Chemical mimicry in the corpse flower: Floral odor and phytochemical profiles of Amorphophallus titanum (Becc.) Becc.

Authors: RAMAN, VIJAYASANKAR - University Of Mississippi; Wang, Mei; AVULA, BHARATHI - University Of Mississippi; LEE, JOSEPH - University Of Mississippi; MANFRON, JANE - State University Of Ponta Grossa; KHAN, IKHLAS - University Of Mississippi

Submitted to: Biochemical Systematics and Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/16/2024
Publication Date: 11/20/2024
Citation: Raman, V., Wang, M., Avula, B., Khan, I. 2024. Floral scent analysis and phytochemical profiling of titan arum (Amorphophallus titanum) by headspace-solid phase microextraction gas chromatography/liquid chromatography coupled with quadrupole-time of flight mass spectromet. Biochemical Systematics and Ecology. 118:1-12. https://doi.org/10.1016/j.bse.2024.104.
DOI: https://doi.org/10.1016/j.bse.2024.104920

Interpretive Summary: Amorphophallus titanum (Becc.) Becc., the titan arum, is popularly known for having the world's largest unbranched inflorescence. It is also commonly known as the "corpse flower" due to its characteristic unpleasant odor emitted during peak blooming. This plant is a rare, endemic and endangered species, legally protected in Indonesia and occasionally cultivated in botanical gardens. The present study aimed to investigate phytochemical profiles of the floral and vegetative parts of the titan arum plant. 54 volatile compounds were identified by SPME GC/MS in the bloom representing 68-94.7% of the volatile composition. 38 non-volatile compounds, including flavonoids, anthocyanins, amino acids, xanthone, C-glycosylflavones and organic acids, were found in different parts of the plant using LC/Q-ToF. The comprehensive studies involving the volatile and non-volatile, polar compounds in present work add to the existing knowledge and illustrate the wide spectrum of chemical composition of titan arum flora scent. It has concluded that the quality and quantity of the scent's volatile composition may vary between flowers, places, and different times of flowering. These studies also throw more on the behavior of titan arum flowering and the biology of its pollination.

Technical Abstract: Titan arum, or the corpse flower (Amorphophallus titanum), is well known for its world's largest inflorescence and characteristic odor. This paper provides detailed profiling of volatile constituents of titan arum bloom and non-volatile components of the plant's various floral and vegetative parts. The floral odor samples were collected at different times of the bloom using HS-SPME fibers, and the samples were analyzed by GC/Q-ToF. The phytochemical constituents of various parts of the plant, including the leaves, petioles, tubers and different parts of the inflorescence such as bract, spadix and male and female flowers, were analyzed by LC/Q-ToF. Fifty-four volatile compounds were identified in the bloom representing 68-94.7% of the volatile composition. Major volatiles of the bloom included toluene, di-t-butyl-4-butylphenol, ethylene glycol-adipate-diethylene glycol and diethyl phthalate. A total of 38 non-volatile compounds, including flavonoids, anthocyanins, amino acids, xanthone, C-glycosylflavones and organic acids, were found in different parts of the plant. The most predominant constituents of anthocyanins were cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside. On the other hand, C-glycosylflavones (vitexin, orientin, shaftoside and their glycosides) and flavonols (quercetin, kaempferol and isorhamnetin glycosides) were identified from various parts of the plant. Amino acids, such as phenylalanine, tryptophan, leucine, isoleucine, valine, tyrosine and methionine, were also detected in all analyzed parts, with leucine and isoleucine being the most predominant ones.