The influence of photoselective shade netting on vegetative growth and bioactivity of Myrsine africana L. for cosmeceutical production

Abstract

As the global desire for natural remedies derived from botanicals increases, the pressure on plant populations and biodiversity intensifies. Therefore, to conserve biodiversity as a valuable genetic and biochemical resource, sustainable utilisation and commercial production should be prioritised. Myrsine africana L. (MA), has recently been found to possess significant cosmeceutical properties, such as elastase inhibition (anti-wrinkle) and anti-tyrosinase (skin even tone) activity. However, this species is relatively slow growing, recalcitrant to adventitious root (AR) development, and has slightly insufficient bioactivity in raw extracts. These factors reduce the economic feasibility of producing this commercially valuable indigenous species. Consequently, this may enhance wild harvesting of this species, placing pressure on wild populations. Manipulation of light is a common practice in plant production to exploit plant growth and development, as light quantity and quality effectively influence the primary and secondary metabolism of plants. Therefore, the current study aimed to investigate the influence of selected photoselective shade net on vegetative growth and metabolites of MA shoot material. Results displayed significantly enhanced growth (p < 0.001) under green (50 % density), black (50 %) and red (80 %) shade net in comparison to the control (cultivation under full sun) and inhibited growth under blue (50 %) shade net. Shade net effectively influenced starch and soluble carbohydrate content. Furthermore, significantly higher elastase inhibition was observed under green and red shade net treatments in comparison to the control in autumn, with IC50 values of 18.59 μg/mL, 19.28 μg/mL and 37.93 μg/mL, respectively. In addition, bioactivity was significantly higher in autumn (p < 0.001) under green, red and control treatments. It can be concluded that photoselective shade net may be used to enhance plant growth and bioactivity of MA.