An assessment of growth, floral morphology, and metabolites of a medicinal plant Sida cordifolia L. under the influence of elevated ozone

Tropospheric ozone (O₃) is a major secondary air pollutant and greenhouse gas, and its impact on growth, yield, and its quality is well established in the case of crop plants. However, the effects of tropospheric O₃ have not been comprehensively studied on medicinal plants. Therefore, a field study was planned on a medicinally important Sida cordifolia L. plant (commonly known as country mallow or Bala) to assess the expected changes on the morphology, growth, and leaf injury under elevated O₃ (ambient + 20 ppb) by using open-top chambers (OTCs) at 30, 60, and 90 days after treatment (DAT), while leaf and root metabolites were observed at 60 DAT. At all the growth stages, significant leaf damage was recorded as foliar injury symptoms. Most of the growth parameters also showed significant reductions at all the growth stages. Plants under elevated O₃ showed a significant negative impact on most of the reproductive parts of the plant. Leaf weight ratio (LWR) showed significant increment at early stages while reduced at 90 DAT; however, root shoot ratio (RSR) showed a significant reduction at 60 DAT. The majority of the steroid metabolites showed an increase in root and leaves under elevated O₃, while terpenes showed variable response. Due to O₃ stress, most of the major metabolites showed an increase possibly due to their role in defense and other metabolic activities. Based on the outcomes, it is concluded that the future increase in the levels of tropospheric O₃ will impact a significant effect on important metabolites of medicinal plants growing in tropical countries like India.

In-Vitro dual inhibition of protein glycation, and oxidation by some Arabian plants

Background

Diabetes mellitus is a metabolic disorder of epidemic proportion, projected to become the major cause of morbidity and mortality in the world in future. Despite extensive research in understanding this disease at molecular level, and the discovery of new drugs, diabetes and its complications remain largely untreated. Many of the late diabetic complications are associated with the glycation of proteins in the body. Natural flora has long been a rich source for therapeutic agents, especially against diabetes. The present study deals with the anti-glycation properties of some medicinally important plants of Arabian region.

Methods

Twenty-six medicinal plants, commonly found in different regions of Arabian Peninsula, were evaluated for their protein anti-glycation activity by using BSA-MG glycation assay in-vitro. The extracts were incubated with BSA and MG at 37 °C for 9 days, each sample was then examined for the presence of fluorescence (λex 330 nm, and λem 420 nm), which represent the extent of protein glycation. Antioxidant activity was evaluated by using 1,1-diphenyl- 2-picrylhydrazyl (DPPH), iron chelation, and superoxide radical scavenging asaays.

Results

The data revealed that out of 26 medicinal plants, five plants viz. Sida cordifolia, Plumbago zeylanica, Tribulus terrestris, Glycyrrhiza glabra, and Rosa indica were active against the in-vitro protein glycation with IC₅₀ values between 0.408- 1.690 mg/mL. Among the active plants, Glycyrrhiza glabra L. was found to be the most potent (IC₅₀ = 0.408 ± 0.027 mg/mL), followed by Rosa indica (IC₅₀ = 0.596 ± 0.0179 mg/mL), and Sida cordifolia L. (IC₅₀ = 0.63 ± 0.009 mg/mL). The antioxidant potential of these plant extracts were also determined by using DPPH (2,2-diphenyl-1-picrylhydrazyl), iron chelation, and superoxide anion radical scavenging assays. Among five plants, Sida cordifolia exhibited a potent anti-oxidant activity in both DPPH and superoxide anion radical scavenging assays (IC₅₀ = 0.005 ± 0.0004, and 0.078 ± 0.002 mg/mL, respectively), followed by Rosa indica (IC₅₀ = 0.023 ± 0.0005 and 0.141 ± 0.003 mg/mL, respectively).

Conclusions

Protein glycation in hyperglycemic conditions involve oxidative changes. Therefore dual inhibition of protein glycation and oxidation are desirable properties in any test substance investigated for therapeutic purposes.