Melastoma malabathricum is a well-known herb in Malaysia where it being used in various ways for treatment of different diseases and ailments including skin problems. The study aims to investigate acute and subacute dermal toxicity of ethanolic extract of M. malabathricum leaves following to a single or repeated doses exposure. A total of 30 female Sprague-Dawley rats were grouped into 5 groups (n = 6 per group) for both acute and subacute toxicity study. The duration for each study was determined at 14 days for acute toxicity and 28 days for subacute toxicity. The rats were topically applied with the plant extract at three different doses; 2.5%, 5.0% and 10.0% on the shaved area of dorsal skin. For acute toxicity study, rats in all three groups received single application of the extract on the first day of the experimental period, while rats in subacute toxicity study were topically applied with the extract once daily for 28 days. Throughout the respective 14-day and 28-day study periods, all rats were monitored for any changes in their physical appearance and behavioural patterns that might develop due to toxic effects of the plant. There were no mortality or abnormal physical appearance, and physiological and behavioural changes observed in all rats in both studies. Body weights, kidney and liver weights, and both haematology and serum biochemistry results showed no significant (p > 0.05) differences between all groups in both studies. All of the findings were supported by normal macroscopic and microscopic architectures of liver, kidneys and skin of all rats applied topically with the extract. This study suggests that topical application of M. malabathricum leaf ethanolic extract at 2.5%, 5% and 10% does not induce acute and subacute adverse effects on the skin or systemic toxic reactions in rats.
Most of the public health importance coronaviruses, such as Severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV-2 are likely originated from bats and spread to humans through intermediate hosts; civet cats, dromedary camel and Malayan pangolin, respectively. SARS-CoV-2-like coronaviruses were detected in Thailand, which is neighbouring with Kelantan in East Coast Malaysia. To date, there is no report on the presence of public health concerns (SARS-CoV, SARS-CoV-2 and MERS-CoV) coronaviruses in bats from Malaysia. This study was aimed to elucidate the presence of these coronaviruses in bat samples from East Coast, Malaysia. A total of hundred seventy oropharyngeal swab samples were collected from three states of East Coast Malaysia. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was conducted based on partial 3' Untranslated region (3'UTR) or ORF10 gene and the products were sequenced. The sequences were compared with all coronavirus sequences from the National Center for Biotechnology Information-GenBank (NCBI-GenBank) using NCBI-Basic Local Alignment Search Tool (NCBI-BLAST) software. A phylogenetic tree was constructed to determine the genetic relationship among the detected coronaviruses with the reference coronaviruses from the NCBI-GenBank. Our results showed that SARSCoV-2-like viruses were present in 3% (5/170) of the bats from East Coast Malaysia that have 98-99% sequence identities and are genetically related to SARS-CoV-2 from humans. This finding indicates the presence of SARS-CoV-2-like viruses in bats from East Coast Malaysia that may become a public health concern in the future.
Moringa oleifera (M. oleifera) Lam belongs to the family Moringaceae. It is an important multipurpose tree that is largely distributed globally and has been used almost in every aspect of traditional medicine for the treatment of various illnesses including cancers, diabetes mellitus, asthma, arthritis, etc. This study investigated the effects of oral acute and sub-acute administration of M. oleifera hydroethanolic leaf extract (MOHE) in ICR-mice. Its major phenolic compounds were also determined. Ten (10) female, 8-week old mice were grouped into control and treatment groups for acute toxicity study. A dose of 2000 mg/kg MOHE was given once to the treatment group via oral gavage. However, for the sub-acute toxicity study, 25 mice were grouped into groups A (control), B (125 mg/kg), C (250 mg/kg), D (500 mg/kg) and E (1000 mg/kg). MOHE was given via oral gavage to groups B, C, D and E daily for 28 days. Group A received only distilled water. The mice were sacrificed at the end of the experiments and samples were collected for evaluation. The results of the chemical profiling of MOHE revealed the presence of glucomoringin, niaziminine, quercetin and kaempferol as the major compounds. The treated mice in the acute toxicity study were slightly anaemic and showed evidence of stress leukogram. Moreover, a slight increase in creatinine, significant increases in AST and CK, hepatic degeneration and necrosis, none-obstructive sinusoidal dilatation, renal tubular necrosis, interstitial nephritis and renal interstitial oedema were observed. It is concluded that the LD50 of MOHE is higher than 2000 mg/kg. However, oral administration of MOHE causes acute mild anaemia and moderate hepato-nephrotoxicity in ICR-mice. Its major phenolic compounds are glucomoringin, niaziminine, quercetin and kaempferol.