Oil Of Rose-scented Geranium Research Articles

Biomass and volatile compounds of rose-scented geranium under various elicitors and cultivation systems

The current experiment was conducted to investigate the biomass and essential oil of rose-scented geranium when exposed to elicitors. The plants were grown either in a soil medium or a soilless cultivation system. Elicitors, namely methyl jasmonate (MeJA)(150 and 300 μM) and salicylic acid (SA)(0.75 and 1.5 mM), were used as foliar applications. The measurements included evaluating physiological and biochemical parameters, as well as essential oil content and concentration. Additionally, aromatic compounds of geranium were assessed using the headspace and GC/MS method. Photosynthetic capacity and biomass were significantly higher in soilless-grown plants compared to soil-grown plants, particularly in terms of chlorophyll content, stomatal conductance, and leaf area. The biomass produced in the soilless system was ten times greater than that in soil-grown plants. MeJA and SA enhanced growth parameters and essential oil production. The interaction between the cultivation system and elicitors had a significant impact on biochemical and physiological traits. Notably, the highest photosynthetic capacity, biomass, essential oil concentration, and yield were achieved in plants treated with 300 μM MeJA and 0.75 mM SA concentrations under soilless media. The main constituents of volatile components in soilless-grown plants were linalool, citronellal, citronellol, and citronellyl formate. On the other hand, geranial and geranyl propionate were the predominant compounds in plants grown in soil. The citronellol:geraniol ratio (C/G ratio) served as a qualitative indicator of essential oil compounds in rose-scented geranium. The highest value of this ratio and the greatest essential oil yield were obtained in soilless-grown plants treated with 300 μM MeJA.

Rose-scented Geranium (Pelargonium spp.) Plant Growth, and Essential Oil Yield and Composition as Affected by Paclobutrazol Application

Rose-scented geranium oil is extracted from the shoots (mostly the leaves) of the Pelargonium spp. through steam- or hydro-distillation. To extract less than 0.2% oil, farmers must transport and distil bulky herbage. This makes geranium oil production costly, and high time- and energy-consuming process. To investigate the effect of different paclobutrazol (PBZ) concentrations (0, 100, 200, 300 mg/L of water) on vegetative growth, and oil yield and composition of rose-scented geranium, three pot experiments were conducted. The experiments were conducted in a glasshouse of the University of Fort Hare, Alice, South Africa (located at 25°45′S and 28°16′E, an altitude of 520 m above sea level), between Oct. 2011 and May 2013. The treatments were arranged in a randomized complete block design (RCBD) in four replications. The PBZ was sprayed on the plants at 1 month of regrowth stage. Chlorophyll content increased with concentration of PBZ. The reduction of plant height in all PBZ-treated plants was significant, ranged between 18% and 33%. Plant canopy also reduced by 5% to 23%, and the differences were more noticeable in the plants grown between January and May (summer/autumn season), producing compact plants. Leaf area and internode length reduced as PBZ concentration increased. Paclobutrazol had no significant effect on leaf number, and essential oil yield and composition. This implies that, through applying PBZ, compacted (less bulky) rose-scented geranium could be produced without significant change in essential oil yield per plant and essential oil composition.

Influence of Gypsum and Farmyard Manure Application in Soil on Yield and Chemical Composition of Essential oil of Rose Scented Geranium (Pelargonium graveolens L'Herit.ex Ait.)

:A field experiment was conducted to evaluate the influence of farm yard manure (FYM) and gypsum application on the yield and chemical composition of essential oil of rose scented geranium. The herbage and essential oil yield of geranium was significantly increased (at 5 % level) by the combined application of FYM and gypsum along with recommended fertilizer application as compared to sole application of N, P and K fertilizer taken as control. The combined application of FYM and gypsum in soil was more effective to increase the herbage and essential oil yield of geranium by 35.4 % which was followed by the sole application of FYM (25.2 %) and gypsum (12.3 %) as compared to control. The chemical composition of the essential oil of geranium was affected differentially with the applied treatments. The content of citronellol, geraniol, linalool, citronellyl and geranyl formate in the essential oil of geranium were significantly increased by 48.9, 20.3, 62.3, 15.6 and 66.4 % respectively with the combined application of FYM and gypsum as compared to control but those were not significantly affected with the sole application of FYM and gypsum . The level of iso-menthone, trans-rose oxide were not affected but the content of cis-rose oxide was decreased and that of nerol and 10-epi-γ-eudesmol was increased in the essential oil of geranium with the application of FYM, gypsum and their combination as compared to control. The results suggest that the combined application of FYM and gypsum would be beneficial to obtain higher herb and essential oil yield of rose scented geranium with enhanced level of citronellol, geraniol along with their esters and other minor compounds like linalool, nerol, 10-epi-γ-eudesmol in the essential oil of geranium.

Essential oil of Algerian rose-scented geranium (Pelargonium graveolens): Chemical composition and antimicrobial activity against food spoilage pathogens

The aim of this study was to analyse the chemical composition of essential oil of rose-scented geranium (Pelargonium graveolens L.) growing in Algeria and to test the efficacy of the oil against food spoilage and food-borne pathogens.The chemical composition of the oil was analysed by Gas Chromatography-Mass Spectrometry (GC–MS). A total of 45 compounds representing 94.2% of the essential oil were identified. The main constituents were citronellol (30.2%), citronellyl formate (9.3%) and geraniol (7.6%).The antimicrobial activity of essential oil was evaluated against 23 food spoilage microorganisms in liquid and vapour phase at three different concentrations (10, 20 and 30μl/disc).The oil exhibited promising antibacterial effect against Gram positive more than Gram negative bacteria and provides a good inhibitory effect against Candida strains. Furthermore, the zone of inhibition increased with increasing oil concentration. Significantly higher antimicrobial activity was observed in the vapour phase. This is the first report on the antimicrobial properties of the essential oil of Algerian rose geranium.Our results suggest that rose-scented geranium oil could be used for the development of novel types of antibacterial agents to control food spoilage and food-borne pathogens.

Microbial and chemical sources of phosphorus supply modulate the yield and chemical composition of essential oil of rose-scented geranium (Pelargonium species) in sodic soils

Rose-scented geranium (Pelargonium sp.) is a highly valued aromatic crop. Its growth is limited by soil salinity and sodicity stress. Arbuscular mycorrhizal (AM) fungus, phosphate-solubilizing bacteria (PSB), and P fertilizers may enhance the growth and secondary metabolism in geranium plants. In this context, a pot experiment was conducted to study the effects of PSB, AM fungi (Glomus intraradices), and P fertilizer on the yield, chemical composition of essential oil, and mineral element acquisition of geranium. The dry matter yield of shoot and essential oil yield, and mineral element (P, K, Ca, Mg, Na, Fe, Cu, and Zn) uptake in shoot tissues of geranium were significantly increased by the inoculation with AM fungi, co-inoculation with AM fungi and PSB, and P fertilization as compared to control. While the co-inoculation of geranium with AM fungi and PSB significantly enhanced the content of the monoterpenes such as citronellol, geraniol, geranial, and a sesquiterpene (10-epi-γ eudesmol), the P fertilization only enhanced the content of a sesquiterpene, 10-epi-γ eudesmol in the volatile oil. We conclude that the co-inoculation of PSB and AM fungi could be the best natural alternative to phosphate fertilizers to enhance the yield and quality of essential oil from geranium plants grown in sodic soils.

Plant Shoot Age and Temperature Effects on Essential Oil Yield and Oil Composition of Rose-Scented Geranium (Pelargonium sp.) Grown in South Africa

A field experiment was conducted during 2005/2006 at the Experimental Farm of the University of Pretoria, South Africa to investigate the changes in herbage yield, oil yield and the variation in the concentration of the major components of rose-scented geranium. The essential oil was isolated by steam-distillation and the composition was determined by gas chromatography (GC). The results revealed that herbage yield increased over time in the first four (autumn/winter) and five (spring/summer) months of the respective harvesting cycles. The plants harvested in the spring/summer cycle had higher herbage yield and oil percentage than plants harvested in the autumn/winter cycle. The decrease in oil percentage was associated with low night temperatures in the autumn/winter cycle. The geraniol content decreased with decreasing night temperatures in autumn/winter while the citronellol content showed a tendency to increase. Geraniol followed a similar trend when regressed against plant shoot age in both experimental cycles. The decrease in geraniol content with respect to plant shoot age, therefore, increased the citronellol: geraniol ratio in both experimental cycles. The spring/summer harvesting season was superior to the autumn/winter season in all commercial aspects of rose-scented geranium oil production.

Antifungal Activity of Rose-Scented Geranium (Pelargonium Species) Essential Oil and its Six Constituents

Rose scented Geranium (Pelargonium species) leaf oil and six of its major constituents namely citronellol, linalool, geraniol, isomenthone, geranyl formate and citronellyl formate showed fungicidal properties against Candida albicans and Crytococcus neoformans, causing common fungal infections like candidiasis and cryptococosis in human beings. In terms of antifungal activity, citronellol was the most effective followed by geraniol, isomenthone, geranyl formate and citronellyl formate. The activity of pure oil seemed to differ from the constituents. The effect was observed both at 28 and 40C indicating temperature independent activity. Probably the antifungal activity is mediated through some mechanism other than membrane disruption and inhibition of cell division. The fungicidal activity was compared well with the standard antifungal drugs. Citronellol isolated from rose-scented geranium oil, therefore, holds promise for pharmaceutical uses.

Weed control in rose-scented geranium (Pelargonium spp).

Abstract: Field investigations were carried out during 1999 and 2000 to identify effective chemical/ cultural methods of weed control in rose-scented geranium (Pelargonium spp). The treatments comprised pre-emergence applications of oxyfluorfen (0.15, 0.20 and 0.25 kg AI ha(-1)) and pendimethalin (0.50, 0.75 and 1.00kg AI ha(-1)), successive hand weeding, hoeing and mulching using spent of lemon grass (at 5 tonnes ha(-1)) 45 days after planting (DAP), three hand-weedings 30, 60 and 90 DAP, weed-free (frequent manual weeding) and weedy control. Broad-leaf weeds were more predominant than grass and sedge weeds, accounting for 85.8% weed density and 93.0% weed dry weight in 1999 and 77.2% weed density and 93.9% weed dry weight in 2000. Unrestricted weed growth significantly reduced geranium oil yield, by 61.6% and 70.6% in 1999 and 2000, respectively. Pre-emergence application of pendimethalin (0.75-1.00 kgAI ha(-1)) or oxyfluorfen (0.25 kg AI ha(-1)), successive hand-weeding, hoeing and mulching and three hand-weedings were highly effective in reducing weed density and dry weight and gave oil yield comparable to the weed-free check. Application of oxyfluorfen (0.15 or 0.20 kg AI ha(-1)) and pendimethalin (0.50 kg AI ha(-1)) were less effective in controlling the weed species in geranium. None of the herbicides impaired the quality of rose-scented geranium oil measured in terms of citronellol and geraniol content.

Water soluble fractions of rose-scented geranium ( Pelargonium species) essential oil

The essential oil of rose-scented geranium ( Pelargonium species, family: Geraniaceae) obtained through steam or water plus steam distillation of shoot biomass is extensively used in the fragrance industry and in aromatherapy. During distillation, a part of the essential oil becomes dissolved in the distillation water (hydrosol) and is lost as this hydrosol is discarded. In this investigation, hydrosol was shaken for 30 min with hexane (10:1 proportion) and the hexane was distilled to yield `secondary' or `recovered' essential oil. The chemical composition of secondary oil was compared with that of `primary' oil (obtained directly by distilling shoot biomass of the crop). Primary oil accounted for 93.0% and secondary oil 7.0% of the total oil yield (100.2 ml from 100 kg green shoot biomass). Fifty-two compounds making up 95.0–98.5% of the primary and the secondary oils were characterized through gas chromatography (GC) and gas chromatography–mass spectroscopy (GC–MS). Primary oil was richer in hydrocarbons (8.5–9.4%), citronellyl formate (6.2–7.5%), geranyl formate (4.1–4.7%), citronellyl propionate (1.0–1.2%), α-selinene (1.8–2.2%), citronellyl butyrate (1.4–1.7%), 10- epi-γ-eudesmol (4.9–5.5%) and geranyl tiglate (1.8–2.1%). Recovered oil was richer in organoleptically important oxygenated compounds (88.9–93.9%), commercial rhodinol fraction (74.3–81.2%), sabinene (0.4–6.2%), cis-linool oxide (furanoid) (0.7–1.2%), linalool (14.7–19.6%), α-terpineol (3.3–4.8%) and geraniol (21.3–38.4%). Blending of recovered oil with primary oil is recommended to enhance the olfactory value of the primary oil of rose-scented geranium. Distillation water stripped of essential oil through hexane extraction can be recycled for distilling the next batch of rose-scented geranium.

Yield and Chemical Composition of Rose-Scented Geranium (Pelargonium Species) Oil at Different Times of Harvesting

A field experiment was conducted for six months covering rainy, autumn and spring seasons, to investigate the influence of time of harvesting on yield and quality of the oil of rose-scented geranium (Pelargonium sp.) cv. Bourbon, in the semi-arid tropical climate of south India. A diurnal fluctuation in oil yield was observed with a maximum at 12:00 noon (0.27%) and a minimum at 12:00 midnight (0.18%). The oil composition assessed by linalool (7.1–8.4%), isomenthone (7.0–8.1%), citronellol (22.2–23.3%), geraniol (20.6–25.2%), citronellyl formate (4.9–5.5%), geranyl formate (3.8–4.7%) and 10-epi-γ-eudesmol (5.0–7.4%) was not significantly affected by time of harvesting.

Essential Oil of Rose-scented Geranium (Pelargonium sp.) from Cuba

The essential oil obtained by hydrodistillation from the leaves of rose-scented geranium (Pelargonium sp.) grown in Cuba was analyzed by GC/MS. Fifty-four compounds were identified which constituted 95.5% of the oil. The major constituents were citronellol (25.6%), α-guaiene (7.2%) and caryophyllene oxide (14.7%)

First observation of little leaf disease and its impact on the yield and composition of the essential oil of rose-scented geranium (Pelargonium sp.)

Rose-scented geranium (Pelargonium sp.) plants infected with little leaf disease, probably caused by mycoplasma, were firstly observed during 1996–1998. The plants exhibited symptoms of reduced leaf/petiole size (little leaf), yellowing and bunching of leaves and cessation of plant growth, resulting in plant mortality. Plant parameters, viz. plant height, plant spread, number of branches, leaf size, leaf weight, etc., were adversely affected by little leaf disease, leading to significant reductions in shoot (49–70%), root (65–84%) and oil (67–91%) yields of diseased plants in comparison to healthy plants. Healthy plants recorded higher concentrations of geraniol, while little leaf disease-affected plants had higher percentages of isomenthone, citronellol, citronellyl formate, 10-epi-γ-eudesmol, citronellyl tiglate and geranyl tiglate. Copyright © 2000 John Wiley & Sons, Ltd.

Aberrations in the Composition of the Herb Oil of Rose-scented Geranium (Pelargonium Species)

Herb oils of rose-scented geranium cv. Bourbon distilled during summer (May) contained abnormally high concentrations of menthone (38.6%, 47.2%) or 10-epi-γ-eudesmol (22.0%) or citronellol (36.3%) in comparison to the oil produced during winter (citronellol 25.4%, geraniol 23.5%). Significant differences were observed among these oils for other components (linalool, isomenthone, geraniol, citronellyl formate and geranyl formate) also.

Yield and Chemical Composition of the Essential Oil of Rose-scented Geranium (Pelargonium species) Grown in the Presence and Absence of Weeds

The changes in herbage yield, essential oil yield and chemical composition of the essential oil of rose-scented geranium (Pelargonium sp.) cv. Bourbon were investigated in the presence and absence of weeds during different periods of crop growth. The crop, which was kept weed-free for the first 30 or 60 days after planting, or which was not kept weed-free for the first 90 or 120 days after planting, suffered greater yield losses (herbage yield 40.6–58.3%, oil yield 46.9–65.0%) than the crop which was kept weed-free for the first 90 or 120 days after planting or for the last 90 or 120 days before harvesting. Therefore, the rose-scented geranium crop should be kept weed-free, either during the first 90 days after planting or during the last 90 days before harvesting, to obtain high herbage and essential oil yields. The presence of weeds during different periods of crop growth decreased the concentrations of linalol (20.8–33.3%), isomenthone (4.8–12.0%), citronellol (1.8–14.9%) and citronellyl formate (4.3–20.3%) and increased the contents of geraniol (8.8–22.7%) and geranyl formate (10.0–50.0%) in the essential oil. The percentages of rose oxide and 10-epi-γ-eudesmol in the essential oil were not affected by either the presence or absence of weeds. © 1997 John Wiley & Sons, Ltd.

Changes in Chemical Composition of Rose-Scented Geranium (Pelargonium sp.) Oil during Storage

A comparison between properly stored and improperly stored (containing a small amount of water, half-filled in aluminum container and stored under ambient conditions) rose-scented geranium oil was made. It was found that the menthone, citronellol and citronellyl formate contents increased significantly under poor storage conditions, whereas linalool, geraniol, geranyl formate and lO-epi-γ-eudesmol contents decreased under poor storage conditions over the period of 6-24 months. When the oil was stored correctly, the concentrations of linalool, citronellol, citronellyl formate and 10-epi-γ-eudesmol did not vary markedly, while that of menthone increased slightly and those of geraniol and geranyl formate declined marginally. Correct storage conditions were defined as oil that has been dried over anhydrous sodium sulfate, filled up to the brim in an aluminum container or amber-colored bottle, tightly stoppered and stored under ambient conditions. No polymerization was observed in oils irrespective of storage conditions.

Composition of the Oil of Rose-Scented Geranium (Pelargonium sp.) Grown Under the Semiarid Tropical Climate of South India

ABSTRACT Essential oil of rose-scented geranium (Pelargonium sp.) cultivated under the semiarid tropical climate of Andhra Pradesh, South India has been examined by capillary GC and GC/MS. The oil possessed a composition similar to the African-type geranium because of the presence of a higher concentration of 10-epi-γ-eudesmol (3.8–4.2%) than of guaia-6, 9-diene (0.13–0.15%).

Origin of the rose-scented Pelargonium cultivar grown on Réunion Island

The Pelargonium cultivar grown on Reunion for the production of rose-scented geranium oil is locally known as the cv. Rose. The origin of the cv. Rose is demonstrated by comparing its morphology, chromosome number and essential oil with those of putative ancestral species. It is concluded that P. capitatum (L.) L’Herit. and P. radens H.E. Moore can be considered as the parent species. A comparison of the characters of the cv. Rose and those of artificial hybrids between P. capitatum and P. radens , confirmed the assumption.