Evaluation of harvesting time and standardization of distillation duration for higher essential oil content and quality in German chamomile (Chamomilla recutita L.)

Essential oil yield and composition in aromatic crops might be affected by genetic, agronomical and environmental factors but till date there is no clear information about the harvesting time and distillation for higher essential oil content without affecting quality. The current study was carried out to evaluate harvesting of chamomile flowers without herb and with herb part at three different times (6 A.M., 12 P.M. and 6 P.M.) and four distillation treatments (3 h, 4 h, 5 h & 6 h) for dried chamomile flowers. Results indicated that essential oil content was more in chamomile flowers without herb (0.15-0.18%) as compared to flowers with herb (0.06-0.09%). Essential oil content in chamomile flowers without herb was found statistically at par at harvest time of 12 P.M. (0.18%) and 6 P.M. (0.18%) and significantly higher than harvesting time of 6 A.M. (0.15%). Essential oil of chamomile flowers without herb contained maximum α-bisabolol oxide-B, (Z)-spiroether, and chamazulene at 12 P.M. and 6 P.M. while, α-bisabolone oxide-A and α-bisabolol oxide-A were maximum at 6 A.M. and (E)-β-farnesene was more at 12 P.M. Similarly, in distillation experiment, higher oil content was observed in chamomile dried flowers which were hydro-distilled for 6 h (1.20%) compared to other hydro-distillation durations. Marker compounds i.e. α-bisabolol oxide-A, α-bisabolone oxide-A, α-bisabolol oxide-B, (E)-β-farnesene and chamazulene were more at 5 h and 6 h distillation duration while (Z)-spiroether was more at 3 h distillation duration. The present study showed that in order to obtain higher essential oil, flowers without herb harvested at 12 P.M or 6 P.M. should be subjected to 5-6 h hydro-distillation.

Anti-inflammatory, Antimicrobial and insecticidal properties of Daucus gracilis Steinh flowers essential oil.

Background:: Daucus gracilis Steinh belongs to the Apiaceae family. The flowers of this plant have been used by population of western Algeria for the treatment of mouth ulcers. However, very few studies exist of literature concerning the biological properties of Daucus gracilis Steinh flowers essential oil. Objectives:: The purpose of this work was to study the chemical composition of Daucus gracilis flowers essential oil and to evaluate their antimicrobial, insecticidal and anti-inflammatory properties. Methods:: The distilled essential oil was analyzed by GC and GC-MS. The antimicrobial activity of the essential oil was evaluated using two methods i) diffusion method, and ii) Micro dilution technique. The insecticidal activity of essential oil was evaluated against adults of Tribolium confusum by fumigant test. The in vitro assessment of anti-inflammatory property of essential oil was assessed by the protein denaturation method. Results:: Daucus gracilis flowers essential oil was mainly represented by Oxygenated monoterpenes such as Geranyl acetate (18.3%), Lavandulyl acetate (15.2%), Lavandulyl isobutyrate (13.6%) and Citronellyl isobutyrate (6.8%). According to the results of antimicrobial activity the essential oil of flowers presented prominent inhibitory action against Aspergillus flavus (0.06 μg/mL), followed by Staphylococcus aureus, Escherichia faecalis, Bacillus cereus and Candida albicans with MIC values of 0.125 μg/mL. The Daucus gracilis essential oil flowers proved to be very biocidal toward adults of Tribolium confusum, mortality of 100% of the population is noted with a dose of 2 μl/L air after 24 hours of exposure. Furthermore, the oil has shown has a very good inhibition of protein denaturation comparable to Diclofenac at concentration of 30 μL/mL. Conclusion:: Daucus gracilis essential oil can be used as pharmacological tools for inflammatory, antimicrobial and insecticidal properties.

Extraction and the Chemical Composition Analysis of the Essential Oil Flowers of Ficus hookeriana Corner

Objective: To analyse chemical constituents of the volatiles of Ficus hookeriana Corner. Method: The volatiles of bungei were extracted through steam distillation, and then the constituents were separated by GC and identified by MS. Result and Conclusion: 53 Compounds were identified. The principal chemical constituents of the volatiles of Ficus hookeriana Corner are Acetal (6.323%)、Benzyl Alcohol（11.781%）、Benzoic acid, methyl ester（1.749%）、Linalol（4.920%）、Phenylethyl Alcohol（3.101%）、Acetic acid phenylmethyl ester（1.415%）、Elemicin（5.099%）、Morillol（2.441%）、 Griseoxanthone C（1.212%）、Prednisolone（3.302%）、Fenolipuna（2.672%）、Norpluviine（1.494%）、Crotonosine（28.115%）、Griseoxanthone C*（2.085%）、α-Endosulfan（1.055%）、1,4-diamino-2-methoxy-9,10-Anthracenedione（3.349%）and so on.

Reproductive biology of Monttea aphylla (Scrophulariaceae)

Monttea aphylla is an aphyllus shrub abundant in the Monte Desert, Argentina. This species presents particular floral syndromes including violet, tubular flowers with trichome elaiophores that produce oil. Oil flowers are associated with specialised bees with an oil-collecting apparatus. To better understand the reproductive biology of M. aphylla, the mating system, flowering phenology, the associated pollinator assemblage and foraging behaviour was determined at the southern-most part of its distributional range. Results were compared with those of previous studies and discussed. At this southern location M. aphylla is a self-incompatible species; it relies on pollinators for fruit production and presented a low fruit set. Flowering occurred during the spring, from October to December. M. aphylla was pollinated by three species of bees (Apidae); two generalist species (Centris brethesi and Mesonychium jenseni) and one specialist to M. aphylla (Centris vardyorum). M. jenseni is a cleptoparasite of Centris species. Centris species are oil-collecting bees and showed territorial behaviour (i.e. they always visited a restricted group of plants which they protected from other visitors), they visited several flowers/plants, which enhanced geitonogamous self-pollination and reduced pollination efficiency, and which might explain the low natural fruit set observed in M. aphylla. C. vardyorum was the most important pollinator of M. aphylla in the study area. The reproductive biology of M. aphylla differs along its distributional range. Apparently, southern populations of M. aphylla are more specialised than the northern populations, the former being pollinated by a few related pollinator species whereas at the northern location a variety of visitors were observed.

The evolution and loss of oil-offering flowers: new insights from dated phylogenies for angiosperms and bees

The interactions between bees that depend on floral oil for their larvae and flowers that offer oil involve an intricate mix of obligate and facultative mutualisms. Using recent phylogenies, new data on oil-offering Cucurbitaceae, and molecular-dating, we ask when and how often oil-offering flowers and oil-foraging bees evolved, and how frequently these traits were lost in the cause of evolution. Local phylogenies and an angiosperm-wide tree show that oil flowers evolved at least 28 times and that floral oil was lost at least 36–40 times. The oldest oil flower systems evolved shortly after the K/T boundary independently in American Malpighiaceae, tropical African Cucurbitaceae and Laurasian Lysimachia (Myrsinaceae); the ages of the South African oil flower/oil bee systems are less clear. Youngest oil flower clades include Calceolaria (Calceolariaceae), Iridaceae, Krameria (Krameriaceae) and numerous Orchidaceae, many just a few million years old. In bees, oil foraging evolved minimally seven times and dates back to at least 56 Ma ( Ctenoplectra ) and 53 Ma ( Macropis ). The co-occurrence of older and younger oil-offering clades in three of the four geographical regions (but not the Holarctic) implies that oil-foraging bees acquired additional oil hosts over evolutionary time. Such niche-broadening probably started with exploratory visits to flowers resembling oil hosts in scent or colour, as suggested by several cases of Muellerian or Batesian mimicry involving oil flowers.