Determination of volatile aroma compounds of Antrodia juniperina

Antrodia juniperina is one of the most common Antrodia genus species in Turkey, which is regarded as a medicinal plant in some countries. The aim of this study is to determine the volatile aroma compounds (compounds) of A. juniperina. The volatile aroma compounds of A. juniperina were analyzed by headspace gas chromatography (GC-MS). 22 volatile compounds such as alcohols, aldehyde, acids, ketones, terpenes, ester, 11,13-dihydroxy-11.β.H-arbusculin benzofuran, 2H-1benzopyran, 6-α-cadina-4,9-diene, and diethyl phthalate were determined. Nerolidol (alcohol), 11,13dihydroxy-11.β.H-arbusculin benzofuran, 3-methoxy-5-methyl-benzaldehyde (aldehyde), 3-octanone (ketone), 3,7-dimethyl-1,6-octadien-3-ol (alcohol), and 3-octanol (alcohol) were identified as major aroma components in A. juniperina with 76.22%.

Antrodia genus consists approximately of 50 species and some of these species are known as medicine in some countries (Anonymous 2012).Aroma compounds of Taiwanofungus camphoratus (Syn: Antrodia camphorate) known as herbal medicine in Taiwan (Liu et al., 2008) were studied by many researchers.78 aroma compounds were determined in T. camphoratus and 39 of them were terpenoids (Geethangili and Tzeng, 2011).In addition to benzenoids, lignans, benzoquinones, maleic/succinic acid, sterols, nucleotides, and fatty acids were found.Also, anti-cancer activities, antiinflammatory/immunomodulatory effects, anti-hepatitis B virus replication, anti-oxidant activities, hepatoprotective activity, neuprotective effect, antihypertensive effect, vasorelaxation effect, prevention of liver fibrosis of this mushroom have been reported (Geethangili and Tzeng, 2011).The usage of natural aroma components of T. camphoratus in food and cosmetic industry has been noted by Liu et al. (2008), and 42 organic components (esters, alcohols, acids, ketones) were identified by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O).In a study conducted by Wu et al. (2007), antioxidant activities  T. camphoratus were studied, and the polysaccharides, sesquiterpene lactones, steroids, and triterpenoids contained in this mushroom as well as its anti-cholinergic, anti-serotonin, anti-inflammatory, antioxidant, anti-cancer, and anti-hepatitis B virus activities were reported in the study.
A. juniperina is a common mushroom in Turkey.Distribution of this mushroom in Turkey was studied by Dogan et al. (2011).It has very distinct and palatable smell when it is fresh.However, there has not been a detailed study on volatile aroma compounds of A. juniperina to date.Therefore, volatile aroma components of A. juniperina collected from nature were determined by GC in this study.
The collected (approximately 250 g) samples of A. juniperina were immediately crushed in a mortar and were homogenated.The samples were harvested in a commercial ripen stage and were immediately homogenized using fruit blender.Triplicate volatile compounds were analyzed on an automatic HS-40 head space autosampler Perkin Elmer Turbo Mass Clarus 600 GC/MS.Automatic Headspace Technique (Purge/Trap) was used for extraction of volatile compounds in collected A. juniperina samples.Samples (5 g) were weighed and immediately transferred into the autosampler Headspace vials (20 ml) adding 1 ml of NaCl (2%) and samples were held in place for 20 min at 35°C.Thermal desorption was performed in the injector glass liner at 250°C for 2 min.The GC-MS system used for analysis was Perkin Elmer Turbo Mass Clarus 600 GC/MS operating at 70 eV in electron ionization (EI) mode.Data acquisition and analysis were performed by using Enhanced Data Analysis software, supplied by the manufacturer.Substances were separated on a fused silica capillary column, HP-5MS flexible 1 glass capillary gas chromatography column (60 m, 0.25 mm, 0.25 μm, Agilent Technologies Co., Ltd., Palo Alto, USA).The GC oven temperatures in this system was kept at 60°C for 10 min and was programmed to 220°C at a rate of 4°C min -1 , and then it was kept constant at 220°C for 10 min, then it was programmed to 260°C at a rate of 1°C min -1 with splitless.The injector temperature was set at 250°C.MS was taken at 70 eV.The mass range was m/z 35 to 425.A library search was carried out using Wiley, Nist, and Flavor GC-MS Libraries.MSs were also compared with those of reference compounds and was confirmed with the aid of retention indices from published sources.Relative percentage amounts of the separated compounds were calculated from total ion chromatograms through a computerized integrator.

Conclusion
A. juniperina is a common mushroom in Turkey and it has very distinctive and pleasant smell when it is fresh.Some Antrodia species are known as herbal medicine in some countries.Therefore, volatile aroma compounds of A. juniperina were determined in this study.Total of 22 aroma components were identified (alcohols, terpenes, acids, aldehyde, ketones, ester).Alcohols (especially Nerolidol) were the major aroma compound with 52.37% of the total aroma.Ketones were found as important aroma components with 7.05%.11,13-dihydroxy-11.β.Harbusculin benzofuran was identified as the second major aroma component with 11.84%.This component was followed with 3-methoxy-5-methyl-benzaldehyde (10.45%).Results of this study showed that A. juniperina is rich in terms of aroma.Doğan et al. 3255

Figure 1 .
Figure 1. A. juniperina used in this study. of

Table 1 .
Volatile composition of A. juniperina by HS/GC-MS.