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Aim: Rhodiola imbricata is an endangered medicinal plant of the trans-Himalayan Leh-Ladakh region belonging to the family Crassulaceae. An efficient propagation and regeneration system via direct shoot organogenesis from leaf explant and evaluation of cinnamyl alcohol (Secondary metabolite) was established in this study. Material and Methods: In vitro grown leaves were inoculated using Murashige and Skoog (MS) medium supplemented with (alpha)- naphtalene acetic acid (NAA) in combination with 6- benzyladenine (BAP) for callus proliferation and regeneration. Results: The highest percentage of rhizogenous callus was induced in medium containing NAA (10.0-15.0 μM). The highest percentage of shoot formation from leaf derived callus was obtained in the medium containing of NAA (5.0 μM) and BAP (2.5 μM) as well as in NAA (1.0 μM), BAP (5.0 μM) (38.88% and 37.49%) respectively. Rooting of regenerated shoots were effective when a lower concentration of NAA (0.5 μM) was used alone. A maximum number of roots (22.0) and higher length (0.6 cm) was observed. The in-vitro plantlets with well-developed shoots and roots were acclimatized successfully to natural field conditions with a survival rate of over 80%. Cinnamyl alcohol (Secondary metabolite) evaluation was also done for the very first time and an upregulation of 49.6% and 30.6% were observed in in-vitro roots and shoots when compared with mother root and shoot respectively. Hence, it was proved that the content of secondary metabolites obtained from in-vitro raised plants is higher than mother plant. Conclusion : These results may lay a foundation for genetic improvement and can be used to determine sequential level of targeted secondary metabolites through cell culture in Rhodiola imbricata. [ABSTRACT FROM AUTHOR]

Synthetic manifestations of supramolecular chirality have extensively drawn inspiration from naturally occurring systems. Even though in biological systems conformational changes are dissipative, synthetic systems that change conformation under non-equilibrium conditions have still not been established. Herein, we attempt to alleviate this scenario by reporting a synthetic supramolecular system that undergoes temporal changes in its helical conformation as an active system at the expense of a biologically relevant chemical fuel, ATP. Use of enzymes working in tandem provides transient and switchable helices with modular lifetime and stereomutation rates. [ABSTRACT FROM AUTHOR]

Fullerenes are the allotropic form of carbon consisting of a cage-like structure due to which they have attained special attention from researchers since their discovery in 1985. The unique chemical and physical properties of fullerene have attracted researchers to develop a variety of its biomedical applications. The closed cage structure of fullerenes can be used for various drug delivery applications and can also act as a medium for controlled release formulations. The development of targeted anticancer drug and drug delivery systems is one of the most challenging fields, which is widely studied and researched. In this review, we aim to provide a comprehensive review on the most recent advances in fullerenes as targeted anticancer drug delivery systems along with their therapeutic applications and challenges, thus serving the pharmaceutical and biotechnology community., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Camptothecin is a naturally occurring alkaloid obtained from the stem wood of the Chinese tree, Camptotheca acuminata. It exerts pharmacological effects due to its ability to selectively inhibit the type-I topoisomerase DNA nuclear enzyme. Several semisynthetic analogs of camptothecin have been synthesized to date possessing antitumor activity., Objective: Camptothecin (CPT) is one of the most promising anticancer drugs but it produces various side effects because of its non-selectivity towards cancer cells. To overcome these adverse effects, we synthesized biotin conjugate of camptothecin, which was linked via a self-immolative disulfide linker (CPT-SS-Biotin)., Methods: Biotin conjugated camptothecin linked through a disulfide bond was synthesized following schemes, and the structural characterization was carried out. The stability and drug release studies were performed in the presence of glutathione (GSH) while in vitro studies were performed on 4T1 tumor cell lines. In vivo pharmacological investigation was done using an antitumor Wistar rat model., Results: The stability and drug release studies were performed in the presence of glutathione (GSH), and CPT-SSBiotin was found to be physiologically stable moiety and can only be cleaved in the presence of GSH to release free CPT. The CPT-SS-Biotin showed higher toxicity in the biotin-overexpressing 4T1 tumor cell line with a lower IC50 value (8.44 μM) compared to camptothecin alone (IC 50 > 30 μM). CPT-SS-Biotin also showed 10.6% higher cellular uptake by cells in comparison to free camptothecin. The CPT-SS-Biotin was delivered to cells by binding to the biotin receptors on the cell surface, followed by energy-dependent endocytosis and internalization to cause cellular toxicity., Conclusion: In-vivo tumor suppression studies and in vitro cell line studies along with serological parameters and histopathological studies showed that conjugate produced a high therapeutic effect and remarkably reduced toxic effects in comparison to free CPT. The results suggested that biotinylation of camptothecin via disulfide linker can be a safe and efficacious method in cancer therapeutics., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The characterization of newly synthesized materials is a cornerstone of all chemistry and nanotechnology laboratories. For this purpose, a wide array of analytical techniques have been standardized and are used routinely by laboratories across the globe. With these methods we can understand the structure, dynamics and function of novel molecular architectures and their relations with the desired performance, guiding the development of the next generation of materials. Moreover, one of the challenges in materials chemistry is the lack of reproducibility due to improper publishing of the sample preparation protocol. In this context, the recent adoption of the reporting standard MIRIBEL (Minimum Information Reporting in Bio-Nano Experimental Literature) for material characterization and details of experimental protocols aims to provide complete, reproducible and reliable sample preparation for the scientific community. Thus, MIRIBEL should be immediately adopted in publications by scientific journals to overcome this challenge. Besides current standard spectroscopy and microscopy techniques, there is a constant development of novel technologies that aim to help chemists unveil the structure of complex materials. Among them super-resolution microscopy (SRM), an optical technique that bypasses the diffraction limit of light, has facilitated the study of synthetic materials with multicolor ability and minimal invasiveness at nanometric resolution. Although still in its infancy, the potential of SRM to unveil the structure, dynamics and function of complex synthetic architectures has been highlighted in pioneering reports during the last few years. Currently, SRM is a sophisticated technique with many challenges in sample preparation, data analysis, environmental control and automation, and moreover the instrumentation is still expensive. Therefore, SRM is currently limited to expert users and is not implemented in characterization routines. This perspective discusses the potential of SRM to transition from a niche technique to a standard routine method for material characterization. We propose a roadmap for the necessary developments required for this purpose based on a collaborative effort from scientists and engineers across disciplines., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Chirality-driven self-sorting is envisaged to efficiently control functional properties in supramolecular materials. However, the challenge arises because of a lack of analytical methods to directly monitor the enantioselectivity of the resulting supramolecular assemblies. Presented herein are two fluorescent core-substituted naphthalene-diimide-based donor and acceptor molecules with minimal structural mismatch and they comprise strong self-recognizing chiral motifs to determine the self-sorting process. As a consequence, stereoselective supramolecular polymerization with an unprecedented chirality control over energy transfer has been achieved. This chirality-controlled energy transfer has been further exploited as an efficient probe to visualize microscopically the chirality driven self-sorting., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)