Browsing by Subject "Terpenes"
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Item Biopharmaceutical classification and development of limonene-based self-nanoemulsified capsule dosage form of coenzyme Q10(Texas Tech University, 2004-05) Palamakula, AnithaCoenzyme QIO (CoQ) is a challenging micronutrient for oral formulation due to its low aqueous solubility and bioavailability. The present dissertation deals with a systematic approach to classify CoQ biopharmaceutically according to FDA biopharmaceutical classification system (BCS), and to develop a self-nanoemulsified capsule dosage form (SNCDF) with chiral limonenes. We have hypothesized that the oral bioavailability of CoQ may be enhanced by limonene based SNCDF. In vitro transport studies using Caco-2 cells and solubility studies indicated that CoQ is moderately permeable and has low solubility. However, CoQ exhibits substantial solubility in limonenes. The permeability of CoQ across isolated rat GI segments revealed regional differences with maximum absorption through duodenum. Based on these results, a limonene based self-nanoemulsified formulation of CoQ was prepared and evaluated by in vitro and in vivo methods. Dissolution studies in water have shown CoQ release of > 90% within 5 minutes. Thermal analysis showed no significant change in CoQ endotherm. FT-IR and X-ray diffraction studies revealed the preservation of CoQ structure, indicating no interactions. Particle size, turbidity and zeta potential measurements have indicated that R-(+)-limonene provided superior self-nanoemulsified formulation of CoQ when compared with S-(-)-limonene. A three-factor, three-level optimization design was used to evaluate the effect of critical process variables on the drug release characteristics. Mathematical relationships, contour plots and response surface methodology were employed with constrained optimization to predict levels of factors that provide maximum drug release. The predicted and observed responses were in good agreement. The long term stability of the formulation was ascertained by subjecting to various temperature and humidity conditions for 6 months. The results indicated no significant effect on turbidity, particle size, zeta potential, DSC, FT-IR and total drug release at room temperature. The in vivo performance of CoQ limonene based SNCDF and eutectic based self-nanoemulsified drug delivery systems (SNEDDS) was evaluated by assessing the pharmacokinetic parameters, Tmax, Cmax, and AUC in rats. The oral bioavailability of SNCDF and SNEDDS was found to increase by 650% and 730% respectively when compared with CoQ powder (control). Preliminary assessment in human volunteers indicated increased tendency of rate and extent and metabolism of nanoemulsified preparations as compared to control.Item Differential sensing of hydrophobic analytes with serum albumins(2012-05) Ivy, Michelle Adams; Anslyn, Eric V., 1960-In the last decade, there has been a growing interest in the use of differential sensing for molecular recognition. Inspired by the mammalian olfactory system, differential sensing employs an array of non-selective receptors, which through cross-reactive interactions, create a distinct pattern for each analyte tested. The unique fingerprints obtained for each analyte with differential sensing are studied with statistical analysis techniques, such as principal component analysis and linear discriminant analysis. It was postulated that serum albumin proteins would be applicable to differential sensing schemes due to significant differences in sequence identity between different serum albumin species, and due to the wide range of hydrophobic molecules which are known to bind to these proteins. Consequently, cross-reactive serum albumin arrays were developed, utilizing hydrophobic fluorescent indicators to detect hydrophobic molecules. As such, serum albumin cross-reactive arrays were employed to discriminate subtly different hydrophobic analytes, and mixtures of these analytes, in the form of terpenes and perfumes, plasticizers and plastic explosive mixtures, and glycerides and adipocyte extracts. In this doctoral work, a detailed review of the field of differential sensing, and a thorough study of principal component analysis and linear discriminant analysis in various differential sensing scenarios, are given. These introductory chapters aid in better understanding the methods and techniques applied in later experimental chapters. In chapter 3, serum albumins, a PRODAN indicator, and an additive are shown to discriminate five terpene analytes and terpene doped perfumes. Chapter 4 describes an array with serum albumins, two dansyl fluorophores, and an additive which successfully differentiate the plasticizers found within the plastic explosives C4 and Semtex and simulated C4 and Semtex mixtures. Discrimination of these simulated mixtures was also achieved with this array in the presence of soil contaminants, demonstrating the potential real-world applicability of this sensing ensemble. Finally, chapter 5 details an array consisting of serum albumins, several fluorescent indicators, and a Grubb's olefin metathesis reaction, to differentiate saturated and unsaturated triglycerides, diglycerides, and monoglycerides. Mixtures of glycerides in adipocyte extracts taken from rats with different health states were then successfully discriminated, showing promise for clinical applications in differentiating adipoctyes from pre-diabetic, type 2 diabetic, and non-diabetic individuals.Item Phospholipids and Terpenes Enhance the Absorption of Polyphenolics in a Caco-2 Cell Model(2010-08-30) Cardona Ponce, Jorge 1983-Anthocyanins are the most important class of water-soluble pigments responsible for red to blue colors in various plants. Anthocyanins naturally occur in a broad range of plants and studies have shown associations between fruit consumption and reduction of certain diseases thought to be related to the presence of these and other polyphenolics. However, anthocyanin absorption is fairly poor which hinders their potential to be utilized in the human body. Absorption of anthocyanins extracted from a?a? puree and port wine was assessed. Various combinations of terpenes and phospholipids were added to anthocyanins to modulate and increase their transport within a model system. A?a? and port wine anthocyanins were poorly transported in the absence of phospholipids and terpenes. The addition of terpenes and phospholipids significantly increased the transport of anthocyanins. Additionally, the presence of phospholipids and terpenes did not influence the way anthocyanins degraded over a 40 day period of time at three different temperatures. Transport of anthocyanins was not dependent on dosage since absorption results were similar at both concentrations of anthocyanins tested. Two methods to mix anthocyanins, phospholipids, and terpenes were also assessed (Sonication and French Press). Comparisons illustrated that both technologies created matrices that maintained the properties of phospholipids and terpenes as transport enhancers. Finally, a study to determine the efficacy of phospholipids and terpenes on a different type of polyphenolic compound was assessed. Transport of gallic acid was enhanced by the use of these agents that cemented the idea that phospholipids and terpenes can enhance the transport of various types of polyphenolics. The aiding effect of phospholipids and terpenes was well established and could play an important role in future investigation in this field. Further research needs to be conducted to reveal more information about the nature of these vesicles or associations that phospholipids and terpenes may have with anthocyanins. In vivo studies need to be considered to confirm these effects in rat models and, ideally, in humans. Nevertheless, these findings open a new line of investigation that could harvest promising results for the future of ingredient development for food products.Item Stereospecific Synthesis of Tetrahydroarbiglovin(Texas Tech University, 1972-08) McGaughey, Stephen MNot Available.Item Synthesis of some acorane-type sesquiterpenes(Texas Tech University, 1973-12) Norman, Reid L.Not availableItem Total synthesis of anhydro-[beta]-rotundol(Texas Tech University, 1984-08) Bih, Qoang-rungNot available