Journal of Natural Products
Note
́
continuous flux of gas (95% N2/5% CO2). The chamber was sealed
and placed in an incubator at 37 °C for 4 h OGD. To terminate the
oxygen−glucose deprivation, the cells were returned to the normal
culture media in a normoxic incubator for 24 h of reoxygenation.
Compounds were added 4 h prior to the induction of OGD. Control
cell cultures that were not deprived of oxygen and glucose were placed
in norm-oxygenated DMEM containing glucose. Cell viability was
measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazo-
lium bromide (MTT) assay.
Ex Vivo Stability Studies of Peptides in Diluted Rat Serum.
The stabilities of synthetic 1−3 and their all L-amino acids isomers
were studied in commercially available pooled rat serum diluted to
50% with distilled H2O. Each peptide (1.5 mg) was dissolved in 2 mL
of pooled sterile rat serum. Peptides were incubated at 37 °C. After
incubation periods of 0, 5, 10, 15, and 30 min and 1, 1.5, 2, 4, 6, 8, 10,
and 24 h, 100 μL serum medium was taken out and added with a 500
μL mixture of MeOH and CH3CN (1:2, v/v) to precipitate the serum
proteins. After being stored at 4 °C for 30 min, the mixture was
centrifuged at 13 000 r/min for 10 min. The remaining amounts of
peptides were determined using HPLC [flow rate: 1 mL/min;
detection wavelength: 214 nm; mobile phase: 10−35% CH3CN−H2O
(0.1% TFA) from 0 to 30 min]. All experiments were carried out
three times.26
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ASSOCIATED CONTENT
* Supporting Information
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UPLC-QTOF/MS analysis of the saline extract of the
fresh bodies of Whitmania pigra Whitman (PDF)
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AUTHOR INFORMATION
Corresponding Authors
ORCID
Mullegger, J.; Sander, V.; Fehrer, C.; Barra, D.; Kreil, G. Proc. Natl.
̈
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Acad. Sci. U. S. A. 2005, 102, 4235−4239.
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F. Proc. Natl. Acad. Sci. U. S. A. 2005, 102, 413−418.
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Toxicol. In Vitro 2011, 25, 177−184.
(26) Li, Y.; Lei, Y.; Wagner, E.; Xie, C.; Lu, W. Y.; Zhu, J. H.; Shen,
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Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This work was supported by the National Key R&D Program
of China (No. 2017YFC1703800), the Program for the
National Natural Science Foundation of China (Nos.
81822042, 81573307), the Local Innovative and Research
Teams Project of Guangdong Pearl River Talents Program
(2017BT01Y036), the Guangdong Natural Science Founda-
tion for Distinguished Young Scholars (No.
2015A030306022), and the Science and Technology Planning
Project of Guangdong Province (No. 2016B030301004).
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