With the advent of nanotechnology, many related industries rapidly developed over the recent past. Generally, top-down and bottom-up approaches are the two major processes used to synthesize nanoparticles; most of these require high temperatures, vacuum conditions, and harsh/toxic chemicals. As a consequence, adverse effects impacted organisms including humans. Some synthesis methods are expensive and time-consuming. As a corollary, the concept of “green nanotechnology” emerged with the green synthesis of nanoparticles commencing a new epoch in nanotechnology. This involves the synthesis of nanomaterial from microorganisms, macroorganisms, and other biological materials. Honey is documented as the world’s oldest food source with exceptional medical, chemical, physical, and pharmaceutical values. Honey mediated green synthesis is a relatively novel concept used during the past few years to synthesize gold, silver, carbon, platinum, and palladium nanoparticles. Honey acts as both a stabilizing and a reducing agent and importantly functions as a precursor in nanoparticle synthesis. This method usually requires room temperature and does not produce toxic byproducts. In conclusion, honey mediated green synthesis of nanoparticles provides a simple, cost effective, biocompatible, reproducible, rapid, and safe method. The special activity of honey functionalized nanoparticles may provide valuable end products with numerous applications in diverse fields.

Reports on malformations in amphibians due to trematode infections prompted this study on an endemic frog species in Sri Lanka. The effect of an infection with a monostome-type cercaria is reported here. Ten days post-hatch, tadpoles (Gosner stage 27) of the common hourglass treefrog Polypedates cruciger (Anura: Ranidae), were exposed to a monostome-type cercaria, in a dose-dependent manner, under laboratory conditions. Malformations, survival and growth of the tadpoles were monitored for four treatments having different doses of cercariae (control = 0, low= 16, intermediate = 32 and high = 48). The severity and the number of malformations varied depending on the dose of the infection. A higher percentage (90%) of malformations was observed at higher doses of cercariae. Overall, malformations in the limbs, spine and skin pigmentation were common after parasite exposure. Survival declined with increasing doses of parasite infections, declining to 88% in the high treatment group, although not statistically significant. The growth rates of tadpoles as measured by weight and snout to vent length showed that exposed individuals were significantly smaller and had higher variance in growth compared with that of the controls. Thus, this trematode infection significantly affected the growth and induced severe malformations in P. cruciger, under laboratory conditions. Such malformed tadpoles and adults may face high predation under natural conditions. Here, we present the first empirical evidence of the effect of a trematode infection on the development of malformations, growth and survivorship in an endemic amphibian species in Sri Lanka.

Herbal remedies have been practiced by humans over centuries and therefore possess time-proven safety. However, it is imperative to evaluate the toxic effects of herbal medicine to confirm their safety, particularly when developing therapeutic leads. Use of laboratory animals such as rats, mice, and rabbits was considered as gold standard in herbal toxicity assessments. However, in the last few decades, the ethical consideration of using higher vertebrates for toxicity testing has become more contentious. Thus, possible alternative models entailing lower vertebrates such as zebrafish were introduced. The zebrafish embryotoxicity model is at the forefront of toxicology assessment due to the transparent nature of embryos, low cost, short cycle, higher fecundity, and genetic redundancy to the humans. Recently, its application has been extended to herbal toxicology. The present review intends to provide a comprehensive assembly of studies that applied the zebrafish embryo model for the assessment of herbal toxicity. A systematic literature survey was carried out in popular scientific databases. The literature search identified a total of 1014 articles in PubMed = 12, Scopus SciVerse® = 623, and Google Scholar = 1000. After screening, 25 articles were included in this review, and they were categorized into three groups in which the zebrafish embryotoxicity assay has been applied to investigate the toxicity of (1) polyherbal formulae/medical prescription (2 full texts), (2) crude extracts (12 full texts), and (3) phytocompounds/isolated constituents (11 full texts). These studies have investigated the toxicity of 6 polyherbal formulae, 16 crude extracts, and more than 30 phytocompounds/isolated constituents using the zebrafish embryotoxicity model. Moreover, this model has explicated the teratogenic effects and specific organ toxicities such as the kidney, heart, and liver. Furthermore, in some studies, the molecular mechanisms underlying the toxicity of herbal medicine have been elucidated. This comprehensive collection of scientific data solidifies the zebrafish embryo model as an effective model system for studying toxicological effects of a broad spectrum of herbal remedies. Henceforth, it provides a novel insight into the toxicity assessment of herbal medicine.

Euphorbia hirta commonly known as Tawa-Tawa is a plant used in folklore medicine in the Philippines for the treatment of dengue. Though, E. hirta has been extensively investigated for numerous bioactivities, limited studies have been conducted on the antidengue activity. Thus, the present study provides a comprehensive review of studies conducted on the antidengue activity of E. hirta. A systematic literature survey was carried out in scientific databases, PubMed®, Scopus, and Google Scholar, for research carried on the antidengue activity of E. hirta. The literature search identified a total of 867 articles: databases PubMed = 6, Scopus SciVerse® = 423, and Google Scholar = 437; one additional article was identified by searching reference lists. Eight full papers were entitled to the review; out of those, two studies focused on ethnobotanical surveys, three on animal experiments, one on human trial, and two on in vitro antiviral activities, and one was computational study. The available evidence conclusively demonstrates the potential of E. hirta against dengue as it holds significant antiviral and platelet increasing activities. However, the number of studies conducted to validate its antidengue activity was found to be inadequate. Hence, well-controlled clinical trials and contemporary pharmacological approaches including activity guided fractionation and elucidation of the mode of action are encouraged to establish the use of E. hirta for dengue.