Antioxidant and antibacterial activities of the leaf essential oil and its constituents furanodienone and curzerenone from Lindera pulcherrima (Nees.) Benth. ex hook. f.

BACKGROUND: Lindera pulcherrima (Nees.) Benth. ex Hook. f. (Family: Lauraceae), an evergreen shrub, is an important medicinal plant distributed in temperate Himalayan regions. The leaves and bark are used as spice in cold, fever, and cough. MATERIALS AND METHODS: In this study, the terpenoid composition, antioxidant, and antibacterial activities of the leaf essential oil and its major constituents are being analyzed. CONCLUSION: The in vitro antioxidant activity showed a potent free radical scavenging activity for the essential oil as evidenced by a low IC(50) value for DPPH radical followed by furanodienone (0.087 ± 0.03 and 1.164 ± 0.58 mg/ml respectively) and the inhibition of lipid peroxidation for the oil and furanodienone also followed the same order (IC(50) 0.74 ± 0.13 and 2.12 ± 0.49 mg/ml, respectively). The oil and the constituents were also tested against three Gram negative (Escherichia coli, Salmonella enterica enterica, and (Pasturella multocida) and one Gram positive (Staphylococcus aureus) bacteria. The essential oil was effective against S. aureus (IZ = 19.0 ± 0.34; MIC 3.90 µl/ml) while furanodienone showed potent activity against E. coli and S. enterica enterica (IZ = 18.0 ± 0.14 and 16.0 ± 0.10 respectively). On the other hand, curzerenone was found to be slightly effective against E. coli (IZ = 10.8 ± 0.52). The MIC value of the essential oil was least against S. aureus (MIC = 3.90 µl/ml) and that of furanodienone against E. coli (MIC = 3.90 µl/ml).

Isoiridomyrmecin rich essential oil from Nepeta erecta Benth. and its antioxidant activity.

The essential oil composition of the aerial parts of Nepeta erecta Benth. (Family: Lamiaceae) from Uttarakhand, India was analysed by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). A total of 34 constituents were identified representing 94.6% of the oil composition. Oxygenated monoterpenes (74.0%) constituted the major proportion of the oil, dominated by isoiridomyrmecin (70.6%) as a single major constituent. Other significant constituents were caryophyllene oxide (9.6%), ß-Bourbonene (2.0%), humulene epoxide II (1.7%) and linalool (1.0%). The in vitro antioxidant activity (AOA) was assessed using ß-Carotene bleaching assay, reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and inhibition of lipid peroxidation methods. The oil was found to exhibit AOA by inhibiting ß-Carotene bleaching (54.6 ± 2.52%) and by scavenging DPPH free radical (IC(50) = 0.74 ± 0.12 mg mL(-1)). The AOA of the essential oil of N. erecta and its major compound isoiridomyrmecin has not been reported so far.

Antioxidant and antibacterial activities of the leaf essential oils of Himalayan Lauraceae species.

The leaf essential oils from seven Himalayan Lauraceae species viz. Neolitsea pallens, Lindera pulcherrima, Dodecadenia grandiflora, Persea duthiei, Persea odoratissima, Persea gamblei and Phoebe lanceolata exhibited potent antioxidant and antibacterial activities. The in vitro antioxidant activity was assessed by using beta-carotene bleaching assay, reducing power, DPPH radical scavenging and inhibition of lipid peroxidation methods. The oils of D. grandiflora and L. pulcherrima showed a potent free radical scavenging activity as evidenced by low IC(50) value for DPPH radical (0.032 mg/ml and 0.087 mg/ml, respectively) and inhibition of lipid peroxidation (in between IC(50)=0.44 mg/ml and IC(50)=0.74 mg/ml, respectively). The oils were tested against three Gram negative (Escherichia coli, Salmonella enterica enterica and Pasturella multocida) and one Gram positive (Staphylococcus aureus) bacteria at different concentrations using disc diffusion and tube dilution methods. The inhibition zones (IZ) and MIC values for bacterial strains were in the range of 8.7-22.0mm and 3.90-31.25 microl/ml, respectively.

Chemical diversity in Himalayan Elsholtzia species.

The terpenoid composition of essential oils from the leaves of five Elsholtzia species, viz., E. eriostachya Benth., E. cristata Willd., E. polystachya Benth., E. flava Benth., and E. pilosa Benth., collected from the Himalayan region (India), was examined by GC, GC/MS, and NMR analyses. Comparison of the results with previous reports revealed new chemotypes. Cluster analysis was carried out in order to discern the similarities and differences within the essential-oil compositions at their subspecies/chemotype level. Based on the major constituents of the essential oils, six chemical groups were obtained.

Terpenoid diversity in the leaf essential oils of Himalayan Lauraceae species.

The leaf terpenoid compositions of nine Lauraceae species, viz., Neolitsea pallens, Lindera pulcherrima, Dodecadenia grandiflora, Persea duthiei, Persea odoratissima, Persea gamblei, Phoebe lanceolata, Cinnamomum tamala, and Cinnamomum camphora, collected from the Himalayan region (India) were examined by GC, GC/MS, and NMR analyses in order to determine the similarities and differences among their volatile constituents. Furano-sesquiterpenoids were the principal constituents of N. pallens, L. pulcherrima, and D. grandiflora. (E)-Nerolidol, limonene, beta-pinene, and alpha-pinene were the major constituents of P. duthiei; alpha-pinene, sabinene, and beta-caryophyllene were predominant in P. odoratissima, while the oils of P. gamblei and P. lanceolata possessed beta-caryophyllene as common major constituent. C. camphora and C. tamala were marked by the presence of camphor and cinnamaldehyde, respectively. Cluster analysis of the oil composition was carried out in order to discern the differences and similarities within nine species of six genera of Lauraceae.

Oesophageal carcinoma--a study of risk factors (emphasis on nutrition) in a teaching hospital of Kumaon region of Uttarakhand.

BACKGROUND: Cancer oesophagus is common in India and is the third leading cause of cancer death in males and fourth in females. Various factors are responsible for it and present study was undertaken to study the various risk factors with stress on nutritional factors associated with it. METHODS: Ninety-four cases of oesophagus cancer and matched equal number of healthy individuals (control) constituted the study. They were assessed for their dietary pattern during the preceding 10-15 years with the help of standard food frequency questionnaire method. Information regarding consumption of alcohol, smoking and tobacco chewing with or without betel leaf was taken in detail. RESULTS: Seven hundred and eighty upper GI endoscopy revealed 94 (12.05%) cases of oesophageal carcinoma. Histopathology revealed squamous cell carcinoma in 87 cases (92.50%), adenocarcinoma in 6 cases (6.30%) and one with mixed picture of adenocarcinoma and squamous cell carcinoma. Sixth (36.17%) and 7th (23.40%) decade of persons were mainly affected with male to female ratio of 2.1:1. They were mostly of lower socio-economic (82.90%) status. Various risk factors came across were less consumption of green and leafy vegetables and fruits and consuming more spicy fried and hot food and beverages. Increased risk was seen more often with consumption of alcohol (neat and without or less salad and snacks), smoking beedi and cigarette, and tobacco chewing with or without betel leaf. It is directly related to amount, frequency, mode and duration of use. CONCLUSIONS: Malignancies in general are result of multiple factors and interaction of several environmental factors. One factor cannot be blamed but combination of factors increases the risk of oesophageal carcinoma. Nutritional factor is also one of the major contributing factor increasing the risk of oesophagus cancer.