Determination of the Allelopathic Potential of Cambodia’s Medicinal Plants Using the Dish Pack Method

Abstract

Plants produce several chemically diverse bioactive substances that may influence the growth and development of other organisms when released into the environment in a phenomenon called allelopathy. Several of these allelopathic species also have reported medicinal properties. In this study, the potential allelopathic effects of more than a hundred medicinal plants from Cambodia were tested using the dish pack method. The dish pack bioassay method specifically targets volatile allelochemicals. Twenty-five species were found to have significant inhibitory effects on lettuce radicle growth. Eleven different plant families, including Iridaceae (2), Apocynaceae (2), Poaceae (2), Sapindaceae, Araceae, Combretaceae, Orchidaceae, Clusiaceae, Zingiberaceae, Rutaceae and Asparagaceae had the plant species with high inhibitory effects. Allophyllus serrulatus had the highest growth inhibitory effect on lettuce radicles more than 60%, followed by Alocasia macrorrhiza, Iris pallida, Terminalia triptera, Wrightia tomentosa, Cymbidium aloifolium, Garcinia villersiana and Kaempferia parviflora. The candidate species were subjected to further studies to identify the volatile allelochemicals in the volatile constituents.

Viola calcarata L. and Viola dubyana Burnat ex Gremli hydrolates: DI-SPME-GC-MS analysis and biological activity evaluation

“…However, its interaction (additional or synergistic) with other components such as thymol [Azirak & Karaman, 2008;Nasrollahi et al 2018;Mohammedi, 2021], α-pinene [Luiza Ishii-Iwamoto et al 2012] and 2-propen-1-ol [Ye et al 2016], capable of inhibiting the germination of weed seeds even at low concentrations, is not to be underestimated and could partially explain the different activity between the two hydrolates. Other compounds such as δ-2-carene, trans-sabinene hydrate, bisabolol oxide II and benzophenone were identified among the major constituents of essential oils with proven phytotoxic properties [Salomé Kpoviessi et al 2009;Tilaki et al 2013;Kinga et al 2014;Sothearith et al 2021]. Antiradical activity.…”

Novel and holistic approaches are required to realize allelopathic potential for weed management

“…Specific allelochemical compounds are also linked with traditional medicines, for example artemisinin (or ‘ Qinghaosu ’) from sweet wormwood ( Artemisia annua ) (Knudsmark Jessing et al, 2014), a traditional treatment for fever in China (Klayman, 1985). This trend has been explored more widely (Islam, Yeasmin, et al, 2018), in broad screens of a large range of species, followed by recommendations of suitable candidates for further work (Fujii et al, 2003; Islam, Hasan, et al, 2018; Sothearith et al, 2021; Suwitchayanon et al, 2017), while other medicinal species have been explored in more detail (Islam & Kato‐Noguchi, 2013). In spite of this work, medicinal plants remain far from commercialization for allelopathic benefit.…”

“…Many of the medicinal plants examined for allelopathic potential are of tropical origin (e.g., Sothearith et al, 2021; Suwitchayanon et al, 2017). Ooka and Owens (2018) hypothesized that tropical conditions may be particularly conducive to the evolution of allelopathic potential given otherwise favorable growing conditions and great plant diversity.…”

Antioxidant activity and chemical composition of Spirolobium cambodianum Baill.

“…6 In addition, dried stem samples of this species also indicated very low effects for allelopathic potentials. 7,8 To the limitation of our knowledge, no further reports have been on biological activity, especially the chemical constituents of S. cambodianum species. Hence, this study contributes to understanding this species' chemical composition and antioxidant activities.…”