obtained values for docking score is presented in Figure 2. The best result is given for L-7-O-glucoside (66.76). For all compounds, the interactions as hydrogen bond type and length formed with the amino acids residues form the active binding site of the tyrosinase, are listed in Table 1, along with results obtained for the natural ligand (KOJ A514 = Kojic acid). Two of hydrogen bonds interactions formed with the same amino acid residues, as kojic acid forms, SER394 and HIS215, respectively, occur in the complexes of investigated ligands with human tyrosinase related protein 1 fragment, excepting di-glucosides (L-3′,4′-di-O-glucoside and L-3′,4′-di-O-glucoside). Only HIS215 is present in their interacting amino acids group, but don’t establish interactions with the di-glucosides.
Figure 3 illustrates the arbitrary numbering scheme for constitutive atoms of investigated structures, as given for the most stable conformers of each structures, obtained after energy minimization using Spartan Software [8]. Figure 4 depicts the intermolecular interactions of investigated ligands with 5M8M, illustrating the hydrogen bonds formed by the hydroxyl (O sp3) or carboxyl group (O sp2) of investigated structures and amino acids residues from the binding pocket of the protein fragment, directly interacting.

4. Discussion

Very extensive studies summing 582 extracted samples obtained from 370 plants [9] indicated several plants derived products and specific phytocompounds (there were investigated 118 separate compounds) as being able to act as inhibitors of B16F-10 melanoma metastatic cell line viability. Therefore, the most effective plant derived products were Mangifera indica-barks, leaves and seeds extracts, Annona cherimola, Annona muricata and Annona squamosa-bark, leaves, stems and twigs extracts, Anthriscus sylvestris-fruits, leaves and roots extracts, Osmorhiza aristata-aerial parts extracts, Araucaria heterophylla-leaves extracts, Tylophora ovata and Tylophora tanakae-fresh leaves, twigs and aerial parts extracts, Crepidiastrum lanceolatum-aerial parts extracts, Garcinia subelliptica-barks extracts, Luffa acutangula and Momordica cochinchinensis-seeds extracts, Juniperus rigida and Thuja occidentalis-leaves extracts, Persea americana-leaves extracts and Coptis japonica-rhizomes extracts. Plant derived products inhibitory activity (EC50) was mostly evaluated as less than 100 µg/mL (70%), 12% of them being evaluated as less than 12.5 µg/mL. Moreover, lignan compounds were proved as the most effective inhibitors of B16F-10 melanoma metastatic cell line viability; deoxypodophyllotoxin and morensin proved the most augmented antiproliferative effects being evaluated at EC50 = 0.21 and 0.23 µg/mL respectively. Other polyphenols compounds such as apigenin (EC50 = 25 µg/mL), luteolin (EC50 = 21 µg/mL), baicalein (EC50 = 11 µg/mL), gallic acid and derivates (EC50 = 2–9 µg/mL) and hydroxycinnamic acid derivates, also were proved to provide certain anti-proliferative effects against B16F-10 melanoma metastatic cell line viability [9].
The present work suggests certain cytotoxic and antiproliferative activity of 40% ethanolic extract (Slae26) from Stokesia laevis plant species (the aerial part), upon normal murine fibroblast cell line L929 and murine melanoma cell line B16; also, HPTLC analysis of Slae26 indicated the presence of two major polyphenols subclasses, caffeic acid and luteolin derivates, punctually the predominance of caffeic acid, chlorogenic acid, luteolin and luteolin-7-O-glucoside [5]. Also, the docking results indicated similar interactions for the co-crystallized kojic acid and the nine vegetal compounds tested (punctually, Luteolin (L), L-7-O-glucoside, L-5-O-glucoside, L-6-C-glucoside, L-8-C-glucoside, L-3′,4′-di-O-glucoside, L-7, 3′-di-O-glucoside, Caffeic acid and Chlorogenic acid); furthermore, there were noticed interactions with the same amino acid residues, by hydrogen bonds formed with O sp3 of SER394, and N sp2 of HIS215, respectively, except for di-glucosides. In addition, due to the numerous hydroxyl groups of our investigated structures, more interactions in the protein-complex occur and higher docking score are revealed. Therefore, docking results suggest the ability of luteolin and caffeic acid derivatives to act as potential skin melanoma cancer inhibitors.

5. Conclusions

For the first time in literature data, potential cytotoxic and anti-proliferative effects of the ethanolic extract from S. aster on both, normal murine fibroblast cell line L929, and murine melanoma cell line B16 have been proved. Molecular docking approach on the major components of Slae26 against human tyrosinase receptor has reveal possible melanogenesis inhibition.

Author Contributions

Conceptualization, L.C.P. and A.S.; methodology, A.S. and G.N.; software, L.P., A.S. and B.A.; validation, G.N. and L.P.; formal analysis, B.A.; investigation, A.S., G.N. and I.T.; resources, G.N.; data curation, L.C.P.; writing—original draft preparation, A.S.; writing—review and editing, L.C.P.; visualization, G.N.; supervision, L.C.P.; project administration, L.C.P.; funding acquisition, L.C.P. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the ANCSI POC-A1-A1.2.3-G-2015 (Project ID P_40_406, SMIS 105542, Contract no. 60/05.09.2016).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Conflicts of Interest

The authors declare no conflict of interest.

References

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  2. Skin Cancer Statistics. Available online: https://www.wcrf.org/dietandcancer/cancer-trends/skin-cancer-statistics (accessed on 24 October 2020).
  3. Kalal, B.S.; Upadhya, D.; Pai, V.R. Chemotherapy resistance mechanisms in advanced skin cancer. Oncol. Rev. 2017, 11, 326. [Google Scholar] [CrossRef] [PubMed]
  4. Chinembiri, N.T.; du Plessis, L.H.; Gerber, M.; Hamman, J.H.; du Plessis, J. Review of natural compounds for potential skin cancer treatment. Molecules 2014, 19, 11679–11721. [Google Scholar] [CrossRef] [PubMed]
  5. Pirvu, L.; Neagu, G.; Terchescu, I.; Albu, B.; Stefaniu, A. Comparative studies of two vegetal extracts from Stokesia laevis and Geranium pratense: Polyphenol profile, cytotoxic effect and antiproliferative activity. Open Chem. 2020, 18, 488–502. [Google Scholar] [CrossRef]
  6. Lai, X.; Wichers, H.J.; Soler-Lopez, M.; Dijkstra, B.W. Structure of human tyrosinase related protein 1 reveals a binuclear zinc active site important for melanogenesis. Angew. Chem. Int. Ed. 2017, 56, 9812–9815. [Google Scholar] [CrossRef] [PubMed]
  7. Lai, X.; Soler-Lopez, M.; Wichers, H.J.; Dijkstra, B.W. Crystal Structure of Human Tyrosinase Related Protein 1 in Complex with Kojic Acid; PDB ID: 5M8M. Deposited on: 2016-10-29. Available online: https://www.rcsb.org/structure/5M8M (accessed on 5 November 2020).
  8. Shao, Y.; Molnar, L.F.; Jung, Y.; Kussmann, J.; Ochsenfeld, C.; Gilbert, A.T.B.; Slipchenko, L.V.; Levchenko, S.V.; O’Neill, D.P.; DiStasio, R.A., Jr.; et al. Advances in methods and algorithms in a modern quantum chemistry program package. Phys. Chem. Chem. Phys. 2006, 8, 3172–3191. [Google Scholar] [CrossRef] [PubMed]
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Figure 1. Cytotoxic and antiproliferative effects (cell viability, %) of Slae26 dilution series tested on (a) murine fibroblast cell line L929 and (b) murine melanoma cell line B16, compared to control negative cell lines (40% ethanol solvent series); n = 3, ±SD (%).
Figure 1. Cytotoxic and antiproliferative effects (cell viability, %) of Slae26 dilution series tested on (a) murine fibroblast cell line L929 and (b) murine melanoma cell line B16, compared to control negative cell lines (40% ethanol solvent series); n = 3, ±SD (%).
Chemproc 03 00042 g001
Figure 2. Docking scores for Luteolin (L) derivatives, caffeic and chlorogenic acids, against human tyrosinase related protein 1 (PDB ID 5M8M).
Figure 2. Docking scores for Luteolin (L) derivatives, caffeic and chlorogenic acids, against human tyrosinase related protein 1 (PDB ID 5M8M).
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Figure 3. Atoms labels numbering for: (a) L; (b) L-7-O-glucoside; (c) L-5-O-glucoside; (d) L-6-C-glucoside; (e) L-8-C-glucoside; (f) L-3′,4′-di-O-glucoside; (g) L-7,3′-di-O-glucoside; (h) caffeic acid; (i) chlorogenic acid.
Figure 3. Atoms labels numbering for: (a) L; (b) L-7-O-glucoside; (c) L-5-O-glucoside; (d) L-6-C-glucoside; (e) L-8-C-glucoside; (f) L-3′,4′-di-O-glucoside; (g) L-7,3′-di-O-glucoside; (h) caffeic acid; (i) chlorogenic acid.
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Figure 4. Intermolecular interactions of investigated ligands with 5M8M, as hydrogen bonds formed by: (a) Luteolin (L); (b) L-7-O-glucoside; (c) L-5-O-glucoside; (d) L-6-C-glucoside; (e) L-8-C-glucoside; (f) L-3′,4′-di-O-glucoside; (g) L-7,3′-di-O-glucoside; (h) caffeic acid and (i) chlorogenic acid.
Figure 4. Intermolecular interactions of investigated ligands with 5M8M, as hydrogen bonds formed by: (a) Luteolin (L); (b) L-7-O-glucoside; (c) L-5-O-glucoside; (d) L-6-C-glucoside; (e) L-8-C-glucoside; (f) L-3′,4′-di-O-glucoside; (g) L-7,3′-di-O-glucoside; (h) caffeic acid and (i) chlorogenic acid.
Chemproc 03 00042 g004aChemproc 03 00042 g004b
Table 1. Intermolecular interactions between ligands and 5M8M and docking results.
Table 1. Intermolecular interactions between ligands and 5M8M and docking results.
LigandScoreRMSDInteracting Group (Chain A)Hydrogen BondLength (Å)
KOJ A514 (grey)−39.790.06HIS215, HIS192, THR391, PRO395, SER394, PHE400, GLN390, GLY388, GLY389, LEU382, HIS381, ARG374, LEE379, ASN378, HIS377, TYR362Osp3 (O2)-Osp3 SER3942.889
Osp2 (O3)-Nsp2 HIS2153.203
L (magenta rose)−55.020.02ARG374, TYR362, HIS377, HIS401, PHE220, HIS224, ARG321, LEU382, ASN378, HIS381, PHE400, HIS215, HIS192, PRO395, SER394, GLY388, GLY389, THR391, GLN390, HIS392Osp2 (O3)-Nsp2 ARG3742.969
Osp3 (O2)-Nsp2 ARG3742.846
Osp 3(O2)-Nsp2 ARG3742.885
Osp3 (O2)-Nsp2 ARG3213.174
Osp2 (O1)-Osp3 THR3913.166
Osp3 (O5)-Nsp2 HIS3772.982
Osp3 (O5)-Nsp2 HIS2153.161
Osp3 (O6)-Nsp2 HIS1923.134
Osp3 (O6)-Osp3 SER3942.968
Osp3 (O6)-Nsp2 HIS3813.387
L-7-O-glucoside
(green)
−66.761.27HIS192, HIS224, PHE220, HIS215, HIS404, THR391, PHE400, SER394, GLU360, GLN390, GLY388, THR387, HIS377, ASN378, HIS381, GLY389, TYR362, ARG374, GLY386, LEU384, ASN385, LEU382, PHE383, ASN318, ARG321Osp2 (O9)-Nsp2 ARG3742.825
Osp3 (O8)-Nsp2 ARG3742.552
Osp3 (O6)-Nsp2 ASN3182.967
Osp3 (O6)-Nsp2 ASN3853.103
Osp3 (O4)-Nsp2 GLY3863.039
Osp3 (O4)-Osp2 GLY3863.050
Osp3 (O10)-Nsp2 HIS3813.173
Osp3 (O10)-Osp3 SER3942.906
Osp3 (O11)-Nsp2 HIS2153.985
Osp3 (O11)-Nsp2 HIS3813.084
L-5-O-glucoside
(light blue)
−54.210.13ARG321, ARG374, LEU382, TYR362, ASN378, HIS381, HIS377, GLU360, HIS404, PHE220, HIS224, HIS192, HIS215, PHE400, THR391, SER394, GLN390, GLY388, GLY389Osp2 (O9)-Nsp2ARG3743.038
Osp2 (O9)-Nsp2ARG3743.030
Osp3(O5)-Nsp2ARG3742.820
Osp3(O5)-Nsp2ARG3212.713
Osp2(O7)-Osp3THR3912.744
Osp3(O11)-Nsp2HIS2153.103
Osp3(O11)-Nsp2HIS3813.225
Osp3(O10)-Osp3SER3942.642
L-6-C-glucoside
(purple)
−61.550.15ARG374, TYR362, GLU360, HIS377, ASN378, HIS404, PHE220, HIS224, HIS215, HIS192, HIS392, THR391, SER394, GLN390, GLY388, GLY389, HIS381, LEU382, ARG321, ASN318Osp3(O9)-Nsp2 ARG3742.423
Osp3(O9)-Nsp2 ARG3743.156
Osp3(O6)-Nsp2 ARG3743.110
Osp3(O6)-Nsp2 ARG3213.115
Osp3(O2)-Nsp2 ARG3212.990
Osp3(O2)-Nsp2 ARG3212.901
Osp3(O1)-Nsp2 ARG3212.967
Osp3(O4)-Nsp2 ARG3212.831
Osp3(O10)-Osp3 SER3942.502
Osp3(O11)-Nsp2 HIS3813.248
Osp3(O11)-Nsp2HIS2153.113
Osp2(O8)-Osp3THR3913.180
L-8-C-glucoside
(brown)
−53.810.03HIS192, HIS392, SER394, PHE400, THR391, GLN390, GLY388, GLY389, HIS381, LEU382, ARG321, ARG374, TYR362, ASN378, HIS377, GLU360, PHE220, HIS215, HIS204, HIS224Osp2 (O9)- Nsp2ARG3742.884
Osp2 (O8)-Nsp2ARG3742.569
Osp2 (O8)-Nsp2ARG3742.592
Osp2 (O8)-Nsp2 ARG3213.083
Osp3 (O10)-Nsp2 HIS2152.751
Osp3 (O11)-Nsp2 HIS1923.134
Osp3 (O11)-Osp3 SER3943.060
Osp3 (O2)-Osp3 THR3912.451
L-3′,4′-di-O-glucoside
(red brown)
−60.912.68GLU216, HIS215, ASP212, VAL211, VAL196, GLY209, LYS198, LYS197, LEU293, HIS392, THR391, GLN390, GLY388, GLY389, ARG321, LEU382, HIS381, LEU379, ASN378, ARG374, HIS377, TYR362Osp2 (O3)-Nsp2 HIS3922.789
Osp3 (O4)-Osp3 ASP2123.001
Osp2 (O1)-Osp3 THR3912.707
Osp3 (O12)-Osp3 THR3913.271
Osp3 (O13)-Osp3 THR3912.906
Osp3 (O13)-Nsp2 THR3913.050
Osp3 (O13)-Osp2 GLY3892.856
Osp3 (O14)-Osp2 ASN3783.046
Osp3 (O15)-Osp3 TYR3622.656
Osp3 (O16)-Nsp2 ARG3743.307
Osp3 (O16)-Nsp2 ARG3742.671
Osp3 (O9)-Nsp2 ARG3213.022
Osp3 (O9)-Nsp2 ARG3212.909
Osp3 (O10)-Nsp2 ARG3743.073
L-7,3′-di-O-glucoside
(blue)
−52.442.43LEU293, HIS392, THR391, GLN390, GLY389, HIS381, LEU382, ARG321, ASN378, HIS377, ARG374, GLU360, TYR362, TYR348, GLU216, HIS215, GLU210, VAL211, ASP212, GLY209, VAL196, LYS198, LYS197Osp2 (O13)-Osp3 THR3912.836
Osp2 (O13)-Nsp2 THR3913.192
Osp3 (O14)-Osp2 VAL1962.698
Osp3 (O10)-Osp2 VAL1963.094
Osp3 (O10)-Osp2 VAL2112.913
Osp3 (O10)-Osp2 GLY2093.240
Osp3 (O8)-Osp2 VAL2112.867
Osp3 (O8)-Osp2 GLY2092.823
Osp3 (O7)-Osp3 GLU2162.674
Osp3 (O12)-Osp3 GLU2163.054
Osp3 (O1)-Osp3 THR3913.157
Osp3 (O5)-Osp3 TYR3622.920
Osp3 (O5)-Osp2 ASN3783.089
Osp3 (O4)-Nsp2 ARG3743.148
Osp3 (O4)-Nsp2 ARG3742.554
Caffeic acid
(orange brown)
−47.630.05PHE220, HIS215, HIS224, HIS192, THR391, PRO395, HIS404, SER394, PHE400, GLN390, GLY388, GLY389, LEU382, HIS381, ASN378, HIS307, ARG374, TYR362, GLU360Osp3 (O3)-Nsp2 ARG3743.146
Osp2 (O4)-Nsp2 ARG3742.860
Osp2 (O4)-Nsp2 ASN3783.034
Osp3 (O1)-Nsp2 HIS3773.195
Osp3 (O1)-Nsp2 HIS2153.019
Osp3 (O1)-Nsp2 HIS3813.374
Osp3 (O2)-Osp3 SER3942.424
Chlorogenic acid
(light purple)
−56.082.05ARG321, ARG374, TYR362, LEU382, ASN378, HIS377, GLU360, HIS381, HIS404, PHE220, HIS224, HIS215, PHE400, GLY389, GLY388, GLN390, SER394, THR391, PRO395, HIS192Osp3 (O9)-Nsp2 HIS3813.289
Osp3 (O9)-Nsp2 HIS2153.031
Osp3 (O8)-Osp3 SER3942.523
Osp2 (O7)-Nsp2 ARG3742.854
Osp2 (O7)-Nsp2 ARG3743.072
Osp3 (O2)-Nsp2 ARG3213.107
Osp3 (O2)-Nsp2 ARG3212.738
Osp3 (O4)-Nsp2 ARG3212.862
Osp3 (O3)-Osp2 GLY3892.817
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Neagu, G.; Stefaniu, A.; Albu, B.; Terchescu, I.; Pintilie, L.; Pirvu, L.C. Stokesia laevis Ethanolic Extract Activity on the Normal and Malignant Murine Cell Line Viability L969 and B16. Chem. Proc. 2021, 3, 42. https://0-doi-org.brum.beds.ac.uk/10.3390/ecsoc-24-08318

AMA Style

Neagu G, Stefaniu A, Albu B, Terchescu I, Pintilie L, Pirvu LC. Stokesia laevis Ethanolic Extract Activity on the Normal and Malignant Murine Cell Line Viability L969 and B16. Chemistry Proceedings. 2021; 3(1):42. https://0-doi-org.brum.beds.ac.uk/10.3390/ecsoc-24-08318

Chicago/Turabian Style

Neagu, Georgeta, Amalia Stefaniu, Bujor Albu, Iulian Terchescu, Lucia Pintilie, and Lucia Camelia Pirvu. 2021. "Stokesia laevis Ethanolic Extract Activity on the Normal and Malignant Murine Cell Line Viability L969 and B16" Chemistry Proceedings 3, no. 1: 42. https://0-doi-org.brum.beds.ac.uk/10.3390/ecsoc-24-08318

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