New Caledonia: A Hot Spot for Valuable Chemodiversity Part 3: Santalales, Caryophyllales, and Asterids

Abstract

The flora of New Caledonia encompasses more than 3000 plant species and an endemism of almost 80%. New Caledonia is even considered as one of the 34 'hot spots' for biodiversity. Considering the current global loss of biodiversity and the fact that several drugs and pesticides become obsolete, there is an urgent need to increase sampling and research on new natural products. In this context, here, we reviewed the chemical knowledge available on New Caledonian native flora from economical perspectives. We expect that a better knowledge of the economic potential of plant chemistry will encourage the plantation of native plants for the development of a sustainable economy which will participate in the conservation of biodiversity. This review is divided into three parts, and the third part which is presented here summarizes the scientific literature related to the chemistry of endemic santalales, caryophyllales, and asterids. We show that the high rate of endemism is correlated with the originality of phytochemicals encountered in New Caledonian plants. A total of 176 original natural compounds have been identified from these plants, whereas many species have not been investigated so far. We also discuss the economic potential of plants and molecules with consideration of their medicinal and industrial perspectives. This review finally highlights several groups, such as Sapotaceae, that are unexplored in New Caledonia despite the high chemical interest in them. These plants are considered to have priority in future chemical investigations.

Linking phytochemistry to traditional uses and pharmacology of an underexplored genus – Psydrax: a review

“…Out of the 22 iridoids so far isolated from P. subcordata, (21) is observed to be the most common and widely distributed iridoid of the species; it was isolated as the major component of the methanol extract of dry fruits and stem bark of P. subcordata . Another species that yielded iridoids is P. odorata ; its leaf and bark produced four glycosidic iridoids (23–26) , in company with other non-iridoid constituents (Coulerie and Poullain 2016 ; Sévenet and Pusset 1996 ). These data on iridoids suggest that the genus accumulates high amounts of this class of metabolites which may be of taxonomic relevance in plant systematics if further investigation is carried out.…”

“…On the contrary, some other research groups identified alkaloids in a different part of P. subcordata, P. horizontalis, P. schimperiana and P. dicoccos , but they reported the alkaloid content of P. schimperiana and P. dicoccos to be small (Anokwah et al 2016 ; Feenna et al 2020 ; Ochwang’i et al 2016 ; Umaiyambigai et al 2016 ). To confirm the presence of alkaloids in Psydrax , three alkaloids: two monoterpene alkaloids (40 and 41) and a peptide alkaloid (42) were isolated from P. odorata bark and leaf (Coulerie and Poullain 2016 ) and their structures are given in Fig. 4 .…”

Antimicrobial activity of Xylopia pancheri Baill. Leaf extract against susceptible and resistant Staphylococcus aureus

“…source of bioactive compounds, and more than 80 antibacterial drugs deriving from NPs were approved by the FDA between 1981 and 2014 (Newman & Cragg, 2016). New Caledonia is considered as a major "hot spot" for terrestrial biodiversity with 3,200 native species and 78% of endemism representing a valuable source of bioactive NPs (Coulerie & Poullain, 2016). Xylopia pancheri Baill.…”

“…(Annonaceae) is an endemic shrub that grows on peridotite ground of New Caledonia (Johnson, Munzinger, Peterson, & Murray, 2013;Morat et al, 2012;Munzinger et al, 2016;Turner & Utteridge, 2017), and, to the best of our knowledge, only one study has characterized the chemical composition of the plant leaves and bark extracts and none of their biological activities (Niéto, Sévenet, Leboeuf, & Cavé, 1976). Total leaf extract and alkaloid fraction of X. pancheri were shown to exert light peripheral vasodilatory activity in mice but no experimental demonstration was presented (Coulerie & Poullain, 2016;Sévenet & Pusset, 1996). Herein, we investigated the antibacterial activities of X. pancheri leaf extracts (XPLEs) against (i) susceptible S. aureus and MRSA, and (ii) extended-spectrum-β-lactamase (ESBL)-producing Pseudomonas aeruginosa.…”