Friday, 4 August 2017

Ziziphus mauritiana (Betulinic acid) dược liệu kháng HL-60

Ziziphus mauritiana (Betulinic acid) dược liệu kháng HL-60

From Wikipedia, the free encyclopedia
Ziziphus mauritiana
Ziziphus mauritiana fruit 2.jpg
Scientific classification
Kingdom:Plantae
(unranked):Angiosperms
(unranked):Eudicots
(unranked):Rosids
Order:Rosales
Family:Rhamnaceae
Genus:Ziziphus
Species:Z. mauritiana
Binomial name
Ziziphus mauritiana
Lam.
Ziziphus mauritiana, also known as Chinese date,[1] berChinee/Chinkee applejujubeIndian plum, พุทรา (Thailand), Regi panduIndian jujubedunks (in Barbados) and masau, is a tropical fruit tree species belonging to the family Rhamnaceae.
Ziziphus mauritiana is a spiny, evergreen shrub or small tree up to 15 m high, with trunk 40 cm or more in diameter; spreading crown; stipular spines and many drooping branches. The fruit is of variable shape and size. It can be oval, obovate, oblong or round, and can be 1-2.5 in (2.5-6.25 cm) long, depending on the variety. The flesh is white and crisp. When slightly underipe, this fruit is a bit juicy and has a pleasant aroma. The fruit's skin is smooth, glossy, thin but tight.
The species is believed to have originated in Indo-Malaysian region of South-East Asia.[2] It is now widely naturalised throughout the Old World tropics from Southern Africa through the Middle East to the Indian Subcontinent and ChinaIndomalaya, and into Australasia and the Pacific Islands.[3] It can form dense stands and become invasive in some areas, including Fiji and Australia and has become a serious environmental weed in Northern Australia. It is a fast-growing tree with a medium lifespan, that can quickly reach up to 10–40 ft (3 to 12 m) tall.
In Queensland, Australia, it is known as the Chinee/Chinkee apple as it was believed to be introduced by Chinese miners to areas such as Charters TowersRavenswood and Hughenden.[4]

Botany[edit]

Z. mauritiana tree
Indian jujube (Ber) - Fresh Fruit
Nutritional value per 100 g (3.5 oz)
Energy24.76 kJ (5.92 kcal)
17 g
Sugars5.4-10.5 g
Dietary fibre0.60 g
0.07 g
0.8 g
Vitamins
Thiamine (B1)
(2%)
0.022 mg
Riboflavin (B2)
(2%)
0.029 mg
Niacin (B3)
(5%)
0.78 mg
Minerals
Calcium
(3%)
25.6 mg
Iron
(8%)
1.1 mg
Phosphorus
(4%)
26.8 mg
Other constituents
Water81.6-83.0 g

Percentages are roughly approximated using US recommendations for adults.
Source: USDA Nutrient Database
Ziziphus mauritiana is a medium-sized tree that grows vigorously and has a rapidly developing taproot, a necessary adaptation to drought conditions. The species varies widely in height, from a bushy shrub 1.5 to 2 m tall, to a tree 10 to 12 m tall with a trunk diameter of about 30 cm. Z. mauritiana may be erect or wide-spreading, with gracefully drooping thorny branches, zigzag branchlets, thornless or set with short, sharp straight or hooked spines.[5]
The leaves are alternate, ovate or oblong elliptic with rounded apex, with 3 depressed longitudinal veins at the base. The leaves are about 2.5 to 3.2 cm long and 1.8 to 3.8 cm wide having fine tooth at margin. It is dark-green and glossy on the upper side and pubescent and pale-green to grey-green on the lower side. Depending on the climate, the foliage of the Z. mauritiana may be evergreen or deciduous.
The flowers are tiny, yellow, 5-petalled and are usually in twos and threes in the leaf axils. Flowers are white or greenish white and the fruits are orange to brown, 2–3 cm long, with edible white pulp surrounding a 2-locular pyrene.[3]
This quick growing tree starts producing fruits within three years. The fruit is a soft, juicy, drupe that is 2.5 cm diameter though with sophisticated cultivation the fruit size may reach up to 6.25 cm long and 4.5 cm wide. The form may be oval, obovate, round or oblong; the skin smooth or rough, glossy, thin but tough. The fruit ripen at different times even on a single tree. Fruits are first green, turning yellow as they ripen. The fully mature fruit is entirely red, soft, juicy with wrinkled skin and has a pleasant aroma. The ripe fruit is sweet and sour in taste. Both flesh texture and taste are reminiscent of apples. When under ripe the flesh is white and crispy, acid to subacid to sweet in taste. Fully ripe fruits are less crisp and somewhat mealy; overripe fruits are wrinkled, the flesh buff-coloured, soft, spongy and musky. At first the aroma is apple like and pleasant but it becomes peculiarly musky when overripe. There is a single, hard, oval or oblate, rough central stone which contains 2 elliptic, brown seeds, 1/4 in (6mm) long.

Ecology[edit]

Ziziphus mauritiana is hardy tree that copes with extreme temperatures and thrives under rather dry conditions with an annual rainfall of 6 to 88.5 in (15–225 cm). In Fiji, sometimes naturalised Ber trees grow along roadsides and in agricultural land, usually near sea level but occasionally up to an elevation of about 600 m. It also grows well on laterite, medium black soils with good drainage, or sandy, gravelly, alluvial soil of dry river-beds where it is vigorously spontaneous. In Australia, this species grows on a wide variety of soil types, including cracking clays, solodic soils and deep alluvials, in the tropics and sub-tropics where the average annual rainfall is in the range 470-1200mm. In the drier parts of this range, it grows best in riparian zones.[5] Commercial cultivation usually extends up to 1000 m. Beyond this elevation trees do not perform well, and cultivation becomes less economical.[6]
The tree has a high tolerance to both water-logging and drought and can grow where annual rainfall ranges from 125 to 2,225 mm, but is more widespread in areas with an annual rainfall of 300 to 500 mm. In China and India, wild trees are found up to an elevation of 5,400 ft (1,650 m). In India, the minimum shade temperature for survival is 7–13° and the maximum temperature is 50 °C. Studies report that this species flourishes in alkaline soils with a pH as high as 9.2. However, deep sandy loam to loamy soils with neutral or slightly alkaline pH are considered optimum for growth.[7] In India, the tree grows best on sandy loam, neutral or slightly alkaline.
In India, there are 90 or more cultivars depending on the habit of the tree, leaf shape, fruit form, size, color, flavor, keeping quality, and fruiting season. Among the important cultivars, eleven are described in the encyclopaedic Wealth of India: 'Banarasi (or Banarsi) Pewandi', 'Dandan', 'Kaithli' ('Patham'), 'Muria Mahrara', 'Narikelee', 'Nazuk', 'Sanauri 1', 'Sanauri 5', 'Thornless' and 'Umran' ('Umri'). The skin of most is smooth and greenish-yellow to yellow.[1]

Reproductive biology[edit]

Some cultivars attain anthesis early in the morning, others do so later in the day. The flowers are protandrous. Hence, fruit set depends on cross-pollination by insects attracted by the fragrance and nectar. Pollen of the Indian jujube is thick and heavy. It is not airborne but is transferred from flower to flower by honeybees.[6] The flowers are pollinated by ants and other insects, and in the wild state the trees do not set fruits by self-pollination. Ber propagates by seeds, seedlings, direct sowing, root suckers as well as by cuttings. Ber seeds are spread by birds, native animals, stock, feral pigs and humans who eat the fruit and expel the seeds. Seeds may remain viable for 2½ years but the rate of germination declines with age.[1] Cross-incompatibility occurs, and cultivars have to be matched for good fruit set; some cultivars produce good crops parthenocarpically.

Propagation[edit]

Fruits at various stages of ripeness, with cracked pit showing the two seeds
Ziziphus mauritiana is one of the two Ziziphus species that have considerable horticulture importance, the other being Chinese jujube (Z. zizyphus). Indian jujube is more tropical whereas Chinese jujube is a more cold hardy species.[1]
Propagation is most commonly from seed, where pretreatment is beneficial. Storage of the seed for 4 months to let it after-ripen improves germination. The hard stone restricts germination and cracking the shell or extraction of seeds hastens germination. Without pretreatment the seeds normally germinate within six weeks whereas extracted seeds only need one week to germinate
Seedlings to be used as rootstock can be raised from seed. Several studies indicate that germination can be improved by soaking seeds in sulfuric acid. Germination time can also be shortened to 7 days by carefully cracking the endocarp. Ber seedlings do not tolerate transplanting, therefore the best alternatives are to sow the seeds directly in the field or to use polythene tubes placed in the nursery bed. Seedlings are ready for budding in 3 to 4 months. In addition, seedlings from the wild cultivars can be converted into improved cultivars by top-working and grafting. Nurseries are used for large scale seedling multiplication and graft production. The seedlings should also be given full light. The seedlings may need as long as 15 months in the nursery before planting in the field.[6]
Scientists in India have standardised propagation techniques for Ber establishment. Budding is the easiest method of vegetative propagation used for improved cultivars. Different types of budding techniques have been utilised with ring-budding and shield-budding being the most successful. Wild varieties of ber are usually used as the root-stock. The most common being Z. rotundifolia in India and Z. spina-christi in Africa.[1]

Season and harvesting[edit]

Ripe and unripe jujube fruits for sale at the Luangwa Bridge in Zambia.
Plants are capable of seed production once they reach a height of about 1 metre. Wild-growing plants in northern Australia may take 8 years to reach this size. In Australia, plants growing under natural conditions are capable of producing seeds once they reach a height of about 1m. Plants between 1 and 2m high produce, on average, less than five fruits per season. Large plants (>5m high) can produce 5000 or more fruits in a single season.
In India, some types ripen as early as October, others from mid-February to mid-March, others in March, or mid-March, to the end of April. In the Assiut Governorate, there are 2 crops a year, the main in early spring, the second in the fall. In India the trees flower in July to October and fruits are formed soon after. In February–March the fruits are mature and in some places a second crop is produced in the fall. Pickings are done by hand from ladders and about 110 lbs (50 kg)is harvested per day. The fruits remaining on the tree are shaken down. Only fully mature fruits are picked directly from the tree. They are transported in open bags to avoid fermentation.[8]
Seedling trees bear 5,000 to 10,000 small fruits per year in India. Superior grafted trees may yield as many as 30,000 fruits. The best cultivar in India, with fruits normally averaging 30 to the lb (66 to the kg), yields 175 lbs (77 kg) annually. Special cultural treatment increases both fruit size and yield.

World production and yield[edit]

The major production regions for Indian jujube are the arid and semi arid regions of India. From 1984 to 1995 with improved cultivars the production was 0.9 million tonnes on a land of 88,000 ha. The crop is also grown in PakistanBangladesh and parts of Africa. Trees in northern India yield 80 to 200 kg of fresh fruit/tree/year when the trees are in their prime bearing age of 10–20 years.[2]

Uses[edit]

The fruit is eaten raw, pickled or used in beverages. It is quite nutritious and rich in vitamin C. It is second only to guava and much higher than citrus or apples. In India, the ripe fruits are mostly consumed raw, but are sometimes stewed. Slightly underripe fruits are candied by a process of pricking, immersing in a salt solution. Ripe fruits are preserved by sun-drying and a powder is prepared for out-of-season purposes. It contains 20 to 30% sugar, up to 2.5% protein and 12.8% carbohydrates. Fruits are also eaten in other forms, such as dried, candied, pickled, as juice, or as ber butter. In Ethiopia, the fruits are used to stupefy fish.
The leaves are readily eaten by camels, cattle and goats and are considered nutritious.[9]
In India and Queensland, the flowers are rated as a minor source of nectar for honeybees. The honey is light and of fair flavor.
Ber timber is hard, strong, fine-grained, fine-textured, tough, durable, and reddish in colour. It has been used to line wells, to make legs for bedsteads, boat ribs, agricultural implements, tool handles, and other lathe-turned items. The branches are used as framework in house construction and the wood makes good charcoal with a heat content of almost 4,900 kcal per kg.[1] In addition, this species is used as firewood in many areas. In tropical Africa, the flexible branches are wrapped as retaining bands around conical thatched roofs of huts, and are twined together to form thorny corral walls to retain livestock.
Ziziphus mauritiana bark
The fruits are applied on cuts and ulcers; are employed in pulmonary ailments and fevers; and, mixed with salt and chili peppers, are given in indigestion and biliousness. The dried ripe fruit is a mild laxative. The seeds are sedative and are taken, sometimes with buttermilk, to halt nausea, vomiting, and abdominal pains in pregnancy. They check diarrhea, and are poulticed on wounds. Mixed with oil, they are rubbed on rheumatic areas. The leaves are applied as poultices and are helpful in liver troubles, asthma and fever and, together with catechu, are administered when an astringent is needed, as on wounds. The bitter, astringent bark decoction is taken to halt diarrhea and dysentery and relieve gingivitis. The bark paste is applied on sores. The root is purgative. A root decoction is given as a febrifuge, taenicide and emmenagogue, and the powdered root is dusted on wounds. Juice of the root bark is said to alleviate gout and rheumatism. Strong doses of the bark or root may be toxic. An infusion of the flowers serves as an eye lotion.[10]
The fatty-acid methyl ester of Z. mauritiana seed oil meets all of the major biodiesel requirements in the USA (ASTM D 6751-02, ASTM PS 121-99), Germany (DIN V 51606) and European Union (EN 14214). The average oil yield is 4.95 kg oil/tree or 1371 kg oil/hectare, and arid or semi-arid regions may be utilised due to its drought resistance.

Pests and diseases[edit]

The greatest enemies of the jujube are fruit flies. Some cultivars are more susceptible than others, the flies preferring the largest, sweetest fruits, 100% of which may be attacked while on a neighbouring tree, bearing a smaller, less-sweet type, only 2% of the crop may be damaged. The larvae pupate in the soil and it has been found that treatment of the ground beneath the tree helps reduce the problem. Control is possible with regular and effective spraying of insecticide.[1]
A leaf-eating caterpillar and the green slug caterpillar attack the foliage. Mites form scale-like galls on twigs, retarding growth and reducing the fruit crop. Lesser pests include a small caterpillar, Meridarches scyrodes, that bores into the fruit.
The tree is subject to shrouding by a parasitic vine . Powdery mildew causes defoliation and fruit-drop, but it can be adequately controlled.[6] Lesser diseases are sooty mould, brown rot and leaf-spot. Leafspot results from infestation by Cercospora spp. and Isariopsis indica var. zizyphi. In 1973, a witches'-broom disease caused by a mycoplasma-like organism was found in jujube plants near Poona University. It proved to be transmitted by grafting or budding diseased scions onto healthy Z. mauritiana seedlings. Leaf rust, caused by Phakopsora zizyphivulgaris, ranges from mild to severe on all commercial cultivars in the Punjab.
In storage, the fruits may be spotted by fungi. Fruit rots are caused by Fusarium spp., Nigrospora oryzaeEpicoccum nigrum, and Glomerella cingulata.

Betula pubescens (Betulinic acid) dược liệu kháng HL-60

Betula pubescens (Betulinic acid) dược liệu kháng HL-60

Betula pubescens

From Wikipedia, the free encyclopedia
Betula pubescens
Brzoza omszona Betula pubescens.jpg
Scientific classification
Kingdom:Plantae
(unranked):Angiosperms
(unranked):Eudicots
(unranked):Rosids
Order:Fagales
Family:Betulaceae
Genus:Betula
Subgenus:Betula
Species:B. pubescens
Binomial name
Betula pubescens
Ehrh.
Betula pubescens range.svg
Distribution map
Synonyms
Betula alba
Betula pubescens (syn. Betula alba), commonly known as downy birch and also as moor birchwhite birchEuropean white birch or hairy birch, is a species of deciduous tree, native and abundant throughout northern Europe and northern Asia, growing farther north than any other broadleaf tree. It is closely related to, and often confused with, the silver birch (B. pendula), but grows in wetter places with heavier soils and poorer drainage; smaller trees can also be confused with the dwarf birch (B. nana).
Three varieties are recognised and it hybridises with the silver and dwarf birches. A number of cultivars have been developed but many are no longer in cultivation. The larva of the autumnal moth (Epirrita autumnata) feeds on the foliage and in some years, large areas of birch forest can be defoliated by this insect. A large number of fungi are associated with the tree and certain pathogenic fungi are the causal agents of birch dieback disease.
The tree is a pioneer species, readily colonising cleared land, but later being replaced by taller, more long-lived species. The bark can be stripped off without killing the tree and the bark and the timber is used for turnery and in the manufacture of plywood, furniture, shelves, coffins, matches, toys and wood flooring. The inner bark is edible and can be ground up and used in bread-making, as it still is at Easter in the traditional Finnish mämmi, or eaten in times of famine. The rising sap in spring is used to make refreshing drinks, wines, ales and liqueurs and various parts of the tree have been used in herbal medicine.

Description[edit]

Betula pubescens is commonly known as downy birch, with other common names including moor birch, white birch, European white birch or hairy birch.[2] It is a deciduous tree growing to 10 to 20 m (33 to 66 ft) tall (rarely to 27 m), with a slender crown and a trunk up to 70 cm (28 in) (exceptionally 1 m) in diameter, with smooth but dull grey-white bark finely marked with dark horizontal lenticels. The shoots are grey-brown with fine downy. The leaves are ovate-acute, 2 to 5 cm (0.8 to 2.0 in) long and 1.5 to 4.5 cm (0.6 to 1.8 in) broad, with a finely serrated margin. The flowers are wind-pollinated catkins, produced in early spring before the leaves. The fruit is a pendulous, cylindrical aggregate 1 to 4 cm (0.4 to 1.6 in) long and 5 to 7 mm (0.2 to 0.3 in) wide which disintegrates at maturity, releasing the individual seeds; these seeds are 2 mm (0.08 in) long with two small wings along the side.[2][3]

Species identification[edit]

B. pubescens is closely related to, and often confused with, the silver birch (B. pendula). Many North American texts treat the two species as conspecific (and cause confusion by combining the downy birch's alternative vernacular name, white birch, with the scientific name B. pendula of the other species), but they are regarded as distinct species throughout Europe.[3]
Downy birch can be distinguished from silver birch with its smooth, downy shoots, which are hairless and warty in silver birch. The bark of the downy birch is a dull greyish white, whereas the silver birch has striking white, papery bark with black fissures. The leaf margins also differ, finely serrated in downy birch, coarsely double-toothed in silver birch. The two have differences in habitat requirements, with downy birch more common on wet, poorly drained sites, such as clays and peat bogs, and silver birch found mainly on dry, sandy soils.[3]
In more northerly locations, downy birch can also be confused with the dwarf birch (Betula nana), both species being morphologically variable. All three species can be distinguished cytologically, silver birch and dwarf birch being diploid (with two sets of chromosomes), whereas downy birch is tetraploid (with four sets of chromosomes). In Iceland, dwarf birch and downy birch sometimes hybridise, the resulting plants being triploid (with three sets of chromosomes).[4]

Distribution and habitat[edit]

Betula pubescens near a path encircling a lake inside the Arctic Circle in Tromsø
Betula pubescens has a wide distribution in northern and central Europe and Asia. Its range extends from Newfoundland, Iceland, the British Isles and Spain eastwards across northern and central Europe and Asia as far as the Lake Baikal region in Siberia. The range extends southwards to about 40°N, its southernmost limit being Turkey, the Caucasus and the Altai Mountains.[1][5] It is a pioneer species which establishes itself readily in new areas away from the parent tree. This allows other woodland trees to become established and the birch, a short-lived tree, eventually gets crowded out as its seedlings are intolerant of shady conditions.[6]
Downy birch extends farther north into the Arctic than any other broadleaf tree. Specimens of the subarctic populations are usually small and very contorted, and are often distinguished as arctic downy birch or mountain birch, B. p. var. pumila.[7][8] (not to be confused with B. nana). This variety is notable as being one of very few trees native to Iceland and Greenland, and is the only tree to form woodland in Iceland. At one time the island is thought to have been covered in downy birch woodland, but that cover is reduced to about one percent of the land surface today.[4]

Varieties and cultivars[edit]

Arctic downy birch forms the treeline in most of Scandinavia
Three varieties are recognised, the nominate Betula pubescens var. pubescensB. p. var. litwinowii (distributed in the Caucasus and Turkey) and B. p. var. pumila (arctic downy birch or mountain birch, formerly called B. p. subsp. tortuosa).[9] The latter has arisen from the hybridization of var. pubescens and B. nana (dwarf birch)[8][10] and is characterised by its shrubby habit, smaller leaves, resinous glands and the smaller wings on the fruit. A number of cultivars have been grown but many are no longer in cultivation. They include "Armenian gold", "Arnold Brembo" (scented foliage), crenata nana (shrubby and dwarf), incisa (lobed foliage), integrifolia (unlobed foliage), murigthii (shrubby with doubly serrate leaves), ponitica (hairless), undulata (leaf margins waxy), urticifolia (nettle-leaved), variegata (variegated) and "Yellow wings".[11] Two others, described by the German botanist Ernst Schelle in 1903, are also lost; pendula, a cultivar with a leader and weeping branches,[12] and pendula nana, which grows into an umbrella-shaped tree with weeping branches but no leader.[12]

Ecology[edit]

The larva of the autumnal moth (Epirrita autumnata) feeds on the foliage of Betula pubescens and other tree species. In outbreak years, large areas of birch forest can be defoliated by this insect. Damage to the leaf tissue stimulates the tree to produce chemicals that reduce foliage quality, retarding the growth of the larvae and reducing their pupal weights.[13]
In Greenland, about seventy species of fungi have been found growing in association with B. pubescens, as parasites or saprobes on living or dead wood. Some of the most common fungi include Ceriporia reticulataChondrostereum purpureumExidia repandaHyphoderma spp, Inonotus obliquusInonotus radiatusMycena galericulataMycena rubromarginataPanellus ringensPeniophora incarnataPhellinus lundelliiRadulomyces confluensStereum rugosumTrechispora spp., Tubulicrinis spp. and Tyromyces chioneus.[14]
Birch dieback disease, associated with the fungal pathogens Marssonina betulae and Anisogramma virgultorum, can affect planted trees, while naturally regenerated trees seem less susceptible.[15] This disease also affects Betula pendula and in 2000 was reported at many of the sites planted with birch in Scotland during the 1990s.[16]

Uses[edit]

Betula pubescens is a pioneering species, seen expanding its range here in Norway
The outer layer of bark can be stripped off the tree without killing it and can be used to make canoe skins, drinking vessels and roofing tiles.[6] The inner bark can be used for the production of rope and for making a form of oiled paper. This bark is also rich in tannin and has been used as a brown dye and as a preservative. The bark can also be turned into a high quality charcoal favoured by artists. The twigs and young branches are very flexible and make good whisks and brooms.[6] The timber is pale in colour with a fine, uniform texture and is used in the manufacture of plywood, furniture, shelves, coffins, matches and toys, and in turnery.[17]
The Sami people of Scandinavia used the bark of both B. pubescens and B. pendula as an ingredient in bread-making; the reddish phloem, just below the outer bark, was dried, ground up and blended with wheat flour to make a traditional loaf.[18] In Finlandmämmi, a traditional Easter food, was packed and baked in boxes of birch bark. Nowadays, cardboard boxes are used, but imprinted with the typical bark pattern.[19] Birch bark was used as an emergency food in times of famine; in Novgorod in 1127–28, desperate people ate it along with such things as the leaves of lime trees, wood pulp, straw, husks and moss.[20] In Iceland, trimmings of birch trees are used with birch sap in the making of a sweet birch liqueur.[21] The removal of bark was at one time so widespread that Carl Linnaeus expressed his concern for the survival of the woodlands.[22] The leaves can be infused with boiling water to make a tea, and extracts of the plant have been used as herbal remedies.[2]
Both B. pubescens and B. pendula can be tapped in spring to obtain a sugary fluid. This can be consumed fresh, concentrated into a syrup similar to the better-known maple syrup, or can be fermented into an ale or wine. In Scandinavia, this is done on a domestic scale, but in the former USSR, particularly Russia, Ukraine, Belarus, Estonia, Latvia and Lithuania, birch sap is harvested commercially and used to manufacture cosmetics, medicines and foodstuffs.[23]