Identification and Characterization of the Caspase-Mediated Apoptotic Activity of Teucrium mascatense and an Isolated Compound in Human Cancer Cells.

Plants of the genus Teucrium (Lamiaceae or Labiatae family) are known historically for their medicinal value. Here, we identify and characterize the anticancer potential of T. mascatense and its active compound, IM60, in human cancer cells. The anti-proliferative effect of a T. mascatense methanol extract and its various fractions were analyzed in MCF-7 and HeLa cells in a dose- and time dependent manner. The dichloromethane fraction (TMDF) was observed to be the most effective with cytotoxicity against a more expanded series of cell lines, including MDA-MB-231. A time and dose-dependent toxicity profile was also observed for IM60; it could induce rapid cell death (within 3 h) in MCF-7 cells. Activation of caspases and PARP, hallmarks of apoptotic cell death pathways, following treatment with TMDF was demonstrated using western blot analysis. Inversion of the phosphatidylserine phospholipid from the inner to the outer membrane was confirmed by annexin V staining that was inhibited by the classical apoptosis inhibitor, Z-VAK-FMK. Changes in cell rounding, shrinkage, and detachment from other cells following treatment with TMDF and IM60 also supported these findings. Finally, the potential of TMDF and IM60 to induce enzymatic activity of caspases was also demonstrated in MCF-7 cells. This study, thus, not only characterizes the anticancer potential of T. mascatense, but also identifies a lead terpenoid, IM60, with the potential to activate anticancer cell death pathways in human cancer cells.

Enzyme inhibitory metabolites from endophytic Penicillium citrinum isolated from Boswellia sacra.

Fungal endophytes establish an important niche within the host plant through the secretion of chemical constituents. Isolation of bioactive metabolites could be a vital source for inhibiting the function of enzymes such as α-glucosidase and urease. The present study aimed to elucidate the potential of endophytes associated with Boswellia sacra through bioassay-guided isolation and identification of secondary metabolites with enzyme inhibitory ability. Endophytic fungal strains viz. Penicillium citrinum, P. spinulosum, Fusarium oxysporum, Alternaria alternata and Aspergillus caespitosus were identified through genomic DNA extraction, PCR amplification, sequencing and phylogenetic analysis. The enzymes inhibition analysis of the ethyl acetate extract from pure cultures suggested that P. citrinum possess significantly higher enzyme inhibitory activities compared to other strains. The active strain was subjected to chromatographic isolation and nuclear magnetic resonance methods to identify bioactive compounds. The bioactive extracts resulted in the isolation of 11-oxoursonic acid benzyl ester (1), n-nonane (2), 3-decene-1-ol (3), 2-Hydroxyphenyl acetic acid (4), and Glochidacuminosides A (5). Among pure compound, 11-oxoursonic acid benzyl ester (1) showed significantly higher enzyme inhibition activity compared to other metabolites. Our results suggest that the endophytic microorganism associated with the arid-land tree can offer a rich source of biologically active chemical constituents that could help discover lead drugs for enzyme inhibition.

Enzyme Inhibitory Radicinol Derivative from Endophytic fungus Bipolaris sorokiniana LK12, Associated with Rhazya stricta.

Endophytes, living inside plant tissues, play an essential role in plant growth and development, whilst producing unique bioactive secondary metabolites. In the current study, the endophytic fungus Bipolaris sorokiniana LK12 was isolated from the leaves of ethno-medicinal and alkaloidal rich Rhazya stricta. The bulk amount of ethyl acetate extract of fungus was subjected to advance column chromatographic techniques, which resulted in the isolation of a new radicinol derivative, bipolarisenol (1). It was found to be a derivative of radicinol. The structure elucidation was carried out by the combined use of 1D and 2D nuclear magnetic resonance, infrared spectroscopy, mass, and UV spectrometric analyses. The bipolarisenol was assessed for its potential role in enzyme inhibition of urease and acetyl cholinesterase (AChE). Results showed that bipolarisenol significantly inhibited the AChE activity with low IC50 (67.23 ± 5.12 µg·mL-1). Bipolarisenol inhibited urease in a dose-dependent manner with high IC50 (81.62 ± 4.61 µg·mL-1). The new compound also showed a moderate anti-lipid peroxidation potential (IC50 = 168.91 ± 4.23 µg·mL-1). In conclusion, endophytes isolated from medicinal plants possess a unique potential to be considered for future drug discovery.

New iridoid glycoside from Gratiola officinalis.

A new iridoid glycoside, 1ß,6ß-di-O-trans-cinnamoyl-9-O-ß-D-glucopyranosyl-3-iridene-5ß-ol (1), along with four known compounds loliolide (2), ß-sitosterol-3-O-ß-D-glucopyranoside (3), betulinic acid (4), and ß-amyrin (5), was isolated from the aerial parts of Gratiola officinalis L. The structure of the new compound was deduced on the basis of 1D ¹H and ¹³C NMR and 2D HMQC, HMBC, and COSY experiments, and mass spectrometric techniques (EI-MS and HR-EI-MS). The relative configuration of 1 was assigned by comparative analysis of the NMR spectral data with known analogs, together with NOESY experiments.

New robust sensitive fluorescence spectroscopy coupled with PLSR for estimation of quercetin in Ziziphus mucronata and Ziziphus sativa.

Flavonoids are natural antioxidants derived from plants and commonly found in a variety of foods to sequester free radicals. Quercetin, belonging to flavonol subclass of flavonoids, has received considerable attention because of its wide uses as a nutritional supplement as well as a phytochemical remedy for a number of diseases. In the current study, quantification of quercetin was carried out in two medicinally important flavonoid rich plant Ziziphus mucronata and Ziziphus sativa. Emission spectroscopy was utilized as a new method coupled with Partial Least Squares Regression (PLSR) and the cross validation was done by UV-Visible spectroscopy. The results indicated the higher quercetin content in Z. mucronata (1.50±0.034%) than Z. sativa (1.21±0.052%), and were further verified through Folin-Ciocalteu Colorimetric method (Z. mucronata; 1.41±0.26% and Z. sativa; 1.13±0.136%). In this study the sensitivity was explained in term of slope i.e. Slope=0.9973.

In vitro oxidative stress regulatory potential of Citrullus colocynthis and Tephrosia apollinea.

The present study investigates the potential role of medicinal plants Citrullus colocynthis and Tephrosia apollinea in ameliorating the oxidative stress developed during the generation of reactive oxygen species. Organic extracts of different organs (leaf, stem and root) of these medicinal plants obtained in n-hexane, chloroform, n-butanol and water were assayed for radical scavenging, total antioxidant capacity, anti-lipid peroxidation and reduced glutathione. The total phenolic content (TPC) of both selected medicinal plants was also evaluated. The results indicated that extracts of T. apollinea leaf, stem and root have higher TPC compared to those of C. colocynthis. Similarly, the results of the present study revealed higher bioactivity of C. colocynthis than that of T. apollinea in various antioxidant assays. Various plant parts of each plant were also compared.

In vivo evaluation of analgesic, anti-inflammatory, and neuropharmacological activities of the chemical constituent from Nepeta clarkei.

The plant species of genus Nepeta are used to treat various human diseases and for ornamental purposes as well. Nepethalate B (1) was isolated as a result of phytochemical investigations of Nepeta clarkei and was subjected in the present study for investigation of analgesic, anti-inflammatory, and central nervous system (CNS) depressant activities. The percentage inhibition in phase I of the acetic acid induced writhing test of compound 1 (dose of 0.1, 0.2 and 0.4 mg/kg of body weight) was 53.3, 58.0 and 86.7% respectively. These results were found significantly higher (P < 0.01) as compared to the negative control. Moreover, the percentage inhibitions of three phases for 0.1, 0.2 and 0.4 mg/kg were higher than the values obtained for Aspirin (positive control). In formalin test, the percentage pain inhibition between 0 and 5 min (early phase) was 68.0, 25.5, and 75.5% for 0.1, 0.2 and 0.4 mg/kg intra-peritoneal doses of compound 1 respectively. In case of late phase (20-30 min) it was 63.0, 66.7 and 48.1%, respectively. In comparison to aspirin, overall percentage inhibition of compound 1 was significantly higher in early and late phases. Interestingly, at all doses compound 1 showed more potent anti-inflammatory effects in terms of intensity and duration as compared to aspirin. The gross behavioral study of nepethalate B (1) was also carried out and the results revealed that it exhibited CNS depression in the mice and showed a prominent decrease in locomotor activity.

Analgesic, anti-inflammatory, and CNS depressant activities of new constituents of Nepeta clarkei.

Two new pentacyclic triterpenes named kirmanoic acid (1) and kurramanoic acid (2) have been isolated from the chloroform-soluble portion of the whole plant of Nepeta clarkei Hook. The structures of the two new compounds were assigned on the basis of their ¹H and ¹³C NMR spectra including two-dimensional NMR techniques such as COSY, HMQC, and HMBC experiments. Kirmanoic acid (1) was investigated for analgesic, anti-inflammatory, and CNS depressant activities. Interestingly kirmanoic acid (1) showed strong analgesic activity than standard drug in acetic induced writhing and formalin tests. Similarly kirmanoic acid (1) also showed strong anti-inflammatory activity than its standard drug. The gross behavioral study of kirmanoic acid (1) revealed that it exhibited mild CNS stimulant and muscle relaxant in the mice. Compound 1 showed a slight increase in Locomotor activity and possesses the antidepressant effect.