Phytochemical Screening of Nyctanthes arbor-tristis Plant Extracts and Their Antioxidant and Antibacterial Activity Analysis.

Nyctanthes arbor-tristis, alias "Vishnu Parijat," is a medicinal plant used to treat various inflammation-associated ailments and to combat innumerable infections in the traditional system of medicine. In the present study, we collected the samples of N. arbor-tristis from the lower Himalayan region of Uttarakhand, India, and carried out their molecular identification through DNA barcoding. To examine the antioxidant and antibacterial activities, we prepared the ethanolic and aqueous extracts (from flowers and leaves) and performed their phytochemical analysis by using different qualitative and quantitative approaches. The phytoextracts showed marked antioxidant potential, as revealed by a comprehensive set of assays. The ethanolic leaf extract showed marked antioxidant potential towards DPPH, ABTS, and NO scavenging (IC50 = 30.75 ± 0.006, 30.83 ± 0.002, and 51.23 ± 0.009 µg/mL, respectively). We used TLC-bioautography assay to characterize different antioxidant constituents (based on their Rf values) in the chromatograms ran under different mobile phases. For one of the prominent antioxidant spots in TLC bioautography, GC-MS analysis identified cis-9-hexadecenal and n-hexadecanoic acid as the major constituents. Furthermore, in antibacterial study, the ethanolic leaf extract showed marked activity against Aeromonas salmonicida (113.40 mg/mL of extract was equivalent to 100 µg/mL of kanamycin). In contrast, the ethanolic flower extract showed considerable antibacterial activity against Pseudomonas aeruginosa (125.85 mg/mL of extract ≡100 µg/mL of kanamycin). This study presents the phylogenetic account and unravels the antioxidant-related properties and antibacterial potential of N. arbor-tristis.

A Review of Anti-Cancer and Related Properties of Lichen-Extracts and Metabolites.

BACKGROUND: Lichens are a composite consortium of a fungus and an alga. The symbiotic organisms are naturally equipped with distinct characteristics as compared to constituting organisms separately. Lichens, due to their peculiar anatomy and physiology, are the reservoir of more than 600 unique secondary metabolites, also known as 'lichen substances'. Since ancient times, many ethnic groups from various parts of the world have known about the applications of lichens as major provenance of food/fodder, medicine, dyes, spices, perfumes, etc. Lichen substances have shown impressive antioxidant, antimicrobial, antiviral, anti-tumor, and antiinflammatory activities under experimental conditions. Usnic acid, a well-known metabolite found in several species of lichens, possesses potent antioxidant and anti-inflammatory activities. It also has significant antiproliferative potential, as revealed through testing in different cancer cell lines. Atranorin, Lecanoric acid, Norstictic acid, Lobaric acid, Stictic acid, Ramalin, Gyrophoric acid, Salazinic acid, Protolichesterinic, and Fumarprotocetraric acid are some of the other purified lichen-metabolites with potent anti-cancer activities. OBJECTIVE: This study presents an overview of lichen-derived extracts and compounds showing anti-cancer (or related) properties. METHOD: The review comprehends different studies (in vivo and in vitro) backing up the possibility of lichenextracts and metabolites towards their use as antioxidant, anti-proliferative, anti-inflammatory, and Epithelialmesenchymal transition (EMT) -inhibiting agents. RESULTS: Various studies carried out to date show that lichen-extracts and metabolites have a range of anti-cancer and related properties that include anti-oxidative, anti-inflammatory, anti-proliferative, pro-apoptotic, and the potential of inhibition of cancer-associated EMT that is responsible for drug resistance and metastasis of cancer cells in a substantial proportion of cases. CONCLUSION: Lichens are the repertoire of a plethora of lichen-metabolites with significant anti-cancer potential. However, some of the critical 'anti-cancer related' properties, such as the ability of EMT-inhibition and the potential of induction of apoptosis, are relatively less studied for several lichen compounds. Additionally, many lichen compounds need to be purified at a larger scale to explore their anti-cancer potential.

Highly Effective Dual-Function Near-Infrared (NIR) Photosensitizer for Fluorescence Imaging and Photodynamic Therapy (PDT) of Cancer.

We report herein the synthesis and biological efficacy of near-infrared (NIR), bacteriochlorin analogues: 3-(1'-butyloxy)ethyl-3-deacetyl-bacteriopurpurin-18-N-butylimide methyl ester (3) and the corresponding carboxylic acid 10. In in vitro assays, compared to its methyl ester analogue 3, the corresponding carboxylic acid derivative 10 showed higher photosensitizing efficacy. However, due to drastically different pharmacokinetics in vivo, the PS 3 (HPLC purity >99%) showed higher tumor uptake and long-term tumor cure than 10 (HPLC purity >96.5%) in BALB/c mice bearing Colon 26 tumors. Isomerically pure R- and S- isomers of 3 (3a and 3b, purity by HPLC > 99%) under similar treatment parameters showed identical efficacy in vitro and in vivo. In addition, photosensitizer (PS) 3 showed limited skin phototoxicity and provides an additional advantage over the clinically approved chemically complex hematoporphyrin derivative as well as other porphyrin-based PDT agents, which makes 3 a promising dual-function agent for fluorescence-guided surgery with an option of phototherapy of cancer.

Polyacrylamide-based biocompatible Nanoplatform enhances the tumor uptake, PET/fluorescence imaging and anticancer activity of a chlorophyll analog.

In this report we demonstrate the outstanding advantages of multifunctional nanoplatforms for cancer-imaging and therapy. The non-toxic polyacrylamide (PAA) nanoparticles (size:18-25 nm) formulation drastically changed the pharmacokinetic profile of the ¹²4I- labeled chlorophyll-a derivative (formulated in 10% ethanol in PBS) with a remarkable enhancement in tumor uptake, and significantly reduced uptake in spleen and liver. Among the various nanoformulations investigated, the ¹²4I- labeled photosensitizer (dose: 0.6142 MBq), and the cyanine dye-nanoparticles (CD-NP) conjugate (dose 0.3 µmol/kg) in combination showed great potential for tumor imaging (PET/NIR fluorescence) in BALB/c mice bearing Colon26 tumors. Compared to free non-labeled photosensitizer, the corresponding PAA nanoformulation under similar treatment parameters showed a remarkable enhancement in long-term tumor cure by PDT (photodynamic therapy) and provides an opportunity to develop a single nanoplatform for tumor-imaging (PET/fluorescence) and phototherapy, a practical "See and Treat" approach.

Clinical status of anti-cancer agents derived from marine sources.

The chemical, biological and ecological diversity of the marine ecosystem has contributed immensely in the discovery of extremely potent compounds that have shown potent activities in antitumor, analgesia, antiinflammatory, immunomodulation, allergy, anti-viral etc. The compounds of marine origin are diverse in structural class from simple linear peptides to complex macrocyclic polyethers. The recent advances in the sophisticated instruments for the isolation and characterization of marine natural products and development of high-throughput screening, have substantially increased the rate of discovery of various compounds of biomedical application. Didemnin was the first marine peptide that entered in human clinical trials in US for the treatment of cancer and other compounds such as dolastatin-10, soblidotin, didemnin B, ecteinascidin 743, girolline, aplidine, cryptophycins (also arenastatin A), bryostatin 1, ILX 651, kahalalide F, E7389, discodermolide, ES-285 (spisulosine), HTI-286 (hemiasterlin derivative), squalamine, KRN-7000, vitilevuamide, Laulimalide, Curacin A, diazonamide, peloruside A, eleutherobin, sarcodictyin, thiocoraline, salicylihalimides A, ascididemnin, CGX-1160, CGX-1007dictyodendrins, GTS-21 (aka DMBX), manoalide, IPL-576,092 (aka HMR-4011A) have entered in the clinical trials. This article summarize clinical status and synthetic advances of some of these compounds.