生药学与天然产物杂志

Lysimachia ramosa is a traditional medicinal plant, consumed by different tribes of northeast India to cure intestinal helminth infections. In order to measure the toxic effects of the plant on its consumer, if any, the present in vivo study was carried out on mice using sub-lethal doses of crude ethanol extract viz. 100 and 200 mg/kg body weight for 14 days. Surface topographical and ultrastructural observations on liver, kidney and intestine of treated mice revealed marked deformation and destruction accompanied by quantitative changes in liver and kidney markers like aspartate aminotransferase, alanine aminotransferase and creatinine in comparison to the control mice. The results showed that consumption of crude plant extract at a dose 100 mg and above per kg body weight continuously for long time may cause toxic effects to its consumer.

Pathogenic diseases are widespread across the globe. Due to the emergence of new resistant pathogenic strains, as well as the formation of side effects by the continuous use of commercial antibiotics, there is a pressing need to identify new antimicrobial agents from natural resources. Several reports are available on the antimicrobial effects of whole plants or specific macroscopic parts of the plants. However, several microscopic parts are well recognized as containing potential antimicrobial agents, which in turn, are accountable for the antimicrobial activity of the entire plant or some part of it. Interestingly, very limited studies are available on the antimicrobial activity of any microscopic part of the plant. In the interim, several studies are present on the antimicrobial activity of an individual plant or part. But studies dealing with the synergistic effect of different species are very rare. The current study demonstrates the outstanding antimicrobial activity of the microscopic epidermal glands present in the leaves of two primitive terrestrial vascular plants, Thelypteris parasitica (L.) Fosberg and Cyclosorus interruptus (Willd.) H. Ito (Thelypteridaceae: Pteridophyta), and their significant synergistic effects.

The antimicrobial activity of honey depends on many factors, including its botanical origin, geographical and entomological source. The aim of this study was to evaluate and compare the antimicrobial potential of honey varieties from Apis mellifera, Hypotrigona sp. and Melipona sp. against MDR Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa ATCC 25783, Candida tropicalis, Candida albicans SC 5314 and Cryptococcus neoformans. By using standard microbiological procedure, the agar-well diffusion and broth microdilution methods were used to evaluate honey samples for their antimicrobial and non-peroxidase activity. Different concentrations of the honey samples showed inhibition zones diameter (mm) against the test isolates. The Minimum Inhibitory Concentrations (MICs) of the honey varieties from A. mellifera, Hypotrigona sp. and Melipona sp. ranged from 6.3–25.0%, 3.1–12.5% and 6.3–25.0% (v/v) respectively. There were no statistically significant differences between the mean MICs of honey varieties against E. coli, P. aeruginosa (ATCC 25783) and C. neoformans. Hypotrigona sp. honey had the least mean MICs (4.15 ± 1.58–11.11 ± 2.76 % v/v) against most of the test organisms. The Minimum Biocidal Concentration (MBC) of the honey varieties from A. mellifera, Hypotrigona sp. and Melipona sp. against the test organisms varied from 6.3–50%, 3.1–25% and 12–50% (v/v) respectively. There were no significant differences between the mean MBCs of the honeys against MDR S. aureus (p=0.179), E. coli (p=0.564), P. aeruginosa (ATCC 25783) (p=0.846), and C. albicans (SC5314) (p=0.264). The honeys had some levels of non-peroxidase activity against E. coli, P. aeruginosa (ATCC 25783) and C. neoformans. This study has scientifically authenticated the potential use of stingless bee honeys from “Okotobo and Ifufu” as complementary therapeutic agents.

The Natural Herbal Oil Formulation (NHOF) have been designed to work against White Spot Syndrome Virus (WSSV) in Shrimp. The essential oil blend extracted from the following plants, Lavandula latifolia, Pinus sylvestris, Jasminum officinale, Citrus limon, Prunus avium, Viola odorata, Gardenia jasminoides, Cocos nucifera, Rosa damascene and Eucalyptus globulus, mixed together to develop as anti-WSSV product. The product were added in the feed, as feed additive. Another product developed which was applied in tank water as water supplement named as “Pondguard” (Reg no. KKP RI no. D16060285-HBC). The Pondguard is composed of three essential oils i.e., Eucalyptus globulus, Pinus sylvestris and Lavandula latifolia. A bioassay trial was conducted to determine the efficacy of developed formulation as an anti-WSSV candidate. The experimental shrimp was fed on NHOF-mixed feed and “Pondguard” applied in the tank water whereas control shrimp were fed on the regular feed. The shrimp of both experimental and control were challenged by WSSV on 15th day of feeding. Two methods of WSSV challenge were applied, per-os challenge and immersion challenge. The cumulative mortality in positive control reached up to 100% on DPI 10 whereas no mortality appeared in the experimental group and in negative control. The trial results show that the developed natural herbal formulation has significant effect against WSSV in a controlled condition.