Alba Oil Research Articles

Antimycobacterial Activity of Essential Oils from Bulgarian Rosa Species Against Phylogenomically Different Mycobacterium tuberculosis Strains

In this study, we aimed to assess the activity of the essential oils from four Bulgarian oil-bearing roses Rosa damascena Mill., R. alba L., R. centifolia L., and R. gallica L., on the reference strain Mycobacterium tuberculosis H37Rv and clinical M. tuberculosis strains of the Beijing and Latin-American Mediterraneum genotypes. The chemical composition of the essential oils was determined by gas chromatography (GC-FID/MS). Minimal inhibitory concentrations (MIC) were determined using the resazurin method. R. alba oil showed the highest inhibitory activity when tested on all strains of different phylogenetic origins with MIC in the range of 0.16–0.31 mg/mL, while R. gallica oil was the least active (MIC 0.62–1.25 mg/mL). The obtained results show heterogeneity of rose oil action on different mycobacterial strains and we hypothesize that the combined level of geraniol and nerol is a key factor that underlies the antimycobacterial action of the rose oils. Strain Beijing 396 was relatively more susceptible to the rose oils probably due to multiple and likely deleterious mutations in its efflux pump genes. Two clinical MDR strains have likely developed during their previous adaptation to anti-TB drugs certain drug tolerance mechanisms that also permitted them to demonstrate intrinsic tolerance to the essential oils. Further research should investigate a possible synergistic action of the new-generation anti-TB drugs and the most promising rose oil extracts on the large panel of different strains.

Antifungal Activity of Cyperus articulatus, Cyperus rotundus and Lippia alba Essential Oils against Aspergillus flavus Isolated from Peanut Seeds.

Aspergillus flavus is a cosmopolitan saprophytic fungus that infests several foodstuffs and is associated with adverse effects in humans. In Senegal, significant losses of groundnut production are mainly due to contamination caused by this species. This study evaluated in vitro antifungal activities of Cyperus articulatus, Cyperus rotundus and Lippia alba essential oils against A. flavus isolated from peanut seeds. Essential oils obtained by hydrodistillation of rhizomes of the two Cyperus species and leaves of L. alba were analyzed with GC-DIF and GC-MS. The essential oil yields from C. articulatus, C. rotundus and L. alba were 1.1%, 1.3% and 1.7%, respectively. These three samples had the following chemotypes: (i) mustakone (21.4%)/eudesma-4(15)-7-dien-1β-ol (8.8%)/caryophyllene oxide (5.9%), (ii) caryophyllene oxide (25.2%)/humulene epoxyde 2 (35.0%) and (iii) geranial (46.6%)/neral (34.6%). The three oils tested inhibited the growth of A. flavus at concentrations between 100 and 1000 ppm. The L. alba oil was the most effective with total clearance of A. flavus on PDA. For the essential oils of C. rotundus (93.65%) and C. articulatus (78.11%), the highest inhibition rates were obtained with a 1000 ppm dose. Thus, L. alba oil could be used safely as an effective protector of groundnuts against A. flavus.

Multifrequency Ultrasound-Based Predictive Method for Biodiesel Production

Fossil fuel price continuous growth invites to look for alternative solutions to fuel for internal combustion engines. One of the most accepted options is biodiesel. In the present study, the multifrequency ultrasound-assisted synthesis of Sinapis alba oil biodiesel has been tested. For this purpose, an ultrasonic probe working at 20 kHz and an ultrasonic reactor with interchangeable transducers of discrete frequencies (195 kHz, 578 kHz, 861 kHz and 1136 kHz) have been used. For the probe, a multi-response optimisation has been carried out, setting methanol-to-oil molar ratio at 5.5:1. Optimal results were provided by 1.42 percentage weight (wt%) of catalyst after approx. 10 min of ultrasonication. In case of transducers, oil-to-biodiesel conversion needed an ultrasonication time of 15 min. Overall, when ultrasound frequency increases, oil-to-biodiesel conversion slightly improves. In conclusion, this work provides a predictive method to produce biodiesel under ultrasonication conditions, at different frequencies, in batch mode. Resulting biodiesel meets European standard requirements.

Levels of Expression of Hsp70 and iNOS and Effect of Artemisia Sieberi (A. herba-alba) on Activity of Hypothalamic-Pituitary-Thyroid (HPT) Axis in Diabetic Rats

This work was carried out to evaluate levels of expression of the Heat Shock Protein 70 (Hsp70) and inducible nitric oxide synthase (iNOS) biomarkers in extracts of Artemisia sieberi (A. herba-alba) and their impacts on the activity of hypothalamic-pituitary-thyroid (HPT) axis in diabetic rats. 50 rats were separated into five experimental groups: a normal control group, a positive control group treated with dilute A. herba alba (AHE) oil extract, a diabetic non-treated group, a diabetic group treated with AHA extract, and a diabetic group treated with Metformin. Results: Orally administered 8.1 mg/kg body weight (BW) of dilute AHA oil and 14.2 mg/kg BW of Metformin were administered for 6 weeks. Serum triiodothyronine (T3) levels decreased significantly in diabetic rats and increased significantly in the rats treated with the dilute AHA oil. Furthermore, no significant differences were observed in thyroid gland Hsp70 expression between the diabetic and non-diabetic rats. Metformin and dilute AHA oil treatments significantly increased the expression of Hsp70 in the thyroid gland. The results also demonstrated that diabetes significantly increased the rate of iNOS expression in the thyroid gland. Treatment with Metformin and dilute AHA oil significantly reduced the expression of iNOS in the thyroid gland. These results suggest that dilute AHA oil plays a role in the peripheral regulation of thyroid function and provide empirical evidence that it contributes to the stimulation or improvement of thyroid function.

<i>Sinapis alba</i> ln Status Epilepticus: A Preclinical Study

In this study, the anti-convulsant effect of Sinapis alba seed oil and its combination with sodium valproate was evaluated in Wistar albino rats using the lithium-pilocarpine Status Epilepticus (SE) model. The experimental groups included: Group I - normal control; Group II - disease control; Group III - Sinapis alba seed oil; Group IV - sodium valproate; Group V - Sinapis alba seed oil + ½ dose sodium valproate. Antioxidant markers and Brain-Derived Neurotrophic Factor (BDNF) levels were measured from the brain samples. The pathological changes were also determined using Cresyl violet staining. Sinapis alba oil did not prevent rats from developing status epilepticus but reduced the intensity and frequency of occurrence. Oil administration increased antioxidant levels and decreased lipid peroxide levels as well. The combination of oil and sodium valproate showed a synergistic effect in the status epilepticus model. The study results show that Sinapis alba can be used as an adjuvant in status epilepticus along with other antiepileptic drugs.

Essential oil of Lippia alba impedes the growth of Propionibacterium acnes by modulating membrane potential and ROS level

IntroductionPropionibacterium acnes (P. acnes) is a rod-shaped, anaerobic, Gram-positive, opportunistic bacterium, that causes infectious and inflammatory diseases, such as acne vulgaris synovitis-acnes-pustulosis-hyperostosis-osteitis syndrome, sarcoidosis, and prostate cancer. Earlier evidence suggests that essential oils have been used to treat skin diseases and disorders since ancient times. Thus, the present study investigated the anti-microbial activity of 28 essential oils from nine families, including Lamiaceae, Poaceae, Geraniaceae, Myrtaceae, Zingiberaceae, Verbenaceae, Cupressaceae, Asteraceae, and Cyperaceae against P. acnes. MethodsThe anti-bacterial susceptibility and efficacy of the essential oils were examined using paper disc diffusion, broth micro-dilution, time-kill kinetics and ROS assays. P. acnes was cultured under anaerobic conditions. The kinetic process evaluated the time and dose-dependent effects of essential oils. The alteration in membrane potential and ROS production were measured in terms of mean fluorescence intensity. Consequently, the chemical composition of essential oil was analyzed by GC and GC/MS analysis. ResultsEighteen essential oils inhibited the growth of P. acnes with a clear zone of 5 – 20.33 mm. Eucalyptus, Mentha, Palmarosa, Lemongrass, Citronella, Geranium, Patchouli, Ocimum, and Clarysage possess better antibacterial activity (ZGI: 10.33 ± 2.31 mm - 20.33 ± 4.72 mm). Lippia alba oil showed the minimum inhibitory concentration (MIC) of 0.125% v/v, and the MIC of Mentha, Ocimum, and Patchouli oils ranged from 0.25% to 0.50% v/v. Further, the concentration and time-kill kinetic study indicated that L. alba and O. sanctum oils suppress the growth at MIC till 12 h and at 2 × MIC until 72 h. Moreover, the oils induced ROS production with one fold change at 2 × MIC. In addition, O. sanctum oil altered the membrane integrity with a fold change of 1.0 and 2.0 at MIC and 2 × MIC, respectively, while L. alba oil modified a fold change of 1.0. Discussion/conclusionThe essential oils suppressed bacterial growth by inducing ROS and modulating membrane integrity. Therefore, L. alba and O. sanctum essential oils could be used as an alternative to chemicals/drugs for treating microbe-associated acne problems.

Antibacterial and anti-inflammatory activity of sesquiterpene lactones compounds extracted from Artemisia Herba Alba plan

The Artemisia Herba Alba plant, is widespread in Iraq and its municipal kind called Artemisia herba alba is used as anti-parasites and anti-bacterial agent, it also has effective against different kinds of infections, this activity returns to Sesquiterpene lactone compounds, which are the main product of the Artemisia Herba Alba oil. In this study, these compounds were extracted from the Artemisia Herba Alb plant. The effectiveness of five one-half concentrations (200,100,50,25,12.5) mg / ml, against five species of pathogenic bacterial isolates from urinary tract infections (UTI) cases were tested , The activity of Sesquiterpene lactone compounds was significant (P<0.05) for highest concentration of 200 mg /ml against P. aeruginosa, while the activity was not significantly against K .pneumoniae ,S. pneumoniae ,S. pyogenes when it is compared with standard antibiotic which is used against these pathogenic bacteria. In this study the anti-inflammatory activity of Sesquiterpene lactone compounds which induced by injection of carrageenan at the feet of laboratory mice, we found that these compounds was significantly (P <0.05) more active in reducing the inflammation caused by the injection of carrageenan but not those efficiency shown by the use of anti-inflammatory aspirin to reduce inflammation to the laboratory mice resulting from the injection of carrageenan.

Controlled release of Michelia alba oil vapour from plastic sachets to control the growth of Aspergillus flavus on brown rice and its possible mode of action

This study aimed to create antifungal volatile-releasing sachets, from various commercially available synthetics (Tyvek®; high density polyethylene; HDPE, polypropylene/polyethylene; PP/PE and polyamide/polyethylene; PA/PE) and bio-based plastic sachet materials (Polylactic acid; PLA and cellophane), containing Michelia alba (MA) essential oil to be used against A. flavus on malt extract agar (MEA) and brown rice. In addition, the bioactive compounds (total phenolic content and total flavonoid content) and antioxidant activity (DPPH, ABTS, and FRAP) of brown rice after treatment by the active sachets were examined. Results indicated that different sachet materials affected the release of the linalool and caryophyllene as antifungal volatiles. Tyvek® and PP/PE had a suitable permeability for controlling the release of the volatiles, which could be matched with the maximum concentration within 48 h, whereas PA/PE, PLA and cellophane had lower permeability. The antifungal volatiles released from Tyvek® and PP/PE sachets containing MA essential oil at 300 μl could completely inhibit the growth of A. flavus on MEA and brown rice for at least 20 days using accelerated conditions at 25 °C and 80%RH. No spore germination or deformed hyphae of A. flavus could be observed in the treated brown rice when compared to the control which showed swelling spores and regular structure with uniformity. In addition, the bioactive compounds and antioxidant activity of brown rice treated with MA essential oil in the Tyvek® and PP/PE sachets were higher than in the control. Therefore, this study demonstrates a good opportunity to implement antifungal volatile-releasing sachets containing MA for shelf-life extension and improving the antioxidant activity of brown rice.

The application and mechanism of action of Michelia alba oil vapour in GABA enhancement and microbial growth control of germinated brown rice

Germination of brown rice as a functional ingredient in various food products has been found to increase the γ-aminobutyric acid (GABA). Due to its high nutritional impact, germinated brown rice (GBR) grains are easily contaminated with bacteria, yeast/mould. Bacillus cereus is a foodborne pathogen and spoilage bacteria commonly found in GBR. This study was undertaken to use Michelia alba oil vapour (600, 1200 and 2400 μl L −1 ) to increase GABA during germination of brown rice grains over 48 h. The shelf life of the treated GBR was then determined during storage at 30 ± 2 °C for 28 days by finding physiochemical and physical changes in the treated rice and undertaking sensory evaluation. A mode of action was studied by using a scanning electron microscope (SEM) and gas chromatography-mass spectrometry (GC-MS). Results showed that the treated brown rice grains at 1200 μl L −1 before the germination process showed the highest GABA content in the shortest time at 18 h, reducing cooking time and having a softer texture compared to the control sample. The treated rice's aerobic plate count, yeast/mould count and B. cereus levels were better able to meet the microbiological criteria for rice and rice products (<5 log 10 cfu g −1 ) after 14 days of storage, when compared to the control, where the microbial growth exceeded the criteria within 7 days. Morphology of B. cereus was found to be destroyed due to the leaking of the cell wall after exposing the rice grain to M. alba . Trans -caryophyllene and β-elemene were the two main compounds of M. alba found in the treated rice, which are the key to destroying the cell wall and cell membrane of the bacteria. In addition, the GBR was found to be lighter in colour when exposed to a higher concentration of M. alba. These findings will help to improve GABA content during soaking in a short time period and make it safe to consume, thus developing the GBR industry. • M. alba oil enhanced γ-aminobutyric acid in brown rice grain during germination. • M. alba oil vapour inhibited bacteria, yeast/mould and B. cereus ~ two-fold. • M. alba oil offered higher L* value content in germinated brown rice (than control). • M. alba oil could reduce the hardness and the cooking time of GBR. • Caryophyllene and β-elemene were destroyed the structure of B. cereus .

Scents from the Brazilian Atlantic Forest Biome: chemical composition of essential oils from the leaves and flowers of seven species of Ipomoea (Convolvulaceae)

ABSTRACT Ipomoea alba, I. indica, I. amnicola, I. tiliacea, I. carnea, I. pes-caprae and I. batatas occur in fragments of the Atlantic Forest in the state of Pernambuco, Brazil. Essential oils from the leaves and flowers of these plants were analyzed using GC/FID and GC/MS. Ninety-one compounds were identified, accounting for more than 95% of the oils analyzed. Differences in the chemical profile were found among the Ipomoea oils. Greater chemical diversity was found in the leaf oils. β-Caryophyllene (leaves: 7.0 ± 0.6 to 42.1 ± 1.6%; flowers: 6.4 ± 0.8 to 36.5 ± 1.3%) was identified in abundance in all oils. cis-Cadina-1(6),4-diene was another sesquiterpene found in high percentages in the oils (11.8 ± 0.9 to 44.2 ± 1.7%), but was absent from the I. alba oils, in which the major constituent was germacrene D (leaves: 27.8 ± 1.0%; flowers: 45.8 ± 2.0%).

The effects of Michelia alba oil against mould on brown rice and assessing the brain response using electroencephalogram (EEG).

The objective of this study was to develop antifungal fragrant brown rice using the vapour phase of Michelia alba oil and to understand the effects of fragrant brown rice on consumer reactions using an electroencephalography (EEG) technique. The effect of M. alba oil vapour (300–900 µL/L) on the growth of moulds was studied in brown rice. Then, optimisation of the M. alba oil vapour (300–900 µL/L) was studied through sensory evaluation. Next, EEG was used to investigate the effect of fragrant cooked brown rice on human brain activity. In addition, the key components of M. alba oil on the sensory effects were determined. The results indicated that M. alba oil vapour ≥ 450 µL/L provided effective antifungal activity against natural moulds on brown rice for at least 90 days of storage at 25 °C at 100% RH. Furthermore, the optimal concentration of M. alba oil vapour for enhancing consumer preference and acceptance of cooked brown rice was 300–600 µL/L with a rejection threshold of 2,052 µL/L. Moreover, it was found that linalool was the main key component and caryophyllene and β-elemene were the minor components affecting the sensory quality enhancement. Interestingly, the EEG results showed that fragrant cooked brown rice could increase the power of alpha and beta waves in the human brain, indicating anti-stress effects and a relaxed mood. Therefore, M. alba oil vapour demonstrated good potential to enhance consumer acceptance and preference for cooked brown rice while controlling the significant growth of moulds in brown rice.

Treatment of fresh water hyacinth with essential oil emulsion and subsequent use of the plant material for control of Aspergillus flavus on rice dessert products

Essential oil emulsion, which is generally functionalized to have increased antifungal activity, has high solubility in water. The objective of this research was to develop an essential oil emulsion for absorption by water hyacinth plants in order to produce an essential oil absorbent material as a carrier of essential oil vapor that can be released to control mold in an enclosed packaging system. The fresh water hyacinth adsorbed the Michelia alba oil emulsion (100 µL/mL to 500 µL/mL) through its root system, transporting it to the stems and leaves after submerging the plant into the M. alba oil emulsion for 48 h. Dried sections (root, stem, and leaf) of the water hyacinth plant with absorbed M. alba essential oil emulsion released the M. alba vapor, inhibited Aspergillus flavus growth on malt extract agar (MEA), and also Thai dessert (Ja Mongkut) with the highest antifungal activity achieved with the concentration 500 µL/mL. The maximum essential oil absorption (345 µL/g) in the fresh plant was achieved after 48 h. The dried water hyacinth (≥ 0.4 g/L air) completely inhibited the growth of A. flavus for at least 7 days. In addition, the absorbent material prevented the growth of A. flavus on the Thai dessert (Ja Mongkut) with approximately 100% effectiveness (versus the control) for 10 days, thereby extending the shelf-life 2.5-fold in when compared with the control without essential oil.

The essential oil of Lippia alba Mill (Lamiales:Verbenaceae) as mosquitocidal and repellent agent against Culex quinquefasciatus Say (Diptera: Culicidae) and Aedes aegypti Linn (Diptera: Culicidae)

BackgroundBeing a low-risk insecticide, plant essential oils emerge as competent mosquitocidal and repellent candidates. However, essential oil may act differently in different mosquito species and different developmental stages of same mosquito species. In the current investigation, we evaluated the ovicidal, larvicidal, adulticidal and repellent activities of essential oil extracted from the leaves of Lippia alba against two medically important mosquito species, Aedes aegypti and Culex quinquefasciatus. The efficacy of the oil was assessed under laboratory conditions against different developmental stages of the selected species.ResultsFrom the findings, it can be inferred that L. alba oil is more effective as a repellent against both the targeted mosquito species. Results also demonstrated that ovicidal, larvicidal and repellent properties of the essential oil were higher against Culex quinquefasciatus than Aedes aegypti. GC-MS analysis of the oil showed the presence of aromadendrene oxide, caryophyllene oxide, etc. as major constituent compounds.ConclusionThe outcomes of this study clearly indicated that the essential oil of L. alba has the potentiality to act more effectively as a repellent, followed by a larvicidal agent against mosquito and at the same time the results revealed differential vulnerability of different mosquito species and their life stages against a particular plant essential oil.

Observation of a porbeagle shark Lamna nasus aggregation at a North Sea oil platform.

A minimum of 20 porbeagles Lamna nasus were observed circling the Alba oil platform (UK North Sea) over several days in July 2014. Although schools of fish often aggregate around oil platforms, less is known about their ability to aggregate pelagic sharks and L. nasus are rarely seen at the surface. This unusual observation provides new insights into L. nasus behaviour and habitat use and the potential role of offshore artificial structures on pelagic predators.

Short Communication: In vitro antibacterial activity of essential oils from twelve aromatic plants from East Kalimantan, Indonesia

Abstract. Kuspradini H, Putri AS, Egra S, Yanti. 2019. Short Communication: In vitro antibacterial activity of essential oils from twelve aromatic plants from East Kalimantan, Indonesia. Biodiversitas 20: 2039-2042. In the aim of this works was to investigate the antibacterial activity of twelve essential oils against Streptococcus mutans and Streptococcus sobrinus, oral pathogen causing dental caries. The essential oils were collected by a steam distillation method. Refractive index was measured by using a refractometer. The antibacterial activity of essential oils was determined using an agar well diffusion method. The yields of essential oils varied with the plant species. The steam distillation yielded clear to yellowish essential oils. Refractive indexes of oil were found to be in the range of 1.344 to 1.500. Syzigium sp. appeared to be more abundant in oil (1.54%) than the other plant species, while C. odorata was poorer (0.04%). All of the essential oils tested showed a varied level of inhibition zone (0-53.65 mm) against S. mutans and S. sobrinus. The oil from leaves of Cymbopogon citratus had the highest activity against S. sobrinus and S. mutans (53.15 and 52.85 mm, respectively). On the other hand, the Magnolia x alba oil showed the lowest activity against S. mutans and S. sobrinus (10.50 and 11.65 mm, respectively). The research results demonstrated that the essential oil in this study has the potency for development of dental health products for preventing and treating oral infections.

Antifungal activity of the essential oil obtained from Cryptocarya alba against infection in honey bees by Nosema ceranae.

The honeybee disease nosemosis type C is a serious problem since its causative agent, microsporidium Nosema ceranae, is widespread among adult honey bees. Some of the feasible alternative treatments that are used to control this disease are plant extracts. The aim of the present work was to evaluate the effects of essential oils of Chilean plant species, such as Cryptocarya alba, which is used against N. ceranae, and to identify and quantify the majority active compounds in the EO as well as their potential use for the control of nosemosis. Essential oils were obtained using the stripping steam technique with Clevenger equipment and were subsequently analyzed by Gas chromatography-mass spectrometry. Mortality was recorded daily over at least 8days as worker honeybees were exposed to a range of doses of EO dispersed in a sucrose solution. C. alba oil appears to be nontoxic to A. mellifera adults at the tested concentration (the same concentration inhibits the growth of N. ceranae), showing that this oil can be used for the treatment of nosemosis. EO effectiveness was demonstrated against N. ceranae by calculating the percentage of decrease in infected bees from untreated infected groups vs infected groups treated with EO or the reference drug fumagillin. It was determined that a dose of 4µg EO/bee was most effective in controlling N. ceranae development. We determined innocuous doses of C. alba essential oil for honeybees. We demonstrated the antifungal activity of C. alba EO at 4μg/bee against N. ceranae and compared it to its major monoterpenes, such as β-phellandrene (20μg/bee), eucalyptol (20μg/bee) and α-terpineol (20μg/bee). The major compounds of C. alba EO, α-terpineol, eucalyptol and β-phellandrene, had significant effects against Apis mellifera infection by N. ceranae, but the antifungal effect of the complete essential oil on N. ceranae was larger than the effect of α-terpineol, eucalyptol or β- phellandrene separately, showing that C. alba oil may be a candidate for the treatment or prevention of nosemosis.

Antifungal activity of Michelia alba oil in the vapor phase and the synergistic effect of major essential oil components against Aspergillus flavus on brown rice

The objectives of this study were to investigate the effect of essential oil (Michelia alba) vapor on the spore germination and mycelium growth of Aspergillus flavus on brown rice and to perceive the shelf life of the brown rice could be extended to a longer storage time. Different volumes (150, 300, 450 μl) of M. alba and a 300 μl linalool/caryophyllene combination at ratios of 10:1, 1:1, and 1:10 were first absorbed into plant absorbent material (Φ∼20 mm) before being put into a closed glass box (1L) containing A. flavus spore and the mycelium (Φ∼5 mm) in a Malt Extract Agar (uncovered plate). Mold testing was also carried out on brown rice with A. flavus spore suspension before being incubated at 25° C and 100% RH for 16 weeks. Quality tests e.g. texture, a sensorial evaluation (hedonic scale) of brown rice were also conducted. Results indicated that the vapor phase of M. alba at ≥ 300 μl L−1 air could inhibit both spore germination and A. flavus mycelium. Antifungal activity of M. alba in air was strongly correlated with the linalool/caryophyllene combination at the ratio of 10:1 in 300 μl L−1 air. In addition, M. alba vapor at 300 μl L−1 air was found to extend the shelf-life of the brown rice by four times (16 weeks) in comparison with the control treated without essential oil (4 weeks). After being cooked, the hardness of brown rice with volatile essential oil was found to be reduced by one third (compared to the control brown rice). The hedonic value (overall liking) of cooked brown rice packed with M. alba vapor at 300 μl for 1 week and then stored for 16 weeks was a 7, rated as “like moderately”. Therefore, this study has demonstrated the good potential of M. alba vapor to control mold growth on the surface of brown rice.

Evaluation of Sinapis alba as feedstock for biodiesel production in Mediterranean climate

Most of oilseed crops used in biodiesel (BD) production are also suitable for human consumption and widely consumed in the world. For this reason, some non-governmental organizations and social movements controversially pinpoint the making of BD as the main cause of increased global edible oils prices, especially in developing countries. In this way, non-edible oilseed crops are gaining prominence for BD synthesis. Particularly, in the Mediterranean climate there is a crop that may have potential as raw material for biodiesel production, namely white mustard (Sinapis alba). In the present study, this species has been grown during two consecutive years optimizing two factors, plant density and nitrogen fertilizer dose. The influence of these factors on biomass yield and fatty acid composition is studied. S. alba oil was chemically extracted with hexane providing a yield of 25% (mass of extracted oil per mass of grain seed, on dry basis). Physical properties and FA profile of S. alba oil (by gas chromatography) were analyzed. Results show that both plant density and nitrogen fertilizer dose have influence on concentration of both linoleic acid (C18:2) and linolenic acid (C18:3). In addition, the presence of erucic acid (C22:1) was significantly high (above 50%). Important BD properties included in standard EN 14214 were predicted by means of mathematical models. Results showed that white mustard oil BD may provide a cetane number above 60, a density value lower than 900kg/m3 and a cold filter plugging point suitable for it use in temperate climates, where this plant mainly grows. However, kinematic viscosity predicted value was above the maximum one allowed by European regulation (5mm2/s).

Chemical composition of Lippia spp. essential oil and antimicrobial activity against Aeromonas hydrophila

Phytotherapy can replace antibiotic administration as an alternative to control Aeromonas hydrophila, one of the main bacteria involved in the aetiology of farmed fish diseases. Given that plants of the Lippia spp. genus show biological potential for antimicrobial activity, this study evaluated the chemical composition of essential oils extracted from Lippia alba, Lippia origanoides and Lippia sidoides and their activity against A. hydrophila. The oils were obtained by steam distillation in a Clevenger-type apparatus and their composition determined by gas chromatography and mass spectrometry (CG/MS). Antibacterial activity was assessed by calculating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using broth microdilution method. The main compounds identified were geranial (25.4%) and neral (16.6%) in L. alba oil, carvacrol (40.4%) and p-cymene (11.4%) in L. origanoides oil and thymol (76.6%) and ortho-cymene (6.3%) in L. sidoides oil. The three Lippia species showed bacteriostatic and bactericidal action against A. hydrophila, with MICs and MBCs ranging from 1250 to 5000 μg mL−1. Of the species tested, the best performance was obtained with essential oil of L. sidoides.

Efficacy of Some Essential Oils Against Aspergillus flavus with Special Reference to Lippia alba Oil an Inhibitor of Fungal Proliferation and Aflatoxin B1 Production in Green Gram Seeds during Storage.

During mycofloral analysis of green gram (Vigna radiata (L.) R. Wilczek) seed samples taken from different grocery stores by agar and standard blotter paper methods, 5 fungal species were identified, of which Aspergillus flavus exhibited higher relative frequency (75.20% to 80.60%) and was found to produce aflatoxin B1 . On screening of 11 plant essential oils against this mycotoxigenic fungi, Lippia alba essential oil was found to be most effective and showed absolute inhibition of mycelia growth at 0.28 μL/mL. The oil of L. alba was fungistatic and fungicidal at 0.14 and 0.28 μL/mL, respectively. Oil had broad range of fungitoxicity at its MIC value and was absolutely inhibited the AFB1 production level at 2.0 μL/mL. Chemical analysis of this oil revealed geranial (36.9%) and neral (29.3%) as major components followed by myrcene (18.6%). Application of a dose of 80 μL/0.25 L air of Lippia oil in the storage system significantly inhibited the fungal proliferation and aflatoxin production without affecting the seed germination rate. By the virtue of fungicidal, antiaflatoxigenic nature and potent efficacy in storage food system, L. alba oil can be commercialized as botanical fungicide for the protection of green gram seeds during storage.