Influence of different preparation techniques on the composition and antioxidant action of curcumin and curcuminoids

Epidemiological evidence indicates that plant antioxidants activity can treat or help to prevent the development of various diseases. One species with great potential as an antioxidant is Curcuma longa. However, different extraction techniques can influence isolated chemical compounds. This study investigated chemical composition and antioxidant activity of two rhizome extracts of C. longa: hydroethanolic, obtained by exhaustion (HECLex); and dried by a spray dryer (HECLsd). The phytochemical composition was evaluated by GC/MS. Antioxidant activity was evaluated using DPPH and FRAP assays. Total phenolic compounds and soil analyses were performed. The main components of HECLex were ar-turmerone, γ-curcumene, α-turmerone, and β-sesquiphellandrene. The main components of HECLsd were 9,12,15-octadecatrienoic acid, 2,3-bis([trimethylsilyl]oxy)propyl ester, verrucarol, and 1-monolinoleoylglycerol trimethylsilyl ether. HECLsd had significantly higher levels of phenolic compounds and higher antioxidant capacity compared with HECLex. In conclusion, processes of the preparation of C. longa rhizomes alter the chemical components and consequently their biological activity.

Pinus roxburghii constituents augment human lymphocytes mediated cytotoxicity towards cancer cells.

Background: Pinus roxburghii has been used in the Himalayan region as folkloric remedy while nothing is yet known about its immunomodulatory potential. Methods: The crude extracts of green and fallen pine needles were subjected to sequential fractionation to get partially purified fractions. Human peripheral blood lymphocytes (PBL) were used to analyze immunoenhancing potential of these fractions. Microcytotoxicity assay was employed to investigate improved cancer cells killing capabilities of PBL against various cancer cell lines. GC-MS was carried out to identify the major compounds in the bioactive fractions. Results: The lymphocyte proliferation assay depicted the immunoenhancing potential of extracts and fractions of fallen and green needles of P. roxburghii. The ethyl acetate fractions of both fallen and green needles displayed highest mitogenic activity on human PBL. Both fractions heightened the expression of cell surface markers (CD3, CD8, and CD56) and significantly increased the production of cytokines (IL-2, IFN-γ and TNF-α). The enhanced intracellular granulysin (immunomarker for activated CTLs and NK cells) expression also confirmed immune stimulatory potential of these fractions on human lymphocytes. The ethyl acetate fractions of pine needles enhanced the cytotoxicity of PBL towards various cancer cells (HCT-116, HeLa, PC-3 and A549) as compared to untreated PBL. GC-MS analysis showed presence of major compounds like 3-α-mannobiose, octakis (trimethylsilyl) ether, methyloxime in ethyl acetate fraction of the green needles and cyclodecasiloxane, eicosamethyl in ethyl acetate fraction of the fallen needles. Conclusion: The bioactive fractions of the fallen and green needles of P. roxburghii stimulate cancer cells killing potential of human lymphocytes.

The antifungal activity of vapour phase of odourless thymol derivate

Thymol is a substance with a great therapeutic potential possessing antibacterial and antifungal activity, with a characteristic odour that remains long after application but is not pleasant at higher concentrations. In this study, attention has been focused on describing the chemical and biological properties of the simply prepared trimethylsilyl ether of thymol (kubicin). Interestingly, kubicin has similar volatility as thymol, undergoes hydrolysis in the water (moisture; forming thymol and trimethylsilanol) and can be used at 6,000 times higher concentration than thymol without any negative and irritating odour. Kubicin showed diverse fungistatic and fungicidal activities when tested by direct contact assay, or in vapour phase. The volatile vapour of kubicin was effective on all tested fungal strains. These results suggest that vapours of kubicin might provide an alternative way to fight against fungal contamination.

Phytochemical and GC-MS Analysis of Dendrophthoe falcata (L.f.) Ettingsh Stem

Dendrophthoe falcata (L.f.) Ettingsh is an important medicinal plant belonging to the family Loranthaceae. It is perennial, climbing and woody parasitic plant of family Loranthaceae. It is ethnomedicinally used for treating ulcers, asthma, impotence, paralysis skin diseases and wounds. In the present study, an attempt was made to investigate the phytochemical constituents present in the Dendrophthoe falcata (L.f.) Ettingsh stem. The preliminary phytochemical screening in different solvents extract was done by using standard methods. The phytochemical screening revealed the presence of carbohydrates, protein and amino acids, fixed oils and fats, saponins, sterols, alkaloids, phenols, tannins, flavonoids, anthocyanin and anthraquinones in different solvent extracts. GC-MS analysis was performed on the methanolic extract to find out the chemical constituents. The GC-MS study revealed the presence of about 51 bioactive compounds. Cyclopentasiloxane, Cyclohexasiloxane, Cycloheptasiloxane, Cyclooctasiloxane, Cyclononasiloxane, Phthalic acid, Hexadecanoic acid, Cyclodecasiloxane, Cyclononasiloxane, Tetracosane, Tetratriacontane, Benzoic acid, 1-Monolinoleoylglycerol trimethylsilyl ether, Octadecane, ç-Sitosterol are some of the major phytoconstituents reported from the sample. Further research work is needed on these identified compounds to analyse their mode of action and usefulness in phytopharmaceutical industries.

Leaf Cuticle Can Contribute to Non-Host Resistance to Poplar Leaf Rust

The plant leaf cuticle is a chemically complex but largely waxy outer shell that limits water loss and also prevents some pathogens from gaining access to internal mesophyll. Rust fungi are obligate parasites, and most bypass the cuticle by thigmotropically locating stomata, growing through the stomatal openings, and then parasitizing mesophyll cells with haustoria. It is thought that even non-hosts of a given rust fungus do not resist until their mesophyll cells are contacted in this way. In other words, it is thought that the cuticle plays no role in non-host resistance. Here, we tested the hypothesis that poplar leaf cuticles might contribute to non-host resistance to rust fungi by chemically impeding the germination and growth of urediniosporelings of Melampsora larici-populina. Following an initial survey in China of the resistance of 36 genotypes of various species and interspecific hybrids of Populus to M. larici-populina, we selected three genotypes for the initial test of hypothesis: (1) A Populus purdomii genotype that is fully susceptible; (2) a Populus deltoides cv. ‘I-69′ that is incompletely resistant (i.e., a resistant host); and (3) a Populus tomentosa genotype that is a non-host to M. larici-populina. Urediniospores were assayed for germination in extracts of the cuticles of the three genotypes. Germination was most reduced by the P. tomentosa non-host cuticular extracts that also reduced the growth of germ tubes to 36 times less than that in controls or in the extract of the susceptible P. purdomii. Four cuticular components were identified as putative defense compounds given greater concentrations in P. tomentosa than in P. purdomii: Aucubin, hexakis(trimethylsilyl) ether, catechol, 7,9-Di-tert-buty l-1-oxaspiro (4,5) deca-6, 9-diene-2,8-dione and trifluoroacetamide. These four compounds were then tested, and they reduced urediniospore germination and uredinial density in inoculations of normally susceptible P. purdomii with Melampsora larici-populina. Thus, the cuticle of P. tomentosa can contribute to pre-haustorial, non-host resistance to M. larici-populina.

Identification of the chemical constituents of aqueous and alcoholic Glycyrrhiza glabra root extracts and its comparative apoptotic study against human hepatocarcinoma cell line

Introdution: Hepatocellular carcinoma (HCC) is one of the most common cancers. It is the third leading cause of cancer related death. This study aimed to evaluate the phytochemical composition of ethanolic and aqueous Glycyrrhiza glabra root extracts its apoptotic effects against human hepatocarcinoma HepG2 cell line. Methods: In the current experimental study, the phyochemical composition of aqueous and ethanolic Glycyrrhiza glabra extract was evaluated by GC/MS method. The HepG2 cells were grown in RPMI1640 supplemented with 10 % (v/v) FBS at 37°C with 5 %carbon dioxide (CO2) atmosphere. The cytotoxicity activities of extracts were measured using MTT after 24 hours. To evaluate the ability of extracts to trigger apoptosis in HepG2 cells, the Hosest8778 staining method was carried out. Results: The phytochemical data of aqueous extract revealed 18 compounds, including Dodecane (13.34%) and 2',6'-Dihydroxyacetophenone bis (trimethylsilyl) ether (12.48%) as the major constitutes. The chemical composition of ethanolic extract showed 17 compounds, including Pentadecane (7.78%), 2,6,11,15-Tetramethylhexadecane (4.67%) as the prominent compounds. The MTT results revealed that the extract-treated cells had a dose-related toxicity effects. The results of Hoechst 33258 staining showed that the nuclear DNA fragmentation was increased in the ethanolic extract treatment compared to aqueous extract. Conclusion: The ethanolic extract of Glycyrrhiza glabra possesses more apoptotic effect on cancer cells and further researches are needed for investigating its potential mechanism.