Fresh R. spathacea leaf samples were obtained from Petaling
Jaya, Malaysia. The identity of the plant was confirmed by Dr
Wong Khoon Meng, former professor of Botany, Institute of
Biological Sciences, University of Malaya. They were freezedried in a freeze dryer (Christ Alpha 1–4 unit) for 48 hours,
and weighed before and after drying to determine the moisture
content. Bacterial isolates were obtained from American Type
Culture Collection (ATCC), with the exception of Serratia
marcescens and Proteus vulgaris, which were obtained from
Institute of Medical Research (IMR), Malaysia. All bacteria
were grown on nutrient agar, with the exception of Neisseria
gonorrhoeae, which was grown on chocolate II agar with
haemoglobin