Evaluation of Allelopathic Potentials from Medicinal Plant Species in Phnom Kulen National Park, Cambodia by the Sandwich Method

Abstract

Phnom Kulen National Park, in north-western Cambodia, has huge richness in biodiversity and medicinal value. One hundred and ninety-five (195) medicinal plant species were collected from the national park to examine allelopathic potentials by using the sandwich method, a specific bioassay for the evaluation of leachates from plants. The study found 58 out of 195 medicinal plant species showed significant inhibitory effects on lettuce radicle elongation as evaluated by standard deviation variance based on the normal distribution. Three species including Iris pallida (4% of control), Parabarium micranthum (7.5% of control), and Peliosanthes teta (8.2% of control) showed strong inhibition of lettuce radicle elongation less than 10% of the control. The results presented could present as a benchmark for isolation and identification of allelochemicals among medicinal plants used in Cambodia.

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

“…Iris pallida, known as the sweet iris, is a perennial herb native to the Dalmatian coast, Croatia; it is mostly cultivated for its essential oils and use in aromatherapy and traditional medicine [34,35]. The rhizomes of Iris pallida found to have strong allelopathic activity contain the isoflavones irigenin, iristectorigenin A, nigericin, nigricanin, irisflorentin, iriskumaonin methyl ether, irilone, iriflogenin and others [23,[36][37][38][39]. In total, 16 and 26 volatile components were found from the essential oil of rhizomes and leaves, respectively.…”

“…Some bioactive substances, including ferulic, coumaric, vanillic, caffeic and chlorogenic acids in medicinal plants have been found to inhibit plant growth [21,22]. By using the sandwich method, the previous study identified more than fifty medicinal plants with allelopathic potentials through leachates [23]. This study, therefore, collected different parts of some medicinal plants from northwestern Cambodia to examine allelopathic effects using the dish pack method under laboratory conditions.…”

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.…”

“…(2013) showed the methanolic stem extract of this species displayed good antioxidant activity in DPPH and ORAC assay 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.…”

Exploring the use of chamomile (Matricaria chamomilla L.) bioactive compounds to control flixweed (Descurainia sophia L.) in bread wheat (Triticum aestivum L.): Implication for reducing chemical herbicide pollution

“…Many medicinal plants have been reported to have allelopathic compounds, and their extracts have been used to suppress weeds ( Sothearith et al, 2021 , Sothearith et al, 2021 ; Kyaw et al, 2022 ). For example, it is reported that the extract of Ocimum gratissimum , Chromolaena odorata , Ageratum conyzoides , and Eclipta alba have allopathic potential ( Appiah et al, 2017 ).…”