Micropropagation and essential oil characterization of Plectranthus amboinicus (Lour.) Sprengel, an aromatic medicinal plant

Abstract

Plectranthus amboinicus (Loureiro) Sprengel is a therapeutically valued herb highly sought by various industries. This has led to its uncontrolled harvest from the wild leading to the risk of extinction. As an alternative, commercial propagation of P. amboinicus is desirable to avoid further depletion of wild populations. This paper describes the establishment of an efficient protocol for the multiplication, rooting and acclimatization of P. amboinicus. The greatest frequency of shoot multiplication of P. amboinicus was on semi-solid Murashige and Skoog (MS) medium supplemented with 0.4 mg L−1 6-benzylaminopurine (BAP). Media supplemented with higher concentrations of BAP or used in combination with gibberellic acid (GA3) produced abnormal plantlets. Optimal rooting was observed on plantlets cultured in half strength MS medium. Acclimatization was achieved by transferring the rooted plants onto sterile peat-moss moistened with MS medium and exposed to the glasshouse environment gradually over a period of 2 months. P. amboinicus responded readily to tissue culture, but careful attention was required to media formulation to avoid abnormal plantlet development.The composition of essential oils extracted from field grown plants and in vitro microshoots were comparable.

In vitro cultivation of tansy (Tanacetum vulgare L.): a tool for the production of potent pharmaceutical agents

“…Interestingly, in vitro cultivation significantly affected EO composition that may be favored by the high chemical plasticity reported for tansy (Lawrence 2000). Like in some other reports (Arumugam et al 2020), in EO obtained from in vitro cultivated plants, a significantly greater number of chemical compounds was detected, as compared to that of wild-grown tansy (88 vs. 65, respectively). In vitro cultivation conditions also enhanced the accumulation of sesquiterpenes with respect to EO from field-grown "mother" plants, with a similar portion of identified monoterpene and sesquiterpene compounds.…”

Volatile chemical composition of Colombian Plectranthus amboinicus (Lour.) Spreng essential oil and its biocidal action against Tribolium castaneum (Herbst)

“…The chemical composition in this study differs slightly from the results obtained through other essential oils of P. amboinicus from other countries, i.e., in the EO from Paraiba, Brazil, where the principal compounds found were carvacrol (33.50), p-cymene (28.20%) and γ-terpinene (14.77%). While a study in India reported the caryophyllene, caryophyllene oxide, aromadendrene oxide, and selinene as the majority components (Vishnu et al, 2021), in Malaysia the main constituents of the P. amboinicus EOs were carvacrol (43-45%), g-terpinene (11-16%), and p-cymene (12-16%) (Arumugam et al, 2020), and in Taiwan, these were was carvacrol (61,5%), β-Caryophyllene (12.79%), γ-terpinene (8.51%) and p-cymene (9.42%) (Huang et al, 2019). The variation in the proportion and yield percentage of essential oils and their chemical composition can be due to the influence of agroecology and environmental conditions (Aguiar et al, 2015).…”

Micropropagation and Acclimatization of Common Oregano (<i>Origanum vulgare</i> L. Subsp. <i>vulgare</i>) by Shoot Tip Culture

“…Integration of GA 3 alone or in combination with cytokinins or/and auxins is reported in several species of Lamiaceae. Arumugam et al (2020) [44] found that the combination of 4.44 µM BAP and 2.89 µM GA 3 allowed maximum elongation and shoot multiplication of Plectranthus amboinicus (Lour.) Sprengel, but generated a high percentage of vitroplants with abnormal morphological characters.…”