Development of Genome-Wide Functional Markers Using Draft Genome Assembly of Guava (Psidium guajava L.) cv. Allahabad Safeda to Expedite Molecular Breeding.

Guava (Psidium guajava L.), a rich source of nutrients, is an important tropical and subtropical fruit of the Myrtaceae family and exhibits magnificent diversity. Genetic diversity analysis is the first step toward the identification of parents for hybridization, genetic mapping, and molecular breeding in any crop species. A diversity analysis based on whole-genome functional markers increases the chances of identifying genetic associations with agronomically important traits. Therefore, here, we sequenced the genome of guava cv. Allahabad Safeda on an Illumina platform and generated a draft assembly of ~304 MB. The assembly of the Allahabad Safeda genome constituted >37.95% repeat sequences, gene prediction with RNA-seq data as evidence identified 14,115 genes, and BLAST n/r, Interproscan, PfamScan, BLAST2GO, and KEGG annotated 13,957 genes. A comparative protein transcript analysis of tree species revealed the close relatedness of guava with Eucalyptus. Comparative transcriptomics-based SSR/InDel/SNP-PCR ready genome-wide markers in greenish-yellow skinned and white fleshed-Allahabad Safeda to four contrasting cultivars viz apple-color-skinned and white-fleshed-Lalima, greenish-yellow-skinned and pink-fleshed-Punjab Pink, purple-black-skinned and purple-fleshed-Purple Local and widely used rootstock-Lucknow-49 were developed. The molecular markers developed here revealed a high level of individual heterozygosity within genotypes in 22 phenotypically diverse guava cultivars. Principal coordinate, STRUCTURE clustering, and neighbor-joining-based genetic diversity analysis identified distinct clusters associated with fruit skin and flesh color. The genome sequencing of guava, functional annotation, comparative transcriptomics-based genome-wide markers, and genetic diversity analysis will expand the knowledge of genomes of climacteric fruits, facilitating trait-based molecular breeding and diversifying the nutritional basket.

Understanding pharmaceutical polymorphic transformations I: influence of process variables and storage conditions.

The active pharmaceutical ingredient (API) of a dosage form is affected by number of mechanical and environmental factors which have a tendency to alter its crystalline state. Polymorphic transitions have been observed to occur during various unit operations like granulation, milling and compression. Forces of pressure, shear and temperature have an ability to induce alterations in crystal habit. A conversion in polymorphic form during a unit operation is very likely to affect the handling of API in the subsequent unit operation. Transitions have also been observed during storage of formulations where the relative humidity and temperature play a major role. An increase in temperature during storage can dehydrate or desolvate the crystal and hence produce crystal defects, whilst, high humidity conditions produce higher molecular mobility leading to either crystallization of API or alteration of its crystalline form.

A critical appraisal of microemulsions for drug delivery: part II.

Microemulsions are thermodynamically stable, optically transparent isotropic solutions of oil and water successfully formulated by using a combination of suitable surfactant and cosurfactant. The solubilization power of microemulsions for lipophilic, hydrophilic and amphiphilic solutes form a viable approach for enhancing the bioavailability of hydrophobic drugs and percutaneous permeation of poorly permeable drugs, mainly due to the large area per volume ratio available for mass transfer. Microemulsions have emerged as novel vehicles for drug delivery due to their versatile applications. They allow sustained release for topical, oral, nasal, intravenous, ocular, parenteral and other administration routes of drugs. They also offer a relevant application platform for improving target specificity, therapeutic activity, and reducing toxicity of drugs.

A critical appraisal of microemulsions for drug delivery: part I.

Microemulsions (MEs) are thermodynamically stable, optically transparent isotropic solutions of oil and water successfully formulated by using a combination of suitable surfactant and cosurfactant. While the selection of oil is based primarily on the solubility of drug in it, surfactant is generally selected on the basis of its hydrophilic-lipophilic balance value. MEs are characterized by ultra-low interfacial tension between the immiscible phases and offer the advantage of spontaneous formation, thermodynamic stability and ease of manufacture. The solubilization power of MEs for lipophilic, hydrophilic and amphiphilic solutes form a viable approach for enhancing bioavailability of hydrophobic drugs and percutaneous permeation of poorly permeable drugs, mainly due to the large area to volume ratio available for mass transfer.

Aegle marmelos fruit pectin for food and pharmaceuticals: Physico-chemical, rheological and functional performance.

Pectin is used in a number of foods as a gelling agent, thickener, texturizer, emulsifier and stabilizer. Bael fruit, obtained from Aegle marmelos, is a rich source of pectin. Bael fruit pectin (BFP) was extracted from ripe Bael fruits. The process yielded 15% (w/w) pure BFP. The swelling index decreased in the following order: water>pH 7.4>pH 6.8>pH 1.2>HCl (0.1N). Galacturonic acid content of 87.8%, degree of esterification of 47.2%, 17.3% methoxy groups, 0.29% acetyl groups and equivalent weight of 1209.5, indicate it to be a good gelling agent and easily amenable to derivatization. BFP exhibited a significant concentration-dependent prolongation of prothrombin time. The absence of hemagglutinating activity and antinutritional factors coupled with the activity to confer better emulsion capacity, stability and antimicrobial activity gives BFP a clear edge over commercial citrus pectin (CP) for exploitation as an additive in food and pharmaceuticals.

Sulfation of Aegle marmelos gum: synthesis, physico-chemical and functional characterization.

The present investigation was aimed at optimizing the conditions for preparing sulfated derivative of gum obtained from partially ripe fruits of Aegle marmelos. Elemental analysis, FTIR-ATR and NMR studies confirmed successful sulfation. The ratio of chlorosulfonic acid to pyridine exerted maximum influence on the degree of substitution followed by reaction temperature and reaction time. The sulfated derivative showed higher swelling in both acidic and alkaline pH as compared to unmodified gum. It also possessed higher negative zeta potential, higher viscosity, work of shear, firmness, consistency, cohesiveness and index of viscosity as compared to both unmodified gum as well as sodium alginate. Sulfated derivative was superior to unmodified gum and sodium alginate in terms of antimicrobial and anticoagulant activity. The sulfated sample appears to be a potential substitute over the unmodified gum sample and sodium alginate for modulating physicochemical properties of food and drug release dosage forms.

An insight into the properties of Aegle marmelos pectin-chitosan cross-linked films.

Pectin of Aegle marmelos (AP) ripe fruits processed in equal proportion with chitosan (CH) formed films that exhibited minimum swelling index and volume index on exposure to buffers of acidic and alkaline pH. Highest contact angle and spreading coefficient coupled with lowest work of adhesion in all buffers for this film suggested availability of limited number of functional groups for interaction with water molecules due to optimum cross-linking between -NH(3)(+) groups of CH and -COO(-) groups of AP. This contention was substantiated by the presence of almost negligible charge on this film. The endothermic transition ΔH characteristic of -NH(3)(+)-COO(-) cross-linking between groups in this film was observed to decrease by only 1% after its sequential exposure to pH 1.2 (3 h) and pH 7.4 (6 h). Furthermore, the absence of pores or erosion in the scanning electron photomicrograph suggested the versatility of this film due to its resistance to acidic and alkaline pH.

Tight junctions in skin: new perspectives.

Tight junctions (TJs) are intercellular contacts that seal the space between the individual cells of an epithelial sheet or stratifying epithelia, such as the epidermis, so that they can collectively separate tissue compartments. Intercellular junctions, such as adherens and TJs, play a crucial role in the formation and maintenance of epithelial and endothelial barriers. A variety of components including claudins, occludin, tricellulin, zonula occluden proteins and junctional adhesion molecules have been identified in complex localization patterns in mammalian epidermis. In several skin diseases that are characterized by impaired skin barrier function, altered proliferation/differentiation of the epidermis and/or infiltration of inflammatory cells, altered expression patterns of TJ proteins have been observed. This review is aimed at providing an insight into the molecular composition, tools for identification and understanding the role of TJs in skin diseases and barrier function regulation.