Susan Kunnas

Dr. Susan Kunnas


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 November 2021 in Molecules
Verified
Journal Article
Open access
PDF file
RKRisto Korpinen
Risto Korpinen
AVAnna-Liisa Välimaa
Anna-Liisa Välimaa
JLJaana Liimatainen
Jaana Liimatainen
SKSusan Kunnas
Susan Kunnas
Traditionally, arctic Finnish Angelica (Angelica archangelica L.), marsh Labrador tea (Rhododendron tomentosum, syn. Ledum palustre) and common tansy (Tanacetum vulgare) have been used as medicinal herbs in folklore medicine. However, these underutilised plants are a source of, e.g., oil-based compounds, which could benefit many modern applications implemented by the green chemistry extraction methods, as well. We extracted Angelica, marsh Labrador tea and common tansy by non-toxic and recyclable extraction methods, i.e., hydrodistillation and supercritical carbon dioxide (scCO2) extraction; characterised the essential oils (EOs) and scCO2 extracts by combination of gas chromatography and mass spectrometry (GC-MS), and in addition, analysed the antimicrobial properties. As expected for Angelica root and common tansy inflorescence, the scCO2 extraction method produced less amount of volatile compounds compared to hydrodistillation. On the other hand, more coumarins, alkanes, fatty alcohols and fatty acids were obtained. Additionally, sesquiterpenoids palustrol and ledol were predominant compounds in both marsh Labrador tea EO and scCO2 extract. According to our results, however, all the EOs and scCO2 extracts showed broad spectrum of antimicrobial activities against the selected microbes, but the effects were extract-specific. The strongest and broadest antimicrobial activities were performed by marsh Labrador tea scCO2 extract, which showed extremely strong effect on Staphylococcusaureus subsp. aureus and strong effect on Candida albicans.

12 September 2020 in Molecules
Verified
Journal Article
Open access
PDF file
TJTuula Jyske
Tuula Jyske
EJEila P. Järvenpää
Eila P. Järvenpää
SKSusan Kunnas
Susan Kunnas
TSTytti Sarjala
Tytti Sarjala
JRJan-Erik Raitanen
Jan-Erik Raitanen
TTTuomo Tupasela
Tuomo Tupasela
Developing shoots, i.e., sprouts, and older needles of Norway spruce (Picea abies (L.) Karst.) have traditionally been used for medicinal purposes due to the high content of vitamins and antioxidants. Currently, sprouts are available as, for example, superfood and supplements. However, end-product quality and nutritive value may decline in the value-chain from raw material sourcing to processing and storage. We studied (1) impacts of different drying and extraction methods on nutritional composition and antioxidative properties of sprouts and needles, (2) differences between sprouts and needles in nutritional composition and microbiological quality, and (3) production scale quality of the sprouts. Additionally, (4) sprout powder was applied in products (ice-cream and sorbet) and consumer acceptance was evaluated. According to our results, older needles have higher content of dry matter, energy, and calcium, but lower microbial quality than sprouts. Sprouts showed a higher concentration of vitamin C, magnesium, potassium, and phosphorus than older needles. Freeze-drying was the best drying method preserving the quality of both sprouts and needles, e.g., vitamin C content. The antioxidative activity of the sprout extracts were lower than that of needles. Ethanol-water extraction resulted in a higher content of active compounds in the extract than water extraction. Sensory evaluation of food products revealed that on average, 76% of consumers considered sprout-containing products very good or good, and a creamy product was preferred over a water-based sorbet.

25 April 2024 in Textile Research Journal
Verified
Journal Article
Closed access
SKSusan Kunnas
Susan Kunnas
JTJenni Tienaho
Jenni Tienaho
THThomas Holmbom
Thomas Holmbom
SSSuvi Sutela
Suvi Sutela
JLJaana Liimatainen
Jaana Liimatainen
RKRisto Korpinen
Risto Korpinen
In this study antimicrobial linen-cotton jacquard textiles were manufactured using green chemistry methods. The functionalization of the fabrics was executed by impregnating chitosan microencapsulated bio-based oils from angelica ( Angelica archangelica L.) (AAC) and marsh Labrador tea ( Rhododendron tomentosum Harmaja) (MLTC) obtained with pilot scale supercritical carbon dioxide extraction. The chemical compositions of the extracts of angelica and marsh Labrador tea were analyzed by a combination of gas chromatography and mass spectrometry. The antimicrobial activities of the extracts, AAC and MLTC microcapsules, and the microencapsulated textiles (AAC and MLTC textiles) were analyzed against gram-positive Staphylococcus aureus and gram-negative Escherichia coli bacteria, dimorphic yeast Candida albicans and filamentous mold Aspergillus brasiliensis. The AAC textile proved 40% inhibition against S. aureus, whereas the MLTC textile demonstrated 43.8% and 51.7% inhibition against both S. aureus and E. coli, respectively. Although the chitosan shell material itself indicated mild activity against both bacterial strains, the extracts increased the antibacterial activities in microencapsulated textiles. In addition, the antifungal impact of the MLTC textile was demonstrated against A. brasiliensis. According to the Fourier transform infrared spectroscopy with attenuated total reflection and field emission scanning electron microscopy analyses, covalent bonding between the microcapsules and textile fibers was established with citric acid as a cross-linker. The antimicrobial activity was also shown to persist in the MLTC textiles after six domestic washing cycles.

22 March 2026 in Materials & Design
Verified
Journal Article
Open access
SKSusan Kunnas
Susan Kunnas
JTJenni Tienaho
Jenni Tienaho
Petri KilpeläinenPetri Kilpeläinen
Petri Kilpeläinen
MHMarjo Haapakoski
Marjo Haapakoski
APAnni Perämäki
Anni Perämäki
TJTuula Jyske
Tuula Jyske

20 November 2019
Verified
Conference Paper
Open access
PDF file
SKSusan Kunnas
Susan Kunnas
RKR. Korpinen
R. Korpinen
JPJ.-M. Pihlava
J.-M. Pihlava
AVA.-L. Välimaa
A.-L. Välimaa
MLM. Laurila
M. Laurila
HPH. Pietarinen
H. Pietarinen