This paper evaluates the antioxidant potential of 22 species of medicinal plants from Malaysian Rubiaceae. The ferric thiocyanate (FTC), thiobarbituric acid (TBA), total phenolic content (TPC) and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were employed. The tested extracts showed strong antioxidant potential when compared to butylated hydroxytoluene (BHT), quercetin and vitamin E with percent inhibition of 91-99% in the FTC, and 77-97% in the TBA assays. The TPC of extracts found varied from 8.55 to 120.63 mg GAE /g PE. Psychotria griffithii and Hydnophytum formicarum showed total phenolic content of more than 100 mg GAE/gPE and strong DPPH radical-scavenging activity with IC 50 values of 14.0 and 22.4 µg/ml, respectively. The standard vitamin C and BHT showed IC 50 values of 12.8, and 5.6 µ µ µ µg/ml, respectively. A good correlation was observed between total phenolic content and radical-scavenging activities. The medicinal plants in this study tested are expected to be good sources of natural antioxidants.

Abstract. Daud D, Dewa MSAM, Mahbob ENM, Razak WRWA. 2021. Short Communication: Phytochemical diversity and bioactivity of Malaysian Premna cordifolia (Lamiaceae). Biodiversitas 22: 3245-3248. The aims of the present study are to determine the chelation potential and protective effect of Premna cordifolia leaves ethanolic extract in lead intoxicated mice. Twenty-four male mice were divided into four groups with six animals each. Group 1 was healthy mice and received 2 ml/kg bwt distilled water. Group 2 was healthy mice and supplemented with 200 mg/kg bwt P. cordifolia leaves ethanolic extract. Group 3 was lead intoxicated mice and received 2 ml/kg bwt distilled water. Group 4 was lead intoxicated mice and supplemented with 200 mg/kg bwt P. cordifolia leaves ethanolic extract. All treatments were given for 14 days. Chelation activity was determined by measuring the concentrations of lead in the liver, kidney and testis by using atomic absorption spectroscopy. Sperm quality was tested according to World Health Organization manual and testosterone was estimated by using ELISA kit. Spectroscopic data showed that P. cordifolia leaves ethanolic extract was able to lower lead concentrations in liver, kidney and testis of lead intoxicated mice. Following a decrease in lead concentrations, sperm quality and testosterone levels were restored in lead intoxicated mice supplemented with P. cordifolia leaves ethanolic extract. In conclusion, P. cordifolia leaves ethanolic extract has the potential to be developed as an alternative remedy for treating lead poisoning effects.

ABSTRACT. This work explicates a simple, rapid, and sensitive method for the electrochemical detection of dopamine (DOP) utilising 1-phenyl-3-methyl-4-orthofluorobenzoyl-5-pyrazolone (HPMoFBP)/multiwalled carbon nanotube (MWCNT) carbon paste electrode (CPE). The electrochemical behaviour of DOP was performed through cyclic voltammetry and square wave voltammetry. HPMoFBP/MWCNT showed a higher current at the lower potential for the oxidation of DOP compared to bare MWCNT. The sensor's improved electrocatalytic activity was observed to detect in a 1.0 x 10-1 M phosphate buffer saline (PBS) solution at pH 8.0. A good linear regression analysis was observed between electrical response and the concentration of DOP in the range of 1 to 1000 µM. Under optimized experimental conditions, 1.0 x 10-7 M has been determined as the limit of detection (LOD). The sensor has expressed considerable sensitivity towards DOP detection without interference and is successfully used to determine DOP in dopamine hydrochloride injection.   KEY WORDS: Electrochemical sensor, Dopamine, Pyrazolone, MWCNT, Voltammetry Bull. Chem. Soc. Ethiop. 2023, 37(4), 845-857.                                                             DOI: https://dx.doi.org/10.4314/bcse.v37i4.4

Hedyotis spesies have been used in Chinese folk medicine as a treatment for colds, stomatitis and various inflammations. In this study, three methanolic extracts of Hedyotis species (Hedyotis corymbosa, Hedyotis havilandii and Hedyotis philippinensis) were screened for their anti-inflammatory activity. The plant extracts along with asperuloside, the marker compound of H. philippinensis were tested for their anti-inflammatory effect against lipopolysaccharide (LPS) and interferon- (IFN-)-induced nitric oxide (NO) production using RAW264.7 macrophage cells. Among the three species, H. philippinensis (leaves and stems) showed good NO radical inhibitory activity (with IC50 values of 139.76±12.50 and 176.21±2.48 g/ml, respectively). Asperuloside, isolated as a major compound from the plant moderately inhibited LPS/IFN--induced NO production by 63% at a concentration of 100 M (45% cell viability) compared to L-NAME (77 %). Its IC50 value was found to be 75.45±2.25 M. Its inhibition was also found to be dose-dependent.