Supramolecular Pharmaceutical Sciences: A Novel Concept Combining Pharmaceutical Sciences and Supramolecular Chemistry with a Focus on Cyclodextrin-Based Supermolecules

Supramolecular chemistry is an extremely useful and important domain for understanding pharmaceutical sciences because various physiological reactions and drug activities are based on supramolecular chemistry. However, it is not a major domain in the pharmaceutical field. In this review, we propose a new concept in pharmaceutical sciences termed "supramolecular pharmaceutical sciences," which combines pharmaceutical sciences and supramolecular chemistry. This concept could be useful for developing new ideas, methods, hypotheses, strategies, materials, and mechanisms in pharmaceutical sciences. Herein, we focus on cyclodextrin (CyD)-based supermolecules, because CyDs have been used not only as pharmaceutical excipients or active pharmaceutical ingredients but also as components of supermolecules.

Improvement of Pharmaceutical Properties of Isoprenoid Compounds through the Formation of Cyclodextrin Pseudorotaxane-Like Supramolecules

The purpose of this study was to design cyclodextrin (CyD)-based pseudorotaxane-like supramolecular complexes with various isoprenoid compounds, such as reduced coenzyme Q10 (R-CoQ10), squalene, tocotrienol, and teprenone, and to evaluate their pharmaceutical properties. Squalene, tocotrienol, and teprenone formed precipitates with β-CyD and γ-CyD in aqueous solution, whereas R-CoQ10 formed precipitates with γ-CyD aqueous solution. The results of powder X-ray diffraction and (1)H-NMR analyses indicated that these precipitates are derived from pseudorotaxane-like supramolecular complexes. The photostability of teprenone was markedly improved by complexation with CyDs, especially in the γ-CyD system. In addition, the dispersion rates of teprenone in the γ-CyD system were higher than those in the β-CyD system, compared with the corresponding physical mixtures. In conclusion, pharmaceutical properties such as photostability and dispersion rates of isoprenoid compounds were improved by the formation of pseudorotaxane-like supramolecular complexes with β-CyD and/or γ-CyD.

Preparation and evaluation of cyclodextrin polypseudorotaxane with PEGylated liposome as a sustained release drug carrier

Cyclodextrins (CDs) can form polypseudorotaxanes (PPRXs) with drugs or drug carriers possessing linear polymers such as polyethylene glycol (PEG). On the other hand, PEGylated liposomes have been utilized as a representative anticancer drug carrier. However, little is known about the formation of CD PPRX with PEGylated liposome. In the present study, we first report the formation of CD PPRX with PEGylated liposome and evaluate it as a sustained release drug carrier. PEGylated liposome encapsulating doxorubicin was disrupted by the addition of α-CD. Meanwhile, γ-CD included two PEG chains and/or one bending PEG chain of PEGylated liposome and formed PPRX without the disruption of the membrane integrity of the PEGylated liposome. Moreover, the release of doxorubicin and/or PEGylated liposome encapsulating doxorubicin from the PPRX was prolonged in accordance with the matrix type release mechanism. These findings suggest the potential of γ-CD PPRX as sustained release carriers for PEGylated liposome products.

Enhanced water dispersibility of coenzyme Q10 by complexation with albumin hydrolysate

The biologically important coenzyme Q10 (CoQ10) is widely used as a drug for chronic heart failure, as a nutritional supplement, and in cosmetics. However, the oral bioavailability of CoQ10 is poor due to its extremely low solubility in aqueous media. In this study, complexation of CoQ10 with albumin hydrolysate as a peptide mixture (Pep) was shown to enhance the water dispersibility of CoQ10. An aqueous solution of Pep and an acetone solution of CoQ10 were mixed and lyophilized to obtain a white-yellow powder containing peptides and CoQ10 complex (Q10-Pep). The water dispersibility of Q10-Pep was much higher than that of CoQ10 alone and increased with the quantity of Pep. The particle size of Q10-Pep in aqueous media was 170-280 nm, suggesting that Q10-Pep was present as a hydrocolloidal material. Characterization of Q10-Pep using differential scanning calorimetry showed that CoQ10 was incorporated in the hydrocolloid in an amorphous state.

Industrial applications of alkaliphiles and their enzymes--past, present and future

Alkaliphiles are microorganisms that can grow in alkaline environments, i.e. pH >9.0. Their enzymes, especially extracellular enzymes, are able to function in their catalytic activities under high alkaline pH values because of their stability under these conditions. Proteases, protein degrading enzymes, are one of the most produced enzymes in industry. Among proteases, alkaline proteases, which are added to some detergents, are the most produced. Other alkaline enzymes, e.g. alkaline cellulases, alkaline amylases, and alkaline lipases, are also adjuncts to detergents for improving cleaning efficiency. Alkaline enzymes often show activities in a broad pH range, thermostability, and tolerance to oxidants compared to neutral enzymes. Alkaliphilic Bacillus species are the most characterized organisms among alkaliphiles. They produce so many extracellular alkaline-adapted enzymes that they are often good sources for industrial enzymes. As a patent strain, the whole genome sequence of alkaliphilic Bacillus halodurans C-125 has been sequenced for the first time. In addition, an increasing number of whole genomic sequences and structural analyses of proteins in alkaliphiles, development of genetic engineering techniques and physiological analyses will reveal the alkaline adaptation mechanisms of alkaliphilic Bacillus species and the structural basis of their enzymatic functions. This information opens up the possibility of new applications. In this paper we describe, first, the physiologies of environmental adaptations, and then the applications of enzymes and microorganisms themselves in alkaliphilic Bacillus species.