Fractionation of rosmarinic acid rich extract from orthosiphon stamineus for enzymatic anti-diabetic activity

orthosiphon stamineus (o. stamineus) is one of the herbal plants containing high amount of rosmarinic acid. however, there is no standard guideline, specifically for rosmarinic acid rich extract from o. stamineus. therefore, this study was focused on the fractionation of rosmarinic acid from the o. stamineus crude extract using chromatographic methods, namely thin layer chromatography integrated with column chromatography (tlc-cc) and liquid-liquid extraction integrated with solid phase extraction (lle-spe). both fractionation methods were compared, and it was found that tlc-cc performed better than lle-spe to recover rosmarinic acid from the o. stamineus crude extract. the purity of the rosmarinic acid rich extract was 100% (fraction 8) which was greater than sub-fraction 1-3 (75%) prepared by lle-spe. tlc-cc increased the rosmarinic acid content from 3.6% w/w in crude extract to 100.0% w/w in the fraction 8, while lle-spe only increased the content of rosmarinic acid up to 75.0% w/w in the combined sub-fraction 1 to 3. the increase of rosmarinic acid content also simultaneously increased enzymatic anti-diabetic activities compared to the crude extract. the fraction of 100% rosmarinic acid from tlc-cc significantly (p < 0.05) inhibited the activity of a-amylase and a-glucosidase with ic50 values of 2.31 mg/ml and 0.34 mg/ml, respectively. the ic50 values were comparable to those results of standard drug, acarbose which showed 1.03 mg/ml and 1.66 mg/ml for a-amylase and a-glucosidase, respectively. kinetic studies revealed that the 100% rosmarinic acid fraction inhibited a-amylase competitively, but non-competitively for a-glucosidase inhibition. the introduction of rosmarinic acid as an inhibitor slow down the digestion rate of starch by a-amylases, and reduce the performance of a-glucosidase by decreasing its vmax value to 0.05 mm/min. understanding the kinetic information of the enzymatic reaction is important to predict in vivo metabolism of rosmarinic acid for drug design. in conclusion, high anti-diabetic property rosmarinic acid rich extract from o. stamineus can be obtained using column chromatography technology

Data from a pre-publication independent replication initiative examining ten moral judgement effects

We present the data from a crowdsourced project seeking to replicate findings in independent laboratories before (rather than after) they are published. In this Pre-Publication Independent Replication (PPIR) initiative, 25 research groups attempted to replicate 10 moral judgment effects from a single laboratory's research pipeline of unpublished findings. The 10 effects were investigated using online/lab surveys containing psychological manipulations (vignettes) followed by questionnaires. Results revealed a mix of reliable, unreliable, and culturally moderated findings. Unlike any previous replication project, this dataset includes the data from not only the replications but also from the original studies, creating a unique corpus that researchers can use to better understand reproducibility and irreproducibility in science

The pipeline project: Pre-publication independent replications of a single laboratory's research pipeline

This crowdsourced project introduces a collaborative approach to improving the reproducibility of scientific research, in which findings are replicated in qualified independent laboratories before (rather than after) they are published. Our goal is to establish a non-adversarial replication process with highly informative final results. To illustrate the Pre-Publication Independent Replication (PPIR) approach, 25 research groups conducted replications of all ten moral judgment effects which the last author and his collaborators had “in the pipeline” as of August 2014. Six findings replicated according to all replication criteria, one finding replicated but with a significantly smaller effect size than the original, one finding replicated consistently in the original culture but not outside of it, and two findings failed to find support. In total, 40% of the original findings failed at least one major replication criterion. Potential ways to implement and incentivize pre-publication independent replication on a large scale are discussed

The United States COVID-19 Forecast Hub dataset

Academic researchers, government agencies, industry groups, and individuals have produced forecasts at an unprecedented scale during the COVID-19 pandemic. To leverage these forecasts, the United States Centers for Disease Control and Prevention (CDC) partnered with an academic research lab at the University of Massachusetts Amherst to create the US COVID-19 Forecast Hub. Launched in April 2020, the Forecast Hub is a dataset with point and probabilistic forecasts of incident cases, incident hospitalizations, incident deaths, and cumulative deaths due to COVID-19 at county, state, and national, levels in the United States. Included forecasts represent a variety of modeling approaches, data sources, and assumptions regarding the spread of COVID-19. The goal of this dataset is to establish a standardized and comparable set of short-term forecasts from modeling teams. These data can be used to develop ensemble models, communicate forecasts to the public, create visualizations, compare models, and inform policies regarding COVID-19 mitigation. These open-source data are available via download from GitHub, through an online API, and through R packages

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Data from a pre-publication independent replication initiative examining ten moral judgement effects

We present the data from a crowdsourced project seeking to replicate findings in independent laboratories before (rather than after) they are published. In this Pre-Publication Independent Replication (PPIR) initiative, 25 research groups attempted to replicate 10 moral judgment effects from a single laboratory's research pipeline of unpublished findings. The 10 effects were investigated using online/lab surveys containing psychological manipulations (vignettes) followed by questionnaires. Results revealed a mix of reliable, unreliable, and culturally moderated findings. Unlike any previous replication project, this dataset includes the data from not only the replications but also from the original studies, creating a unique corpus that researchers can use to better understand reproducibility and irreproducibility in science.Link_to_subscribed_fulltex

The pipeline project: Pre-publication independent replications of a single laboratory's research pipeline

© 2015 The Authors This crowdsourced project introduces a collaborative approach to improving the reproducibility of scientific research, in which findings are replicated in qualified independent laboratories before (rather than after) they are published. Our goal is to establish a non-adversarial replication process with highly informative final results. To illustrate the Pre-Publication Independent Replication (PPIR) approach, 25 research groups conducted replications of all ten moral judgment effects which the last author and his collaborators had âin the pipelineâ as of August 2014. Six findings replicated according to all replication criteria, one finding replicated but with a significantly smaller effect size than the original, one finding replicated consistently in the original culture but not outside of it, and two findings failed to find support. In total, 40% of the original findings failed at least one major replication criterion. Potential ways to implement and incentivize pre-publication independent replication on a large scale are discussed.Link_to_subscribed_fulltex

Genetic stability of white Kelampayan (neolamarckia cadamba) plantlets derived from callus as explant using ISSR markers

Neolamarckia cadamba or generally known as white Kelampayan has been perceived as one of the potential fast growing tree species suitable for forest plantation establishment in Sarawak, Malaysia due to its multipurpose and high commercial values. Hence, micropropagation is a prevalent method to obtain sufficient amount of unifrom plants. In the present study, in vitro propagation of Kelampayan was attempted through multiple shoot regeneration from both callus and nodal segments cultured on Gamborg's B5 medium supplemented with various combinations of BAP, NAA and CWo 1.0 mg/L BAP was found to be the most effective for shoot regeneration from callus explants (9.09%) and produced multiple shoots (1.6) per explant. Repeated subculturing of newly fonned nodal parts after each harvest up to third passage, yielded higher number of shoots (1.97) per explant was obtained. Inter Simple Sequence Repeats (ISSR) marker was used to detennine the genetic stability of micropropagated and stock plants of Kelampayan. ISSR primers, (GTG)6 had generated an average of 6.5 clear bands, of which 36.11 % of the loci were polymorphic among 77 Kelampayan samples. All ISSR profiles from micropropagated plants were closely monomorphic and similar to the mother plants, while low variation was induced in the second subculture cycle. The genetic diversity, estimated by Shannon's index, was 0.1862, revealing a low level of genetic variation among them. The results indicated that genetic instability was obtained among the micropropagated Kelampayan plantlets when subcultured to second cycle

Anti-diabetic activity of rosmarinic acid rich fractions from orthosiphon stamineus

Background: There has been a great interest in the discovery of alternative medicines from medicinal herbs for type 2 diabetes, specifically screening for phytochemicals which are able to inhibit or delay glucose absorption. Introduction: The aim of this study was to evaluate the inhibition of crude extract and rosmarinic acid rich fractions from Orthosiphon stamineus on α-amylase and α-glucosidase activities. Methods: The plant crude extract was prepared by a reflux method using 70 %v/v ethanol, followed by fractionation using column chromatography to obtain rosmarinc acid rich fractions. Results: The crude extract and its rosmarinic acid rich fractions showed a dose dependent manner to inhibit the saccharide hydrolysing enzymes. Fr. A (100 % rosmarinic acid) was found to have comparable performance with standard rosmarinic acid as an inhibitor for both enzymes. Approximately, 62.50 mg/mL and 5 mg/mL of Fr. A were sufficient to achieve almost 100 % inhibition against α- amylase and α-glucosidase, respectively. Rosmarinic acid in Fr. A (IC50 0.34 mg/mL) was found to be 5 times more active than the anti-diabetic drug acarbose (IC50 1.66 mg/mL) in the inhibition of α- glucosidase. Fr. B with 50 % rosmarinic acid (IC50 1.48 mg/mL) had an inhibitory power comparable to that of acarbose. Kinetic studies revealed that Fr. A inhibited α-amylase competitively, but displayed non-competitive inhibition towards α-glucosidase. Rosmarinic acid had higher affinity towards α-glucosidase with lower Michaelis-Menten constant (Km), 1.42 mM. Conclusion: The findings suggest that rosmarinic acid rich fractions of O. stamineus could be a potential drug to regulate and manage type 2 diabetes mellitus