Gas Chromatography-mass Spectrometry Profiling Research Articles

Solvent extraction and its effect on phytochemical yield and antioxidant capacity of woody medicinal plant, Polyalthia bullata

Polyalthia bullata is a woody medicinal plant that contains antioxidant compounds. Finding a suitable solvent is important to obtain a high yield of antioxidants in the phenolic, flavonoid, and terpenoid families. In this study, from different solvent extracts, the leaf methanolic extract exhibited the highest total phenolic content (TPC), total flavonoid content (TFC), total terpenoid content (TTC), and total antioxidant activity. For woody parts of stem and roots, methanol was the best solvent for all phytochemicals except for phenolics, which accumulated in the roots and were extracted more efficiently using ethanol. However, the methanolic extracts from both tissues displayed the best antioxidant capacity. Gas chromatography-mass spectrometry (GC-MS) profiling data showed the presence of antioxidant compounds such as thymol, phytol, and neophytadiene in the leaf; trans-farnesol, n-hexadecanoic acid, and 9-Octadecenamide in the stem; and fatty acid (cis-vaccenic) and its methyl ester (11-Octadecanoic acid, methyl ester and [1,1’-bicyclopropyl]-2-octanoic acid, 2’-hexyl-methyl ester) in the roots. These findings reveal important compounds that are present in different plant parts of P. bullata.

Lantana trifolia: Phytochemical and elemental composition, proximate contents and gas chromatography–mass spectrometry profile

Background: With increasing concern over food insecurity, there is the need to incorporate wild edible plants in our meals as they can provide adequate level of nutrition when consumed as food. Aim: The objective of this study was to evaluate the proximate composition, elemental composition, total phenolic content, total flavonoid content and gas chromatography–mass spectrometry (GC-MS) profile of Lantana trifolia . Setting: This study was carried out in Juja, Kenya where the samples were collected, prepared and stored at the Department of Chemistry, Jomo Kenyatta University of Agriculture and Technology. Methods: The proximate and elemental compositions of the leaves, stalk and root samples were evaluated by using standard procedures, whilst the total phenolic and flavonoid contents were evaluated by using Folin–Ciocalteu and aluminium chloride method. The secondary metabolites present in the crude methanolic extracts of the whole plant were determined by using GC-MS. Results: The proximate and elemental analyses of the plant revealed that L. trifolia can be a good source of essential elements, proteins, crude fibre and carbohydrates. The protein, fat, crude fibre and carbohydrate contents in the leaves were found to be higher compared with the stalks and roots, whilst the ash and moisture contents were found to be higher in the roots. The concentrations of calcium, iron, magnesium and zinc in the leaves were found to be 8860.75 ± 565.27, 11 003.10 ± 143.24, 1520.25 ± 26.85 and 39.66 ± 15.68 mg/kg, respectively, compared with the roots and stalks, which were lower. Conclusion: The concentration of total phenolic and total flavonoid compounds and GC-MS profile of the methanolic extracts revealed that L. trifolia can be a good source of secondary metabolites, some of which have reported to be free radical scavengers. Hence, L. trifolia can not only be used as a source of important secondary metabolites, but its nutritional content suggests that the plant can be used to combat nutrient deficiency amongst many communities who lack adequate resources, because it thrives in the wild.

Volatiles from soil‐borne fungi affect directional growth of roots

Volatiles play major roles in mediating ecological interactions between soil (micro)organisms and plants. It is well‐established that microbial volatiles can increase root biomass and lateral root formation. To date, however, it is unknown whether microbial volatiles can affect directional root growth. Here, we present a novel method to study belowground volatile‐mediated interactions. As proof‐of‐concept, we designed a root Y‐tube olfactometer, and tested the effects of volatiles from four different soil‐borne fungi on directional growth of Brassica rapa roots in soil. Subsequently, we compared the fungal volatile organic compounds (VOCs) previously profiled with Gas Chromatography–Mass Spectrometry (GC–MS). Using our newly designed setup, we show that directional root growth in soil is differentially affected by fungal volatiles. Roots grew more frequently toward volatiles from the root pathogen Rhizoctonia solani, whereas volatiles from the other three saprophytic fungi did not impact directional root growth. GC–MS profiling showed that six VOCs were exclusively emitted by R. solani. These findings verify that this novel method is suitable to unravel the intriguing chemical cross‐talk between roots and soil‐borne fungi and its impact on root growth.

Antioxidant activity and GC-MS profile of Conyza bonariensis L. leaves extract and fractions

The 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing power (FRAP), and semivolatile compounds of Conyza bonariensis L. leave extract and fractions are discussed. A methanolic crude extract was obtained through maceration, and subsequently, n-hexane, chloroform, and ethyl acetate fractions were collected using a solvent-solvent partition. Total phenols, flavonoids, and antioxidant activity assays were performed in an ultraviolet-visible (UV-Vis) spectrophotometer, and the results were expressed as Gallic Acid, Quercetin, and Trolox equivalents respectively. The findings achieved indicate that ethyl acetate fraction showed the highest DPPH radical scavenging capacity (90.69±3.16%) at 500 µg mL-1, and reduced the ferric tripyridyltriazine complex (Fe3+-TPTZ) with values between 19.68 and 2,355.37 mg Trolox equivalent (TE) g-1. It was identified 28 phytoconstituents through Gas chromatography-mass spectrometry (GC-MS). The scavenging activity of ethyl acetate fraction could be correlated mostly to the presence of eugenol, trans-isoeugenol, lucenin-2, methyl salicylate, and syringic acid. This study reveals that the ethyl acetate fraction could be used as a good source of antioxidants for health benefits.

Microbially induced calcite precipitation using Bacillus velezensis with guar gum.

Mineral precipitation via microbial activity is a well-known process with applications in various fields. This relevance of microbially induced calcite precipitation (MICP) has pushed researchers to explore various naturally occurring MICP capable bacterial strains. The present study was performed to explore the efficiency of microbially induced calcite precipitation (MICP) via locally isolated bacterial strains and role of guar gum, which is a naturally occurring polymer, on the MICP process. The strains were isolated from local soil and screened for urease activity Further, the urease positive strain was subjected to urea and calcium chloride based medium to investigate the efficacy of isolated strain for microbial induced precipitation. Among screened isolates, the soil bacterium that showed urease positive behaviour and precipitated calcium carbonate was subjected to 16S rRNA gene sequencing. This strain was identified as Bacillus velezensis. Guar gum-a natural polymer, was used as a sole carbon source to enhance the MICP process. It was observed that the isolated strain was able to breakdown the guar gum into simple sugars resulting in two-fold increase in calcium carbonate precipitate. Major bio-chemical activities of isolated strain pertaining to MICP such as ammonium ion concentration, pH profiling, and total reducing sugar with time were explored under four different concentrations of guar gum (0.25%, 0.5%, 0.75% and 1% w/v). Maximum ammonium ion concentration (17.5 μg/ml) and increased pH was observed with 1% guar gum supplementation, which confirms augmented MICP activity of the bacterial strain. Microstructural analysis of microbial precipitation was performed using scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques, which confirmed the presence of calcium carbonate in different phases. Further, XRD and SEM based studies corroborated that guar gum supplemented media showed significant increase in stable calcite phase as compared to media without guar gum supplementation. Significant diverse group of nitrogenous compounds were observed in guar gum supplemented medium when subjected to Gas Chromatography-Mass spectrometry (GC-MS) profiling.

Evaluation of bioactive compounds, free radical scavenging and anticancer activities of bulb extracts of Boophone disticha from Eastern Cape Province, South Africa.

Boophone disticha (B. disticha) is a bulbous tropical and subtropical flowering plant widespread in Africa, which is frequently used to treat several human ailments. Until the present, there is no scientific validation on the biological activity of this plant from the Eastern Cape Province of South Africa and as a result, this study aimed to assess the bioactive compounds, free radicals scavenging and anticancer potentials of crude bulb extracts (chloroform, acetone, and ethanol) of Boophone disticha obtained from this geographical location. Standard biochemical techniques and Gas-chromatography mass spectrometry (GCMS) analysis were used to pinpoint the bioactive compounds in the crude extracts sequel to their antioxidant potentials against radicals such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), hydrogen peroxide and nitric oxide as well as their ferric ion reducing power. In addition, their cytotoxicity effects against Human cervix adenocarcinoma (HeLa) cells were assessed as an in vitro model for anticancer. The phytochemical evaluation of the crude extracts showed the presence of phenolics, flavonoids, and alkaloids. GCMS profiles confirmed the presence of some bioactive compounds in the crude extracts of B. disticha that could be responsible for their biological activities. The plant extracts possessed considerable antioxidant activity and exhibited dose-dependent radicals’ inhibition from all assays carried out. Furthermore, the cytotoxicity effects against HeLa cells recorded inhibition concentration (IC50) of 1.5, 1.6, and 1.9 µg/mL for acetone, chloroform, and ethanolic extracts of B. disticha, respectively. Findings from the present study suggest that B. disticha could be a good prospective source of antioxidant and anticancer agents. Therefore, further research on the isolation and purification of compounds from these extracts are indispensable.

GC-MS Profiling of Anti-bacterial Metabolic Compounds from the Extract of Azadirachta indica

Azadirachta indica is a very common plant used very frequently due to its medicinal significance. The antibacterial activities of 0.001, 0.01, 0.1, 1.0 and 10 mg/mL of the plant extract were determined against different pathogenic bacteria. Concentration of 0.01 mg/mL killed the E. coli, E. aerogenes, P. stuartii and 10, 1.0 and 0.1 mg/mL were very effective against the E. cloacae, K. pneumoniae and P. mirabilis and killed them 100% in culture plates. The plant extracts were analyzed for the characterization of the different antimicrobial compounds through gas chromatography-mass spectrometry (GC-MS). An array of antibacterial compounds such as azulene, tetrasiloxane, phthalic acid, cyclopentasiloxane, hexadecanoic acid, spiropentane, dioctyl phthalate were detected in the plant extract through GC-MS. The antibacterial activities of the plant extracts were might be because of their compound which had been reported previously as well as antimicrobial compounds.

Gas Chromatography-Mass Spectrometry Profiling of Pimpinella anisum Oils and its Antimicrobial and Antioxidant Activities

Essential and fixed oils of anise plant Pimpinella anisum growing in Iraq have been investigated regarding their chemical components, antioxidant, and antimicrobial properties. Essential oils were extracted using the Clevenger-apparatus, while fixed oil was extracted using a Soxhlet apparatus. Gas chromatography-mass spectrometry (GC-MS) was used for the analysis of the oil components. Six strains of bacteria, namely S. epidermidis, S. aureus, E. coli, B. cereus, P. vulgaris, and S. typhimurium were tested against the antimicrobial activity of each oil. Anise oil demonstrated a broad antibacterial property range, against gram-positive and gram-negative bacteria, through the inhibition zone. The antibiotic sensitivity test was performed by disk diffusion process against the test organisms. The agar dilution method was used at five different concentrations (12.5, 25, 50, 100, and 200 mg/mL) throughout the test. The minimum inhibitory concentration (MIC) was determined for each volatile and fixed oil. The DPPH radical scavenging assay was used to test the antioxidant activities of essential and fixed oils. Anise oil showed excellent antioxidant activity, in comparison with the reference compounds. Anise oil has the potential to be used as a therapeutic, antimicrobial, and antioxidant agent.

Chemical Fingerprinting of Nauclea latifolia, an Antidiabetic Plant, Using GC-MS

Aim: Earlier studies have established the antidiabetic activity of Nauclea latifolia. The aim of this study was to obtain chemical fingerprints of the ethanolic extracts of Nauclea latifolia leaf using Gas chromatography-Mass spectrometry (GC-MS), in order to assure proper identification of the plant and to evaluate its phytochemical composition using GC-MS. It was also aimed at unravelling the phytochemical constituents responsible for its antidiabetic activities.
 Methodology: The phytochemicals in the plant leaves were extracted by cold maceration in ethanol and subjected to GC-MS analysis.
 Results: Chromatograms showed 51 peaks of identified phytochemical compounds. The GC-MS analysis also revealed sixteen (16) active antidiabetic phytochemicals namely: Pentanoic acid 4-oxo- ethyl ester, 2-Methoxy-4-vinylphenol, Triethyl citrate, Quinic acid, 3-O-Methyl-d-glucose, 3,7,11,15-tetramethyl-2-hexadecen-1-ol, Phytol, Hexadecanoic acid, 9,12-octadecadienoic acid, 9,12,15-octadecatrienoic acid, Octadecanoic acid, Hexadecanoic acid 2-hydroxy-1-(hydroxymethyl) ethyl ester, Vitamin E, Campesterol, Stigmasterol, Gamma-sitosterol.
 Conclusion: The GC-MS profile provides a suitable chemical fingerprint to assure proper identification of the Nauclea latifolia plant. Sixteen (16) active phytochemicals of the plant leaf are known to have antidiabetic activities; these could be used as a basis for standardization of the plant preparations for diabetes therapy.

Gas Chromatography-Mass Spectrometry (GC-MS) Profiling of Hops and Some Nigerian Potential Hop Substitutes: Comparative Studies in Beer Brewing

Isomerized hop extract and methanolic extracts of Azadirachta indica, Garcinia kola, Gongronema latifolium and Vernonia amygdalina were profiled by the application of Gas Chromatography-Mass Spectrometry (GC-MS). The isomerized hop extract and ethanolic extracts of the plant species were used to brew beers. The aim was to study the GC-MS profiles of all the extracts comparatively and to investigate some physicochemical properties of beers brewed with hop extracts and in comparison, with beers brewed with extracts from the four Nigerian plants. The profiling of the metabolites in hop extracts and those of the Nigerian plants was carried out using Gas Chromatography - Mass Spectrometer. The physicochemical properties of the finished beer products were also carried out using standard methods. Beers brewed with extracts from the Nigerian plants were statistically ranked by the application of Analysis of Variance (ANOVA) to ascertain their potentiality. The GCMS results showed that these plants contained metabolites comparable to those of hops, although some metabolites [dehydro-cohumulunic acid; 4,4-dimethyl- 2-buten-4-olide; 1,2-dimethyl-cyclopropane carboxylic acid; lupulone; 2,5-dimethyl-2-hexanol; 4,4,5,5-tetramethylbicyclo hexyl-6-ene-2,3-dione; octadecanoic acid, oxiranyl methyl ester and 1,2-benzenedicarboxylic, bis(-2-ethyl hexyl) ester] present in hops were absent in the Nigerian plants. Isomerized hop, hop leaf, G. kola and V. amygdalina extracts contained 14, 11, 12 and 9 metabolites respectively while those of A. indca and G. latifolium contained 10 metabolites each. The physicochemical properties of the brewed beers revealed that the alcohol content in all the beer samples ranged from 3.43-3.75%, total acidity (0.132-0.324%), pH (5.47-5.68), turbidity (5-125NTU), total solids (3.66- 8.16%) and bitterness level (25.38-39.62IBU). The concentration of arsenic in the beer samples ranged from 1.44- 1.77ppm, cadmium (0.00-0.97ppm) and copper (0.10-2.70ppm). Test of significant (p-value) in all the tested plants was greater than 0.05 at 95% confidence interval. Consequently, the extracts from tested Nigerian plants could be used as suitable substitutes for hops in beer brewing without alteration of physicochemical properties of beer, G. kola having the greatest potential as substitute for hops.

Gas Chromatography-Mass Spectrometry Profile of Essential Oils Derived from Zingiber officinale Rosc. Rhizome

White ginger which is also called Jahe Putih (Zingiber officinale) in Indonesia, is widely used in local Indonesian communities. It is a popular ingredient in beverages for stamina and also a bioactive ingredient for many traditional Indonesian food recipes. It is a popular ingredient in beverages for stamina and also a bioactive ingredient for many traditional food recipes. However, with the increase in demand for ginger related products, fake ginger formulated products are widespread in the market. This paper is disclosed the chemical profile of essential oil obtained from steam distillation of the local ginger. The results of this study can be used as a standard to detect original ginger. It was found that the chemical composition of the essential oil obtained from the white ginger contained 0.19% of a dried weight after 3 h of steam distillation. A total of 40 monoterpenoids (C10) and sesquiterpenoids (C15) secondary metabolite compounds were respectively detected in the oil.

Antimicrobial effect of the essential oil of Oregano against Listeria monocytogenes and Staphylococcus aureus.

The food industry uses chemical compounds to prevent the growth of bacteria and extend their shelf life. These substances are associated with toxic problems, the presence of chemical residues and antimicrobial resistance. Oregano essential oil has antimicrobial compounds such as thymol and carvacrol. The objective of the research was to evaluate the antimicrobial effect of oregano essential oil from the province of Concepción, Junín Region (Peru) against Listeria monocytogenes and Staphylococcus aureus. Oregano was taxonomically identified as O. vulgare. The essential oil was obtained by hydrodistillation and the profile of chemical compounds was determined by Gas Chromatography/Mass Spectrometry (GC-MS). The minimum inhibitory concentration (MIC) was determined by microdilution and the minimum bactericidal concentration (CMB) by agar planting Baird-Parker Agar was used for S. aureus and for L. monocytogenes the DNA hybridization method was used using the Gene Quencekit® L. monocytogenes. The GC-MS profile of oregano oil had 11.9% thymol and 1.7% carvacrol. The oil exhibited antimicrobial activity against S. aureus (CMI 2%, CMB 4%) and L. monocytogenes (CMI-4%, CMB-4%). The high percentage of CMI and CMB was due to the low concentration of carvacrol and thymol, however this oil can be used in the food industry as a natural antimicrobial and/or disinfectant.

Digging deeper - A new data mining workflow for improved processing and interpretation of high resolution GC-Q-TOF MS data in archaeological research

Gas chromatography-mass spectrometry profiling is the most established method for the analysis of organic residues, particularly lipids, from archaeological contexts. This technique allows the decryption of hidden chemical information associated with archaeological artefacts, such as ceramic pottery fragments. The molecular and isotopic compositions of such residues can be used to reconstruct past resource use, and hence address major questions relating to patterns of subsistence, diet and ritual practices in the past. A targeted data analysis approach, based on previous findings reported in the literature is common but greatly depends on the investigator’s prior knowledge of specific compound classes and their mass spectrometric behaviour, and poses the risk of missing unknown, potentially diagnostic compounds. Organic residues from post-prehistoric archaeological samples often lead to highly complex chromatograms, which makes manual chromatogram inspection very tedious and time consuming, especially for large datasets. This poses a significant limitation regarding the scale and interpretative scopes of such projects. Therefore, we have developed a non-targeted data mining workflow to extract a higher number of known and unknown compounds from the raw data to reduce investigator’s bias and to vastly accelerate overall analysis time. The workflow covers all steps from raw data handling, feature selection, and compound identification up to statistical interpretation.

Gas Chromatography-Mass Spectrometry Profiling of Volatile Compounds Reveals Metabolic Changes in a Non-Aflatoxigenic Aspergillus flavus Induced by 5-Azacytidine.

Aspergillus flavus is one of the most opportunistic pathogens invading many important oilseed crops and foodstuffs with such toxic secondary metabolites as aflatoxin (AF) and Cyclopiazonic acid. We previously used the DNA methylation inhibitor 5-azacytidine to treat with an AF-producing A. flavus A133 strain, and isolated a mutant (NT) of A. flavus, which displayed impaired abilities of AF biosynthesis and fungal development. In this study, gas chromatography–mass spectrometry (GC-MS) analysis was used to reveal the metabolic changes between these two strains. A total of 1181 volatiles were identified in these two strains, among which 490 volatiles were found in these two strains in vitro and 332 volatiles were found in vivo. The NT mutant was found to produce decreasing volatile compounds, among which most of the fatty acid-derived volatiles were significantly downregulated in the NT mutant compared to the A133 strain, which are important precursors for AF biosynthesis. Two antioxidants and most of the amino acids derived volatiles were found significantly upregulated in the NT mutant. Overall, our results reveal the difference of metabolic profiles in two different A. flavus isolates, which may provide valuable information for controlling infections of this fungal pathogen.

Profiling of Essential Oil Constituents in Ocimum Species

Ocimum species are herbaceous plants with great medicinal importance. Various tissues of the plants are being used in folk remedies for a variety of purposes. The pharmacologically active natural products present in essential oils in the Ocimum species belong to two major classes of natural compounds, viz. phenylpropanoids and terpenoids. In the present study, the essential oils from the inflorescence, leaf, and stem tissues of four major Ocimum species were hydro-distilled and analyzed. Gas chromatography–mass spectrometry profiling to unravel the phytomolecules and compositional quantification showed the occurrence of distinct tissue-based variability of phytomolecules. Phenylpropanoids such as eugenol and methyl chavicol were specifically found in the tissues of O. sanctum, O. gratissimum, and O. basilicum, respectively, whereas O. kilimandscharicum was distinct in possessing a terpenoid phytomolecule camphor predominantly in its tissues. The study also analyzed the uniqueness of the distribution of phytochemical constituents of essential oil in Ocimum species in tissue- and species-specific manner. Leaves were the major site of accumulation of essential oil, whereas inflorescence and stem also contained essential oil constituents albeit in low quantities.

GC-MS & preliminary screening profile of Cordia sinensis leaves – antiglycation, antifungal and insecticidal agents

Crude extracts and fractions of Cordia sinensis leaves were subjected to gas chromatography-flame ionisation detection (GC-FID), gas chromatography-mass spectrometry (GC-MS) analyses and preliminary screening for biological potentials using antibacterial, antifungal, phytotoxic, cytotoxic, insecticidal, antileishmanicidal and antiglycation bioassays. Overall thirty-one phytochemicals including three hydrocarbons, seven fatty acids, fifteen fatty acid esters, three terpenes, one each of phytosterol, terpenoid, and polyunsaturated aldehyde were identified. n-Hexadecanoic acid (13.2%), methyl hexadecanoate (9.0%), octadec-9Z-enoic acid (8.3%) and methyl octadec-9Z,12Z,15Z-trienoate (7.8%) were the main components. Presumably, this is a first report of twenty, thirteen and twenty phytochemicals from C. sinensis, Cordia and Boraginaceae, respectively. Moreover, ethyl acetate fraction exhibited significant insecticidal and antifungal activity against Sitophilus oryzae and Microsporum canis, respectively. Similarly, n-hexane fraction significantly inhibited (77.4%) advanced glycation end products in antiglycation assay. Conclusively, C. sinensis leaves with bioactive metabolites are a potential source for the development of insecticides, fungicides and pharmaceutically active antidiabetic drugs.

GC-MS Profile of Volatile Oils Extracted from Jatropha multifida L. using Hydrodistillation and Solvent-Free Microwave Extraction Methods

Volatile oils were extracted from the leaves of Jatropha multifida using solvent free microwave and hydrodistillation methods and the oils obtained were analyzed by gas chromatography-mass spectrometry (GC-MS). The major compound as observed is eucalyptol with 70.38 and 35.62 % for solvent-free microwave extraction (SME) and hydrodistillation extraction (HDE), respectively. The oil compositions were dominated by oxygenated compounds. Oxygenated monoterpenes were prevalent in contrast to monoterpenes hydrocarbons. The oils were also characterized by oxygenated sesquiterpenes (SME, 6.05 %; HDE, 7.34 %). This study may provide information on a suitable method of extraction of the essential oil for industrial application and may assist in the realization of the essential oil as a natural source of plant and animal food additives. These various bioactive compounds in the essential oil may partially justify their use in folklore medicine.

Impact of volatile cues on foraging response of egg larval parasitoid, Chelonus blackburni Cameron

Y-tube olfactometer study was carried out to observe the orientation response of egg-larval parasitoid Chelonus blackburni Cameron towards various concentrations of volatile cues emitted from three potato varieties and Phthorimaea operculella Zeller. Volatile cues were subjected to Gas Chromatography-Mass Spectrometry (GC-MS) profiling to identify the signaling molecules present in the pool of volatile cues. Out of 16 selected volatile cues concentrations obtained from plant and host insect sources, 10 cues acted as significant attractant for C. blackburni. Volatile cues emitted from Kufri Surya in vegetative stage were able to generate highest stimulation in C. blackburni. Among volatiles obtained from larval and adult stage of P. operculella, adult cues were found to be more efficient in the alteration of foraging behaviour of targeted parasitoid. GC-MS of targeted cues revealed the presence of fifteen saturated hydrocarbons ranging from C12 to C54; varying in concentrations. Study specified that C. blackburni preferred cues could be exploited to enhance the host searching efficacy during Integrated Pest Management releases.

Antioxidant activity optimization and GC-MS profile of aqueous extracts of Vernonanthura patens (Kunth) H. Rob. leaves

The temperature and extraction time of aqueous extracts of Vernonanthura patens (Kunth) H. Rob. (AEVP) leaves obtained by decoction were optimized for maximum recovery of DPPH radical scavenging activity, ABTS+ inhibition activity, total phenolic content (TPC) and total flavonoids content (TFC) using response surface methodology (RSM). A central composite design (CCD) of 13 experimental runs was applied and second order polynomial models were used to describe the responses of the assessed extraction parameters. The optimized conditions: 79.79 °C and 126.23 minutes were found using the composite desirability function. The scavenging activity of assessed extracts could be correlated mostly to the presence of malic acid, succinic acid, α-ketoglutaric acid, citric acid, m-hydroxybenzoic acid, caffeic acid, inositol, and β-amyrin detected by gas chromatography-mass spectrometry (GC-MS). These results have not been reported and support the potential application of AEVP as natural source of antioxidants.

PHYTOCHEMICAL, GAS CHROMATOGRAPHY-MASS SPECTROMETRY PROFILING AND FREE RADICAL SCAVENGING ACTIVITY OF EXOCARPOS LONGIFOLIUS (SANTALACEAE) EXTRACTS

Objective: The objectives of the study were to investigate phytochemical screening and gas chromatography-mass spectrometry (GC-MS) profiling of twigs and leaves of Exocarpos longifolius and its 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity.Methods: Phytochemical screening covering saponins, alkaloids, terpenoids, flavonoids, and tannins were carried out by standard methods. The free radical scavenging activity was performed by thin-layer chromatography - bioautography, followed by determining the IC50 values of active extracts. Chemical compounds of active extract were examined by gas chromatography/mass spectrometry.Results: The phytochemical screening revealed that all extracts have been shown to contain tannins and terpenoids, saponins were found in the methanol extract of twigs, and alkaloids were found in the ethyl acetate extracts of twigs and leaves, while flavonoids were found in the methanol extract and ethyl acetate extracts of twigs and leaves of E. longifolius. Ethyl acetate extract of twigs showed the best of IC50 value (15.65 μg/mL), while ethyl acetate extract of leaves and methanol extract of twigs have strong free radical scavenging activity which IC50 were 78.59 and 67.24 μg/mL, respectively. The GC-MS analysis of ethyl acetate extract of twigs has shown the presence of 12 identified compounds, and the main chemical compound is Stigmast-4-en-3-one (21.91%).Conclusions: The ethyl acetate extract of E. longifolius showed a very powerful free radical scavenging activity and revealed chemical compounds had been known to have biological activity. It might be used as a natural antioxidant.