Allelopathic Impacts of an Agroforestry Tree Species (Streblus asper Lour.) on Seed Germination and Seedling Growth of Chickpea

Background: Agroforestry might be a better strategy for sustainable land use and crop production. Allelopathic effect of Streblus asper Lour. (Moraceae) an agroforestry tree species was documented on chickpea (Cicer arietinum L.) seed germination and seedling growth. Methods: The present study was conducted to evaluate the allelopathic potentialities of different concentrations (0.125%, 0.25%, 0.5%, 1.0%, 2.5% and 5%) of aqueous leaf extracts of S. asper on seed germination and seedling growth in laboratory based experiments. The allelopathic potentialities were studied based on seed germination, germination rate, root length, shoot length, biomass, seed vigor index etc. Result: The inhibitory effect was more pronounced with the increasing concentrations of aqueous extracts. 5% aqueous leaf extracts showed a maximum inhibitory effect on seed germination, root length, shoot length, dry weight of root and shoot as compared to control. Based on the allelopathic index, concentrations of 5% aqueous extract showed a strong inhibitory effect. Aqueous leaf extracts contain water-soluble allelochemicals which affect the seed germination and seedling growth. The inhibitory allelopathic effect can be taken as serious consideration before plantation of chickpea in an association of this tree species because of its inhibitory effect on seed germination and early stages of development.

Interaction of (+)-Strebloside and Its Derivatives with Na+/K+-ATPase and Other Targets

Docking profiles for (+)-strebloside, a cytotoxic cardiac glycoside identified from Streblus asper, and some of its derivatives and Na+/K+-ATPase have been investigated. In addition, binding between (+)-strebloside and its aglycone, strophanthidin, and several of their other molecular targets, including FIH-1, HDAC, KEAP1 and MDM2 (negative regulators of Nrf2 and p53, respectively), NF-κB, and PI3K and Akt1, have been inspected and compared with those for digoxin and its aglycone, digoxigenin. The results showed that (+)-strebloside, digoxin, and their aglycones bind to KEAP1 and MDM2, while (+)-strebloside, strophanthidin, and digoxigenin dock to the active pocket of PI3K, and (+)-strebloside and digoxin interact with FIH-1. Thus, these cardiac glycosides could directly target HIF-1, Nrf2, and p53 protein–protein interactions, Na+/K+-ATPase, and PI3K to mediate their antitumor activity. Overall, (+)-strebloside seems more promising than digoxin for the development of potential anticancer agents.

Physical properties of handsheets derived from Coi (Streblus asper Lour.) pulp fiber as papermaking material traced from ancient times

There have been recent attempts to revive the traditional production of handmade paper from the bark of the Coi (Streblus asper Lour.) tree in Thailand. A sheet sample of Coi handmade paper, made from the traditional production, was collected and examined microscopically for the first time. Film-like material and cubic calcium particles were found on the sheet sample surface, which is consistent with the results of the authors’ previous research. Meanwhile, handsheets derived from Coi pulp fiber, freshly made in the laboratory, demonstrated a low air permeance and brightness with high opacity due to the film-like material and cubic calcium particles. With a high felting power of Coi pulp fiber coupled with a possible strengthening role of the film-like material, both the beaten and unbeaten fibers were used to form handsheets with high strength. Some potential aspects of Coi pulp fiber suitable for creating a unique Thai banknote paper have been demonstrated, for which further studies are suggested.

Streblus asper Lour. exerts MAPK and SKN-1 mediated anti-aging, anti-photoaging activities and imparts neuroprotection by ameliorating Aβ in Caenorhabditis elegans

BACKGROUND: Streblus asper Lour., has been reported to have anti-aging and neuroprotective efficacies in vitro. OBJECTIVE: To analyze the anti-aging, anti-photoaging and neuroprotective efficacies of S. asper in Caenorhabditis elegans. METHODS: C. elegans (wild type and gene specific mutants) were treated with S. asper extract and analyzed for lifespan and other health benefits through physiological assays, fluorescence microscopy, qPCR and Western blot. RESULTS: The plant extract was found to increase the lifespan, reduce the accumulation of lipofuscin and modulate the expression of candidate genes. It could extend the lifespan of both daf-16 and daf-2 mutants whereas the pmk-1 mutant showed no effect. The activation of skn-1 was observed in skn-1::GFP transgenic strain and in qPCR expression. Further, the extract can extend the lifespan of UV-A exposed nematodes along with reducing ROS levels. Additionally, the extract also extends lifespan and reduces paralysis in Aβ transgenic strain, apart from reducing Aβ expression. CONCLUSIONS: S. asper was able to extend the lifespan and healthspan of C. elegans which was independent of DAF-16 pathway but dependent on SKN-1 and MAPK which could play a vital role in eliciting the anti-aging, anti-photoaging and neuroprotective effects, as the extract could impart oxidative stress resistance and neuroprotection.

INVESTIGATION OF ANALGESIC, ANTIOXIDANT, AND CYTOTOXIC PROPERTIES OF THE ETHANOLIC EXTRACT OF STREBLUS ASPER (ROOTS)

Objective: This study evaluated the analgesic, antioxidant, and cytotoxic effects of ethanolic extract of Streblus asper roots. Methods: Analgesic activities were carried out using paw licking and writhing tests. The extract was used at doses of 250 and 500 mg/kg per orally in Swiss albino mice of body weight 25–30 g. Antioxidant properties were investigated using 1, 1-diphenyl-1-picrylhydrazyl free-radical scavenging assay, total phenol content, total flavonoid content as well as reducing power capacity. The cytotoxic activity was determined by the Brine Shrimp lethality bioassay. Results: The ethanolic extract of S. asper roots showed a significant effect in the formalin test (p<0.01). They also exhibit the highest analgesia (p<0.01) in the acetic acid-induced writhing model as well. The extract possessed antioxidant effects in all the models. It possessed a good cytotoxic activity. Conclusion: The results suggested that S. asper root extract has a suitable analgesic, antioxidant effect as well as significant cytotoxic potential.

Effect of Streblus asper Leaf Extract on Scopolamine-Induced Memory Deficits in Zebrafish: The Model of Alzheimer’s Disease

Streblus asper (SA) is well known as a folk medicinal plant in Asian countries. The effect of SA extract on preventing memory impairment in zebrafish induced by scopolamine was investigated. Male zebrafish, Danio rerio, were divided into 6 groups including the control, scopolamine 200 μM (SCO), scopolamine plus rivastigmine 1.5 mg/kg (RV + SCO), and scopolamine plus SA extract at doses of 200, 400, and 800 mg/kg (SA200 + SCO, S400 + SCO, and SA800 + SCO), respectively. Spatial memory was evaluated by the colour-biased appetite conditioning T-maze test, while fear memory was measured by the inhibitory avoidance test. In the spatial memory test, results showed that the RV + SCO group had the best time spent ratio in the T-maze, followed by SA800 + SCO, SA400 + SCO, SA200 + SCO, control, and SCO group, respectively, but with no statistical significance. For the fear memory test, zebrafish that received SA at doses of 200, 400, and 800 mg/kg had significantly increased latency time as 21.75 ± 4.59, 23.75 ± 13.01, and 18.20 ± 18.84 min, respectively, when compared to the SCO group (9.80 ± 10.45 min). These results suggested that SA extract attenuated memory impairment in an inhibitory avoidance test related to fear memory. Our findings can be useful for further research to develop SA extract as a health product to ameliorate the symptoms of Alzheimer’s disease.