Phytochem Class 8 PDF

Class 8 • Polyphenols • Catechol • Recall • Polyphenols – when broken down this means a phenol with more than one ring • Structurally they are enormous molecules and consist of various subgroups • The subgroups involve anthocyanins, rotenone, lignin, lignan, tannins, etc. • • • • What is cate...

Class 8 • Polyphenols • Catechol • Recall • Polyphenols – when broken down this means a phenol with more than one ring • Structurally they are enormous molecules and consist of various subgroups • The subgroups involve anthocyanins, rotenone, lignin, lignan, tannins, etc. • • • • What is catechol? • This is an enzyme • It is not activated till exposed to air, wound response Where can it be found? • They occur naturally in fruits and vegetables, within nearly every single cell • Interestingly enough it has been detected at low levels in ambient air and water along with being present in cigarette smoke Can the naked eye tell when this enzyme has become activated? • Yes actually, by the browning of fruit. • The brown melanin pigment is composed of catechol What is its purpose? • Antibacterial – benzoquinone (a product generated when catechol oxidase and O2 come in contact) is toxic to bacteria • It also assists with preventing decay in damaged plant tissues Class 8 • Resveratrol • Thymol • • What type of phenol is this? • Monoterpene phenol What type of phenol is this? • • Where can this compound be found? • • • Blueberries, grape skins, Japanese knotweed, mulberries, raspberries, and other plants This compound is response generated • • Stilbene Due to pathogens or a wound What type of actions can this perform? • Plants – help to slow the growth of bacterial and fungal infections • Animals – This is an antioxidant compound Popular culture • As resveratrol can be found in red wine, the public eye has zeroed in on the health benefits of this alcoholic beverage • Per liter of resveratrol you can expect to find between 1.5-3mg • So, to receive a therapeutic dose an individual would have to drink between 750-1,500 bottles in a single day • Where can this compound be found? • This can be easily found throughout the Thymus genus, oregano, and other mint family plants • What type of actions can this perform? • Can act as an anti-microbial against mites, as a general pesticide, and when mold grows within bee colonies • Fantastic anti-septic, expectorant, antiviral, antibacterial, and so on with an affinity for the upper respiratory system • Popular culture • Commonly found as a chief medicinal ingredient in thyme essential oil Class 8 • Arbutin • What is this? • A simple phenol • Composed of hydroquinone (commercially used as a skin lightening agent) and D-glucose • Where can it be found? • Within bearberry (Arcostaphylous uva-ursi) • What is its purpose? • It acts as a tyrosinase inhibitor • This amino acid is found in • Mammals (produce melanin) • Insects and spiders (wound repair – exoskeleton) • • How has this compound been used in pop culture? • Similar to psoralen, as a skin-lightening product • Due to this use it may increase the risk of developing cancer, but this is more so related to ingestion N.B. • This compound has been attributed to posses potential anti-cancerous actions against bladder, bone, brain, breast, cervix, colon, liver, prostate, and skin cancers • Sporopollenin • What is sporopollenin? • This is a cross-linked polymer composed of C, H, and O • Where can it be found? • Within spores and pollen • What is it composed of? • Of unknown phenols along with other compounds • What is unique about this compound? • It is extraordinarily stable • Therefore, it is inert and does not really react with anything and makes it very difficult to study • What significance does this hold? • As these compounds are incredibly stable they last long periods of time relatively unchanged if at all. Therefore we can peer into the past and study the types of plant life (paleobotany) and climate (paleoclimatology) that once existed within the local region Class 8 • Catechin • Tannins • What is a catechin? • A polyphenol compound belonging to the flavanol subfamily of flavonoids • • Where can it be found? • Quite abundantly, with the most common dietary sources including green tea, cocoa products, apricots, broad beans, strawberries, wine, etc. What are they? • A group of phenols • Subcategories are separated based upon how they are made, precursors • What subgroups do they have? • Various, however, we fill focus on two • Condensed and hydrolysable tannins • Where can they be found? • What is it composed of? • Of unknown phenols along with other compounds • What is unique about this compound? • It is allelopathic – occurs when an organism produces one or more biochemicals that affect the germination, growth, survival, and reproduction of other organisms within the same community. Catechin’s make it hard for other plants to thrive nearby • Acts a precursor for the construction of some tannins • What significance does this hold in humans? • They are most commonly studied from the source green tea (epigallocatechin gallate – EGCG), where they are found to offer profound antioxidant activity • Otherwise they are rather difficult to study in humans • • • They can be found in various species of plants and their organs The name arose from the German word for tree, as these compounds are found in all trees Activity • They are water soluble • Can either attach in a general (all proteins) or specific way (select proteins) Class 8 • Tanning Hides • Tannins • What is this? • This is a process of making leather from the skin of animals • What is involved? • Two different methods exist • Chromium tanning – is the most popular method worldwide. Chromium salts are used in concentrations of 4-5% • Plant tanning – here oak bark, spruce bark, olive leaves, rhubarb roots, or mimosa or coffee bean shells may be used to produce a “vegetable tanning agent” • Nonetheless in both methods tannins grab hold of collagen in multiple places. From there they begin to crosslink, which strengths the skin dramatically • Profile • Action – astringent, these compounds are physically shrinking the size of your mouth (minute) • This occurs as the secondary metabolites grab onto proteins within ones mouth and shorten it as they attach • Defensive – most animals will avoid these plants due to their off putting taste, i.e. antifeedant • Flavour – sharp and bitter • End product • Permanent alteration in the protein structure of skin • This allows for it to be more durable and less likely to breakdown and colour • Adaptation • Histatin – may act as a defense against the dietary intake of tannins in humans; they form a precipitate when they come in contact with condensed tannins • These peptides also exert antimicrobial and wound closing activities Class 8 • Acacia • Condensed Tannins • • How are they produced? • The common precursor in this subcategory is the amino acid phenylalanine Where is this plant found and who consumes it? • Most commonly on the savannah in Africa • A variety of wildlife but this is the primary source of food for kudu antelope • How does it defend itself? • On a regular day, if this plant is minding it own business it focusses on growth and further developing • On a day where the antelope decides to feed on its leaf’s something different happens • Initial consumption – the antelope enjoys the easy meal and then trots off on its own time • Following consumption till 24 hours later – the plant will release chemical signals to alert other acacia plants within the local area to begin defending themselves from predators • 24-48 hours post-consumption – the plant increases the production of tannins to a toxic amount, if the antelope returned and consumed it again they may die due to the excessive levels of tannins. The antelope would starve as their stomach would be unable to absorb any other compounds, due to the stretching of the proteins within their GIT • Are they a common or rare secondary metabolite? • They are incredibly common • Condensed tannins may one of the most abundant phenolic groups, top 2 or 3 • Where can they found to be most abundant? • These compounds can be found within most woods and barks of trees along with grape seeds and some varieties of pitch Class 8 • Procyanidin B2 • Pycnogenol • • What is procyanidin B2? • • Where can it be found? • • • • They possess antifeedant activity by binding to enzymes that digest food and protein in what you are consuming, lowering nutritional value • Might assist with promoting hair growth, when applied as a topical, as it inhibits the transcription of kinase which is responsible for influencing the pathway that controls hair growth Has shown therapeutic potential in reducing fatty liver disease by remodeling intestinal flora, reducing the production of endotoxins, and down-regulating fatty acid synthesis • This is typically found in a standardized supplement form consisting of 7080% Pycnogenol What is unique about this compound? • This is an incredibly potent antioxidant • Typically, antioxidants are anti-inflammatory but not all have the capacity to modulate effects on the immune system as this does What significance does this hold in humans? • Within French maritime bark What is it composed of? • • A tannin, specifically a condensed tannin Where can it be found? Made from 2 molecules of epicatechin fused together What is unique about this compound? • • • What is it composed of? • • Apples (consuming 10-12 in one sitting can begin to influence changes), grape skin, hawthorn trees (wood and bark has a really amount), nectarines, peaches, plums, and even broad beans What is Pycnogenol? • A condensed tannin What significance does this hold in humans? • Evidence has shown that this compound has been beneficial in dealing with CVS problems, allergies, asthma, high BP, OA, DM, ADHD, disorders of gynaecological reproductive systems, and so on Class 8 • Hydrolysable Tannins • Punicalin • • What is punicalin? • A hydrolysable tannin • Where can it be found? • Most commonly within the rind of pomegranates or in the leaves of country almond (Terminalia catappa) • What is unique about this compound? • Acts as a specific inhibitor within the kidney • It inhibits a protein that plays a role in regulating pH • Carbonic anhydrase is inhibited, bicarbonate buffer system is not thrown out of whack • What significance does this hold in humans? • Anti-inflammatory, anti-viral, chemotherapeutic • Glaucoma and seizure treatment • Chronic altitude sickness can be treated this way by correcting alkalosis rapidly, instead of taking several days for the kidneys to catch up • • • • What are they? • Phenols • Tannins to be exact How are they different from the other type of tannin we have covered today? • Condensed tannins are not broken down, as easily, as hydrolysable • Water does not cleave condensed tannins but it will to hydrolysable tannins If they are broken down so easily, what do they turn into? • They are cleaved easily into acids • Most turn into gallic acid How are they produced? • While phenylalanine is one of the end products of the shikimic acid pathway other compounds are produced along the way • These tannins are made up of one of those intermediaries In general, • They exert anti-cancer, anti-angiogenic, antioxidant, anti-inflammatory, and anti-ulcerative properties • They are commonly associated with oak and chestnut Class 8 • Gallic Acid • Microorganisms • What is this? • A hydrolysable tannin • • Where can it be found? • Most hydrolysable tannins convert to gallic acid once mixed in the stomach • What is unique about this compound? • This is a weak carbonic anhydrase inhibitor, much less than punicalin • What significance does this hold in humans? • From a modern perspective they can exhibit anticancerous activity via stimulating apoptosis in tumor cells and suppressing their migration to colonize new sites Are only large organisms affected by tannins? • • • How are they affected by tannins? • Recall, they bind to proteins (usually enzymes) and render them useless • The large or small organism is then unable to appropriately breakdown, digest, and absorb the nutrients they attempted to obtain What activity are the tannins responsible for in this scenario? • • All organisms large and small are affected by tannins The tannins act as antimicrobial agents, fending off bacteria, fungi, and viruses Example – altering the speed of decomposition • Oak (Quercus spp.) – this genus tends to contain higher amounts of tannins than most others and therefore tend to be the longest lasting leafs from fall, into spring and summer from the year before • Alder (Alnus spp.) – this genus contains fewer tannins than Oak and as a result decomposes much faster, in as little as 6 weeks Class 8 • Carbon Cycle • What is the carbon cycle? • This is the process in which C atoms continually travel from the atmosphere to the earth and then back into the atmosphere • We can view the earth as a closed system from this perspective • The amount of C available does not change • How does todays lecture tie into this? • Life forms on earth are C based, so when they pass away they shed this element to be reused in the very cycle that allowed for them to be alive • Plants contain tannins, which are compounds that act as secondary metabolites • The percentage of tannins within a particular plant determine their rate of decay, i.e., the more tannins they have the slower the rate is and vice versa. • As a plant decays, rapidly or slowly, it will release C back into the cycle • Is this the same across the planet? • No, this is not the same across the planet as elevation and climate vary • Warmer regions of the planet have higher levels of activity occurring along with condensed tannins, harder to breakdown • Cooler regions of the planet have seasonal variations in the level of activity occurring along with hydrolysable tannins, easier to breakdown • Tannins and Ecology • Where are the subgroups of tannins most commonly found? • Condensed tannins are more common in the tropics • Hydrolysable tannins are more common in temperate climates • Western science based study • Recall that this area of study has thus far focussed on 1-2 variables • So, studying individual compounds extracted from plant material is a straight forward task • However, this method of study is limited when taking a look at the bigger picture such as the environment. Due to all of the factors affecting the presentation of chemicals that are interacting with other compounds • Where is a characteristic place you can find large amounts of tannins readily available? • Within blackwater rivers; they are essentially a cold infused tea that has been continuously steeping with more leaves being added day after day