Psychoactive Plant Database - Neuroactive Phytochemical Collection

1. Langmuir. 2024 Jun 11;40(23):12264-12275. doi: 10.1021/acs.langmuir.4c01403. 
Epub 2024 May 28.

Stability of Liposomal Membrane of Hemoglobin-Vesicles (Artificial Red Cells) 
for Over Years of Storage Evaluated Using Liquid Chromatography-Mass 
Spectrometry.

Kure T(1), Ochiai R(2), Sakai H(1).

Author information:
(1)Department of Chemistry, Nara Medical University, 840 Shijo-cho, Kashihara 
634-8521, Japan.
(2)Pharmaceuticals and Life Sciences Division, Shimadzu Techno-Research, Inc., 
Kyoto 604-8436, Japan.

Hemoglobin-Vesicles (Hb-V) are artificial oxygen carriers encapsulating a 
purified and concentrated Hb solution in liposomes composed of 
1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), cholesterol, 
1,5-O-dihexadecyl-N-succinyl-l-glutamate (DHSG), and 
1,2-distearoyl-sn-glycero-3-phosphatidylethanolamine-N-poly(ethylene glycol) 
(PEG5000) (DSPE-PEG). The safety and efficacy of Hb-V have been studied 
extensively by both preclinical and clinical test methods. Deoxygenation of Hb-V 
prevents autoxidation of Hb and can extend its shelf life to 2 years at room 
temperature. However, the lipid components raise concerns about hydrolysis 
because Hb-V is dispersed in saline. For this study, we attempted to estimate 
the lipid degradation of long-term stored Hb-V using liquid chromatography-mass 
spectrometry. Analyses of lipid components extracted from the stored Hb-V showed 
that the degradation increased depending on the storage temperature. The 
calculated % remaining of intact lipids of Hb-V were 98.1% after 4 years and 
90.4% after 7.2 years at 4 °C, 95.8% after 1 year and 86.7% after 2 years at 25 
°C, and 85.6% after 6 months at 40 °C. The main degradation products were 
lyso-PC and palmitic acid which are hydrolyzed at the ester bond of DPPC. A few 
hydrolyzed products of DHSG and DSPE-PEG were also detected in Hb-V, but almost 
no degradation or oxidation products derived from cholesterol could be 
identified. A shear test of Hb-V at 1500 s-1 showed no significant increase in 
Hb leakage after storage of 2 years at 25 °C and 6 months at 40 °C. Lipid 
degradation products including free fatty acids would decrease the pH of the 
Hb-V dispersion and synergistically facilitate degradation, but it maintained pH 
6.5 during 6 years at 4 °C, 2 years at 25 °C, and 3 months at 40 °C because of 
its high buffering capacity. These results indicate that the storage conditions 
for Hb-V are appropriate to minimize lipid degradation in the long term.

DOI: 10.1021/acs.langmuir.4c01403
PMID: 38804272 [Indexed for MEDLINE]


2. J Phys Chem B. 2023 Apr 20;127(15):3505-3515. doi: 10.1021/acs.jpcb.2c08412. 
Epub 2023 Apr 5.

Relevance of Surface Adsorption and Aqueous Complexation for the Separation of 
Co(II), Ni(II), and Fe(III).

Sun P(1)(2), Binter EA(1), Vo T(1), Benjamin I(3), Bera MK(2), Lin B(2), Bu 
W(2), Schlossman ML(1).

Author information:
(1)Department of Physics, University of Illinois at Chicago, Chicago, Illinois 
60607, United States.
(2)NSF's ChemMatCARS, Pritzker School of Molecular Engineering, University of 
Chicago, Chicago, Illinois 60637, United States.
(3)Department of Chemistry and Biochemistry, University of California, Santa 
Cruz, California 95064, United States.

During the solvent extraction of metal ions from an aqueous to an organic phase, 
organic-soluble extractants selectively target aqueous-soluble ions for 
transport into the organic phase. In the case of extractants that are also 
soluble in the aqueous phase, our recent studies of lanthanide ion-extractant 
complexes at the surface of aqueous solutions suggested that ion-extractant 
complexation in the aqueous phase can hinder the solvent extraction process. 
Here, we investigate a similar phenomenon relevant to the separation of Co(II), 
Ni(II), and Fe(III). X-ray fluorescence near total reflection and tensiometry 
are used to characterize ion adsorption behavior at the surface of aqueous 
solutions containing water-soluble extractants, either bis(2-ethylhexyl) 
phosphoric acid (HDEHP) or 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester 
(HEHEHP), as well as adsorption to a monolayer of water-insoluble extractant 
dihexadecyl phosphoric acid (DHDP) at the aqueous-vapor interface. Competitive 
adsorption of Ni(II) and Fe(III) utilizing either HDEHP or DHDP illustrates the 
essential feature of the recent lanthanide studies that the ion, which is 
preferentially extracted in liquid-liquid extraction, Fe(III), is found 
preferentially adsorbed to the water-vapor interface only in the presence of the 
water-insoluble extractant DHDP. A more subtle competition produces comparable 
adsorption behavior of Co(II) and Ni(II) at the surfaces of both HDEHP- and 
HEHEHP-aqueous solutions in spite of the known preference for Co(II) under 
solvent extraction conditions. Comparison experiments with a monolayer of DHDP 
reveal that Co(II) is preferentially adsorbed to the surface. This preference 
for Co(II) is also supported by molecular dynamics simulations of the potential 
of mean force of ions interacting with the soluble extractants in water. These 
results highlight the possibility that complexation of extractants and ions in 
the aqueous phase can alter selectivity in the solvent extraction of critical 
elements.

DOI: 10.1021/acs.jpcb.2c08412
PMID: 37018762


3. Protein Expr Purif. 2016 Aug;124:62-7. doi: 10.1016/j.pep.2016.05.015. Epub
2016  May 27.

Impact of purification conditions and history on A2A adenosine receptor 
activity: The role of CHAPS and lipids.

Naranjo AN(1), McNeely PM(1), Katsaras J(2), Robinson AS(3).

Author information:
(1)Department of Chemical and Biomolecular Engineering, University of Delaware, 
Newark, DE 19711, United States.
(2)Biology and Soft Matter Division, Neutron Sciences Directorate, Oak Ridge 
National Laboratory, Oak Ridge, TN 37831-6100, United States; Department of 
Physics and Astronomy, The University of Tennessee, Knoxville, TN 37996-1200, 
United States; Joint Institute for Neutron Sciences, Oak Ridge National 
Laboratory, Oak Ridge, TN 37831-6453, United States.
(3)Department of Chemical and Biomolecular Engineering, University of Delaware, 
Newark, DE 19711, United States; Department of Chemical and Biomolecular 
Engineering, 300 Lindy Boggs Laboratory, Tulane University, New Orleans, LA 
70118, United States. Electronic address: asr@tulane.edu.

The adenosine A2A receptor (A2AR) is a much-studied class A G protein-coupled 
receptor (GPCR). For biophysical studies, A2AR is commonly purified in a 
detergent mixture of dodecylmaltoside (DDM), 3-(3-cholamidopropyl) 
dimethylammoniopropane sulfonate (CHAPS), and cholesteryl hemisuccinate (CHS). 
Here we studied the effects of CHAPS on the ligand binding activity and 
stability of wild type, full-length human A2AR. We also tested the cholesterol 
requirement for maintaining the active conformation of the receptor when 
solubilized in detergent micelles. To this end, the receptor was purified using 
DDM, DDM/CHAPS, or the short hydrocarbon chain lipid 
1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC, di-6:0PC). After 
solubilization in DDM, DDM/CHAPS, or DHPC micelles, although A2AR was found to 
retain its native-like fold, its binding ability was significantly compromised 
compared to DDM or DDM/CHAPS with CHS. It therefore appears that although 
cholesterol is not needed for A2AR to retain a native-like, α-helical 
conformation, it may be a critical component for high affinity ligand binding. 
Further, this result suggests that the conformational differences between the 
active and inactive protein may be so subtle that commonly used spectroscopic 
methods are unable to differentiate between the two forms, highlighting the need 
for activity measurements. The studies presented in this paper also underline 
the importance of the protein's purification history; i.e., detergents that 
interact with the protein during purification affect the ligand binding 
properties of the receptor in an irreversible manner.

Copyright © 2016 Elsevier Inc. All rights reserved.

DOI: 10.1016/j.pep.2016.05.015
PMCID: PMC4947529
PMID: 27241126 [Indexed for MEDLINE]


4. Mol Pharm. 2014 Nov 3;11(11):4238-48. doi: 10.1021/mp500453a. Epub 2014 Oct 6.

Therapeutic impact of erythropoietin-encapsulated liposomes targeted to bone 
marrow on renal anemia.

Miyazaki Y(1), Taguchi K, Sou K, Watanabe H, Ishima Y, Miyakawa T, Mitsuya H, 
Fukagawa M, Otagiri M, Maruyama T.

Author information:
(1)Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, 
Kumamoto University , Kumamoto 862-0973, Japan.

Bone marrow is a key element in the diagnosis of disorders of erythropoiesis, 
including anemia, and a potential target in their treatment. However, because 
efficient delivery of diagnostic and therapeutic agents to bone marrow is 
difficult, such delivery is achieved by administering drugs in large quantities 
that often have adverse effects. Here, we achieved selective delivery of 
recombinant human erythropoietin (rHuEPO) to bone marrow, via its encapsulation 
in liposomes with l-glutamic acid, N-(3-carboxy-1-oxopropyl)-, 1,5-dihexadecyl 
ester (SA) (liposome-EPO). The result, in a rabbit model of renal anemia, was a 
beneficial effect on hematopoiesis, better than with rHuEPO alone. Also, we 
determined that liposome-EPO delivery to bone marrow depended on specific uptake 
by bone marrow macrophages because of the presence of SA. These results indicate 
both that liposome-EPO is a new, promising erythropoietin-stimulating agent and 
that liposomes with SA have potential for diagnostic and therapeutic 
applications in diseases originating from bone marrow.

DOI: 10.1021/mp500453a
PMID: 25255196 [Indexed for MEDLINE]


5. Chem Asian J. 2006 Dec 18;1(6):780-8. doi: 10.1002/asia.200600206.

Asymmetric resolution in ester reduction by NaBH4 at the interface of aqueous 
aggregates of amino acid, peptide, and chiral-counterion-based cationic 
surfactants.

Dasgupta A(1), Mitra RN, Roy S, Das PK.

Author information:
(1)Department of Biological Chemistry, Indian Association for the Cultivation of 
Science, Jadavpur, Kolkata 700032, India.

This study provides insight into the physicochemical aspects of aqueous 
aggregates that comprise amino acid, peptide, and chiral-counterion-based 
cationic surfactants and their correlation with the proficiency of asymmetric 
resolution in ester reduction. The effects of the structural differences in the 
naturally occurring amino acid based and synthetic chiral-counterion-containing 
gemini surfactants on the surface properties as well as on other microstructural 
parameters were studied and correlated to the varied head groups of the 
surfactants. The supramolecular chirality induced from the head-group region of 
chiral amphiphiles in aqueous self-aggregates is evident from circular 
dichroism, scanning electron microscopy, and transmission electron microscopy 
studies. This large-scale chirality at the interface of self-aggregates was 
exploited towards asymmetric resolution in ester reduction by NaBH4. An 
enantiomeric excess of 53% ((R)-2-phenylpropan-1-ol) was found in the case of 
the n-hexyl ester of 2-phenylpropionic acid as substrate in the aqueous 
aggregate of N,N'-dihexadecyl-N,N,N',N'-tetramethyl-N,N'-ethanediyldiammonium 
diquinate. Thus, a simple and environmentally benign pathway for asymmetric 
resolution in ester reduction by sodium borohydride alone is reported, which 
utilizes the varied spatial asymmetry at the interface of aqueous aggregates of 
cationic chiral amphiphiles.

DOI: 10.1002/asia.200600206
PMID: 17441121 [Indexed for MEDLINE]