Search

Cosmetic products and their use are an integral part of daily life. People are well aware of the benefits as well as harmful effects associated with the use of synthetic cosmetic products. Therefore, in recent times there has been manifold increased demand for naturally derived cosmetic products, blended with pharmaceutical properties (cosmeceuticals). Traditional approaches for isolation and identification of cosmeceutical compounds using in vitro or two-dimensional (2D) cell-based assays are tedious, time-consuming, and most of the time lack clinical efficacy. As an alternative to 2D cell culture-based approaches for drug discovery, the last decade has witnessed the development of three-dimensional (3D) cell culture-based techniques using various commercially available 3D reconstructed human skin (RHS) models and their different applications in the field of cosmeceutical research. The 3D RHS models exactly mimic the natural human skin, resulting in fascinating drug discoveries from natural resources. This chapter summarizes the application of 3D RHS models for the screening of compounds for their cosmeceutical potential such as skin whitening, antiaging, antiinflammatory, antioxidant, anticancer, skin penetration, skin absorption, skin irritation, phototoxic, and skin wound healing.

A huge quantity of seafood waste is generated from seafood restaurants, fish-processing industries, fish markets, and kitchens every day. The disposal of fish wastes in marine and fresh waters gives rise to an increasing environmental pollution thus adversely affecting the health of aquatic biota. In the present study, nine marine seaweed (Ulva sp.)-associated bacteria capable of calcium carbonate solubilization were isolated from the rocky intertidal region of Anjuna Beach, Goa, India. Out of these nine bacterial isolates, only three were found to utilize 1% crab shell/fish scales/prawn shell powder as a sole source of carbon and nitrogen in seawater-based agar after 10 days. These three bacterial isolates were chosen for further investigation and were designated as PM1, PM6, and PM9. Selected bacterial isolates were found to possess phosphate solubilization, cellulase, protease, and chitinase activity. They didn't show cross-inhibition against each other and therefore were used as bacterial consortia for seafood waste degradation study. Consortia showed significant degradation of crab shells, prawn shells, and fish scales within 4 days in the seawater-based broth, which was confirmed by DNSA method. DNSA method demonstrated 310 ± 8μg/mL, 245 ± 14 μg/mL, and 180 ± 15 μg/mL reducing sugars released during degradation of crab shell, prawn shell, and fish scales, respectively, which is considerably high. Based on morphology and biochemical tests, bacterial isolates PM1, PM6, and PM9 were identified as Bacillus sp., Brevibacterium sp. and Vibrio sp., respectively, and through 16S rRNA sequencing, bacterial isolate PM6 was further confirmed to be Brevibacterium iodinum (accession number MG971400). Seaweed-associated bacterial isolates as consortia can, therefore, be employed for biodegradation of seafood wastes. Sugars released during bacterial degradation of seafood waste can be utilized for ethanol fermentation using Saccharomyces cerevisiae.

A synthetic flavone derivative 2-(benzo[d][1,3]dioxol-5-yl)-4H-chromen-4-one (BDC) was synthesized by the one pot reaction method and assessed for α-glucosidase inhibitory activity. The BDC demonstrated dose dependent inhibition of α-glucosidase activity. A maximum inhibition (99.3 ± 0.26%) of α-glucosidase was observed at 27.6 µM. The maximum α-glucosidase inhibitory activity depicted by BDC 27.6 µM concentration was 22.4 fold over the maximum inhibition observed with acarbose (97.72 ± 0.59% at 669.57 µM), a standard commercial anti-diabetic drug. In contrast to acarbose that depicted competitive type inhibition, kinetic studies of α-glucosidase inhibition by BDC demonstrated non-competitive inhibition with Km of 0.71 mM−1 and a Vmax of 0.028 mmol/min. In silico studies suggest allosteric interaction of BDC with α-glucosidase at a minimum binding energy (ΔG) of −8.64 kcal/mol and Ki of 465.3 nM, whereas, acarbose interacted at the active site of α-glucosidase with ΔG of −9.23 kcal/mol and Ki of 172 nM. Thus BDC significantly inhibited α-glucosidase in comparison to acarbose. Moreover, BDC has been endorsed for drug likeness by evaluating it as per Lipinski rule of five. Thus, BDC can be a lead compound for the management of type-2 diabetes mellitus.

Pristine and 2 % silver-doped indium oxide (In2O3) nanoparticles, synthesized by solution combustion method, yielded spherical nanoparticles in the range of 20–30 nm. The nanoparticles were stabilized in cubic bixbyite structure as revealed from X-ray diffraction study. In order to evaluate the potential of these nanoparticles to modulate enzyme activity, α-amylase and α-glucosidase were used as model enzymes. Pristine and 2 % silver-doped In2O3 nanoparticles demonstrated dose-dependent inhibition of α-amylase and α-glucosidase activities. Pristine In2O3 nanoparticles demonstrated 26.4 % (300 µg/mL) and 65.3 % (300 µg/mL) inhibition against α-amylase and α-glucosidase, respectively. In contrast, silver-doped In2O3 nanoparticles depicted 94.1 % (300 µg/mL) and 99.6 % (0.18 µg/mL) inhibition against α-amylase and α-glucosidase, respectively. In comparison with acarbose, a standard anti-diabetic drug that depicted absolute inhibition of α-glucosidase activity at 300 µg/mL, 2 % silver-doped In2O3 nanoparticles completely inhibited α-glucosidase at a very low concentration (0.18 µg/mL). In view of our results, the activity of α-amylase and α-glucosidase, which are targets for treatment of type 2 diabetes, can be modulated using silver-doped In2O3 nanoparticles in the concentration-dependent manner. Therefore, silver-doped In2O3 has a potential to be used as a prospective starch blocker.

Grewia nervosa is a herbal plant used in traditional medicine for different purposes. Bioassay-guided chemical fractionation of G. nervosa roots resulted in an identification of two known and one new compound, namely microgrewiapine A, homomicrogrewiapine, and N-methylmicrocosamine, respectively. Their structures were determined using combination of LC/HR-MS, 1 H-NMR, and IR spectral analyses and followed by comparison with those reported in the literature. The problematic separation of these alkaloids on traditional column chromatography (Silica gel, Octadecyl silane, Sephadex) was resolved by using HPLC. Structurally similar compounds from the piperidine family have been characterized by using HR-MS analysis in combination with NMR data of crude samples. The major constituent i.e. N-methylmicrocosamine isolated from the butanol fraction of methanol root extract (MRE) was found to possess the dose dependent α-glucosidase inhibition activity with an IC50 value of 53.40 μm. Furthermore, N-methylmicrocosamine showed maximum α-glucosidase inhibition of 97.48 ± 0.7% at 107.5 μm, which is approximately 1.3 × 103 fold higher than the activity shown by acarbose (97.72% inhibition at 61.95 mm), a standard anti-diabetic drug available commercially. This work also reports the in vitro α-glucosidase inhibitory activity of the major alkaloids isolated from G. nervosa for the first time.

The title compounds (IV) are obtained by a solvent-free three-component condensation reaction between various aromatic aldehydes, ethyl acetoacetate, and urea/thiourea.

A solvent free three component condensation reaction between an aldehyde, ethyl acetoacetate and urea catalyzed by graphite, a green catalyst is described for the synthesis of dihydropyrimidin-2(1H)-ones. This protocol is scalable and the catalyst is reusable. This method is also applied for the synthesis of dihydropyrimidin-2(1H)-thiones. α-Amylase, a key enzyme in carbohydrate metabolism is generally targeted for management of type 2 diabetes. The therapeutic potential of the dihydropyrimidinones and dihydropyrimidinthiones to inhibit α-amylase activity was evaluated by in vitro assay. Of the synthesized compounds 3,4-dihydropyrimidin-2(1H)-thione (1k) demonstrated highest inhibition of α-amylase activity.