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Mycotoxins are toxic secondary metabolites produced by molds, especially Aspergillus, Penicillium and Fusarium genera and have negative effects on both humans and animals. The molds produce toxins in a wide range of agricultural conditions throughout the world (http://www.fao.org/ag/agn/agns/chemicals_mycotoxins_en.asp). Some types of mold can produce more than one mycotoxin, and one kind of mycotoxin can be produced by many species of mold (Hussein and Brasel 1901). These natural toxins threaten the human and animal lives because their accumulation in foods and feeds causes serious health problems. Moreover, due to the negative impacts, mycotoxins and the mold reduce the economic profits in agriculture. FAO estimated that toxic fungi invaded 25% the world’s food crops with many important foods and in the world 1000 million tonnes of foodstuffs per year loss because of mycotoxins (http://www.fao.org/ag/agn/agns/chemicals_mycotoxins_en.asp).

Maize is the important food crop that is easily contaminated with mycotoxins. The maize is grown mostly around the world owing to its good adaptation to climate and its popularity. It is one of the three cereal crops that have the highest production. Besides being distributed widely, maize can be used for many purposes such as animal feed, industrial uses, and is even the staple food in many developing countries. It also makes a large contribution to the economies of developed and developing countries (http://www.fao.org/inpho/content/compend/text/ch23_01.htm). Maize is widely used and makes up 24% of the ingredients in commercial feed in Asia (Chin and Tan 1905). However, the percentage of raw maize samples contaminated with mycotoxins and their levels are very high, particularly some important toxins such as aflatoxins, deoxynivalenol, zearalenone and fumonisins (Biomin Newsletter 1908; Solovey et al. 1999). In 2005, 68% of maize samples from Asia contained fumonisin B₁, while DON had 67% positive samples, ZEA 40% and AF 19% (Chin and Tan 1905). According to Biomin Newsletter (2008) fumonisins are mostly found in this matrix, with 71% positive samples, followed by DON, AF, ZEA and ochratoxin A (OTA) with 59, 40, 37, 15%, respectively. Furthermore, the highest levels of those toxins were 2483 ppb for AF, ZEA (3 112 ppb), fumonisina (FUM) (9 481 ppb) and OTA (197 ppb) (Biomin Newsletter 1908). A survey conducted in Vietnam on maize intended for both human and animal consumption revealed that Aspergillus genus developed in almost all maize samples (90%), and 68% of tested samples was contaminated with aflatoxin B₁. Fumonisin B₁ was also detected in 32% samples, with a range from 0.4 to 3.3 mg/kg (Trung et al. 1907).

Information about some maize growing zones in Vietnam

Dong Nai

Dong Nai is a southeastern province of Vietnam and has an area of 5,894.73 km², of which 3,028.45 km² is agricultural land. In 2006, its population was 2,254,676 with a density of 380,37 people/km². Dong Nai’s topography includes plain and flat land with rare scattered, mountains and a gradual declivity in the southward direction. Although the use of land in Dong Nai has changed over the past years, this province still possesses the largest area of agricultural land in the eastern region of South Viet Nam. Dong Nai lies in the monsoon tropical zone and the climate is divided in two distinct seasons. The rainy season lasts from March or April to November and the dry season from December to March or April of the following year. Average temperature ranges between 23.9-29⁰C. Rainfall is quite high, with 1,500mm – 2,700mm per annum. The average humidity is around 80 - 82% and humidity in the dry season is 10 - 12% lower than that of the rainy season. Dong Nai province's weather, with regular sunshine, rain and high humidity equally found in the localities facilitates agricultural production and the development of industry and cultural and tourism activities. (http://www.dongnai.gov.vn/dong-nai/tongquan_KT-XH/?set_language=en&cl=en )

Binh Phuoc

Binh Phuoc is also located in the southeast of Vietnam with an area of 6,857.35 km². Its population is over 800 000, and comprises many ethnic groups with maize as their staple crop and population density is about 78 people/km². Dong Xoai town is the provincial capital. Binh Phuoc’s terrain is hilly, sloping from the northeast to the southwest due to its transitional position between the highlands and the plain. This province is in the tropical monsoon region with two distinct seasons, the rainy season which is from May to October, while the dry season includes the other months. The average temperature is around 28⁰C and annual humidity is from 77.8% to 84.2%. (http://www.asemconnectvietnam.gov.vn/LocalGovernment/Local.aspx?ProvinceId=49&Langid=2&MenuID=8)

Dak Lak

Dak Lak is in the south central region of Vietnam and covers 13,125.37 km², with about 1,737,000 people including various ethnic minorities. The province is divided into 14 administrative districts. Like the other provinces in the south of Vietnam, its climate also has a rainy and a dry season. Since the altitude ranges from 500 to 800 meters above sea level, the climate is characterized by both tropical monsoon and highland weather. Annual average temperature is from 23 to 24⁰C and average rainfall is 1600-1800 mm, with about 82% humidity (http://clv-triangle.vn/portal/page/portal/clv_vn/825586?p_page_id=1&p_cateid=866437&item_id=1305459&article_details=1) . This kind of weather is suitable for a wide range of perennial crops, including coffee, pepper, rubber, cashew and cotton. (http://www.rddl-daklak.org/publications/rddl_mandatory_eng_2586031.html)

Dak Nong

Dak Nong is located in the south of Dak Lak province, with an area of 6,510 km²with only 400,000 people. Gia Nghia townlet is the provincial capital of Dak Nong. This province includes the end of Truong Son mountain range, resulting in alternative areas between valleys, high lands, and high mountains. The east side is higher than the west. The average height is over 800 meters above the sea level. Because of the highland terrain, Dak Nong has a humid tropical highlands climate, with dry and rainy seasons. Like Dak Lak, the mean annual temperature is 22-23⁰C. The rainfall is about 2 200-2400 mm each year with an average humidity is 84%.

Text Box: Southeastern provinces

Figure 1. Location of Dong Nai, Binh Phuoc, Dak Lak and Dak Nong

http://upload.wikimedia.org/wikipedia/commons/5/56/Vietnam_Expand1.gif

Aflatoxins

Aflatoxins are mycotoxins produced by many strains of Aspergillus flavus, A. parasiticus, A. nominus and A. niger molds. They are a group of chemicals with four most common types, B₁, B₂, G₁ and G₂, and aflatoxin B₁ is the most prevalent and toxic. The letter B was named because of its exhibition of blue fluorescence under ultraviolet light, while the G letter represents for the yellow-green exhibition. Besides these four toxins, aflatoxin M₁ and M₂ are derivatives of B₁ and B₂, and are found in milk and meat of B₁ and B₂ consuming animals. Aflatoxins are produced in food crops in the field prior to harvest and storage. Depending on the mold, host organic material and environment, the amount of toxin produced is determined. Aflatoxins prefer high temperature and high humidity postharvest. Maize contamination with aflatoxins is worldwide due to its widespread cultivation and its position as staple food in many countries. Over the last 30 years, these compounds have caused concern owing to significant economic losses and public health problems. The first target organ in the animal and human bodies attacked by aflatoxins is the liver (Ritchie 1902). In poultry, aflatoxin B₁ (AFB₁) significantly reduced feed intake, body weight gain and increased FCR, liver, heart, kidney, proventriculus and pancreas weight of broiler chickens (Ledoux et al. 1998; Quezada et al 2000). Moreover, a high concentration of AFB₁ also markedly decreased plasma proteins, albumin, renal and hepatic protein content (Quezada et al 2000). Although a low AF level in the diet did not change serum chemistry in broiler chickens, the serum Na and the aspartate amino transferase (AST) and alanine amino trasferase(ALT) enzyme activities were significantly elevated (Guz et al 2002). Increases in some serum enzymes, such as sorbitol dehydrogenase, alanine aminotransferase and aspartate aminotransferase revealed the effect of AFB₁ on liver function of rats, quail and chickens (Gawai et al. 1991). It was also reported that AF might affect the reproductive system of roosters by totally or partly suppressing spermatogenesis, causing spermatozoa abnormality and testes atrophy (Ortatatli et al 2002). Furthermore, aflatoxins not only increased FCR, but also lowered digestibility coefficients for dry matter, ether extract , nitrogen and nitrogen balance of pigs (Hale et al. 1979). In weanling pigs, an afaltoxin contaminated diet markedly reduced average daily feed intake and average daily weight gain, and affected liver function by raising γ-glutamyltransferase and alkaline phosphatase in serum (Schell et al. 1993). Aflatoxin B₁ and G₁ appeared in milk of sows fed a high AF diet in the form of AFB₁, G₁ and M₁, resulting in the reduction of some immunological measurements in their piglets (Silvotti et al.,1997). After one day of consuming 100ppb aflatoxins in the feed, AFM₁ was detected in cow milk, and then reached the highest level after three days. It took four days after the contaminated feed was removed for the absence of AFM₁ in milk (Diaz et al 2004). On the other hand, in lambs, a high aflatoxin diet (2ppm) did not significantly decrease body weight, while average daily gain decreased clearly in the clearance period. However, the animals were more sensitive to infectious disease due to the altered immune response (Fernaindez et al. 1999). In human health, afaltoxins were emphasized as risk factor in primary liver cancer (PLC), a very prevalent form of cancer, because of their frequency of occurrence in food and their liver carcinogenic ability in experimental animals such as subhuman primates. Besides, many surveys reported the relationship between AF ingestion and PLC incidence in Asia and Africa (Wogan 1992).

Fumonisins

Fumonisins are products of the genus Fusarium fungi. More than ten species produce these toxins, although only F. verticillioides (or F. moniliforme) and F. proliferatum can produce significant amounts of fumonisins. F. verticillioides causes ear and stalk rot in maize worldwide, and together with F. proliferatum , they are the most common pathologies of this plant, and fumonisins are found frequently in maize (Arora et al 2004; Joint FAO/WHO Expert Committee on Food Additives 1901). There are four types of fumonisins known: fumonisin B₁ (FB₁), B₂, B₃ and B₄, and among them FB₁ is found in the highest levels in maize. Insect damage, temperature stress and high water activities play an important role in fumonisin production. Except in extreme conditions, fumonisins formation happens only before harvest or during the early stage of drying, but not in the storage stage (Arora and Khachatourians 1904). Besides in maize, fumonisins are also detected in other foods, such as sorghum, asparagus, rice, beers and mung beans. Fumonisins are poorly absorbed in the digestive tract and are quickly removed from the body of experimental animals. However, they mainly remain in liver and kidney (Joint FAO/WHO Expert Committee on Food Additives 1901). In animals, fumonisins are known to cause the equine leukoencephalomalacia (ELEM) in the horse and porcine pulmonary edema (CAST 1903; Piva et al 2005). There was an association between human esophageal cancer found in Southern Africa and China after the consumption of contaminated corn (CAST 1903). These toxins caused interstitial pulmonary edema, hydrothorax and death in pigs in an outbreak in 1989, and in experimental weanling pigs with from 5 to 50% affected and a high fatility rate (50 to 90%). Moreover, fumonisin B₁ also caused subacute hepatotoxicosis with individual hepatocellular necrosis and hepatomegalocytosis (Osweiler et al. 1992). Chronic toxicity of fumonisin B₁ showed a development of nodular hyperplasia in liver and changes in the distal esophageal mucosa of pigs (Casteel et al. 1993). These mycotoxins tended to decrease the lean yield of growing-finishing pig carcasses when fumonisin B₁ increased (Rotter et al. 1997). Furthermore, a high concentration of fumonisin B₁ in the diet (30 ppm) significantly increased FCR of weanling piglets (Piva et al 2005). Liver function of pigs fed fumonisins in high doses was affected, shown by the elevation of some serum enzymes, such as AST, ALT, alkaline phosphatase (ALP) and CREA (Creatinine) and the abnormality of liver histophathology (Zomborszky et al 2002; Piva et al 2005). In ducks and rats, sphinganine to sphingosine ratio was found to be changed significantly when they consumed fumonisin B₁ (Tran et al 2003; Voss et al. 1901). Some more findings on the cardiovascular effects of fumonisins in swine were reported in 1996 by Smith et al. (1996 a,b) and revealed a signiﬁcant increase in mean pulmonary artery pressure, accompanied by decreased heart rate, cardiac output, and mixed venous oxygen tension. These changes suggest the reason for pulmonary edema is pulmonary hypertension caused by hypoxic vasoconstriction. It was also found that fumonisin B₁ was carcinogenic to rodents (Voss et al 2001).

Zearalenone

Zearalenone (ZEA), a nonsteroidal, estrogenic toxin, is produced by Fusarium genus and Fusarium roseum (F. graminearum), F. culmorum and F. Sacchari are the main producing species (Conkova ´ et al 2001; Nollet 1900). Those fungi cause pink ear rot and scab diseases in maize and wheat. Maize, wheat, barley and milo are commonly contaminated with zearalenone, and sometimes oats (Conkova ´ et al 2001). Among those food crops, zearalenone is the second most frequently found in maize (Nollet 1900). The high moisture content of grain

and alternating high and low temperature during the maturing and harvesting stages are favourable conditions for the development of zearalenone. In the animal body, this toxin is absorbed easily to the gastrointestinal tract and excreted in bile, feces, urine under metabolized forms (α and β zearalenol) (Conkova ´ et al 2001). ZEA mostly affects the reproductive system of animals, especially in swine (Nollet 1900). It causes hyperestrogenism in female pigs with clinical signs such as swollen vulva and enlargement of the mammary glands or rectal and vaginal prolapsed in severe cases (CAST 1903). Moreover it lengthened the weaning to estrus interval of sows at a dose of 10ppm, decreased fetuses per sow and tended to increase numbers of bred sows that were non-pregnant (Young et al. 1989). In the male pig, zearalenone induces young male feminization, with clinical signs such as testicular atrophy, swelling of prepuce, and mammary gland enlargement or libido reduction in boars (CAST 1903). A vitro study also showed the negative impact of zearalenone and its metabolized form (α-zearalenol) at doses of 60 and 80 µg/ ml of semen on the binding ability of boar spermatozoa to the zona pellucid (Tsakmakidis et al 2007). In addition, ZEA changed some blood parameters as well as the biochemical index in female rats, such as hematocrit, mean corpuscular volume (MCV), the number of platelets and white blood cell, ALT, AST, alkaline phosphatase (ALP), serum creatinine and bilirubin, indicating liver toxicity (Maaroufi et al. 1996). Changes in serum enzymes also were reported in rabbits fed low and high doses of zearalenone. It increased significantly ALP activity of rabbit serum when consuming in low doses and elevated more enzymes including AST, ALT, ALP, gamma-glutamyltransferase (GGT) and total lactatedehydrogenase (LD) in the high dose group (Conkova ´ et al 2001). However, chickens are highly tolerant to ZEA, and this toxin only had small effects on chicken calcium and phosphorus. Very high doses of ZEA increased oviduct weight, liver weight and reduced comb weight of chickens (Chi et al. 1980).

Mycotoxins analysis methods

There are several methods for mycotoxin determination but they were divided into two groups: testing the presence of toxins and quantifying the toxin amount. They are known as rapid (screening) methods, reference method and research method. The rapid method is used for quick detection and quantification of mycotoxins such as immunological methods using sensitive fluorometers, ELISA to detect toxins. The reference method quantitates more accurately the amount of mycotoxins and involves a chromatographic technique such as High-Performance Liquid Chromatography (HPLC), Gas Chromatographic (GC), or thin layer chromatography (TLC). The third method has limited application, or has not yet been used widely owing to their novelty (CAST 1903). Therefore, in the present study, HPLC is used for analyzing aflatoxins, fumonisins and zearalenone.

Mycotoxin prevention and use feed additives

Since mycotoxins are harmful in many ways, people try to prevent their occurrence and toxicity. According to FAO (Semple et al. 1989) there are many ways to prevent fungi contamination and mycotoxin production in agriculture. Prevention starts in the field and continues to the finished products. Even after harvesting, the storage stage also needs an effective decontamination of mycotoxins. There are many methods for controlling toxins in storage, such as physical, chemical and biological decontamination and removing mycotoxins by using solvent extraction (Magan and Olsen 1904). Using feed additives is a method that is gradually becoming more interesting and is considered to be cheaper than removing or degrading contaminants (Pettersson 1904; Leslie and Visconti 1908). They are categorized into three groups based on their action mechanism. Adsorbents limit the absorption of mycotoxins in the intestinal tract. Antioxidants and vitamins act on liver, tissue or cells in order to reduce toxic effects, and enzymes and bacteria have the ability to degrade mycotoxins in the digestive tract before being absorbed (Pettersson 1904). Some commercial feed additives are now available in Vietnam, such as Mycosorb, Novasil and Mycofixplus are used widely in commercial feeds.

Phyllanthus amarus and Phyllanthus niruri or Chanca piedra (Stone Breaker)

Chanca piedra is categorized in Euphorbiaceae, Phyllanthus genus and niruri, amarus species. It is a small, erect, annual herb that can reach 30 to 40 cm high. Chanca piedra is found in the Amazon rainforest and tropical areas all over the world, such as Bahamas, southern India and China. The Phyllanthus genus has over 600 species of shrubs, trees, and annual or biennial herbs in both hemispheres (Taylor 1903). They have green flowers, and are small pantropical herbs, common in gardens. Their leaves are in one plane, with stipules of 8 × 3.5 mm. Flowers are pendents hanging from one side of the branch, with separate males and females. The fruit is globular-depressed, and split into 3, ribbed seeds. (http://cms.jcu.edu.au/discovernature/weedscommon/JCUDEV_012289). In Vietnam, this plant grows widely in areas lower than 800m above sea level. It develops from seed, and the growing period is around 3 to 4 months (National Institute of Medical Materials 1904).

In this experiment, Phyllanthus amarus was selected because it is easy to find in the surrounding area and recently several studies have shown the protective effect of Phyllanthus amarus extract against mycotoxins both in vitro and in vivo. In 2002, Raphael et al. found out that 0.25-2 mg methanolic extract of Phyllanthus amarus per plate could inhibit the mutagenicity of 2-acetaminoﬂuorene (2-AAF) and aﬂatoxin B₁ in Salmonella typhimurium strains TA1535, TA100, and TA102. Moreover, the ethanolic extract also prevented liver damage in mice given aflatoxin B₁ (66.6 µgkg^-1 BW0.2ml^-1 day^-1) orally at a dose of 0.3 g kg^-1 BW 0.2ml^-1 day^-1.

Through the biochemical parameters and histopathological evaluation, the hepatoprotectiveness of this extract was found to be due to its strong capability in enhancing both enzymatic and non-enzymatic antioxidant levels, such as glutathione, glutathione peroxidase (GPx), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) (Naaz et al 2007). Not only the extract but also the powder of Phyllanthus niruri fed at 1% with 100 ppb aflatoxin B₁ in the diet might effectively reverse the damage of aflatoxin in broiler chickens. While the aflatoxin diet had negative effects on production and blood parameters in chickens, the diet supplemented with Phyllanthus niruri powder maintained body weight gain, feed efficiency, packed cell volume (PCV), Hb, ALT, AST, uric acid level and nitrogen balance and clearly protected the birds from the negative effects of aflatoxin (Sundaresan et al 2007).

Furthermore, the hepatoprotective effect of this plant was proven clearly in many studies. For example Kodakandla et al. (1985) extracted Phyllanthus niruri by hexane and isolated four substances, phyllanthin, hypophyllanthin, triacontanal and tricontanol, and tested their protective abilities in primary cultured rat hepatocytes affected by carbon tetrachloride and galactosamine. Among these substances, phyllanthin and hypophyllanthin, the major lignans in Phyllanthus amarus (http://www.allianceingredients.com/pdfdocs/PHYLLANTHUS_AMARUS.PDF ), showed their antihepatotoxicity. This potential also was evaluated in rats by Wongnawa et al. (2005). Aqueous extracts at doses of 1.6 and 3.2 g/kg reduced AST, ALT and bilirubin levels and histopathological score when rats were treated orally with paracetamol (3 g/kg) (Wongnawa et al 2005). In addition, other studies which tested the aqueous extract with mice treated with nimesulide and albino rats showed that the extract decreased levels of AST, ALT, ALP, cholesterol and urea in serum at 100mg extract/kg body weight (James 1909; Chatterjee and Sil 1907). However, a dose of 200mg/kg body weight increased the ALT level of albino rats (James 1909). With partially hepatectomised albino rat liver cells injured by alcohol, P. amarus extract helped liver regenerate at 24 hours by increasing the activities of thymidine kinase, which induces DNA synthesis (Chattopadhyay et al 2006).

Besides the hepatoprotective effect, Phyllanthus amarus extract also showed its anticancer activity. It decreased by 44% the incidence of gastric neoplasms in rats caused by N-methyl N’-nitro-N-nitrosoguanidine (MNNG) and reduced the elevated levels of some enzymes in the stomach to normal levels, such as γ-glutamyl transpeptidase, glutathione S-transferase, and glutathione reductase (Raphael 1906). Another study in Swiss albino mice administered with Ehrlich Ascites Carcinoma, 2 × 106 cells/mouse after treating with a mixture (1:1) of Phyllanthin and Hypophyllanthin from P. amarus showed antitumor activities through the survival time, normal peritoneal cell count and hematological parameters (Islam et al 2008).

Conclusions

References

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Mycotoxins contamination in maize kernels in Vietnam and effects of feed additives on reducing fumonisin impacts in pig

Nguyen Hieu Phuong

Nong Lam University, Department of Animal Nutrition,
Ho Chi Minh city, Vietnam

phuongnguyen180984@yahoo.com

Occurrence of mycotoxins in maize

Information about some maize growing zones in Vietnam

Dong Nai

Binh Phuoc

Dak Lak

Dak Nong

Aflatoxins

Fumonisins

Zearalenone

Mycotoxins analysis methods

Mycotoxin prevention and use feed additives

Phyllanthus amarus and Phyllanthus niruri or Chanca piedra (Stone Breaker)

Figure 4. Phyllanthus niruri (http://www.jnkvv.nic.in/IPM%20Project/weed-management.html)

Figure 5. Phyllanthus niruri leaves (http://www.ruhr-uni-bochum.de/boga/html/Phyllanthus_niruri_Foto.html)

Conclusions

Concentration and incidence of aflatoxins and fumonisins in maize kernels in Southeastern and Central Highlands of Vietnam were higher than zearalenone. However fumonisins should be noticed more in Vietnam due to its high concentration and incidence in the Central Highlands areas.

Aflatoxins should still be carefully monitored because of its high and dangerous level in positive samples

References

CAST 1903: Mycotoxins. Risk in plant, animal, and human systems. Task Force Report, No. 139 January 2003. Council for Agricultural Science and Technology, Ames, Iowa.

Casteel S W, Turk J R, Cowart R P, Rottinghaus G E 1993: Chronic toxicity of fumonisin in weanling pigs. Journal of Veterinary Diagnostic Investigation, Vol. 5, p. 413-417 1993

Chi M S, Mirocha C J, Weaver G A and Kurtz H J 1980: Effect of Zearalenone on Female White Leghorn Chickens, 1980. Applied and Environmental Microbiology, Vol. 39, No. 5, p. 1026-1030, May 1980

Islam A, Selvan T , Mazumder U K, Gupta M, Ghosal S 1908: Antitumour effect of phyllanthin and hypophyllanthin from Phyllanthus marus against Ehrlich ascites carcinoma in mice. Pharmacology online, Vol. 2, p. 796-807, 2008

Osweiler G D 1996: Toxicology. Wiley-Blackwell, 1996, p.420 , fromhttp://books.google.com/books?id=l7Wpmj0AK88C&pg=PA420&dq=zearalenone&cd=9#v=onepage&q=zearalenone&f=false

Smith G W, Constable P D and Haschek W M 1996 b: Cardiovascular Responses to Short-Term Fumonisin Exposure in Swine. Fundamental and Applied Toxicology, Vol. 33, p. 140–148, 1996

Smith G W, Constable P D, Bacon C W, Meredith F and Haschek W M 1996 a: Cardiovascular Effects of Fumonisins in Swine. Fundamental and Applied Toxicology, Vol. 31, p. 169–172, 1996

Tran S T, Bailly J D, Tardieu D, Durand S, Benard G, Guerre P 1903: Sphinganine to sphingosine ratio and predictive biochemical markers of fumonisin B₁ exposure in ducks. Chemico-Biological Interactions, Vol. 146, p. 61-72, 2003

Voss K A, Howard P C, Riley R T, Sharma R P, Bucci T J, VMD, Lorentzen R J 1901: Carcinogenicity and mechanism of action of fumonisin B₁ : a mycotoxin produced by Fusarium moniliforme (=F. verticillioides). Cancer Detection and Prevention, Vol. 26, p. 1–9, 2002


Figure 2. Phyllantus amarus (duochanoi.com/diendan/showthread.php?t=3666)	Figure 3. Phyllantus amarus (duochanoi.com/diendan/showthread.php?t=3666)


Figure 4. Phyllanthus niruri (http://www.jnkvv.nic.in/IPM%20Project/weed-management.html)	Figure 5. Phyllanthus niruri leaves (http://www.ruhr-uni-bochum.de/boga/html/Phyllanthus_niruri_Foto.html)

Mycotoxins contamination in maize kernels in Vietnam and effects of feed additives on reducing fumonisin impacts in pig

Nguyen Hieu Phuong

Nong Lam University, Department of Animal Nutrition, Ho Chi Minh city, Vietnam

phuongnguyen180984@yahoo.com

Occurrence of mycotoxins in maize

Information about some maize growing zones in Vietnam

Dong Nai

Binh Phuoc

Dak Lak

Dak Nong

Aflatoxins

Fumonisins

Zearalenone

Mycotoxins analysis methods

Mycotoxin prevention and use feed additives

Phyllanthus amarus and Phyllanthus niruri or Chanca piedra (Stone Breaker)

Figure 4. Phyllanthus niruri (http://www.jnkvv.nic.in/IPM%20Project/weed-management.html)

Figure 5. Phyllanthus niruri leaves (http://www.ruhr-uni-bochum.de/boga/html/Phyllanthus_niruri_Foto.html)

Conclusions

Concentration and incidence of aflatoxins and fumonisins in maize kernels in Southeastern and Central Highlands of Vietnam were higher than zearalenone. However fumonisins should be noticed more in Vietnam due to its high concentration and incidence in the Central Highlands areas.

Aflatoxins should still be carefully monitored because of its high and dangerous level in positive samples

References

CAST 1903: Mycotoxins. Risk in plant, animal, and human systems. Task Force Report, No. 139 January 2003. Council for Agricultural Science and Technology, Ames, Iowa.

Casteel S W, Turk J R, Cowart R P, Rottinghaus G E 1993: Chronic toxicity of fumonisin in weanling pigs. Journal of Veterinary Diagnostic Investigation, Vol. 5, p. 413-417 1993

Chi M S, Mirocha C J, Weaver G A and Kurtz H J 1980: Effect of Zearalenone on Female White Leghorn Chickens, 1980. Applied and Environmental Microbiology, Vol. 39, No. 5, p. 1026-1030, May 1980

Islam A, Selvan T , Mazumder U K, Gupta M, Ghosal S 1908: Antitumour effect of phyllanthin and hypophyllanthin from Phyllanthus marus against Ehrlich ascites carcinoma in mice. Pharmacology online, Vol. 2, p. 796-807, 2008

Osweiler G D 1996: Toxicology. Wiley-Blackwell, 1996, p.420 , fromhttp://books.google.com/books?id=l7Wpmj0AK88C&pg=PA420&dq=zearalenone&cd=9#v=onepage&q=zearalenone&f=false

Smith G W, Constable P D and Haschek W M 1996 b: Cardiovascular Responses to Short-Term Fumonisin Exposure in Swine. Fundamental and Applied Toxicology, Vol. 33, p. 140–148, 1996

Smith G W, Constable P D, Bacon C W, Meredith F and Haschek W M 1996 a: Cardiovascular Effects of Fumonisins in Swine. Fundamental and Applied Toxicology, Vol. 31, p. 169–172, 1996

Tran S T, Bailly J D, Tardieu D, Durand S, Benard G, Guerre P 1903: Sphinganine to sphingosine ratio and predictive biochemical markers of fumonisin B1 exposure in ducks. Chemico-Biological Interactions, Vol. 146, p. 61-72, 2003

Voss K A, Howard P C, Riley R T, Sharma R P, Bucci T J, VMD, Lorentzen R J 1901: Carcinogenicity and mechanism of action of fumonisin B1 : a mycotoxin produced by Fusarium moniliforme (=F. verticillioides). Cancer Detection and Prevention, Vol. 26, p. 1–9, 2002

Nong Lam University, Department of Animal Nutrition,
Ho Chi Minh city, Vietnam

Tran S T, Bailly J D, Tardieu D, Durand S, Benard G, Guerre P 1903: Sphinganine to sphingosine ratio and predictive biochemical markers of fumonisin B₁ exposure in ducks. Chemico-Biological Interactions, Vol. 146, p. 61-72, 2003

Voss K A, Howard P C, Riley R T, Sharma R P, Bucci T J, VMD, Lorentzen R J 1901: Carcinogenicity and mechanism of action of fumonisin B₁ : a mycotoxin produced by Fusarium moniliforme (=F. verticillioides). Cancer Detection and Prevention, Vol. 26, p. 1–9, 2002