Science

6 readers
10 users here now

This magazine is dedicated to discussions on scientific discoveries, research, and theories across various fields, including physics, chemistry, biology, astronomy, and more. Whether you are a scientist, a science enthusiast, or simply curious about the world around us, this is the place for you. Here you can share your knowledge, ask questions, and engage in discussions on a wide range of scientific topics. From the latest breakthroughs to historical discoveries and ongoing research, this category covers a wide range of topics related to science.

founded 2 years ago
301
 
 

Hydroponics offers a viable solution for obtaining plant products that are rich in micronutrients and ultramicronutrients, such as selenium. Selenium plays a crucial role in strengthening the body's immune defense and acts as a potent antioxidant. Low levels of selenium have been associated with an increased risk of heart attacks, strokes, and cancer. Stevia rebaudiana Bertoni (SrB), a relatively new crop in plant cultivation, was the focus of the present study. SrB has numerous medicinal and prophylactic properties, and its leaves are rich in macro- and microelements, vitamins, and diterpene glycosides.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/37522778/

#science

302
 
 

Stevia is unaffected by stomach acid, pancreatic enzymes and the process of digestion. It travels essentially “untouched” by the digestive process until it reaches the large intestine. There it “reacts” with the gut flora. It is then absorbed in the colon and travels to the liver. It is then bound to glucuronic acid via the glucuronidation pathway and eventually excreted through the urine. The glucuronidation pathway is a major liver pathway that detoxifies drugs, pollutants, estrogen, and steroids, etc.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://www.portalsalud.com/cuales-son-los-peligros-de-la-stevia_13092860/

#science

303
 
 

Bladder cancer (BC) is a global health issue that lacks effective treatment strategies. Growing evidence suggests that various natural products possess anti-tumour effects. This study aims to identify a novel agent that can be used in the treatment of BC.
Collectively, our data suggest that stevioside can be a potential agent for the treatment of BC.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/35820501/

#science

304
 
 

Scientists in China have developed a method to produce spider silk from genetically modified silkworms, offering a strong, sustainable alternative to synthetic fibers with applications in various industries. Researchers have synthesized spider silk from genetically modified silkworms, producing f

305
 
 

To whom it may concern.

306
 
 

Gustul ceaiului de kombucha diferă de la un producător la altul în funcție de metodele de preparare. Tocmai de aceea vă invităm să testați cele 8 sortimente iKombucha. După o experiență de peste 7 ani în producerea de kombucha, am adăugat la rețetele noastre stevia ca și îndulcitor, pentru ca produsul final să nu fie prea acru la gust pentru majoritatea clienților. Am dezvoltat 8 sortimente cu diferite arome, care să acopere înr-o anumită măsură gustul de ferment și să ofere gusturi plăcute.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://healthfully.com/stevia-and-cancer-5918164.html

#science

307
 
 

Stevioside is a diterpene glycoside found in the leaf of Stevia rebaudiana, a traditional oriental medicinal herb, which has been shown to have various biological and ethno-medicinal activities including antitumor activity. In this study, we investigated the effects of stevioside on the cytotoxicity, induction of apoptosis, and the putative pathways of its action in human breast cancer cells (MCF-7). For the analysis of apoptotic pathway, measurement of reactive oxygen species (ROS) and assessment of mitochondrial transmembrane potential (MTP) were achieved. We showed that stevioside was a potent inducer of apoptosis and it conveyed the apoptotic signal via intracellular ROS generation; thereby inducing change in MTP and induction of mitochondrial mediated apoptotic pathway. Taken together, our data indicated that stevioside induces the ROS-mediated mitochondrial permeability transition and results in the increased expression of apoptotic proteins such as Bax, Bcl-2 and Caspase-9. Effect of stevioside on stress-related transcription factors like NF-E2-related factor-2 opens up a new vista for further studies. This is the first report on the mechanism of the antibreast cancer (in vitro) activity of stevioside.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/23061910/

#science

308
 
 

A β-galactosidase from Kluyveromyces lactis was found to specifically catalyze hydrolysis of the glycosyl ester linkage of stevioside to yield steviolbioside, a rare sweetener that also exists in Stevia rebaudiana leaves. In a packed bed reactor, a reaction coupling separation was realized and a production yield of steviolbioside reached 90% in 6 h. The hydrolysis product steviolbioside presented higher cytoxicity on human normal cells (hepatocytes cell L02 and intestinal epithelial cell T84) than stevioside did. Comparing to the typical chemotherapy agent, 5-fluorouracil (5-FU), steviolbioside presents much lower cytotoxicity on all assayed human normal cells; it presented notable inhibition on human hepatocarcinoma cell Hep3B, human breast cancer cell MDA-MB-231 and human pancreatic cancer cell BxPC-3. The remarkable inhibition on MDA-MB-231 cells makes steviolbioside a potential remedy for human breast cancer, when steviolbioside is served as a natural sweetener.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/26593477/

#science

309
 
 

Regarding nutritional benefits, the available studies, while numerous, do not provide proof that the consumption of artificial sweeteners as sugar substitutes is beneficial in terms of weight management, blood glucose regulation in diabetic subjects or the incidence of type 2 diabetes. Regarding nutritional risks (incidence of type 2 diabetes, habituation to sweetness in adults, cancers, etc.), it is not possible based on the available data to establish a link between the occurrence of these risks and the consumption of artificial sweeteners. However, some studies underline the need to improve knowledge of the links between intense sweeteners consumption and certain risks.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/26430511/

#science

310
 
 

Researchers now hope to use the environmental engineering success to combat climate change.

311
312
 
 

Depression is not a gentle opponent, yet, forward-thinking studies and fresh advancements in technology have shed light on the way to triumph over this disease. In a new research study, there’s some positive news for the millions grappling with treatment-resistant depression (TRD). DBS (Deep Brain Stimulation) is beginning to show remarkable progress which seems to offer a ray of hope for the people who are suffering from debilitating Tourette’s syndrome. DBS, still an early stage trial, is a pr

313
 
 

The essential oil extracted by hydrodistillation from the flowering twigs of Stevia rebaudiana Bertoni (Asteraceae) was fractioned by chromatography. Forty-three constituents were characterized with the help of GC, GC-MS and other spectroscopic techniques. The essential oil was found to be a complex mixture of mono- and sesqui-terpenes. The cytotoxicity of the essential oil and its fractions was evaluated by sulforhodamine B (SRB) based assay against two cancer cell types viz. C-6 (rat glioma cells) and CHOK1 (Chinese hamster ovary cells). The essential oil and its fractions showed promising cytotoxicity against both cell lines. The highest activity (95.6+/-0.6%) was show by the essential oil on the C-6 cell line at a concentration of 400 microg/mL, which was comparable with that of the standard drug vinblastin.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/25026731/

#science

314
 
 

Stevia, a zero-calorie sugar substitute, is recognized as safe by the Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA). In vitro and in vivo studies showed that stevia has antiglycemic action and antioxidant effects in adipose tissue and the vascular wall, reduces blood pressure levels and hepatic steatosis, stabilizes the atherosclerotic plaque, and ameliorates liver and kidney damage. The metabolism of steviol glycosides is dependent upon gut microbiota, which breaks down glycosides into steviol that can be absorbed by the host. In this review, we elucidated the effects of stevia's consumption on the host's gut microbiota. Due to the lack of randomized clinical trials in humans, we included in vitro using certain microbial strains and in vivo in laboratory animal studies. Results indicated that stevia consumption has a potential benefit on the microbiome's alpha diversity. Alterations in the colonic microenvironment may depend on the amount and frequency of stevia intake, as well as on the simultaneous consumption of other dietary components. The anti-inflammatory properties of stevioside were confirmed in vitro by decreasing TNF-α, IL-1β, IL-6 synthesis and inhibiting of NF-κB transcription factor, and in vivo by inhibiting NF-κB and MAPK in laboratory animals.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/35456796/

#science

315
 
 

Steviol glycosides (SGs) in Stevia (Stevia rebaudiana Bertoni) leaves are important due to their high sweetness and low calorific value. The yield of SGs is dependent on fertilization regimes, but the relationship between nitrogen (N) administration and SGs synthesis is still unclear. In this study, we investigate the effects of N rates on SGs production through hydroponic and plot experiments. The SGs yield was not significantly changed by N fertilization, but leaf SGs concentrations were significantly reduced due to the "dilution effect". Additionally, N addition decreased leaf carbon (C)/N ratio and soluble sugar concentration, accompanied with the inhibited phosphoenolpyruvate carboxylase and L-phenylalanine ammonia_lyase activities. A significant positive correlation between leaf SGs concentrations, C/N ratio and soluble sugar concentration was observed. Overall, we suggest that N-driven Stevia growth negatively affects SGs concentrations. The leaf C/N ratio and soluble sugar changes indicated the occurrence of metabolic reprogramming.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/31195254/

#science

316
 
 

Plant growth and secondary metabolism are commonly regulated by external cues such as light, temperature and water availability. In this study, the influences of low and high temperatures, dehydration, photoperiods, and different growing stages on the changes of steviol glycosides (SGs) contents and transcription levels of fifteen genes involved in SGs biosynthesis of Stevia rebaudiana Bertoni were examined using HPLC and RT-PCR. The observations showed that the transcript levels of all the fifteen genes were maximum under 25 °C treatment, and the transcription of SrDXS, SrDXR, SrMCT, SrCMK, SrMDS, SrHDS, SrHDR, SrIDI, SrGGDPS, SrCPPS1, SrUGT85C2 and SrUGT76G1 were restrained both in low temperature (15 °C) and high temperature (35 °C). Most genes in SGs biosynthesis pathway exhibited down-regulation in dehydration. To elucidate the effect of photoperiods, the plants were treated by different simulated photoperiods (8 L/16 D, 1 0L/14 D, 14 L/10 D and 16 L/8 D), but no significant transcription changes were observed. In the study of growing stages, there were evident changes of SGs contents, and the transcript levels of all the fifteen genes were minimal in fast growing period, and exhibited evident increase both in flower-bud appearing stage and flowering stage. The obtained results strongly suggest that the effect of environmental cues on steviol glycosides contents and transcription of corresponding biosynthetic genes in S. rebaudiana is significant. It is worth to study deeply.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/25500454/

#science

317
 
 

More than 60 naturally occurring steviol glycosides in the Stevia rebaudiana Bertoni plant share a similar molecular structure with an aglycone steviol backbone conjugated with β- and α-glycosidic bonds to different sugar moieties. These glycosides are naturally produced in different quantities within the stevia leaf. Certain minor glycosides with superior sensory attributes, such as Reb D and Reb M, are found less than 0.1% in traditional stevia leaves. New technologies can now produce better tasting steviol glycosides by using enzymatic conversion of stevioside and Reb A, which are abundant in stevia leaf. Several regulatory authorities recently evaluated steviol glycosides produced by enzymatic conversion of stevia leaf extract and approved them safe for human consumption. Steviol glycosides undergo microbial hydrolysis in the colon to generate steviol, which is absorbed and metabolized into steviol glucuronide, and excreted primarily via human's urine. Previous studies have shown the hydrolysis of highly purified individual steviol glycosides extracted from stevia leaf are converted to steviol in the presence of colonic microbiota of adults. Since colonic microbiota of children may be different from adults, this study investigates the metabolic fate in the colonic microbiota of adults and children of the minor steviol glycosides produced by extraction and enzymatic conversion of major steviol glycosides from stevia leaf. Several in vitro incubation tests were conducted in human fecal homogenates collected from adult and pediatric populations with steviol glycoside test samples comprised of a complex stevia leaf extract, a blend of minor glycosides isolated from stevia extract and two mixtures of steviol glycosides produced by enzymatic conversion of Reb A to larger molecules by attaching glucose units via β- or α-glycosidic bonds. Results from these studies clearly demonstrate steviol glycosides produced by extraction from stevia leaf, or enzymatic conversion of stevia leaf extract, share the same metabolic fate in the human gut microbiota from adults and children. Considering a common metabolite structure and a shared metabolic fate in all ages, safety data for individual steviol glycosides can be used to support safety of all steviol glycosides produced by extraction and enzymatic conversion of stevia leaf extract.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/32745585/

#science

318
 
 

Stevia rebaudiana Bertoni is a valuable plant whose products are increasingly used in medicine, pharmacy and the food industry. This necessitates the use of biotechnological approaches for its mass propagation. Establishing optimal conditions for in vitro cultivation is essential for obtaining high biomass and secondary metabolites production. A large number of articles considering the role of plant growth regulators and other additives in the culture medium in the growth and development of Stevia are available in the literature. However, there are no summarized data about the use of nanoparticles in Stevia tissue cultures. Therefore, this review also includes the research conducted so far on the effect of nanoparticles on Stevia micropropagation. Furthermore, the influence of different elicitors on secondary metabolite production and antioxidant activity of in vitro-cultivated Stevia plants have been discussed. By referring to the collected literature, we concluded that biotechnological approaches applied to S. rebaudiana cultivation might improve the agronomic traits of plants and steviol glycosides production.
#Stevia #kombucha #ikombucha_ro #ikombucha
https://pubmed.ncbi.nlm.nih.gov/36616282/

#science

319
 
 

Scientists have created a power generator that uses atmospheric humidity and polyoxometalates to produce continuous electricity, offering a sustainable way to utilize low-value energy.

320
 
 

Lung cancer is the leading cause of cancer-related deaths in the United States. Some tumors are extremely small and hide deep within lung tissue, making it difficult for surgeons to reach them. To address this challenge, UNC –Chapel Hill and Vanderbilt University researchers have been working on an extremely bendy but sturdy robot capable of traversing lung tissue.

321
 
 

Researchers publicly call out theory that they say is not well supported by science, but that gets undue attention.

A letter, signed by 124 scholars and posted online last week1, has caused an uproar in the consciousness research community. It claims that a prominent theory describing what makes someone or something conscious — called the integrated information theory (IIT) — should be labelled “pseudoscience”. Since its publication on 15 September in the preprint repository PsyArXiv, the letter has some researchers arguing over the label and others worried it will increase polarization in a field that has grappled with issues of credibility in the past.

322
 
 

Ancient timber preserved in a riverbed suggests humans were building wooden structures 500,000 years ago.

323
 
 

For a phenomenon that is so deeply engrained in the public consciousness, the scientific evidence regarding what has been called "beer goggles" is surprisingly inconsistent. The term refers to finding people more attractive after drinking alcohol, and there is a wealth of scientific evidence both for and against its existence.

324
 
 

Paleontologists at University College Cork (UCC) in Ireland have discovered X-ray evidence of proteins in fossil feathers that sheds new light on feather evolution.

325
 
 

this is driving me pretty mad, i've got hygrometers, digital and analog all reading wildly different percentages, and would like to calibrate them, read up on the salt test, where you take salt make it damp stick it in a plastic bag and after +8 hrs the internal humidity of the bag should be exactly 75%. for anyone that's familiar with calibrating hygrometers, should 2 TBSP table salt plus 1/2 TBSP water in a small monkey dish, in a gallon bag work? or is it too much water for the salt, too big of a bag, too much or too little time. did the test overnight on 4 different hygrometers for 12 hours, took them out of the bag, and now after 30 minutes to equalize to room temp, are not only once again wildly off, but the lowest is reading what I would imagine to be 10 percentage points of how humid the room "feels". maddening. thanks.

view more: ‹ prev next ›