Introduction -Sweet Woodruff Gallium odoratum
Sweet Woodruff has gained significant recognition in the field of medicinal applications. The primary objectives of this research project are to conduct an analysis of sweet woodruff hydrosols which were obtained using microwave techniques and subsequently examined through gas chromatography-mass spectroscopy (GC-MS).
Sweet Woodruff, Gallium odoratum
Sweet Woodruff, Gallium odoratum

Sweet Woodruff, Gallium odoratum

Gallium odoratum, often referred to as sweet woodruff,is a fascinating plant with a wonderful scent and numerous useful applications. It is a member of the Rubiaceous family and is commonly grown for its exquisite blossoms in Belgium's forested areas. This plant is well-known around the world for its aesthetic qualities, health advantages, and culinary diversity. It also releases a lovely perfume resembling freshly cut hay[1].

[1] Martin, B., and M. Bodson. "Investigation on the morphological and chemical variability of sweet woodruff (Galium odoratum (L.) Scop.) in Southern Belgium." IV International Symposium on Breeding Research on Medicinal and Aromatic Plants-ISBMAP2009 860. 2009.

Sweet Woodruff, Gallium odoratum
Sweet Woodruff, Gallium odoratum

Sweet woodruff hydrosols were prepared using the microwave extraction method which enhanced extraction efficiency and preservation of delicate volatile compounds that may be lost during traditional distillation methods [4]. 200g of dried sweet woodruff were soaked with around 500mL of boiling hot distilled water in the microwave extraction vessel. Following an overnight soaking period, the infused herbaceous material was ready for extraction. To capture the resulting hydrosol droplets, a 300mL beaker was positioned and screwed at the center of the microwave extraction vessel. An ice cone, designed to facilitate optimal condensation, was positioned atop the vessel's lid. The microwave then runs for a duration of 9 minutes. Upon completion of each 9-minute cycle, the extraction vessels were removed from the microwave. The resulting hydrosols collected in the 200mL beaker were then transferred to a clean, dry glass bottle. A new ice cone was then placed and secured on the lid. The extraction process was repeated twice more, with each cycle lasting 9 minutes, to ensure the comprehensive extraction of all volatile and water-soluble components from the Sweet Woodruff.

[4] Nazlić, Marija, et al. "Extraction, Composition and Comparisons–Free Volatile Compounds from Hydrosols of Nine Veronica Taxa." Horticulturae 9.1 (2023): 16.

Sweet woodruff under microwave extraction
Sweet woodruff under microwave extraction

Sweet woodruff hydrosols were then evaluated using a DB-5 MS column and GC-MS. To eliminate water,which is too polar for the GC column, 5mL of the hydrosols sample was filtered by solid phase extraction (SPE) prior to the analysis leveraging the GC-MS equipment. During the first test run, which employed 5 mL of sweet woodruff hydrosols, revealed that practically all the components—aside from coumarin. To generate a calibration curve, an internal standard was added at a range of concentrations between 1 mg/ml and 0.025 mg/ml. 10 mL of sweet woodruff hydrosols was filter and used instead of 5 mL to ensure that the concentrations fell inside the calibration curve range. As shown in Figure 1, the linear regression trendline with equation of y=6E+07x –404851 and R squared value of 0.9946 was agreed upon and used to evaluate all the chemical components discovered in sweet woodruff.

Standard calibration curve of sweet woodruff
Figure 1: Standard calibration curve of 4-ethylguaiacol

The utilization of GC-MS analysis to examine Sweet Woodruff hydrosols offers significant insights into their chemical makeup, facilitating the detection and characterization of volatile compounds within the hydrosols. The chromatogram’s peaks were all recognized by comparing obtained mass spectra, estimated RI values with established reference databases [11], was listed in Table1. It was then found that this herbaceous plant boasts an extensive repertoire of bioactive compounds, including coumarins, furan, terpineol, and L-carvone, known for their antioxidant and anti-inflammatory properties. [6].

[6] Mandal, Debopriya, Tanmay Sarkar, and Runu Chakraborty. "Critical review on nutritional, bioactive, and medicinal potential of spices and herbs and their application in food fortification and nanotechnology."Applied Biochemistry and Biotechnology195.2 (2023): 1319-1513.

[11]NIST Chemistry Webbook, SRD 69. Chemical Name Search. (n.d.).https://webbook.nist.gov/chemistry/name-ser/

Figure 2: Chromatogram of sweet woodruff hydrosols
Figure 2: Chromatogram of sweet woodruff hydrosols

Sweet Woodruff has several therapeutic effects resulting from the presence of coumarin, furan, terpineol, and L-carvone, which have been harnessed to alleviate nerve pain, treat skin diseases, alleviate chest congestion, promote diuresis to relieve water retention, accelerate wound healing, muscle relaxant and address various other ailments [2][7]. Wine, tea, and punch are some of the alcoholic beverages that are frequently flavoured with Sweet Woodruff leaves. Its distinct flavour also improves the flavour of both sweet and savoury foods [3]. Furthermore, Sweet Woodruff may possess mild diuretic and antispasmodic properties, augmenting its therapeutic effectiveness[5]. The utilization of this analytical technique provides a comprehensive comprehension of the hydrosols' aromatic profile and potential bioactive constituents, thereby enhancing our understanding of their therapeutic potential.

[2] DerSarkissian, C. (Ed.). (2021, June 11). Sweet Woodruff: Health benefits, side effects, uses, Dose & precautions. RxList, https://www.rxlist.com/sweet_woodruff/supplements.htm

[3]Lim, T. K. "Galium odoratum."Edible Medicinal and Non-Medicinal Plants: Volume 8, Flowers. Dordrecht: Springer Netherlands, 2014. 700-704.

[5] Kahkeshani, Niloofar, et al. "Antioxidant and burn healing potential of Galium odoratumextracts."Research in pharmaceutical sciences8.3 (2013): 197

Composition of sweet woodruff hydrosols
Table 1: Compound found in Sweet woodruff hydrosols using GC-MS.

Bioactive compounds of coumarin, furan, terpineol, and L-carvone were known for their antioxidant and anti-inflammatory properties which found in sweet woodruff hydrosols.

[7] Banerjee, Rumpa, H. K. S. Kumar, and Mrityunjay Banerjee. "Medicinal significance of furan derivatives: a review."International Journal of Research in Phytochemistry and Pharmacology5.3 (2015): 48-57.

[8] Pereira, Thiago M., et al. "Coumarin compounds in medicinal chemistry: some important examples from the last years." Current Topics in medicinal chemistry 18.2 (2018): 124-148

[9] Bouyahya, Abdelhakim, et al. "Health benefits and pharmacological properties of carvone." Biomolecules 11.12 (2021): 1803.

[10] Khaleel, Christina, Nurhayat Tabanca, and Gerhard Buchbauer. "α-Terpineol, a natural monoterpene: A review of its biological properties." Open Chemistry 16.1 (2018): 349-361.

Bioactive compounds found within hydrosols
Figure 3: Bioactive compounds with antioxidant and anti-inflammatory properties found within hydrosols.

My name is Rachael Lee, an international student from Malaysia currently in my fourth year of pursuing an Honours bachelor’s degree in chemistry at the University of Ottawa. Having the opportunity to volunteer at John L. Holmes Mass Spectrometry Facility not only allows me to develop my practical skills in analytical chemistry but also provides an invaluable platform for me to learn more about mass spectrometry and analytical chemistry. Moreover, with the aid of gas chromatography-mass spectrometry which allows examination of the chemicals contained in the hydrosols of various raw materials, I am thrilled to pursue analyzing additional plant samples using the methods I have acquired from this experience.

Rachael Lee
Rachael Lee