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Cymbopogon species essential oil (EO) carries significant importance in pharmaceuticals, aromatherapy, food, etc. The chemical compositions of Cymbopogon spp. Viz. Cymbopogon winterianus (citronella) Cymbopogon citratus (lemongrass), and Cymbopogon martini (palmarosa) were analyzed by gas chromatography−mass spectrometry (GC-MS), enantiomeric distribution by chiral GC-MS, and antimicrobial activities of some selected pure major compound and root and leaves EOs of citronella. The EO of leaves of Cymbopogon spp. showed comparatively higher yield than roots or other parts. Contrary to citral (neral and geranial) being a predominant compound of Cymbopogon spp., α-elemol (53.1%), α-elemol (29.5%), geraniol (37.1%), and citral (90.4%) were detected as major compounds of the root, root hair with stalk, leaf, and root stalk with shoot of citronella EO, respectively. Palmarosa leaves’ EO contains neral (36.1%) and geranial (53.1) as the major compounds. In the roots of palmarosa EO, the prime components were α-elemol (31.5%), geranial (25.0%), and neral (16.6%). Similarly, lemongrass leaves’ EO contains geraniol (76.6%) and geranyl acetate (15.2%) as major compounds, while the root EO contains a higher amount of geraniol (87.9%) and lower amount of geranyl acetate (4.4%). This study reports for the first time chiral terpenoids from Cymbopogon spp. EOs. Chiral GC-MS gave specific enantiomeric distributions of nine, six, and five chiral terpenoids in the root, root stalk with a shoot, and leaves of citronella EOs, respectively. Likewise, four and three chiral terpenoids in the root and leaves of lemongrass oil followed by two chiral terpenoids in the leaves and root of palmarosa EOs each. Additionally, the root and leaves’ EOs of citronella exhibit noticeable activity on bacteria such as Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes and fungus such as Candida albicans, Microsporum canis, and Trichophyton mentagrophytes. So, geranial-, neral-, geraniol-, and citronellal-rich EOs can be used as an alternative antimicrobial agent.

This study was conducted to examine the chemical constituents of Origanum majorana L. essential oils (EOs) that originate in Nepal, as well as their biological activities, antioxidant properties, and enantiomeric compositions. The EOs were extracted by the hydro-distillation method using a Clevenger-type apparatus and their chemical compositions were determined through gas chromatography and mass spectrometry (GC-MS). Chiral GC-MS was used to evaluate the enantiomeric compositions of EOs. The minimum inhibitory concentrations (MICs) of the essential oils were determined by the micro-broth dilution method, and the antioxidant activity was evaluated by the 2,2-diphenyl-1-picrylhydrazyl scavenging assay and ferric-reducing antioxidant power (FRAP). GC-MS analysis showed the presence of 50 and 41 compounds in the EO samples, (S 1 ) and (S 2 ), respectively, representing the Kathmandu and Bhaktapur districts. The oxygenated monoterpenoids, along with terpinen-4-ol, were predominant constituents in both EO samples. However, the EOs from two locations showed some variations in their major components. The chiral terpenoids for two EO samples of marjoram have also been reported in this study in an elaborative way for the first time in accordance with the literature review. A hierarchical cluster analysis based on the compositions of EOs with 50 compositions reported in the literature revealed at least 5 different chemotypes of marjoram oil. The antioxidant activity for the sample (S 2 ) was found to be relatively moderate, with an IC 50 value of 225.61 ± 0.05 μg/mL and an EC 50 value of 372.72 ± 0.84 µg/mL, as compared to the standard used. Furthermore, with an MIC value of 78.1 µg/mL, the EO from sample (S 2 ) demonstrated effective antifungal activity against Aspergillus niger and Candida albicans . Moreover, both samples displayed considerable antimicrobial activity. The results suggest that EOs of Origanum majorana possess some noteworthy antimicrobial properties as well as antioxidant activity, and hence can be used as a natural preservative ingredient in the food and pharmaceutical industries.

Citrus species of plants are among the most commercially cultivated crops, mainly for their fruit. Besides, the generally consumed flesh inside the fruit, the peel is quite important too. Essential oils extracted from the peel have a history of being used by humankind for centuries. These essential oils are rich in antioxidants and antimicrobial agents. Comparative investigation of volatile constituents, and antioxidant and antimicrobial activities were undertaken. The essential oils were evaluated through gas chromatography-mass spectrometry (GC-MS), and enantiomeric composition by chiral GC-MS. Similarly, the antioxidant properties were evaluated by 2,2-diphenyl-1-picrylhydrazyl scavenging assay, and antimicrobial activities were assayed using the disk diffusion method. The highest extraction yield of 1.83% was observed in Citrus sinensis Osbeck. GC-MS analysis showed limonene (63.76-89.15%), γ-terpinene (0.24-6.43%), β-pinene (0.15-6.09%), linalool (0.35-3.5%), sabinene (0.77-2.17%), myrcene (0.74-1.75%), α-terpineol (0.28-1.15%), and α-pinene (0.2-0.58%) as the major constituents of the essential oil of the Citrus species studied. For the first time, through our study, chiral terpenoids have been observed from Citrus grandis Osbeck essential oil. The order of antioxidant activity is as follows: Citrus grandis Osbeck red flesh > Citrus reticulata Blanco > Citrus sinensis Osbeck > Citrus grandis Osbeck white flesh. Except for Citrus grandis Osbeck white flesh (52.34 µL/mL), all samples demonstrated stronger antioxidant activities than those of the positive control, quercetin (5.60 µL/mL). Therefore, these essential oils can be used as a safe natural antioxidant to prevent product oxidation. Likewise, citrus peel essential oil showed antimicrobial activity against tested bacterial strains, albeit marginal.

Rhododendron anthopogon D. Don., A small compact Himalayan shrub growing in Nepal, is a known medicinal plant used to treat sore throat, colds, blood disorders, bone disease, potato allergies, and vomiting, and to relieve liver disorders, headaches and back pain. The present study investigated the chemical composition and bioactivities of the leaf essential oil from R. anthopogon from Dhankuta, Nepal. The essential oil from leaves was obtained by hydrodistillation and a detailed chemical analysis was conducted by gas chromatography - mass spectrometry.(GC-MS). The enantiomeric distribution of monoterpenoid components was determined using chiral gas chromatography and represents the first chiral examination of R. anthopogon essential oil. The essential oil was screened for antimicrobial activity using the microbroth dilution test, and for cytotoxic activity against MCF-7, MDA-MB-231, and 5637 using the MTT assay. A total of 70 volatile componeits were identified from the essential oil. The major components were α-pinene (21.5%), δ-cadinene (13.8%), β-pinene (9.5%), limoiene (5.9%), δ-amorphene (4.6%), α-muurolene (4.5%), and (E)-daryophyllene (3.2%) with other minor constituents (< 3%). The essential oil showed marginal antibacterial and.cytotoxic activities, but no antifungal effects.

The aerial parts of Lantana camara L. were collected from three different geographical locations: Artemisa (Cuba), Biratnagar (Nepal), and Sana'a (Yemen). The essential oils were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. A cluster analysis of 39 L. camara essential oil compositions revealed eight major chemotypes: β-caryophyllene, germacrene D, ar-curcumene/zingiberene, γ-curcumen-15-al/epi-β-bisabolol, (E)-nerolidol, davanone, eugenol/alloaromadendrene, and carvone. The sample from Cuba falls into the group dominated by (E)-nerolidol, the sample from Nepal is a davanone chemotype, and the sample from Yemen belongs to the β-caryophyllene chemotype. The chemical composition of L. camara oil plays a role in the biological activity; the β-caryophyllene and (E)-nerolidol chemotypes showed antimicrobial and cytotoxic activities., (© 2016 Verlag Helvetica Chimica Acta AG, Zürich.)

The essential oil from the aerial parts of Blumea lacera collected from Biratnagar, Nepal, has been obtained by hydrodistillation and analyzed by gas chromatography - mass spectrometry. The major component from the oil, (Z)-lachnophyllum ester, was isolated by preparative silica gel chromatography. B. lacera oil was dominated by (Z)-lachnophyllum ester (25.5%), (Z)-lachnophyllic acid (17.0%), germacrene D (11.0%), (E)-β-farnesene (10.1%), bicyclogermacrene (5.2%), (E)-caryophyllene (4.8%), and (E)-nerolidol (4.2%). Also detected in the oil were (E)-lachnophyllic acid (3.3%) and (E)-lachnophyllum ester (1.7%). (Z)-Lachnophyllum ester exhibited cytotoxic activity against MDA-MD-231, MCF-7, and 5637 human tumor cells, as well as antibacterial and antifungal activity.

The essential oil of Matricaria chamomilla, collected from Nepal, was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The major components in Nepalese chamomile oil were (E)-β-famesene (42.2%), α-bisabolol oxide A (22.3%), (E,E)-α-famesene (8.3%), cis-bicycloether (5.0%), α-bisabolol oxide B (4.5%), and α-bisabolone oxide A (4.0%). A cluster analysis based on the chemical compositions of 48 samples of chamomile oil reported in the literature has revealed seven chemotypes, and the oil from Nepal represents the (E)-β-farnesene chemotype. The chamomile oil was screened for antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger, and toxicity toward MCF-7 breast tumor cells, Artemia salina, Chaoborus plumicornis, Caenorhabditis elegans, and Drosophila melanogaster.

The essential oil from the dried rhizome of Nardostachys grandiflora, collected from Jaljale, Nepal, was obtained in 1.4% yield, and a total of 72 compounds were identified constituting 93.8% of the essential oil. The rhizome essential oil of N. grandiflora was mostly composed of calarene (9.4%), valerena-4,7(11)-diene (7.1%), nardol A (6.0%), 1(10)-aristolen-9β-ol (11.6%), jatamansone (7.9%), valeranal (5.6%), and cis-valerinic acid (5.7%). The chemical composition of N. grandiflora rhizome oil from Nepal is qualitatively very different than those from Indian, Chinese, and Pakistani Nardostachys essential oils. In this study we have evaluated the chemical composition and biological activities of N. grandiflora from Nepal. Additionally, 1(10)-aristolen-9β-ol was isolated and the structure determined by NMR, and represents the first report of this compound from N. grandiflora. N. grandiflora rhizome oil showed in-vitro antimicrobial activity against Bacillus cereus, Escherichia coli, and Candida albicans (MIC = 156 μg/mL), as well as in-vitro cytotoxic activity on MCF-7 cells.

The essential oils from the leaves, fruits, roots, and stems of Solanum xanthocarpum, growing wild in Nepal, have been obtained and analyzed by gas chromatography-mass spectrometry. The fruit volatiles were dominated by benzyl benzoate (21.7%) and (E,E)-geranyl linalool (12.6%); heptacosane (20.0%) was the major component of the leaf oil; the stem oil was dominated by palmitic acid (28.9%), heptacosane (12.8%) and linoleic acid (10.1%); while solavetivone (22.9%), palmitic acid (21.0%), and linoleic acid (8.2%) were the major components of the root essential oil. There do not seem to be any common phytochemical taxonomic markers in the essential oils of Solanum spp; the chemical diversity observed in this genus mirrors the taxonomic diversity.

The essential oil from the parasitic vine Cuscuta reflexa Roxb., collected from Kirtipur, Kathmandu, Nepal, was obtained by hydrodistillation and analysed by gas chromatography-mass spectrometry. From a total of 62 peaks, 61 compounds were identified in the oil, accounting for 99.6% of the oil. The majority of the essential oil was dominated by the relatively rare component cis-3-butyl-4-vinylcyclopentane (26.4%). The oil also contained substantial amounts of limonene (5.1%) and (E)-nerolidol (9.5%). Biological screening for antimicrobial activities did not show appreciable activity against either Gram-positive (Bacillus cereus and Staphylococcus aureus) or Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. However, marginal activity against Aspergillus niger was observed (minimum inhibitory concentration = 313 μg/mL).

The essential oils from the leaves of Juglans regia, collected from Kathmandu, Nepal, and Juglans nigra from Huntsville, Alabama, USA, were obtained by hydrodistillation and analyzed by GC-MS. A total of 69 compounds were identified in the J. regia oil, accounting for 99.0% of the eluting components of the oil while three different samples of J. nigra were analyzed identifying a total of 99.3%, 99.4% and 99.7% of the oils. The leaf essential oil of J. regia was dominated by the aromatic compounds eugenol (27.5%) and methyl salicylate (16.2%), and the sesquiterpenes germacrene D (21.4%) and (E)-beta-farnesene (8.2%). The essential oils from three different samples of. J. nigra contained (E)-caryophyllene (17.3%-20.4%) and germacrene D (7.1%-22.5%) with smaller amounts of juglone (1.0%-8.8%), alpha-hydrojuglone (1.0-9.5%), and delta-cadinene (3.8%-8.7%). J. regia leaf oil, devoid of juglone, showed allelopathic activity, while J. nigra leaf oil was less phytotoxic. The presence of eugenol and methyl salicylate in the leaves of J. regia are consistent with the traditional uses of this plant to treat toothache, rheumatism, and fungal infections.

Four essential oils from the leaf (P23) and rhizomes (P19, P22, P24) of Acorus calamus L., collected from various parts of Nepal, were obtained by hydrodistillation and analyzed by GC-MS. From a total of 61 peaks, 57 compounds were identified among the four essential oils accounting for 94.3%, 96.2%, 97.6%, and 94.1% of the oils, respectively. All of the essential oils were dominated by (Z)-asarone (78.1%-86.9%). The essential oils also contained (E)-asarone (1.9%-9.9%) and small amounts of gamma-asarone (2.0-2.3%), (Z)-methyl isoeugenol (1.5-2.0%), and linalool (0.2-4.3%). Allelopathic testing of the rhizome oil showed inhibition of seed germination of Lactuca sativa and Lolium perenne with IC50 values of 450 and 737 microg/mL, respectively. The rhizome essential oil demonstrated stronger seedling growth inhibition of L. perenne than of L. sativa, however. The rhizome oil also showed notable brine shrimp lethality (LC50 = 9.48 microg/mL), cytotoxic activity (92.2% kill on MCF-7 cells at 100 microg/mL), and antifungal activity against Aspergillus niger (MIC = 19.5 microg/mL).

The essential oils from the leaves of Artemisia dubia, A. indica, and A. vulgaris growing wild in Nepal were obtained by hydrodistillation and analyzed by GC-MS. The major components in A. dubia oil were chrysanthenone (29.0%), coumarin (18.3%), and camphor (16.4%). A. indica oil was dominated by ascaridole (15.4%), isoascaridole (9.9%), trans-p-mentha-2,8-dien-1-ol (9.7%), and trans-verbenol (8.4%). The essential oil of Nepalese A. vulgaris was rich in alpha-thujone (30.5%), 1,8-cineole (12.4%), and camphor (10.3%). The essential oils were screened for phytotoxic activity against Lactuca sativa (lettuce) and Lolium perenne (perennial ryegrass) using both seed germination and seedling growth, and all three Artemisia oils exhibited notable allelopathic activity. A. dubia oil showed in-vitro cytotoxic activity on MCF-7 cells (100% kill at 100 microg/mL) and was also marginally antifungal against Aspergillus niger (MIC = 313 microg/mL). DFT calculations (B3LYP/6-31G*) revealed thermal decomposition of ascaridole to be energetically accessible at hydrodistillation and GC conditions, but these are spin-forbidden processes. If decomposition does occur, it likely proceeds by way of homolytic peroxide bond cleavage rather than retro-Diels-Alder elimination of molecular oxygen.

The essential oils from the seed and rind of Amomum subulatum Roxb. (collected from Nepal) were obtained by hydrodistillation and analyzed by GC-MS. A total of 87 components were identified among the two essential oils accounting for 99.1%, and 99.0% of the oils, respectively. The two essential oils were dominated by the monoterpenoids 1,8-cineole (60.8% and 39.0%), alpha-pinene (6.4% and 4.8%), beta-pinene (8.3% and 17.7%), and alpha-terpineol (9.8% and 12.3%). Allelopathic testing of the seed essential oil showed an inhibition of seed germination of Lactuca sativa and Lolium perenne, with IC50 values of 1583 and 1674 microg/mL, respectively. The seed essential oil demonstrated a stronger seedling growth inhibition of L. perenne than of L. sativa. A. subulatum seed and rind oils also showed moderate brine shrimp lethality (LC50 = 28.1 +/- 3.0 and 15.0 +/- 9.0 microg/mL, respectively). The seed and rind oils were only marginally cytotoxic (20% and 30%% kill on MCF-7 cells at 100 microg/mL, respectively), and antibacterial (MIC > or = 313 microg/mL), but A. subulatum rind oil was appreciably active against the fungus Aspergillus niger (MIC = 19.5 microg/mL). The essential oils of A. subulatum were also screened for nematocidal activity against Caenorhabditis elegans and insecticidal activity against the fruit fly (Drosophila melanogaster) and the red imported fire ant (Solenopsis invicta x richteri). The seed oil was only marginally toxic to the fire ant (LC50 = 1500 microg/mL), but moderately toxic to the nematode and the fruit fly (LC50 = 341 and 441 microg/mL, respectively).

From July 1998 to July 1999, 45 cases of acute renal failure were treated at Bir Hospital, Kathmandu. Out of which 24 were male and 21 were female. Age ranged from 11 months to 84 years with mean age being 35 years and 9 cases were below 10 years. Four cases with pre-renal azotaemia and twenty five cases of acute tubular necrosis (ATN) accounted for 64% of all cases. These were due to gastroenteritis 10, sepsis 6, post surgical 1, trauma 1 and obstretical complications 5. Multiple hornet stings were responsible for acute renal failure in 3 cases, acute urate nephropathy in 1 case and miscellaneous causes in 2 cases. Glomerulonephritis / vasculitis accounted for 17.7%, acute interstitial nephritis 4.4%, haemotytic uraemic syndrome (HUS) 6.6%, and post renal azotaemia in 6.6% of all cases. Mean serum creatinine was 8 mg/dl, mean blood urea 190 mg/dl. Eight cases were treated only conservatively, eighteen received haemodialysis, fourteen received peritoneal dialysis, three received both and two refused for dialysis. Average duration of hospital stay was 13.6 days. Out of the forty-five cases twenty-nine recovered normal renal function, ten expired, two recovered partially, two progressed to chronic renal failure and two left against medical advice. Overall mortality was 22.2%. Common causes of acute renal failure in our setting were gastroenteritis (22%) and sepsis (20%). HUS was exclusively seen in children following bacillary dysentery. Multiple hornet stings is an important cause of acute renal failure in our country.