SWEET potatoes may provide the next novel drugs for cancer and diabetes. Recent study by Japanese researchers published in Journal of Agriculture, Food and Chemistry indicates that the growth of human cancer cells can be successfully suppressed with sweet potato extracts.
A previous study had demonstrated that the phytochemicals in sweet potato have significant antioxidant and anticancer activities. The antioxidant activity was directly related to the total amount of phenolics and flavonoids in the extracts. Researchers suggest that the additive roles of phytochemicals may contribute to its ability in inhibiting tumor cell proliferation in vitro.
Also, researchers from Austria, Italy and Switzerland have demonstrated the tolerability, efficacy, and mode of action an extract of white sweet potatoes on metabolic control in type 2 diabetic patients.
The researchers suggest that despite its "sweet" name, sweet potato may stabilize blood sugars and lower insulin resistance. Other studies have shown that the flavone extracted from sweet potato leaf could control blood sugar and modulate the metabolism of glucose and blood lipid, and decrease outputs of lipid peroxidation and scavenge the free radicals in non-insulin dependent diabetic rats.
India researchers have demonstrated the cyhoneypotxic and antioxidant activities of sweet potato. The study published in the International Journal of Pharmacy and Pharmaceutical Sciences concluded: "On the basis of the above results it can be concluded that he ethanolic extract possess significant anticancer and antioxidant activities studied by in vitro models. The presence of flavonoids and related phyto-constituents may be responsible for the activity. Further investigations are required to find active component of the extract and to confirm the mechanism of action. Further studies warranted, for isolation of the constituents responsible for the activity and also to explore the exact mechanism of action of the activity."
Commonly called sweet potato, Ipomoea batatas belongs to the plant family Convolvulaceae. In Nigeria, it is called edia-makara in Anaang, dankai in Berom, iyan-ebo in Edo, bia mbakara in Efik, ba-fadamee in Hausa, ediam-umani in Ibibio, ji-bekee or nduku in Ibo, beke buru in Ijo-Izon, dangali in Kanuri, dangura in Mambila, duku in Nupe, atsaka in Tiv, imitata or ole-oyinbo in Urhobo, anamo or odukun in Yoruba.
According to the Useful Plants of West Tropical Africa by H. M. Burkill, the tubers have been used for distillation to 'tumbo spirit' in Nigeria. Vitamins are well represented, particularly the yellow-fleshed cultivars. The plant is usually a three to four months crop, but some cultivars run to six months. Little medicinal use is made of the tubers. They are used in frictions on the skin in Cote D'Ivoire to prevent loss of pigmentation. A purgative tisane is made from the root with leaves of Cassia occidentalis (Leguminosae: Caesalpinioideae) and the bark of Bridelia ferruginea (Euphorbiaceae) in Congo.
Bactericidal and fungicidal substances have been isolated from the tuber and the haulm. The young leaves are commonly eaten by man, and leafy stems are fed to stock. They are a good source of vitamins and minerals especially calcium and especially in the purple-leafed forms. They are anti-diabetic and anti-scorbutic.
In Senegal poultices for abscesses are made of the leaves. The leaf-sap is used on burns in Cote D'Ivoire, the pounded leaves are made into an enema given to avert miscarriage, and leaves are applied in topical frictions to relieve intercostal pain and in mouth-wash and gum-massage for toothache. Toxic substances have been reported and excessive ingestion is known to cause diarrhoea, and even death. Some alkaloid has been recorded in the stems and leaves and in the roots.
The Japanese study is titled "Growth suppression of human cancer cells by polyphenolics from sweet potato (Ipomoea batatas L.) leaves."
R. Kurata, M. Adachi, O. Yamakawa, and M. Yoshimoto of the Department of Upland Farming Research, National Agricultural Research Center for Kyushu Okinawa Region, Yokoichi, Miyakonojo, Miyazaki, Japan found that sweet potato leaves (Ipomoea batatas L.) contain a high content of polyphenolics that consist of caffeic acid, chlorogenic acid, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid, and 3,4,5-tri-O-caffeoylquinic acid.
They wrote: "We investigated the suppression of the proliferation of selected human cancer cells by phenolic compounds isolated from sweet potato leaf. The human cancer cells used in this research included a stomach cancer (Kato III), a colon cancer (DLD-1), and a promyelocytic leukemia cell (HL-60). Caffeic acid and di- and tricaffeoylquinic acids dose-dependently depressed cancer cell proliferation, and the difference in sensitivity between caffeoylquinic acid derivatives and each kind of cancer cell was observed.
"Specifically, 3,4,5-tri-O-caffeoylquinic acid effectively depressed the growth of three kinds of cancer cells, and caffeic acid had an exceptionally higher effect against HL-60 cells than other di- and tricaffeoylquinic acids. In attempting to clarify the mechanism of growth suppression with the addition of the apoptotic inhibitor N-ethylmaleimide, we observed that the nuclear granulation in 3,4,5-tri-O-caffeoylquinic acid-treated HL-60 cells suggested apoptosis induction. This effect was confirmed by DNA fragmentation, an increase of caspase-3 activity, and expression of c-Jun. Growth suppression of HL-60 cells by 3,4,5-tri-O-caffeoylquinic acid was determined to be the result of apoptotic death of the cells. These results indicate that 3,4,5-tri-O-caffeoylquinic acid may have potential for cancer prevention."
According to the study by Bernhard Ludvik of the Department of Medicine III, Division of Endocrinology and Metabolism, University of Vienna, Vienna, Austria; Beatrice Neuffer of Via Livio 14, Chiasso, Switzerland; and Giovanni Pacini of the Metabolic Unit, Institute of Biomedical Engineering, ISIB, National Research Council, CNR, Padova, Italy, a total of 61 type 2 diabetic patients treated by diet were given 4 gram of extracts of white sweet potato called Caiapo once daily for 12 weeks. Each subject underwent a 75-g oral glucose tolerance test (OGTT) at baseline and after one, two, and three months to assess two-hour glucose levels. Additionally, fasting blood glucose, HbA1c, total cholesterol, and triglyceride levels were measured.
After treatment with Caiapo, HbA1c decreased significantly, whereas it remained unchanged in subjects given placebo. Fasting blood glucose levels decreased in the Caiapo group and did not change in the placebo group. A decrease in body weight was observed in both the placebo group and in the Caiapo group, probably due to a better- controlled lifestyle. In the Caiapo group, body weight was related to the improvement in glucose control. Two-hour glucose levels were significantly decreased in the Caiapo group compared with the placebo group. Mean cholesterol at the end of the treatment was significantly lower in the Caiapo group than in the placebo group. No significant changes in triglyceride levels or blood pressure were observed, and Caiapo was well tolerated without significant adverse effects.
The researchers concluded: "This study confirms the beneficial effects of Caiapo on plasma glucose as well as cholesterol levels in patients with type 2 diabetes. For the first time, the long-term efficacy of Caiapo on glucose control was demonstrated by the observed decrease in HbA1c. Thus, the neutraceutical Caiapo seems to be a useful agent in the treatment of type 2 diabetes."
Phytochemical analysis sweet potato leaves showed that they are very nutritious when compared to vegetables such as cassava leaves, amaranth, mushrooms, taro, and pumpkin leaves. Sweet potatoes are reportedly good source of vitamins A, B and C, iron, calcium and phosphorus.
High in complex carbohydrates and dietary fibre; deficient in protein.
An invention made from the extracts of leaf and stems of sweet potato has been shown to have qi and spleen invigorating effects, cooling the blood and stopping bleeding. Such a composition has the potential of use for ITP (idiopathic thrombocytopenic purpura), radiotherapy- and chemotherapy-induced thrombocytopenia.
A 2006 study of commonly consumed roots crops in the Philippines (Kamote, Ipomoea batata; ubi, purple yam, Dioscorea alata; cassava, Manihot esculenta; taro or gabi, Colocasia esculenta; carrot, Daucus carota; yacon (Smallanthus sonchifolius) showed them to be rich sources of phenolic compounds with antioxidant acitivity, highest in sweet potato, followed by taro, potato, purple yam and lowest in the carrot
Other results suggest the total phenolic content was positively correlated with radical scavenging activities of the sweet potato leaves. Purple sweet potato anthocyanins have antioxidative activity in vivo as well as in vitro.
Another study has identified new chitinolytic enzymes in sweet potato leaves. Chitinases catalyze the hydrolysis of chitin, the main structural component of fungal walls and arthropod integuments. Studies suggest it has other functions and has been proposed to play a role in the defense against pathogens. Chitinases are also useful in the production of biomedical and biotech products; used in the production of chitooligosaccharides, glucosamines and GlcNAc. Other applications are found in mosquito control and pathogenic plant fungi control.
| Posted: at | |
harold634
mcena
TRENDING GISTS 
Teacher Arrested For Rap!ng 16yr Old Students in His Care in Kwara State
PHOTOS: Olisa Metuh, Others Celebrate Ike Ekweremadu's 62nd Birthday While in UK Prison
Tottenham v Manchester City: English Premier League Match,Team News,Goal Scorers and Stats
Why Men Should Take Their Wives’ Last Names - Lady Sparks Reactions After Stating Her Reason
Tragedy As Generator Fumes Kill Woman & Son In Delta
Edo State Govt Takes Custody Of 4Yr Old Girl Used For Adult Content By Her Father
VIDEO: Mob Apprehend Man Who Was Caught Trying to Detonate a Bomb at a Bank in Jos