FLAVANONES
Hesperidin, Naringenin
Flavanones
The most abundant citrus flavanoid; 98% in grapefruit, 96% in limes and 90% in lemons
A type of flavanoid with several chemical variations.
These include Hesperidin, Naringenin, Eriodictyol, Sterubin, Butin, and many others
Primary focus today is HESPERIDIN
Highest content is in lemons
CITRUSGenus of
flowering plants in the Rue family, Rutaceae
Lemons are further classified as citrus limon
Fruit is hesperidium
“Lemons, …. commonly known as the fruit that evokes images of sunshine and the sweet smiles of children standing roadside at their homemade lemonade stands”
G. Mateljan, www.whfoods.com
The History of Lemons
Lemons originally developed as a cross of lime & citron and thought to have originated in China and India 2500 years ago
Brought to the Americas by Christopher Columbus in 1493
Prized by California Gold Rush miners to prevent scurvy;1849
United States, Italy, Spain, Greece, Israel, &Turkey are the main producers in the marketplace today
Availability in the marketplace
California/Arizona Citrus produce 95% of the lemons in the US
Availability in the marketplace
Florida Citrus
Availability in the marketplace
Texas Citrus
Imported Citrus
Lemon Cultivars Other Names Location(s)
Bears Florida
Berna Verna, Bernia, Vernia Spain, Algeria, Morocco
Eureka S. Africa, Argentina, Australia, California, Greece, Israel, Mexico, Pakistan, China, Arizona, Florida
Femminello ovale or Feminello comune
Commune, Ruvittaru Sicily
Interdonato Speciale Sicily
Kusner Russia
Lisbon California, Algeria, China, Greece, Mexico, Morocco, Argentina, Portugal
Mesero Fino, Primifiori Italy, Spain
Monachello Moscatello Italy
Monroe California
Sicilian lemon Brazil
Villafranca Sicily, California
Listing of lemon cultivars of commercial importance worldwide
Health Benefits
Contain important natural chemical components: Phenolic compounds - mainly flavonoids Vitamins - especially vitamin C Minerals – especially potassium Fiber Carotenoids Essential oils
Health promoting properties associated with vitamin C and flavanoid content due to natural antioxidant characteristics
Important part of a balanced diet for role in prevention of disease
Health Benefits
Experimental data from in vitro, in vivo and clinical trials in support of the health-promoting activity of lemon and its bioactive compounds: Cancer - esophagus, mouth, stomach and colon Cardiovascular, coronary heart disease and oxidative
damage Lipid metabolism and obesity Gastrointestinal diseases Diabetes Antimicrobial activity Urinary diseases Psychiatric diseases Bone protection
Health Benefits
Citrus fruits may be among the fruits with the greatest cancer fighting potential.
This is especially true in the cancers of the esophagus, mouth, stomach and colon
Anti cancer benefits are mainly due to significant quantities of monoterpenes and flavanones which are believed to cut the risks of cancers of the digestive track in half.
These compounds reduce cancer risks in two significant ways:1. Interfere with some of the processes necessary for cancer
cell growth, making it difficult for tumors to develop.
2. Inhibit inflammation, a stimulus for cancer cell growth.
Health Benefits
Citrus flavonoids act as modulators of tyrosine kinases – important implications in treatment of cancer
Eriocitrin (from lemon juices and its metabolites) was tested in different Citrus juices by Ogata et al. and showed that it induced apoptosis in HL-60 cells
Hesperidin in different citrus juices showed antiproliferative activity
Lemons showed relatively potent antiproliferative activities on HepG2 human liver cancer cell growth
Other studies showed eriocitrin as an inhibitory compound acting against both rat platelet 5- and 12-lipoxygenases, and its aglycone, eriodictyol, was a much more potent inhibitor of these lipoxygenases involved in biosynthesis of various bioregulators closely related to the pathogenesis of several diseases such as allergies, atherosclerosis and cancer
Health Benefits
Digestion Lemon added to warm water helps the digestive tract. Natural
acidity helps to stimulate the liver increasing bile secretions. This causes the digestive tract to move more efficiently, resulting in better digestion. Lemon water can also help to eliminate constipation and nausea and may also treat worm infestations of the digestive tract.
Flush Toxins Lemon also has antibacterial properties. Good for throat
infections and tonsillitis because of its antibacterial content and diuretic properties. When consumed with water, has the ability to flush toxins and bacteria out of the system, making it an especially effective treatment for ailments of the blood and organic systems of the body.
Health Risks
Gastroesophageal Reflux Acidic citrus fruits may increase esophageal irritation and
exacerbate GERD symptoms. Acidity can also lead to gastric ulcer irritation.
Dental Erosion The acids in lemon juice eat away at the enamel, the shiny
surface component of teeth that protects from decay. Erosion can lead to surface staining, cavities and sensitivity if prolonged exposure continues.
Medicine Interactions The FDA has clearly defined a link between altered drug
metabolism and citrus fruit juices. As little as 120mL of lemon juice contains 5.9g of citric acid, which is shown to decrease the blood levels of chloroquine, which is used by those entering an area with a high risk of malarial infection.
Health Risks
Lemon and Lime Peels and Oxalates The peels of lemons are among a small number of foods that contain
measurable amounts of oxalates. When oxalates become too concentrated in body fluids, they can crystallize and cause health problems. So, individuals with already existing and untreated kidney or gallbladder problems may want to avoid eating lemon or lime peels.
Lemons and Limes and Wax Coatings Conventionally grown lemons may be waxed to protect from bruising
during shipping. Plant, insect, animal or petroleum-based waxes may be used. Carnauba palm is the most common plant-source wax. Other compounds, such as ethyl alcohol or ethanol, are added to the waxes for consistency, milk casein for "film formers" and soaps for flowing agents. Since you may not be able to determine the source of waxes, another good reason to choose organically grown lemons.
Flavonone content in lemons and pure lemon juice
http://www.phenol-explorer.eu/
Varieties of Lemons
Eureka – o texturized skin, a short neck at one end and
a few seedso Sour flavoro Originated in Californiao Forms an open, spreading tree, with
relatively few branches and twigs which are virtually thornless
o Production occurs mostly in spring and summer
Varieties of Lemons
Lisbon – o smoother skin, no neck and is generally
seedlesso Sour flavoro Originated in Australia o Characterized by a rather dense tree
having numerous upright, thorny brancheso Production occurs mostly in summer and fall
Varieties of Lemons
Meyero They are more round a have a smooth
unpitted skino As they mature they become deep
yellow to orange takes on a deep yellow to orange color when mature.
o tangy aroma and less acidic. o introduced from China in 1908o The tree is spreading and relatively small, nearly thornless and more cold tolerant than true lemonso Production occurs mostly in winter
Major Lemon Growers Worldwide
González-Molina E., Domínguez-Perles R., Moreno D.A., García-Viguera C. Natural bioactive compounds of Citrus limon for food and health. Journal of Pharmaceutical and Biomedical Analysis.2010:51:327–345.
Terry, Leon A. Health-promoting Properties of Fruits and Vegetables. Wallingford, Oxfordshire: CABI, 2011.96-105.
Bioavailability of flavonoids in Lemons
Citrus flavonoids can exist as free aglycones but most of them commonly occur as C- or O-glycosides
In lemons the sugars, rutinosides are tasteless
Distribution throughout the fruit: Juice: hesperidin and eriocitrin Peel: hesperidin, eriocitrin, neoeriocitrin,
neohesperidin and naringin and minor amt of narirutin
Seeds: hesperidin and eriocitrin, low amts of naringin
Guihua X., Donghong L., Jianchu C., Xingqian Y., Yaqin M., John S. Juice components and antioxidant capacity of citrus varieties cultivated in China. Food Chemistry.2008:106:545–551.
Growing Conditions
CLIMATE:o Not cold toleranto Mediterranean climate
Soil Type:o Well adapted to virtually any soil
typeo Require full sunlight for optimum
growth and productiono Good drainage
Growing Conditions and Bioactivity
The concentration of bioactives is influenced by the following factors:o Cultivar (rootstock & scion)o Climateo Cultural practices during
productiono Position of the fruit treeo Fruit maturationo Post harvest treatments
Handling, storage and transportation of fruit
Absorption of flavonoids
O-glucosides undergo intestinal hydrolysis to release aglycones
Hesperidin and hesperetin may be metabolized into hesperetin after oral administration
Eriocitrin is metabolized to eriodictyol (aglycone) in intestional flora
Post ingestion hesperetin and erodictyol were detected in human urine and plasma as the glucuro-and/or sulfo-conjugates - suggesting these undergo extensive phase II metabolism
Most absorbed Citrus flavanones undergo glucuronidation before urinary excretion
Storing Lemons: nutrient content
Fruit: maintains its levels of juice, vitamins, minerals, fibers and carbohydrates for several months
Fruit and juice: suffer degradation of vitamin C during storage or industrial process (pasteurization)
Oxygen, heat light, storage temperature, and storage time affect ascorbic acid retention in juices.
To prevent loss of ascorbic acid: o Keep at 0-5o C and protected from water
loss Pasteurization does not modify hesperidin
content
Storage and Processing
•Stay fresh at room temperature, away from exposure to sunlight, for about one week.
•Can be stored in the refrigerator crisper and will keep for about four weeks.
•Fresh juice storage; squeeze into ice trays and freeze stored in plastic freezer bags
•Zest storage; dry and store in a cool dry place in an airtight glass container.
Choosing the best Lemon
• Look for thin skinned lemons since they have more flesh and juice; choose lemons that are heavy for their size, with peels that have a grainy surface
• Bright yellow fruit indicates that the lemon is at the peak of ripeness.
Cooking with Citrus Peel
•Xu et al. reported in 2008 on the efficiency of heat infusion to extract both minerals and phenolic compounds, including flavanone glycosides from citrus varieties.
•Peels of 2 varieties ( Satsuma & Ponkan mandarin) were selected & boiled in hot water to extract minerals & phenolics.
•The result showed that this was an efficient means of extracting many phenolics and minerals, however, hesperidin was the most difficult to extract, suggesting that it is more tightly bound within its food matrix there.
•The study also showed that the antioxidant capacity of the citrus peels boiled in hot water was almost the same as that extracted with methanol.
•Lengthening time or raising temperature extracted more in 2 studies
Cooking with Lemons
•The bioactives in citrus partly determine the unique flavor. Neohesperidosides in grapefruits are intensively bitter, but rutinosides, in lemons, are tasteless.
•Peels are the main fiber content in lemons & pectin is the major component of fiber in the lemon.
•Recently, research has been focused on the lemon in comparison to major carotenoid components of orange species varieties, showing that lemon contains reasonable quantities of carotenoids for a daily nutritional source of these bioactives.
•Lemons sprayed with pesticides may be toxic for humans or animals, but also prompt changes in essential oil composition as an effect on plant metabolism.
Cooking with Lemons
• The juice can be used to prevent browning
• The acidic lemon juice can be exchanged for vinegar in dressings
•Limoncello liquor is made by macerating lemon peels free of pesticide residues in ethanol, water &sugar.
• Preserved lemons are a popular condiment in Indian, North African, and Moroccan cuisines
•Candied Lemon Peel can make great holiday gifts and can be dipped in dark chocolate for an added bioactive bonus!
•Lemon juice in water stimulates bile flow in the mornings or before meals.
Cooking with Lemons; Juicing
• The acidity of lemon juice brings everything into balance as you finish preparing a dish.
• To get the most juice out, press down on it while rolling it back and forth on the counter, then juice it.
• A good juicy lemon, contains ¼ cup of fresh lemon juice.
Natural beauty tips!
• Natural facial-boil orange and grapefruit peels with 2 cups of non-carbonated mineral water. Strain liquid into a bottle and apply to face twice daily. Keep refrigerated
• Skin bracer-blend juice of half a grapefruit with warm water and splash on face immediately after washing to tighten pores.
• To soften rough red elbows, dip and rub into grapefruit halves for two or three days.
• To soften cuticles and whiten nails, mix 3 cups warm water with the juice of half a grapefruit. Soak fingers for 5 minutes.
RecipeIngredientsZest from 1 organic lemon, finely diced1 cup water1/2 cup turbinado1/2 cup fresh lemon juice1/2 cup carbonated mineral water6 strips of lemon zest, for garnish
DirectionsIn a saucepan, stir together the lemon zest, 1 cup of water and turbinado. Bring to a boil, reduce heat to medium and simmer for 5 minutes. Remove from heat, and allow to cool.In a bowl, stir together the lemon syrup, lemon juice and mineral water. Pour into an ice cream maker, and freeze according to the manufacturer's instructions. Garnish each serving with a twist of lemon peel.
If you do not have an ice cream maker, you may freeze it in a tall canister. Freeze for 1 1/2 hours. Remove and stir with a whisk. Return to the freezer and stir about once every hour for about 4 hours. The more times you stir, the more air will be incorporated, resulting in a lighter finished product.
Discussion Topic
References
http://www.whfoods.com/genpage.php?tname=foodspice&dbid=27http://www.phenol-explorer.eu/http://www.sunkist.com/kids/facts/lemons.asp
The End