Analysis of Volatile Molecules Present in the Secretome of the Fungal Pathogen Candida Glabrata

Candida albicans, Candida glabrata, Candida parapsilosis and Candida tropicalis are the four most common human fungal pathogens isolated that can cause superficial and invasive infections. It has been shown that specific metabolites present in the secretomes of these fungal pathogens are important for their virulence. C. glabrata is the second most common isolate world-wide and has an innate resistance to azoles, xenobiotics and oxidative stress that allows this fungal pathogen to evade the immune response and persist within the host. Here, we analyzed and compared the C. glabrata secretome with those of C. albicans, C. parapsilosis, C. tropicalis and the non-pathogenic yeast Saccharomyces cerevisiae. In C. glabrata, we identified a different number of metabolites depending on the growth media: 12 in synthetic complete media (SC), 27 in SC-glutamic acid and 23 in rich media (YPD). C. glabrata specific metabolites are 1-dodecene (0.09 ± 0.11%), 2,5-dimethylundecane (1.01 ± 0.19%), 3,7-dimethyldecane (0.14 ± 0.15%), and octadecane (0.4 ± 0.53%). The metabolites that are shared with C. albicans, C. glabrata, C. parapsilosis, C. tropicalis and S. cerevisiae are phenylethanol, which is synthesized from phenylalanine, and eicosane and nonanoic acid (identified as trimethylsilyl ester), which are synthesized from fatty acid metabolism. Phenylethanol is the most abundant metabolite in all fungi tested: 26.36 ± 17.42% (C. glabrata), 46.77 ± 15.58% (C. albicans), 49.76 ± 18.43% (C. tropicalis), 5.72 ± 0.66% (C. parapsilosis.) and 44.58 ± 27.91% (S. cerevisiae). The analysis of C. glabrata’s secretome will allow us to further our understanding of the possible role these metabolites could play in its virulence.

Sandalwood, an Indian medicinal plant attenuates the microbial growth and influence up/down regulation of the metabolites

The methanolic extract of sandalwood (SwME) was prepared by soxhlet apparatus and the antibacterial assay was performed. Further, the metabolite profiling of SwME and lysates of E. coli and E. coli grown in the presence of SwME was generated. SwME showed maximum inhibition against E. coli (MTCC 443) i.e. 82.71%, and minimal against B. subtilis (MTCC 736) i.e. 26.82%. The metabolome profiles of E. coli and SwME were generated using gas chromatography-mass spectrometry (GC-MS) technique. Comparative studies were done to understand to what extent metabolite modifications differ between SwME, E. coli lysate and the E. coli strain grown in presence of extract. Result revealed 23 peaks with major compounds present in E. coli were 9-Octadecenoic Acid (Z)-, Methyl Ester (26.85%), Hexadecanoic Acid, methyl ester (20.5%) and Hexadecanoic acid, trimethylsilyl ester (15.79%). When E. coli was grown in the presence of SwME, GC-MS analysis showed 25 peaks with major compounds such as 9-Octadecenoic Acid, Methyl Ester (21.97%), Hexadecanoic Acid, Methyl Ester (17.03%), and Hexadecanoic Acid, Trimethylsilyl Ester (14.96%). Correlating the metabolic profiles with the changes occurring is essential to progression their comprehension and in the development of new approaches to identify the metabolomics regulation in E. coli in response to SwME.

A novel lung alveolar cell model for exploring volatile biomarkers of particle-induced lung injury

Quartz can increase oxidative stress, lipid peroxidation, and inflammation. The objective of this study was to explore the volatile biomarkers of quartz-induced lung injury using a lung alveolar cell model. We exposed the human alveolar A549 cell line to 0, 200, and 500 μg/mL quartz particles for 24 h and used gas chromatography–mass spectrometry to measure the volatile metabolites in the headspace air of cells. We identified ten volatile metabolites that had concentration–response relationships with particles exposure, including 1,2,4-oxadiazole, 5-(4-nitrophenyl)-3-phenyl- (CAS: 28825-12-9), 2,6-dimethyl-6-trifluoroacetoxyoctane (CAS: 61986-67-2), 3-buten-1-amine, N,N-dimethyl- (CAS: 55831-89-5), 2-propanol, 2-methyl- (CAS: 75-65-0), glycolaldehyde dimethyl acetal (CAS: 30934-97-5), propanoic acid, 2-oxo-, ethyl ester (CAS: 617-35-6), octane (CAS: 111-65-9), octane, 3,3-dimethyl- (CAS: 4110-44-5), heptane, 2,3-dimethyl- (CAS: 3074-71-3) and ethanedioic acid, bis(trimethylsilyl) ester (CAS: 18294-04-7). The volatile biomarkers are generated through the pathways of propanoate and nitrogen metabolism. The volatile biomarkers of the alkanes and methylated alkanes are related to oxidative and lipid peroxidation of the cell membrane. The lung alveolar cell model has the potential to explore the volatile biomarkers of particulate-induced lung injury.

FTIR, GC-MS and HPLC analysis of Baliospermum montanum (Willd.) Muell. Arg.

The present work is aimed to determine the chemical constituents in Baliospermum montanum methanolic extracts. An in vitro regenerated procedure was developed for the induction of callus from stem explant cultured on Murashige and Skoog (MS) medium fortified with various concentration and permutations of 2, 4-dichloro phenoxy acetic acid, 1-naphthalene acetic acid, 6-benzyl amino purine and gibberellic acid. FTIR & GC-MS analysis was done according to standard procedure. The quantitative estimation of β-sitosterol was done by HPLC method. Maximum fresh and dry weight of callus was estimated in the combination of GA3 (0.5 mg/L) + NAA (2 mg/L) compared to other concentration. The FTIR analysis showed various functional compounds with different characteristic peak values in the extracts. Major bioactive constituents were recognized in the GC-MS analysis. Root extract revealed the existence of 1-hexadecanol, pentanoic acid, 2-(aminooxy)- and 1-hexacosanol. Leaf extract showed the presence of propanoic acid, 2-oxo-, trimethylsilyl ester, 9,12-octadecadienoic acid (z,z)-, trimethylsilyl ester, docosane, 1,22-dibromo- and pentatriacontane. Stem and stem derived callus exhibit the presence of 1,6,3,4-dihydro-2-deoxy-beta-d-lyxo-hexopyranose, n-hexadecanoic acid and pentanoic acid, 2-(aminooxy). The methanolic extract of leaf exhibited 0.2149 % of β-sitosterol content. There were no peaks observed in the root, stem and stem derived callus. Further studies are necessary for the isolation and characterization of bioactive compounds from B. montanum.

One Pot Conversion of Carboxylic Acid to Ketone Using Trimethylsilyl Chloride

Background: Ketone is abundant in many natural products and in pharmaceuticals. It is believed to be one of the important functional groups in organic chemistry. Till date,several research approaches have been made to access ketone from a readily available starting materials. One such notable transformation consists of the conversion of carboxylic acid to the corresponding ketone in a one pot manner. Objective: We aimed to develop a simple one pot reaction for the conversion of carboxylic acid to ketone. This reaction could be useful to convert all types of carboxylic acid to ketone in a facile manner. Methods: In this procedure, a carboxylic acid has been converted to the corresponding trimethylsilyl ester using trimethylsilyl chloride in the presence of a base. A suitable organometallic reagent can interact with the ester formed at 20°C to produce the corresponding ketone. Results: Under the optimized reaction conditions, various aromatic, aliphatic and heteroaromatic carboxylic acids have been converted to the corresponding ketones using organolithium reagents, in a one pot manner. Moderate to good yields of the desired ketones were observed in most of the transformations. Conclusion: Conversion of carboxylic acid to ketone has been reported in a one pot fashion, where carboxylic acid has been transformed to its silyl ester. Organolithium reagents were used as nucleophile for our reaction purpose, whereas the organomagnesium reagents were not useful for this transformation. Aliphatic, aromatic and heteroaromatic carboxylic acids have been converted to the ketones following a simple process.

UPLC-ESI-MS/MS and Various Chromatographic Technique for Identification of Phytochemicals in Populus euphratica Oliv. Leaves Extract

The aim of this study is to screen the phytochemicals found in Populus euphratica leaves since this type of trees are used traditionally by many villagers as treatment for eczema and other skin disease and also this plant is poorly investigated for their phytochemicals especially in Iraq. Phytochemical screening of the extracts obtained from the n-hexane and chloroform fraction of leaves of Populus euphratica was done by Thin-layer chromatography and various spraying reagents to test if alkaloids, sterols and other compounds are present. UPLC-electrospray ionization –tandem mass spectroscopy along with GC-MS and HPTLC are used to identify the phytochemicals present in the plant leaves.UPLC-ESI-MS/MS method 20 compounds have been identified in various fractions among which are protopine alkaloids. salicin, salicortin, tremulacin. GC-MS showed that the observed data obtained are matched with that in NIST library and confirmed the presence of Hexadecanoic acid trimethylsilyl ester in 43.80% beta-Sitosterol in 37.14% and Diisooctyl phthalate 11.46%.UPLC-ESI-MS/MS is a powerful method for the identification of compounds in mixture based on comparison of their molecular, weight retention time and MS/MS fragmentation. Protopine alkaloid is identified for the first time in Populus euphratica and genus Populus. GC-MS is a valuable method for both qualification and quantification of various phytochemicals that are volatile in nature Keywords: Populus euphratica, GC-MS, phytochemical, UPLC-ESI-MS/MS

Fourier transform infrared and gas cromatography-mass extracts from Euscaphis japonica bark

Due to the lack of studies on the chemical constituents of Euscaphis japonica bark, infrared spectroscopy and gas chromatography-mass spectrometer (GC-MS) techniques were used to analyze the ethanol, phenyl alcohol and methanol extracts from Euscaphis japonica bark, laying a foundation for the efficient utilization of Euscaphis japonica bark. Through experimental verification, different extracts of Euscaphis japonica bark can yield different chemical substances: Stigmast-4-en- 3-one, (1R,8a alpha)-1,4a beta-dimethyl -7 beta -(1-hydroxy-1-methylethyl)decalin-1 alpha-ol, lactose, Vitamin E, 9,12-octadecadienoic acid, n-hexadecanoic acid, Arsenous acid Tris(trimethylsilyl)ester 4-hydroxy-3-methoxycianamylic alcohol, etc. It was determined that most of the chemicals in Euscaphis japonica bark are soluble in ethanol reagents. According to the relevant mass spectrometry data, Euscaphis japonica bark contains useful pharmaceutical ingredients and chemical raw materials and has broad development prospects.