Chemical composition, antioxidant activity and bioactive constituents of six native endangered medicinal orchid species from north-eastern Himalayan region of India

Bioactive compounds in Laelia speciosa (Orchidaceae) seedlings grown in temporary immersion bioreactor

“…There are also no studies that determine the concentration of antioxidants directly in flowers, leaves, stems and roots of L. speciosa. The concentration of total polyphenols has been reported in other orchids, such as in Epidendrum secundum (leaves) with 4.03 mg GAE/g (Cazar et al, 2023), in extracts of Dendrobium sp., A. graminifolia and Coelogyne with 5-40 mg GAE/g (Natta et al, 2022), in Dendrobium flowers with 5.34 mg GAE/g (Athipornchai & Jullapo, 2018), in Habenaria edgeworthii with 14.3 mg GAE/100 g (Giri et al, 2012) and in Malaxis acuminata with 7.82-32.59 mg GAE/g (Bose et al, 2017). It is worth noting that the antioxidant capacity observed in this study exceeded the 9 % reported for Eulophia macrobulbon roots (Schuster et al, 2017).…”

“…This fact is not unusual given that orchids have been recognized as synthesizers and accumulators of various bioactive compounds, including alkaloids, saponins, carotenoids, flavonoids, and polyphenols, within their cellular and tissue structures. The presence of these compounds suggests potential medicinal properties (Natta et al, 2022). These compounds play a vital role in scavenging reactive oxygen species, including hydroxyl, peroxyl, hypochlorous acid, superoxide anion, and peroxynitrite radicals, which are associated with cell damage and diseases (Giri et al, 2012).…”

“…The choice of solvent for extracting antioxidants can significantly influence the types and concentrations of compounds recovered. Various extraction solvents have been reported in the literature, including chloroform, acetone, methanol, and ethanol (Cazar et al, 2023;Natta et al, 2022;Bose et al, 2017), and the yields can vary depending on the plant species and the plant part used for extraction. In this study, we employed water from the L. speciosa culture medium as the solvent for extraction.…”

“…Some molecules, such as flavonoids, alkaloids, tannins, and enzymes with anticollagenase, anti-cyclooxygenase, or anti-elastase properties, have been reported in orchids such as Epidendrum secundum, Dendrobium nobile, D. moschatum, A. graminifolia, Coelogyne nitida, Dendrobium spp., Eulophia hereroensis, E. petersii, Ansellia africana, Bulbophyllum scaberulum, Cyrtorchis arcuata, and Malaxis acuminata (Chinsamy et al, 2014;Bose et al, 2017;Athipornchai & Jullapo, 2018;Natta et al, 2022;Cazar et al, 2023). Additionally, vasorelaxant effects have been observed in L. speciosa and L. anceps (Vergara-Galicia et al, 2013).…”

Therapeutic Potential of Phenolic Compounds in Medicinal Plants—Natural Health Products for Human Health

“…The Althaea officinalis extracts showed stronger antioxidant activity and excellent α-glucosidase, 5-lipoxygenase, and nitric oxide inhibitory properties [ 131 ]. Dendrobium densiflorum was rich in flavonoid, alkaloid, and antioxidant activity, Acampe papillosa was rich in total phenol, total tannin, and total saponin content, and Coelogyne nitida exhibited higher antioxidant activity because of its higher quercetin content [ 132 ]. Cirak et al [ 133 ] showed that Achillea arabica Kotschy is an important source of natural antioxidants.…”