Metabolite profiling of Piper longum L. fruit volatiles by two-dimensional gas chromatography and time-of-flight mass spectrometry: Insights into the chemical complexity.

Piper longum L. (long pepper) is an economically and industrially important medicinal plant. However, the characterization of its volatiles has only been analyzed by gas chromatography-mass spectrometry (GC-MS). In the present study, precise characterization of P. longum fruit volatiles has been performed for the first time through advanced two-dimensional gas chromatography-time-of-flight spectrometry (GC×GC-TOFMS). A total of 146 constituents accounting for 93.79% were identified, of which 30 were reported for the first time. All these constituents were classified into alcohols (4.5%), alkanes (8.9%), alkenes (6.71%), esters (6.15%), ketones (0.58%), monoterpene hydrocarbons (1.64%), oxygenated monoterpenes (2.24%), sesquiterpene hydrocarbons (49.61%), oxygenated sesquiterpenes (13.03%), phenylpropanoid (0.23%), and diterpenes (0.2%). Among all the classes, sesquiterpene hydrocarbons were abundant, with germacrene-D (2.87% ± 0.01%) as the major one, followed by 8-heptadecene (2.69% ± 0.03%), ß-caryophyllene (2.43% ± 0.03%), n-heptadecane (2.4% ± 0.04%), n-pentadecane (2.11% ± 0.05%), and so forth. Further, 20 constituents were observed to be coeluted and separated precisely in the two-dimensional column. The investigation provides an extensive metabolite profiling of P. longum fruit volatiles, which could be helpful to improve its therapeutic potential.

Derivatives of Cinnamic Acid Esters and Terpenic Diversity in Volatiles of Thirty-Six Sand Ginger (Kaempferia galanga L.) Accessions of Eastern India Revealing Quality Chemovars.

The essential oil of Kaempferia galanga L. commonly known as sand ginger has increased its demand in national and international market for decades. Cinnamic acid esters like ethyl-p-methoxy cinnamate (EPMC) and ethyl cinnamate (EC) are major constituents in its essential oil. In spite of the high demand for the plant as raw material, identification of quality chemovars having high essential oil (EO) yield and constituents is still at an infant stage. With this in mind, we have evaluated the EO yield of 36 accessions from three provinces of Eastern India, which varied within a range of 0.41 ± 0.01 to 2.63 ± 0.03 v/w. Further, a total of 65 compounds were detected by gas chromatography and mass spectrometry (GC-MS) with area percentages varying from 76.16 to 97.3%. EPMC was found to be the major component in 14 accessions with area percentages varying from 10.7% to 41.1%, whereas other 22 accessions showed EC as the major constituent, varying from 16% to 29.1%. Further, a diversity study among accessions was performed by agglomerative hierarchical clustering (AHC) and principal component analysis (PCA) analysis based on the abundance of identified constituents, which categorized all 36 accessions into three clusters. Thus, the present study helps to identify quality chemovar K.g16 and K.g14 with respect to oil yield and constituents, respectively, which could be used to guide commercial cultivation and further improvement of the taxa.

Potential role of Indian long pepper (Piper longum L.) volatiles against free radicals and multidrug resistant isolates.

In the present study, the extracted volatiles from dried leaf and fruit of Piper longum were analysed by gas chromatography-mass spectrometry (GC-MS) and each detected 53 constituents having 92.41% and 96.31% of the total volatiles respectively. E-nerolidol (19.56%), ß-pinene (17.07%) and α-pinene (6.8%) were main constituents in leaf volatiles whereas the fruit volatiles dominated by germacrene-D (23.38%), 8-heptadecene (8.95%) and ß-caryophyllene (8.20%). Antioxidant potential of the volatiles were assessed by DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) assays. The fruit volatiles revealed higher radical scavenging activities as compared to leaf. The samples were also evaluated against multidrug resistant (MDR) isolates including one non MDR fungal strain. The fruit volatiles showed a very strong activity against Acinetobacter baumannii than others whereas leaf volatiles possessed strong activity against Klebsiella pneumoniae as compared to other strains. Thus, the dried fruits can be exploited for drug development towards therapeutic purpose.

Thermal desorption modulation based detection of volatile constituents of Alpinia galanga by two dimensional gas chromatography and time of flight mass spectrometry.

Alpinia galanga Wild.(L.) is well known for its aromatic constituents. Though the aromatic composition is already known, but lots of constituents which contributing overall aroma of the oil are still unknown due to the co-eluting factor of single column in GC-MS. Thus the current study aims to characterise maximum volatile constituents present in the essential oil of A. galanga using thermal desorption modulator of two-dimensional gas chromatography and time-of-flight mass spectrometry. The 102 compounds with good match and high probability value were identified out of which 42 were identified for the first time. The total identified compounds include 47 hydrocarbons 25 alcohols, 7 ketones, 7 esters, 3 aldehyde, 4 ethers and 9 other classified aromatic compounds. It was further categorised into Monoterpene Hydrocarbons, Oxygenated Monoterpenes, Sesquiterpene Hydrocarbons and Oxygenated Sesquiterpenes. The major constituent also varies with respect to area percentage. The in-depth characterisation will help in its qualitative analysis.

EST-SSR marker revealed effective over biochemical and morphological scepticism towards identification of specific turmeric (Curcuma longa L.) cultivars.

Turmeric (Curcuma longa L., family Zingiberaceae) is one of the most economically important plants for its use in food, medicine, and cosmetic industries. Cultivar identification is a major constraint in turmeric, owing to high degree of morphological similarity that in turn, affects its commercialization. The present study addresses this constraint, using EST-SSR marker based, molecular identification of 8 elite cultivars and 88 accessions in turmeric. Fifty EST-SSR primers were screened against eight cultivars of turmeric (Suroma, Roma, Lakadong, Megha, Alleppey Supreme, Kedaram, Pratibha, and Suvarna); out of which 11 primers showed polymorphic banding pattern. The polymorphic information content (PIC) of these primers ranged from 0.13 to 0.48. However, only three SSR loci (CSSR 14, CSSR 15, and CSSR 18) gave reproducible unique banding pattern clearly distinguishing the cultivars 'Lakadong' and 'Suvarna' from other cultivars tested. These three unique SSR markers also proved to be effective in identification of 'Lakadong' cultivars when analysed with 88 accessions of turmeric collected from different agro-climatic regions. Furthermore, two identified cultivars (Lakadong and Suvarna) could also be precisely differentiated when analysed and based on phylogenetic tree, with other 94 genotypes of turmeric. The novel SSR markers can be used for identification and authentication of two commercially important turmeric cultivars 'Lakadong' and 'Suvarna'.

Characterization of Kewda volatile components by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry.

Kewda (Pandanus fascicularis Lam.) is a well known medicinal and aromatic plant. The paper aims to precisely characterize volatile constituents present in Kewda flower oil using comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry (GCxGC-TOFMS). A total of 159 components were identified due to enhanced chromatographic separation and mass spectral deconvolution of GCxGC-TOFMS. On the basis of its chemical structure, the identified compounds were grouped into hydrocarbons, alcohols, ethers, ketones, esters, nitrogen compounds, aldehydes, acids, lactones, halides and sulfur containing compounds. Ethers were the major components. The predominant compounds identified by GCxGC-TOFMS were kewda ether, ortho-cymene and terpinen-4-ol. A database containing retention indices of compounds was created for the bi-dimensional column, thus proving to be a remarkable step for analysis of constituents using a GCxGC system. GCxGC-TOFMS separated a number of co-eluting components which were unresolved on a single GC column.