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The prevalence of inflammatory-mediated and oxidative stress-associated diseases is increasing worldwide, creating an increasing demand for novel sources of anti-inflammatory agents and antioxidants. This study was focused on determining the in vitro arachidonate 5-lipoxygenase (A5-LOX), xanthine oxidase (XO), hyaluronidase and oxidative burst inhibitory activities, and antioxidant properties of Ravi, Rawana, and Oshadha finger millet varieties using ethanolic and methanolic extracts. Among all extracts, the methanolic extract of Oshadha exhibited the highest A5-LOX (IC 50 value: 484.42  μ g/ml) and XO (IC 50 value: 764.34  μ g/ml) inhibitory activities. All extracts showed less than 50% hyaluronidase inhibitory activity at 1 mg/ml concentration. Methanolic extracts showed moderate inhibitory potential on reactive oxygen species (ROS) generated from whole blood phagocytes, with IC 50 values ranging between 26.9 and 27.7  μ g/ml, when compared to ibuprofen (IC 50 value: 11.18  μ g/ml). All extracts showed potent inhibition of ROS produced from polymorphonuclear neutrophils isolated from human blood when compared to ibuprofen (IC 50 value: 2.47  μ g/ml) and IC 50 values of methanolic and ethanolic extracts ranged from 0.29 to 0.47  μ g/ml and 1.35 to 1.70  μ g/ml, respectively. All extracts had significantly high amounts of phenolic compounds including flavonoids and the potential to scavenge 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic) acid (ABTS) cation, 2,2-diphenyl-1-picryl-hydrazyl (DPPH), and oxygen radicals. Besides, they were able to reduce metal ions and chelate metal ions terminating radical generating reactions. This is the first report of A5-LOX, XO, hyaluronidase, and oxidative burst inhibitory properties of any extract of any finger millet variety cultivated in Sri Lanka. The findings revealed the potential of using these finger millet extracts as natural sources of anti-inflammatory drug candidates. Additionally, the findings indicated that Ravi, Rawana, and Oshadha varieties are good sources of antioxidants. Therefore, consumption of these finger millet varieties on a regular basis may play an important role in the prevention and dietary management of oxidative stress-associated diseases., Competing Interests: There are no conflicts of interest to declare., (Copyright © 2021 Sooriya Arachchige Sachini Jayawardana et al.)

This study investigated the allelopathic activity of sixteen seaweed extracts using lettuce seed germination bioassay. The results of the preliminary investigation suggested that the methanol extracts of seven seaweeds demonstrated significant properties inhibitory to seed germination. In addition, chemical investigation of an active extract of the alleopathic Laurencia heteroclada Harvey led to the isolation of four known compounds as well as a new brominated nonaromatic isolaurene type sesquiterpene. The structural elucidation of pure compounds was carried out using spectroscopic methods and by comparison with literature. As seaweeds are highly abundant around Sri Lanka, they could be developed as an ecofriendly natural herbicide in their crude form.

Four new tropane alkaloids were isolated from the leaves of Erythroxylum moonii and identified as 3 alpha-isobutyryloxy-7 beta-hydroxynortropane (1), 3 alpha-hydroxy-7 beta-phenylacetoxynortropane (2), 3 alpha-cis-cinnamoyloxytropane (3), and 3 alpha-hydroxy-6 beta-(3'-hydroxy-2'-methyl-3'-phenylpropionyloxy)-7 beta-hydroxytropane (4). Other alkaloids isolated for the first time from E. moonii were 3 alpha-benzoyloxytropane, 3 alpha-phenylacetoxytropane, 3 alpha-trans-cinnamoyloxytropane, and 3 alpha-phenylacetoxy-6 beta,7 beta-dihydroxynortropane. The structures of compounds 1-4 were elucidated by spectroscopic methods.

Chemical investigation of the non-quaternary alkaloidal fraction of the aerial parts of Sarcococca zeylanica of the family Buxaceae furnished a steroidal alkaloid iso-N-formyl-5-en-chonemorphine, which has not been previously reported as a natural product. The structure of this alkaloid was established on the basis of spectroscopic evidence.