Records of Natural Products Articles

MMatricaria recutita L. and Achillea millefolium L. (Astereacea) aetherolea are among the herbal drug preparations used due to their broad-spectrum antimicrobial effects. The present study aimed to evaluate the in vitro antibacterial activity of M. recutita and A. millefolium oils individually combined with tetracycline. Followed by safety/toxicity evaluation using an in vivo animal alternative experimental model, namely Caenorhabditis elegans. Chemical verification of Pharmacopoeia quality essential oils was performed both by GC-FID and GC-MS systems, simultaneously. β-Caryophyllene (17%), β-pinene (13.2%), camphor (10%), and sabinene (9.7%) were identified as major components for A. millefolium essential oil; whereas, bisabolol oxide A (41.6%), α-bisabolol (19.4%), (E)-β-farnesene (17%), α-bisabolol oxide B (5.2%), α-bisabolon oxide A (5%), chamazulene (1.6%), and germacrene D (1.2%) were determined as major components for M. recutita essential oil, respectively, in line with the international standards. Antibacterial activities of essential oils and tetracycline were evaluated by microdilution methods against the standard pathogenic strains Bacillus cereus NRRL B3711, Corynebacterium striatum ATCC BAA-1293, Streptococcus sanguinis ATCC 10556, Staphylococcus aureus ATCC 700699. Minimal inhibitory concentrations (MIC) were determined followed by the checkerboard combination studies. A. millefolium and M. recutita essential oils showed in vitro inhibitory activity against all tested microorganisms (MIC= 48.7-6250 μg/mL). The oil combinations with tetracycline showed varying inhibitory antibacterial activity, where M. recutita essential oil with tetracycline resulted in synergism against S.aureus. In vivo toxicity tests on C. elegans nematodes resulted in a non-acute toxicity, indicating the relatively safe use of the tetracycline combinations.

A previously undescribed polyketide (1) and four known compounds (2-5) isolated from the endophytic fungus Fusarium tricinctum from Fritillaria monantha. Compound 1 showed anti-inflammatory activity by inhibiting NO production with an IC50 value of 17.6±0.46 µM.

Obesity is a widespread public health problem worldwide and is associated with numerous health risks, requiring effective prevention and treatment strategies. Although synthetic anti-obesity drugs are available, they often cause adverse side effects, thus generating interest in natural products as safer and more effective alternatives. Malaysian shrub plants thrive in the country’s tropical climate and offer a rich source of biological active compounds with potential anti-obesity effects. Several studies, including in vivo and clinical trials, have reported promising anti-obesity effects of these plants. Research on local plants not only aligns with public health priorities but also provides affordable interventions for the local population. This review systematically summarizes findings from 193 articles across electronic databases using relevant keywords, covering Malaysian herbaceous and shrub species with anti-obesity potential, their isolated compounds, proposed mechanisms of action, and supporting in vitro, animal model, and clinical evidence. In addition, toxicological data are discussed to provide a comprehensive perspective of the therapeutic potential of these plants. This review highlights the gaps in current knowledge and proposes future directions for leveraging Malaysian plants to combat obesity.

A new clerodane-type diterpene, conbliate C (1), along with three known analogues (2−4), were isolated from Conyza blinii Levl. The structure of the new compound was elucidated on the basis of detailed spectroscopic analysis. The cytotoxic effects of the isolated compounds on two human tumors cell lines (AsPC-1 and HepG-2) were evaluated by the MTT assay.

Two new diketopiperazine alkaloids, namely simplicamides A (1) and B (2), were isolated from the deep-soil derived fungus Penicillium simplicissimum GZWMJZ-1612. The structures of these two compounds were determined by NMR, HRESIMS, ECD calculation, and Marfey’s method. Compound 1 exhibited potent antioxidant capacity of ORAC and DPPH scavenging ability. Compound 2 displayed significant ORAC scavenging ability and α-glucosidase inhibitory activity.

Lignans, such as podophyllotoxin, schisandrin, and silymarin, are known for their notable biological activities. In our study, a new lignan, named melaleucin D (1), was isolated from the leaves and stems of the plant Melaleuca bracteata F. Muell. The planar structure was determined by combining 1H NMR/13C NMR/ COSY/HSQC/HMBC spectra and HRESIMS data. The absolute configuration was established by comparing the experimental circular dichroism (CD) data with the calculated theoretical ECD data. Compound 1 contained an unusual dioxane moiety. The antibacterial assay revealed that compound 1 did not exhibit a zone of inhibition against Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 25922 at a concentration of 256 mg/mL.

The consumption of raspberry (Rubus idaeus L.) leaves has a long tradition, especially as a "general pregnancy tea", although the scientific data are insufficient and contradictory. Phytochemical comparation of extracts from cultivated and wild raspberry leaves, in silico prediction of their biological activities and acute toxicity followed by in vitro antiradical activity and effects on the viability/proliferation of HeLa cells and isolated rat uterus were performed. Leaves from cultured (v. Polka) and wild individuals were extracted with distilled water, 70% v/v ethanol or 70% v/v methanol. All samples exhibited high polyphenol content and antiradical activity, with the 70% v/v ethanol extract of wild R. idaeus showing the strongest free radical scavenging ability. In silico analyzes predicted that a large number of raspberry leaves possess anti-inflammatory, apoptosis-agonistic, antinociceptive and NO signaling-related activities. Potentially toxic levels of the tested compounds could not be achieved with regular tea drinking. The tested extracts have no noticeable effects on the viability/proliferation of HeLa cells. The effects on spontaneous contraction of the isolated rat uterus were modest. Although safety is not a concern, further studies are needed to justify or deny the efficacy of raspberry leaf tea in folk medicine for healthy pregnancy and easy delivery.