Talk:Chitosan

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Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 17:34, 16 January 2022 (UTC)

Product Claims

Is it just me, or does the section cited by reference 17 reads like an advertisement? The only reference given is a whitepaper from the manufacturer's website. Removing it for now, until it can be rewritten with more encyclopedic language. --Revaaron (talk) 16:36, 3 July 2009 (UTC)

The text was reinserted and cited with correct reference article. --Agrihouse (talk) 20:46, 13 July 2009 (UTC)

This entry reads less as a wikipedia entry, and more as a ad for the industry. —Preceding unsigned comment added by 132.79.9.15 (talk) 20:23, 21 April 2011 (UTC)

Agricultural Uses of Chitosan

Elicitation of Natural Defenses Response in Plants: AgriHouse Inc (Denver, Colorado) has completed over 20 years of agricultural research on chitosan in conjunction with Dr. James Linden, Professor Emeritus, Departments of Chemical and Biological Engineering and of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado and Dr. Ken Knutson, Professor Emeritus, Plant Pathologist, Director Seed Potato Certification, Colorado State University, Fort Collins, Colorado. Richard Stoner, Founder and Pres., is a co-inventor, hold patents and pending patents on the defense elicitation of plants using chitin / chitosan.

DuPont-ConAgra Venture (DCV), Wilmington DE, was granted patents for spraying chitosan on the leaves of plants to elicit natural defense responses by the plants against pathogens and pesticides. AgriHouse has been assigned the DCV patents in 2009.

The EPA and USDA regulate the use of Chitosan on agricultural crops. Chitosan is known to elicit natural disease responses and boost growth in plant and trees. see YouTube video [1]

In September of 2008 AgriHouse Inc was granted EPA registration (EPA reg. no. 83729-1) for YEA!® Yield Enhancing Agent, containing an active ingredient of 0.25% chitosan and 99.75% inert materials.trytuiuiuiuiui The following articles have been written by inventors:

Linden, J., Stoner, R., Knutson, K. Gardner-Hughes, C. “Organic Disease Control Elicitors”. Agro Food Industry Hi-Te (p12-15 Oct 2000)

Linden, J.C. and Stoner R.J. 2005. Proprietary Elicitor Amends Potato Emergence and Yields. Potato Grower. April. pp. 34-35.

Linden, J.C. and Stoner, R.J. 2005. Proprietary Elicitor Affects Seed Germination and Delays Fruit Senescence. Journal of Food, Agriculture & Environment (in press).

Stoner, R., Progressive Plant Growing Has Business Blooming, Environmental and Agricultural Resources NASA Spinoff 2006, pp68-71.

Linden, J.C. and Stoner, R.J. 2007. Pre-harvest application of proprietary elicitor delays fruit senescence. A. Ramina et al. (eds.). Advances in Plant Ethylene Research: Proceedings of the 7th International Symposium on the Plant Hormone Ethylene. pp 301-302. Springer: Dordrecht, The Netherlands.

These articles and field trials with chitosan elicitors can found at http://www.yeacrops.com

--71.208.51.86 (talk) 18:27, 10 April 2009 (UTC)

--71.208.51.86 (talk) 17:19, 10 April 2009 (UTC)

Chitosan has been reported in the New York Times, Oct 3. 2007 to be a stressor that can illicit an increase in the devensive response of some plants. Namely, the production of antioxidants and 'aroma compounds' related to flavor. They site a study of basil stressed by being soaked in the compound by Clemson University professors Dr. Hyn-Jin Kim and Feng Chen.

NYT October 3, 3007 Organic, and Tastier: The Rat's Nose Knows [2] RRphys 15:10, 3 October 2007 (UTC)

Weight loss

Personal experiance? It does remove the fat, but you have to drink lots of water. Eathing grasy foods while you take it is BAD. Be prepared for a long stay in the bathroom. If I find articles on the side effects I'll put a link in. It works, it just anit no magic bullet. Lyta79 (talk) 18:02, 19 December 2009 (UTC)

Chitosan really help to lose weight to some, by diminishing appetite. It probably doesn't work the way it is advertised, but it's "working". Based on my personnal experience and "feelings", it works by binding to heavy metals (mercury, lead).

While a possible reduction in fat absorption might in some cases cause someone to subtly feel a bit different, that is by no means a determining factor. Secondly, one rarely consumes any heavy metals in one's diet, but are you saying that chitosan is a chelating/detoxifying agent? I haven't come across that claim elsewhere. --Amit 16:02, 19 July 2006 (UTC)

Well I have, Mercola website cites tree studies showing Chitosan removes mercury from the gut(like Chlorella). I would like to see more information on that, does anyone have other sources(Tradingbr 12:41, 14 October 2006 (UTC))

@Amit: Yes, I heard before that chitosan is used as detoxifying agent. It is used in water filters, to filter out certain heavy metals. effeietsanders 07:43, 16 October 2006 (UTC)

Hi, could you provide a link for that?(Tradingbr 12:49, 17 October 2006 (UTC))

Hmmm, I made a report about this stuff some time ago. It should be somewhere in one of these links I guess...

Whether or not your "feelings" lead you to believe that chitosan suppresses appetite by way of "binding to heavy metals" is immaterial. Your own subjective "feelings" on the matter don't provide any sort of empirical support for the idea that chitosan promotes weight loss, acts as an appetite suppressant, or binds to heavy metals. Chitosan may do all or some of these, but whether or not you believe it to be so isn't a valid basis for providing claims to that effect in an encyclopedia. References to peer reviewed research would. --Revaaron (talk) 16:36, 3 July 2009 (UTC)

• [1] http://www.vupp.cz/czvupp/publik/04poster/04Chitosan2003.pdf
• [2] http://www.scielo.br/scielo.php?pid=S1517-83822001000100005&script=sci arttext&tlng=en
• [3] http://ift.confex.com/ift/2002/techprogram/paper_12669.htm
• [4] http://www.france-chitine.com/
• [5] http://www.ttz-bremerhaven.de/english/bilb/chitofood/workplan.html
• [6] http://www.ft.vslib.cz/indoczech-conference/conference_proceedings/fulltext/Turkey 05.pdf
• [7] http://etd.lsu.edu/docs/available/etd-11102004-134343/
• [8] http://www.ualberta.ca/�vmitchel/
• [9] http://www.sigmaaldrich.com/catalog/search/SearchResultsPage
• [10] http://dalwoo.com/chitosan/preparation.htm

125.163.100.242 11:41, 10 August 2007 (UTC)*[11] http://biotech.co.id At least this website tells about it: [3]. I know it is not much, but the scientist who helped me with this project told it was reasonable, and it had probably something to do with the helix-shape it could be trapped in. effeietsanders 11:24, 30 October 2006 (UTC)

Clarifying agent

Chitosan is often used in conjunction with Bentonite as a clarifying agent in wine making to remove unwanted cloudiness and hazes in the finished product. Kitsune818 13:44, 30 May 2006 (UTC)

Unreferenced claim

Chiosan will also increase the bioavailability of morphine.

Bioavailability of Morphine: Oral: ~30% Insufflated: 10-20%

Here's the VERY interesting part: Chitosan [a linear polysaccharide that helps absorb drugs better] has been shown to increase nasal bioavailability of morphine from around 10-20% to over 60%

Going from 20% TOPS, to over 60% for insufflation methods of ingestion.

here are the references (i wrote about in my diploma thesis):

Illum, L., P. Watts, et al. (2002). "Intranasal delivery of morphine." Journal of Pharmacology and Experimental Therapeutics 301(1): 391-400.

Pavis, H., A. Wilcock, et al. (2002). "Pilot study of nasal morphine-chitosan for the relief of breakthrough pain in patients with cancer." Journal of Pain and Symptom Management 24(6): 598-602.

best regards 130.208.188.119 01:16, 4 June 2007 (UTC)

History of chitosan

If anyone can provide information on history it wold be interesting. E.g.:

• when first isolated, when named, ...by whom

      The earliest reference I can find to Chitosan was the isolation from fungal cell walls by Henri Braconnot in 1811 who named it fungine. It was later isolated from the exoskeleton of crustacea by C. Odier in 1823 who named it chitin. Tom Kean 23:25, 8 November 2010 (UTC)  —Preceding unsigned comment added by Keantom (talk • contribs)  

• when first used for specific applictions (...by whom)

—DIV (128.250.80.15 (talk) 07:33, 28 December 2007 (UTC))

There is a reference to chitin in 1892

Amyloid substance. Krawkow, N. P. Centr. Med., Wiss. (1892), 145-48. From: J. Chem. Soc., Abstr. 64, I, 288 1893

and to both chitin and chitosan in 1894

Chitin and cellulose. Hoppe-Seyler, F. Berichte der Deutschen Chemischen Gesellschaft (1894), 27 3329-31. From: J. Chem. Soc., Abstr. 68, I, 166-7 1895

Source: SciFinder Scholar 2006, ACS
I am certain these are not the earliest references. —DIV (128.250.80.15 (talk) 07:43, 28 December 2007 (UTC))

Clarify

If you can, please clarify whether chitosan is ever found in nature, or if ALL chitosan is derived from chitin. ike9898 (talk) 15:15, 25 August 2010 (UTC)

The definition of chitosan is controversial, but commonly defined as chitin with a DDA>50%. While that doesn't mean solubility per se, it is the most accepted definition. Under that definition, chitosan has been found in several species (fungi mainly) and the genes for deacetylation has been also characterized. However, to my knowledge, no specie produce ONLY chitosan, but both chitin and chitosan.

--Jgfermart (talk) 15:23, 2 June 2014 (UTC)

SAFETY

Maybe it can be claimed that chitosan doesn't bien important minerales, but it can't be claimed that "there is no proof of any adverse events, in particular regarding nutrient absorption, in humans" as long as it binds fat, and there are vitamins that ARE fat like vitamin E or vitamin D — Preceding unsigned comment added by 193.144.79.183 (talk) 13:49, 24 January 2012 (UTC)

Infomercial?

As a biologist who's looking for factual information about chitosan, this article reads in a very unbalanced way. In fact, it reads almost like an advertisement for a product from two people whose patent applications are cited repeatedly in this article. It would be a very good idea for a biologist or biochemist with specialist knowledge of this area to edit the page thoroughly and for claims of biological and agricultural activity to be presented in a more balanced manner. OldSpot61 (talk) 10:18, 5 December 2012 (UTC)

Perhaps apply at the Task Force for someone like that to take a look? Guess you mean Linden/Stoner; have merged 2 refs (2007). To be fair, there are over 40 refs to other people's papers; perhaps L&S are just good active researchers in this field. Does need an expert to assess. Chiswick Chap (talk) 10:47, 5 December 2012 (UTC)

Harvard myopic? --> Manufacture with chitosan by Zefr: Erroneous explanation of the technology and blatantly false claims. 4 times reverted corrections

I am having an edit war with an unregistered user who has adopted a Harvard myopic that all credit for "bioinspired" industrial uses of chitosan is awarded to a Harvard lab. The editor uses only Harvard references while there is abundant precedence in the literature for prior art, publications or applications. The section below has been reverted twice, so consider further reversals of what I intended to be a WP:NPOV version with references of varied origin as edit warring,WP:3RR. A fair-minded view, which I have invited to be discussed on this Talk page, would be for the Harvard editor to explain reasons why that bias is valid. --Zefr (talk) 00:57, 26 May 2014 (UTC)

---Answer --- Zefr your explanation and understanding of the manufacture with chitosan are incomplete and with several major mistakes. For that reason I have reverted your edition several times. The technology to manufacture consumables with pure chitosan was disclosed a few weeks ago, that the reason to include only reference to that work. Below I point some of your sentences and their problem. I recommend you to get more information on the subject or let people with knowledge of the field to edit this section:

Please register or identify your affiliation so we are assured your edits are WP:NPOV and not WP:COI. Also please sign with your signature and timestamp. I suspect you are the author himself or someone in the same lab group, giving a strong bias toward the Harvard lab as having solely established this concept despite evidence in the literature that these concepts have been building toward chitosan consumable products for many years based on the work of others. Citing that literature evidence is part of the purpose for the Article; see WP:CON. --Zefr (talk) 17:12, 26 May 2014 (UTC)

Following definition of matrix formation in bioinspired materials,[31][32] ---> This sentence doesn't makes sense at all. "Bioinspired materials" and "matrix formation" are unrelated concepts.

a concept inspired by natural shrimp or insect cuticles.[33][34] --> False claim, the reproduction of the insect cuticle is a previous work of the authors cited in my original explanation (who are there because, being the primary group working in this subject, are relevant for the topic). The manufacture with chitosan is a different piece of work than the formation of the insect cuticle mimic (aka Shrilk). Please, refer to the published scientific communications.

It seems unrealistic to assign all responsibility for development of chitosan consumables and even to Shrilk as only a Harvard discovery, given the work of the Houston group.[4] --Zefr (talk) 17:12, 26 May 2014 (UTC)

Pigmented chitosan objects can be recycled,[37] with the option of reintroducing or discarding the dye at each recycling step ---> false claim, authors separate dye and polymer, but to my knowledge they have never claim the reintroduction of the dye.

A different outcome from conventional plastics manufacturing where colorant is covalently bonded to the structure and not reused. --> False claim, colorant in conventional plastics is covalently bonded to the polymer, and therefore it can be separated from the polymer. Therefore, it is always reused with the polymer.

Fair enough, but as a courtesy to my or any editor's work to edit the text and find supportive references possibly helpful to others, it's beneficial to edit the revision rather than reverting it wholescale. --Zefr (talk) 17:12, 26 May 2014 (UTC)

Additionally, unlike other biomaterials, chitosan-based bioplastic does not contaminate soils or other resources used by humans ---> While this could be true, this is an unproven claim. The authors claim. They claim the sources of chitin do not compete with basic human needs.

There seems abundant evidence that chitosan is biodegradable, non-toxic and safe,[5] indicating my statement was general and reasonable. --Zefr (talk) 17:12, 26 May 2014 (UTC)

Reproducing a natural design using chitosan favors large-scale technological and product applications, and further encourages development of shrilk, a chitosan material that replicates insect cuticle and a fibroin protein from silk. The method has potential to engineer human organs or tissues using three-dimensional bioprinting. ---> Both claims are false. There is also a section of "biomedical uses". It doesn't correspond to this section to cover medical uses.

Please register and sign your comments. This statement is easily edited rather than being wholesale reverted. I will be editing this section again. --Zefr (talk) 17:12, 26 May 2014 (UTC)

--- Hi Zerf, I am not the author but I am a member of Harvard University and I know this research very well because my group focus in very similar stuff. I am not going to register because I just started collaborating with the Wikipedia thinking that I would have something to offer. However until now my experience is that I am wasting a lot of time trying to explain basic concepts of my field of expertise. I am very sure this part of the article will be enhanced as soon as this research is continued by the original team or others, but right now the one and only team able to produce large 3D objects with pure chitosan is this one.

The article of Huston group is a result already included in the original Shrilk study. Also I believe you missed the two main point of that study. First point is that the resulting mechanical properties of the fibroin chitosan blend are worse that the pure chitosan. They present a method to enhance fibroin properties. Second, the article of Shrilk was groundbreaking at that point (please, read associated literature to that result from National Geographic, Scientific America, The guardian, Science… while knowing how to use google doesn’t make us experts in every field, a google serach will give thousands of reviews of that work) because it didn’t mixed the two components of the insect cuticle, but it reproduced the hierarchical design of the insect cuticle with the same components. The result of that process was a material twice stronger that the stronger component.

That result caused the impact it caused because other groups have used natural material (such as the people form Huston) in blends, others have reproduced natural designs with synthetic components )Harvard, MIT, and MaxPlanck have very important groups on this topic) but the idea to explore the full potential of discarded biomolecules by associating them to the natural design was truly groundbreaking.

I believe chitosan is safe and all that stuff, but unfortunately nobody has ever made an study to objects made of chitosan. While it is easy to guess the outcome, I don’t think Wikipedia is the place to do that kind of assumptions.

As I said, I don’t want to register and I won’t do it. My IP is here which is much detailed information of me. I am sorry if reverting the whole edit looked rude, I tried to edit initially but, in my opinion, your version was full of misconceptions. So actually I reverted to the previous one and change part of the text to include those I considered fair points and to change those sentences easy to misunderstand in the light of your comments.

--24.218.80.193 (talk) 19:28, 26 May 2014 (UTC) 18:33, 26 May 2014 (UTC)

User 24.218.80.193 and COI

Your comments above reveal you are too close to the Harvard work to provide Wikipedia with WP:NPOV, establishing you as WP:COI. I suggest you read WP:NOTJOURNAL, WP:! and WP:SOAP. Your edits deriving from conflict of interest deflect from balanced content as intended by Wikipedia, WP:BALANCE.

-- I don't think this discussion should be here Zerf, since it doesn't have anything to do with actual information about chitosan. I am from the same institution of the people manufacturing the chitosan objects, a fact I have never tried to hide. I don't think I fit in the definition of COI since I don't have any interest on this information and I don't have a personal relation with the authors (and I am not writing about them or our common institution)WP:GF. Be part of the same research institution is as good reason as, for example, be from the same country. Sure Wikipedia could be used to promote points of view and interests from a university or country, but I don’t understand why you assume a biased opinion if there is no personal interest involved. I believe I did a good and neutral review of a topic I know, and I can't see how I personally can benefit from the text I wrote. Actually I deliberately avoided the inclusion of patents (which are very detailed about the process). I sincerely believe your claim of WP:COI lacks of any solid argument. Also I don't understand what kind of WP:BALANCE provided your edition if you didn't make available any reputable source to support the claims you introduced.

--24.218.80.193 (talk) 00:08, 29 May 2014 (UTC)

Further, if indeed the Harvard work is entirely novel (I think it is not because one can clearly see emergence of chitosan product concepts over the last decade), then the Harvard project is disqualified from discussion in the Article, as it would violate WP:OR.

-- From the WP:OR webpage:

In general, the most reliable sources are:

• peer-reviewed journals
• books published by university presses
• university-level textbooks
• magazines, journals, and books published by respected publishing houses
• mainstream newspapers

In my article I have referenced an article published in a peer review journal, Fox news, and Harvard Gazette. All three in the definition of "most reliable sources" as stated in the webpage you have linked. I have also found reviews about this technology in Discovery Channel, National Geographic, the Guardian... Therefore I don't understand on grounds of which facts do you base your accusation of WP:OR, or if you just accused me randomly. I am even surprised you accuse me of OR after you changed my edition of the article to include a whole paragraph claiming facts about the color sorting and the environmental impact which were obviously false and unsupported by data, and you even explained in the talk page that you did that extrapolating results from other research (I suggest you read Hasty generalization).

--24.218.80.193 (talk) 00:08, 29 May 2014 (UTC)

Finally, there are sections of your edits that are overly scientific and detailed, beyond the scope of general readership for an encyclopedia; see WP:5P. --Zefr (talk) 18:38, 27 May 2014 (UTC)

--- I tried to do my best on explaining a complex topic in general terms, and I actually believe I did a good job. On the other hand, your edition of that text started with "Following definition of matrix formation in bioinspired materials" which not only doesn’t make sense, but also is not the kind of sentence and terminology you would use to address the general public.

I sincerely believe all your accusations are unfunded and definitely are not made with the aim of Wikipedia in mind. I already supported with facts the reasons of why you did an awful work on your edition, introducing several major mistakes and inaccuracies WP:ADMIT. I reverted your edition, which I didn’t know at that point, is something rude to do here WP:BITE. Now you are just trying to demonstrate you were right WP:WIN accusing me without evidences, referencing articles you obviously haven’t read, and claiming you are going to edit an article about a topic you already demonstrated you don't know about, as if you were the only editor on Wikipedia WP:3. You have already made clear in this talk page two days ago your "intention to edit again this article". Sincerely, I don't understand and I don't care why anybody would like to edit an article in the encyclopedia about a topic he/she doesn't know. I just came here to make a small edition of an article about a topic I know, and ended up being accused of vandalize the Wikipedia and writing ten times more text in this talk page trying to explain myself than in the actual article WP:OAS. I am not going to edit this article anymore (i.e. you are getting your WP:WIN), feel free to include in Wikipedia anything you learn from your google search about this topic. I hope sooner or later the collaboration of other editors with more patience than me and more expertise than you, will shape the article to an educated form.

--24.218.80.193 (talk) 00:08, 29 May 2014 (UTC)

reverted on 25 May 14

In 2013 Javier G. Fernandez and Donald E. Ingber from the Wyss Institute for Bio-inspired Engineering at Harvard University developed a method to manufacture large scale objects using chitosan. The method is based on the replication of the molecular arrangement of chitosan in natural materials making use of common fabrication methods such as injection molding an molding casting. Once discarded, chitosan objects break down in just a few weeks, releasing high amounts of nitrogen that supports plant growth.[6]

Chitosan objects have been recycled, with the particularity that the dye is introduced and discarded in each recycling step enabling the reuse of the polymer independently of the colorants. This process differs from that of conventional plastics where the colorant is covalently bonded to the structure and different plastics are shorted by colors before reuse.[7] Unlike other plant-based bioplastics (e.g. cellulose, starch...), the main natural sources of chitosan do not compete for land or other resources necessary with basic human needs.[8]

The method employed to manufacture with chitosan is based on the reproduction of a natural hierarchical design with the natural molecules associated to it. The fabrication of large objects with chitosan was the first example of the production of functional objects using this method, and it embodies the next iteration of Shrilk, a material composed of chitin from shrimp shells and a fibroin protein from silk, that replicates the unique properties of living insect cuticle.[9]

Structure

The structure shows a fully-deacetylated molecule. If my understanding of chitosan is correct, then this is somewhat misleading, as chitosan is supposed to have both deacetylated and acetylated residues. — Preceding unsigned comment added by 173.161.140.105 (talk) 17:54, 24 August 2015 (UTC)

I would agree that the monomer units are not correct in this diagram.

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self-healing coatings

About the content below

Potential industrial uses

Scientists have developed a polyurethane coating that heals its own scratches when exposed to sunlight. The self-healing coating uses chitosan incorporated into traditional polymer materials, such as those used in coatings on cars to protect paint. When a scratch damages the chemical structure, the chitosan responds to sunshine by forming chemical chains that bond with other materials in the substance, eventually smoothing the scratch. The process can take less than an hour.

The polymer can only repair itself in the same spot once, and would not work after repeated scratches. Whether this technology can be applied to industrial materials, however, depends on a number of factors, such as long-term persistence of the repair, stiffness and heat resistance of the coating.

References

So scientists from University of Southern Mississippi did some work on incorporating chitosan into paint coatings in a way that "self-healed" when exposed to sunlight. They got this published in Science in 2009 and it got a lot of hoopla (even the NYT mentioned it). A lot of "could be" usefuls... and also a lot of "we are not sure how wide the scratch can be" and "we are not sure if it works more than once" and other questions.

Here we are eight years later; I just looked and there is no evidence this is actually used in products. I went to the website of the USM technology transfer office (here) and they have an excel document you can download that lists their "technologies available for licensing" and the first entry is this invention - entry from the excel table is copied here:

USM Tech ID: 2013.0159

Title: Self-repairing cyclic oxide-substituted chitosan polyurethane networks

Description: Thermosetting polymeric compositions, such as polyurethane compositions, and related methods are provided. The invention relates to coating and polymer compositions and related methods derived from a biodegradable natural polysaccharide compound such as chitosan, pectin, heparin, and combinations thereof reacted to a cyclic oxide compound, such as an oxetane, oxolane or oxepane compound. The compositions and methods of the present invention exhibit self-repairing properties upon exposure to ultraviolet (UV) light. The compositions and methods of the present invention can be used in many coating applications, such as the transportation, packaging, fashion, and biomedical industries.

Patent: 8,658,786

There are zillions of papers out there where academics did something neat that may or may not ever become actual uses. I doesn't make sense to me to keep this kind of thing around, especially under a label of "Potential industrial uses" Jytdog (talk) 18:00, 9 October 2017 (UTC)

Chitosan edit

Why is this a reference spam? A manuscript that’s been accepted by a journal with decent impact factor qualifies to be listed under research section as it helps to annotate the properties of chitosan. Here the paper describes about how different properties can be incorporated into the dental implants using chitosan and another biopolymer. Chitosan did retain the antibacterial activity even if it is mixed with oppositely charged polymer; this is an important finding as it still unclear as to how chitosan kills bacteria (there are a lot of theories, but no concrete evidence yet) — Preceding unsigned comment added by 2607:F220:41D:4425:0:0:0:27C (talk) 19:00, 17 October 2017 (UTC)

We have explained a bunch of times that this the source, PMID 28208793, that is a primary source (see WP:MEDDEF) and we almost never use such sources. The publisher, MDPI, is a borderline predatory publisher. There is no reason to be citing this in WP - a primary source in a low quality journal.

The persistence in trying to force this particular primary into WP can only be explained by the IP being one of the authors, tryinig to abuse WP for promotion. There is no other reason imaginable to be citing this particular primary source about chitosan over the hundreds of primary sources about chitosan that are out there. Read WP:SELFCITE, WP:REFSPAM, and WP:PROMO and please stop wasting our time, and your own. Jytdog (talk) 19:08, 17 October 2017 (UTC)

Weight Loss Studies

The cited study is a 2008 Cochrane review. This was a good meta-analysis, but is now a decade old. There has not been comparably good meta-analyses since, but there have been studies, which tend to show Chitosan being effective for weight loss (such as https://nutritionj.biomedcentral.com/articles/10.1186/s12937-016-0122-8 ). At what point do more recent studies get included in the article?Wikiditm (talk) 08:08, 6 November 2018 (UTC)

We don't edit based on primary sources, but rather reviews.... I just checked pubmed and there is a review from 2016 (PMID 27053066) that has the same conclusion. It cites the cochrane review and an earlier Ernst review, then says "Given the fact that chitosan is supposed to increase fecal fat excretion, clinical trials have evaluated this effect but have found only a non-significant difference in fecal fat excretion after chitosan administration [81, 82]. Finally, one clinical trial compared the effects of orlistat (a pancreatic lipase inhibitor) vs chitosan on fecal fat excretion, finding that the latter did not inhibit dietary fat absorption [83]. Given the aforementioned results, it may be observed that although chitosan might have an effect on weight loss, that loss is not clinically significant and therefore should be interpreted cautiously." Will add it. Jytdog (talk) 15:13, 6 November 2018 (UTC)

Biomedical section

From Chitosan#Biomedical uses:

Chitosan hemostatic products have been shown in testing by the U.S. Marine Corps to quickly stop bleeding and to reduce blood loss, and result in 100% survival of otherwise lethal arterial wounds in swine.

This is a huge claim – a 100% survival rate from otherwise lethal arterial wounds – that can't possible be true as some arterial wounds are going to be lethal pretty much no matter what. I am also doubtful that it's breadth is adequately supported by the given reference, an article from the Journal of Emergency Medicine titled "Experience with Chitosan Dressings in a Civilian EMS System," that reports a study on 30-something cases, according to the abstract. Would someone with access to the full text (doi:10.1016/j.jemermed.2007.05.043, PMID 18024069) see if there is anything in it to support this statement or anything like it? Perhaps there is a more limited claim that is supportable?

Doc James, as an editor with oodles of experience in medical practice and editing WP for medical content, would you like to comment? EdChem (talk) 23:34, 23 December 2018 (UTC)

Sure will take a look. Thanks User:EdChem Doc James (talk · contribs · email) 23:49, 23 December 2018 (UTC)

Yup lots of concerns "Chitosan hemostatic products reduce blood loss in comparison to gauze dressings and increase patient survival."

We do not typically call "swine" patients... Doc James (talk · contribs · email) 00:01, 24 December 2018 (UTC)

Okay have updated. The stuff looks very promising but the evidence is still tentative. Doc James (talk · contribs · email) 00:10, 24 December 2018 (UTC)

Thank you, Doc James, it is appreciated. As for not calling swine patients, one of the challenges of medical ethics is treating the patient in front of you, no matter how reprehensible s/he might be or which politicians are his or her cup of tea... :P EdChem (talk) 00:23, 24 December 2018 (UTC)

References

Primary research does not meet WP:MEDRS

This revert was necessary because most of the sources are from lab research too preliminary to use in the encyclopedia. Sources needed are reviews as described in MEDRS. Zefr (talk) 19:40, 8 December 2022 (UTC)

These sources are lab research and do not meet MEDRS.

References

Zefr (talk) 19:46, 8 December 2022 (UTC)

New section "Chitosan Chemical Modifications"

Hi @User:Smartse, I understand some of your concerns. I have wikified the content. I saw that the chitosan article was lacking any section on chemically modified chitosan, so I find it important to add it. MDPI has probably in average not a great quality, but I selected this text because it is from the well respected Polymers (journal) with an impact factor of 5.0. Let me know if anything else can be improved. Minihaa (talk) 18:29, 30 September 2024 (UTC)

@Minihaa: As you'll have seen the history section that you added had several problems - it copied and pasted from the original source, misrepresented key points and contained irrelevant details (properties not history). This is the kind of thing that MDPI articles have a reputation for. More generally, it is rare that content copied directly from scientific literature is suitable for inclusion in an encyclopaedia as the style of writing differs substantially. Personally as a reader I would prefer to read something short that has been well-researched by an editor rather than excessive detail copied from a free source just because it is legal to do so. SmartSE (talk) 21:33, 3 October 2024 (UTC)

@Smartse: Your rewrite of the history section made me thoughtful. I think I will examine the quality of the respective text more in detail and/or do more editing. I have learned from your feedback; thank you very much for demonstrating it with the history section and investing that much time. I think the existing scientific literature under creative commons licence has a great value, but not sure how to make best use of it. I see less the style as an issue, but I agree with your quality concerns. Minihaa (talk) 18:49, 5 October 2024 (UTC)