The profile and bioactivity of essential oil (EO) depends on genetic, environmental, and other factors. We hypothesized that the basil EO may be influenced by the distillation methods. Hence, a study was conducted to evaluate the effect of steam distillation (SD) and hydrodistillation (HD) extraction method on the yield, composition, and bioactivity of EO of sweet basil (Ocimum basilicum) and holy basil (Ocimum tenuiflorum). In both basil species, the EO yield (content) was significantly higher from SD than from HD. There were significant differences in the compounds' concentrations of EO obtained from SD and HD as well, however, the same compounds were identified in the EO from HD and SD. In the EO of O. basilicum, the concentration of 74% of the identified compounds were higher in SD than HD, whereas in the EO of O. tenuiflorum, the concentration of 84% of identified compounds were higher in SD than in HD. However, the concentrations of two of the major compounds of O. basilicum EO (estragole and methyl cinnamate) and a major compound of O. tenuiflorum EO (methyl eugenol) were significantly higher in HD than in SD. The type of distillation did not affect the antioxidant capacity of basil EO within the species. This study demonstrated that the type of distillation may significantly affect oil yield and composition but not the antioxidant capacity of the EO from sweet and holy basil.

Interest in capturing and reusing runoff from irrigation and rainfall in container nurseries is increasing due to water scarcity and water use regulations. However, grower concerns related to contaminants in runoff water and other issues related to water safety are potential barriers to the adoption of water capture and reuse technologies. In this review, we discuss some of the key concerns associated with potential phytotoxicity from irrigating container nursery crops with recycled runoff. The concentration of pesticides in runoff water and retention ponds is orders of magnitude lower than that of typical crop application rates; therefore, the risk of pesticide phytotoxicity from irrigation with runoff water is relatively low. Nonetheless, some pesticides, particularly certain herbicides and insecticides, can potentially affect crops due to prolonged chronic exposure. Pesticides with high solubility, low organic adsorption coefficients, and long persistence have the greatest potential for crop impact because they are the most likely to be transported with runoff from container pads. The potential impact on plant growth or disruption of physiological processes differs among pesticides and sensitivity of individual crop plants. Growers can reduce risks associated with residual pesticides in recycled irrigation water by adopting best management practices (e.g., managing irrigation to reduce pesticide runoff, reducing pots spacing during pesticide application, use of vegetative filter strips) that reduce the contaminant load reaching containment basins as well as adopting remediation strategies that can reduce pesticide concentrations in recycled water.

Pumping water from coal seams decreases the pressure in the seam and in turn releases trapped methane; this is the most common and economic method of methane extraction. The water that is pumped out is known as "coal-bed methane water" (CBMW), which is high in sodium and other salts. In the past 25 yr, the United States has seen a 16-fold increase in the production of coal bed methane gas, and trillions of cubic meters are yet to be extracted. There is no sustainable disposal method for CBMW, and there are very few studies investigating the effects of this water on plants and their secondary metabolites and on soil properties. This study was conducted to determine the effects of CBMW on soil chemical properties and on the biomass and essential oil yield and composition of dill (Anethum graveolens L.). This crop was grown in a greenhouse and was subjected to different levels of CBMW treatment: tap water only; 25% CBMW, 75% tap water; 50% CBMW, 50% tap water; 75% CBMW, 25% tap water; and 100% CBMW. The major dill oil constituents, limonene and a-phellandrene, were not affected by the treatments; however, the concentration of dill ether increased with increasing CBMW levels, whereas the concentration of carvone decreased. In soil, sodium level significantly increased with increasing level of treatment, but pH and cation exchange capacity were not much affected. Coal bed methane water could be used for irrigation of dill for one growing season, but longer-term studies may be needed to clarify the long-term effects on soil and plant. Coal-Bed Methane Water Effects on Dill and Its Essential OilsShital Poudyal, Valtcho D. Zheljazkov,* Charles L. Cantrell, and Thijs Kelleners M ethane is a natural gas that is mainly extracted from coal seams. Pumping water out of coal seams decreases pressure, which in turn releases trapped methane gas from the seam along with the water being pumped out (Mary and Gurney, 2001). This water, also called "coproduced water" or "coal-bed methane water" (CBMW), contains high amounts of sodium, bicarbonate, and other salts and is considered waste water by the USEPA; therefore, it is considered to be unsuitable for agricultural purposes (Stearns et al., 2005;Huang and Natrajan, 2006). In the United States, production of coal-bed methane gas rose from 2.57 billion m 3 in 1989 to 41.529 billion m 3 in 2013. The probability for greater production of methane and the associated greater discharge of CBMW exists because the United States still holds 1.5 trillion m 3 of unreleased methane gas. An average coal-bed methane well discharges about 45 L CBMW min −1 (Young, 2005; Energy Information Administration, 2015), and usually there are many wells operating at a single site. Coal-bed methane water is generally disposed of by evaporation ponds or by direct discharge into streams, both of which are unsustainable. Coal-bed methane water degrades soil structure, depletes microorganisms and their action in soil, reduces vegetation density, and pollutes ground water. Apart from these detrimental effe...

Japanese cornmint, also known as menthol mint (Mentha canadensis L. syn M. arvensis L.), is an essential oil crop cultivated in several countries in Asia and South America. The plant is currently the only commercially viable source for natural menthol as a result of the high concentration of menthol in the oil compared with other crops. The hypothesis of this study was that harvesting at regular intervals within a 24-hour period would have an effect on essential oil concentration and composition of Japanese cornmint grown at high altitude in northern Wyoming. Flowering plants were harvested every 2 hours on 7 to 8 Aug. and on 14 to 15 Aug. and the essential oil was extracted by steam distillation and analyzed by gas chromatography–mass spectroscopy (GC-MS). The effects of harvest date (Harvest 1 and Harvest 2) and harvest time (12 times within a 24-hour period) were significant on oil concentration and yield of menthol, but only harvest date was significant on the concentration of menthol in the oil. The interaction effect of harvest date and harvest time was significant on water content and on the concentrations of menthol and menthofuran in the oil and on the yield of limonene, menthol, and menthofuran. Overall, the oil concentration in grams per 100 g dried material for the two harvests (1.26 and 1.45, respectively), the concentration of menthol in the oil (67.2% and 72.9%, respectively), and menthol yield (1066 to 849 mg/100 g dried biomass) were higher in plants at Harvest 2 as compared with plants at Harvest 1. The oil concentration was higher in plants harvested at 1100 hr or at 1300 hr and lowest in the plants harvested at 1500 hr. Menthol yield was the highest in plants harvested at 1300 hr and lowest in the plants harvested at 0700 hr, 1900 hr, or at 0300 hr. This study demonstrated that harvesting time within a 24-hour period and harvest date (maturity of the crop) may affect essential oil concentration and composition of Japanese cornmint grown at high altitude in northern Wyoming.