Alkaloids and aromatics of Cyathobasis fruticulosa (Bunge) Aellen

Four undescribed coumarin derivatives, with ten amides from the roots of Ficus hirta and their cytotoxic activities

Four undescribed coumarin derivatives, ficusalt A (1) and ficusalt B (2), a pair of racemic coumarins, (±) ficudimer A (3a/3b), along with ten known amides, were isolated from the roots of Ficus hirta. Their structures were elucidated by several spectroscopic data analyses, including HRESIMS, NMR, and X-ray single-crystal diffraction. The cytotoxic activities of all compounds against HeLa, HepG2, MCF-7, and H460 cell lines were detected using the MTT assay. Among these, 5 showed the highest activity against HeLa cells. Subsequently, the apoptotic, anti-invasive, and anti-migration effects of 5 on HeLa cells were determined by flow cytometer, transwell invasion assay, and wound-healing assay, respectively. The result suggested that 5 distinctly induced the apoptosis in HeLa cells and inhibited their invasion and migration. Further studies on anticancer mechanisms were conducted using Western blotting. As a result, 5 increased the cleavage of PARP and the expression of pro-apoptotic protein Bax. Moreover, 5 notably upregulated the phosphorylation of p38 and JNK, whereas inhibited the expression of p-ERK and p-AKT. Our results demonstrated that 5 could be a potential leading compound for further application in the treatment of cervical cancer.

Alkaloid constituents from the fruits of Flueggea virosa

Three new indole alkaloids, flueindolines A-C (1-3), along with nine known alkaloids (4-12), were isolated from the fruits of Flueggea virosa (Roxb. ex Willd.) Voigt. Compounds 1 and 2 are two new fused tricyclic indole alkaloids possessing an unusual pyrido[1, 2-a]indole framework, and 3 presents a rare spiro (pyrrolizidinyl-oxindole) backbone. Their structures with absolute configurations were elucidated by means of comprehensive spectroscopic analysis, chemical calculation, as well as X-ray crystallography. Chiral resolution and absolute configuration determination of the known compounds 4, 10, and 11 were reported for the first time. The hypothetical biogenetical pathways of 1-3 were herein also proposed.

Natural Products as Fungicide and Their Role in Crop Protection

Seeking solutions from nature for solving one and all problems is the age-old practice for mankind, and natural products are proved to be the most effective one for keeping up the balance of development as well as the “healthy, wealthy, and well” condition of mother nature. Fungal pathogens are proved to be a common and popular contaminant of agroecosystem that approximately causes 70–80% of total microbial crop loss. To meet the proper global increasing need of food products as a result of population explosion, managing agricultural system in an eco-friendly and profitable manner is the prime target; thus the word “sustainable agriculture” plays it part, and this package is highly effective when coupled with nature-derived fungicidal products that can minimize the event of fungal infections in agrarian ecosystem. Present study enlists the most common and effective natural products that might be of plant or microbial origin, their mode of action, day-by-day development of phytopathogenic resistance against the prevailing fungicides, and also their role in maintenance of sustainability of agricultural practices with special emphasis on their acceptance over the synthetic or chemical one. A large number of bioactive compounds ranging from direct plant (both cryptogams algae and moss and phanerogams)-derived natural extracts, essential oil of aromatic plants, and low-molecular-weight antimicrobial compounds known as phytoalexins to secondary metabolites that are both volatile and nonvolatile organic compounds of microbes (fungal and actinobacterial members) residing inside the host tissue, called endophyte, are widely used as agricultural bioweapons. The rhizospheric partners of plant, mycorrhizae, are also a prime agent of this chemical warfare and protect their green partners from fungal invaders and emphasize the concept of “sustainable agriculture.”

The Biological Activity of Natural Alkaloids against Herbivores, Cancerous Cells and Pathogens

The growing incidence of microorganisms that resist antimicrobials is a constant concern for the scientific community, while the development of new antimicrobials from new chemical entities has become more and more expensive, time-consuming, and exacerbated by emerging drug-resistant strains. In this regard, many scientists are conducting research on plants aiming to discover possible antimicrobial compounds. The secondary metabolites contained in plants are a source of chemical entities having pharmacological activities and intended to be used for the treatment of different diseases. These chemical entities have the potential to be used as an effective antioxidant, antimutagenic, anticarcinogenic and antimicrobial agents. Among these pharmacologically active entities are the alkaloids which are classified into a number of classes, including pyrrolizidines, pyrrolidines, quinolizidines, indoles, tropanes, piperidines, purines, imidazoles, and isoquinolines. Alkaloids that have antioxidant properties are capable of preventing a variety of degenerative diseases through capturing free radicals, or through binding to catalysts involved indifferent oxidation processes occurring within the human body. Furthermore, these entities are capable of inhibiting the activity of bacteria, fungi, protozoan and etc. The unique properties of these secondary metabolites are the main reason for their utilization by the pharmaceutical companies for the treatment of different diseases. Generally, these alkaloids are extracted from plants, animals and fungi. Penicillin is the most famous natural drug discovery deriving from fungus. Similarly, marines have been used as a source for thousands of bioactive marine natural products. In this review, we cover the medical use of natural alkaloids isolated from a variety of plants and utilized by humans as antibacterial, antiviral, antifungal and anticancer agents. An example for such alkaloids is berberine, an isoquinoline alkaloid, found in roots and stem-bark of Berberis asculin P. Renault plant and used to kill a variety of microorganisms.

Pd/Cu Cocatalyzed Oxidative Tandem C-H Aminocarbonylation and Dehydrogenation of Tryptamines: Synthesis of Carbolinones

The Pd/Cu cocatalyzed oxidative tandem C-H aminocarbonylation and dehydrogenation was developed, affording carbolinones with molecular oxygen as the terminal oxidant. Natural product strychnocarpine and its derivatives were prepared conveniently using this strategy.

Synthetic analogs of stryphnusin isolated from the marine sponge Stryphnus fortis inhibit acetylcholinesterase with no effect on muscle function or neuromuscular transmission

The current study describes the AChE inhibitory effect of natural marine neuroactive compounds.

Biochemical Evaluation of Phenylalanine Ammonia Lyase from Endemic Plant Cyathobasis fruticulosa (Bunge) Aellen. for the Dietary Treatment of Phenylketonuria

Enzyme substitution therapy with the phenylalanine ammonia lyase (PAL) is a new approach to the treatment of patients with phenylketonuria (PKU). This enzyme is responsible for the conversion of phenylalanine to trans-cinnamic acid. We assessed the PAL enzyme of the endemic plant Cyathobasis fruticulosa (Bunge) Aellen. for its possible role in the dietary treatment of PKU. The enzyme was found to have a high activity of (64.9±0.1) U/mg, with the optimum pH, temperature and buffer (Tris-HCl and l-phenylalanine) concentration levels of pH=8.8, 37 °C and 100 mM, respectively. Optimum enzyme activity was achieved at pH=4.0 and 7.5, corresponding to pH levels of gastric and intestinal juice, and NaCl concentration of 200 mM. The purification of the enzyme by 1.87-fold yielded an activity of 98.6 U/mg. PAL activities determined by HPLC analyses before and after purification were similar. Two protein bands, one at 70 and the other at 23 kDa, were determined by Western blot analysis of the enzyme. This enzyme is a potential candidate for serial production of dietary food and biotechnological products.

Elicitation studies in cell suspension cultures of Cannabis sativa L

Cannabis sativa L. plants produce a diverse array of secondary metabolites. Cannabis cell cultures were treated with biotic and abiotic elicitors to evaluate their effect on secondary metabolism. Metabolic profiles analysed by (1)H NMR spectroscopy and principal component analysis (PCA) showed variations in some of the metabolite pools. However, no cannabinoids were found in either control or elicited cannabis cell cultures. Tetrahydrocannabinolic acid (THCA) synthase gene expression was monitored during a time course. Results suggest that other components in the signaling pathway can be controlling the cannabinoid pathway.

Antimicrobial Evaluation of Clerodane Diterpenes from Polyalthia Longifolia Var. Pendula

Phytochemical investigation of the ethanolic extract of leaves of Polyalthia longifolia var. pendula has led to the isolation of seven clerodane diterpenoids and five alkaloids. (-)-14, 15-bisnor-3, 11 E-kolavadien-13-one (1), (-)-16-oxocleroda-3,13(14) E-dien-15-oic acid (2), (-)-16α-hydroxycleroda-3,13 (14) Z-dien-15,16-olide (3), (+)-(4→2)-abeo-16(R/S)-2, 13 Z-kolavadien-15, 16-olide-3-al (4), (-)-3β, 16α-dihydroxycleroda-4(18), 13(14) Z-dien45,16-olide (5), (-)-3, 12 E-kolavadien-15-oic acid-16-al (6), (-)-labd-13 E-en-8-ol-15-oic acid (7), liriodenine (8), (-)-anonaine (9), (+)-isoboldine (10), (-)-asimilobine (11) and hordenine (12) have been isolated. This is the first report of 1, 6 and 10 from this plant species while 12 is reported for first time from this genus. Clerodane derivatives 1-7 were evaluated for their antimicrobial activity. Diterpene 3 was found to be most potent agent with MIC value of 6.25 μg/mL against Staphylococcus aureus and Sporothrix schenckii.

A spectroscopic study of the interaction of the fluorescent beta-carboline-3-carboxylic acid N-methylamide with DNA constituents: nucleobases, nucleosides and nucleotides

Interaction between beta-carboline-3-carboxylic acid N-methylamide, betaCMAM, and nucleobases, nucleosides and nucleotides is studied in the ground state with UV-visible, (1)H NMR and (31)P NMR spectroscopies and in the first excited state, with steady-state and time-resolved fluorescence spectroscopy. Job plots show a predominant 1:1 interaction in both electronic states. Association constants are estimated from changes in the absorption spectra, and show that the strongest interaction is produced with the nucleosides: 2'-deoxyadenosine (dAdo) and thymidine (Thd), and with the mononucleotides: 2'-deoxycytidine 5'- monophosphate (5'-dCMP) and uridine 5'- monophosphate (5'-UMP). These results are corroborated by the upfield shifts of two (1)H NMR resonances of the betaCMAM indole group. The (31)P NMR resonance of nucleotides is shifted downfield, suggesting the presence of electrostatic or hydrogen bond interaction with betaCMAM. In the first electronic singlet excited state, static and dynamic quenching of betaCMAM emission is achieved upon addition of nucleobases, nucleosides and nucleotides. This has been analysed using Stern-Volmer kinetics.