A. Piva

Dietary Strategies to Counteract the Effects of Mycotoxins: A Review

We reviewed various dietary strategies to contain the toxic effects of mycotoxins using antioxidant compounds (selenium, vitamins, provitamins), food components (phenolic compounds, coumarin, chlorophyll and its derivatives, fructose, aspartame), medicinal herbs and plant extracts, and mineral and biological binding agents (hydrated sodium calcium aluminosilicate, bentonites, zeolites, activated carbons, bacteria, and yeast). Available data are primarily from in vitro studies and mainly focus on aflatoxin B1, whereas much less information is available about other mycotoxins. Compounds with antioxidant properties are potentially very efficacious because of their ability to act as superoxide anion scavengers. Interesting results have been obtained by food components contained in coffee, strawberries, tea, pepper, grapes, turmeric, Fava tonka, garlic, cabbage, and onions. Additionally, some medicinal herbs and plant extracts could potentially provide protection against aflatoxin B1 and fumonisin B1. Activated carbons, hydrated sodium calcium aluminosilicate, and bacteria seem to effectively act as binders. We conclude that dietary strategies are the most promising approach to the problem, considering their limited or nil interference in the food production process. Nevertheless, a great research effort is necessary to verify the in vivo detoxification ability of the purposed agents, their mode of action, possible long-term drawbacks of these detoxification-decontamination procedures, and their economical and technical feasibility.

DETOXIFICATION METHODS OF AFLATOXINS. A REVIEW.

Detoxification of aflatoxin contaminated foods and feeds is a current problem, as aflatoxins are highly carcinogenic and capable of passing unaltered through metabolic processes and accumulating in the tissues (seriously jeopardizing human and animal health). Although numerous detoxification methods have been tested, none seems able to fulfill the efficacy, safety, safeguarding of nutritional elements and costs requisites of a detoxification process. This paper critically reviews the main chemical detoxification methods and the latest approach to the problem using added sorbents capable of adsorbing aflatoxins.

Viability of a Five-Strain Mixture of Listeria monocytogenes in Vacuum-Sealed Packages of Frankfurters, Commercially Prepared with and without 2.0 or 3.0% Added Potassium Lactate, during Extended Storage at 4 and 10° C†‡

The viability of Listeria monocytogenes was monitored on frankfurters containing added potassium lactate that were obtained directly from a commercial manufacturer. Eight links (ca. 56 g each) were transferred aseptically from the original vacuum-sealed bulk packages into nylon-polyethylene bags. Each bag then received a 4-ml portion of a five-strain mixture of the pathogen. Frankfurters containing 2.0 or 3.0% potassium lactate were evaluated using 20 CFU per package, and frankfurters containing 3.0% potassium lactate were evaluated using 500 CFU per package. The packages were vacuum-sealed and stored at 4 or 10 degrees C for up to 90 or 60 days, respectively. During storage at 4 degrees C, pathogen numbers remained at about 1.6 log10 CFU per package over 90 days in packages containing frankfurters with 2.0% potassium lactate that were inoculated with about 20 CFU. In packages containing frankfurters with 3.0% potassium lactate that were inoculated with about 20 CFU and stored at 4 degrees C, pathogen numbers remained at about 1.4 log10 CFU per package over 90 days. In packages containing frankfurters with 3.0% potassium lactate that were inoculated with about 500 CFU and stored at 4 degrees C, pathogen numbers remained at about 2.4 log10 CFU per package over 90 days. However, in the absence of any added potassium lactate, pathogen numbers increased to 4.6 and 5.0 log10 CFU per package after 90 days of storage at 4 degrees C for starting levels of 20 and 500 CFU per package, respectively. During storage at 10 degrees C, pathogen numbers remained at about 1.4 log10 CFU per package over 60 days in packages containing frankfurters with 2.0% potassium lactate that were inoculated with about 20 CFU. In packages containing frankfurters with 3.0% potassium lactate that were inoculated with about 20 CFU and stored at 10 degrees C, pathogen numbers remained at about 1.1 log10 CFU per package over 60 days of storage. In the absence of any added potassium lactate, pathogen numbers increased to 6.5 log10 CFU per package after 28 days and then declined to 5.0 log10 CFU per package after 60 days of storage at 10 degrees C. In packages containing frankfurters with 3.0% potassium lactate that were inoculated with about 500 CFU per package, pathogen numbers remained at about 2.4 log10 CFU per package over 60 days of storage at 10 degrees C, whereas in the absence of any added potassium lactate, pathogen numbers increased to about 6.6 log10 CFU per package within 40 days and then declined to about 5.5 log10 CFU per package after 60 days of storage. The viability of L. monocytogenes in frankfurter packages stored at 4 and 10 degrees C was influenced by the pH and the presence or levels of lactate but not by the presence or levels of indigenous lactic acid bacteria or by the proximate composition of the product. These data establish that the addition of 2.0% (P < 0.0004) or 3.0% (P < 0.0001) potassium lactate as an ingredient in frankfurters can appreciably enhance safety by inhibiting or delaying the growth of L. monocytogenes during storage at refrigeration and abuse temperatures.

Reduction of carryover of aflatoxin from cow feed to milk by addition of activated carbons

According to a double-reversal experimental design on 12 late-lactation Friesian cows the effect of two activated carbons (ACs) (CAC1 and CAC2) and a hydrated sodium calcium aluminosilicate (HSCAS) on carryover of aflatoxin B1 (AFB1) from feed to aflatoxin M1 (AFM1) in milk was determined. Cows were fed a basal diet containing AFB1 naturally contaminated corn meal and copra, During week 1 cows were fed diets containing AFB1 alone (11.28 μg of AFB1/kg of feed); in week 2 the diets contained AFB1 plus 2.0% sorbent; and in week 3 the diets again contained AFB1 alone (13.43 μg of AFB1/kg of feed). ACs reduced the analytical content of AFB1 in the pelleted feed by from 40.6% to 73.6%, whereas reduction by HSCAS was 59.2%, The AFM1 concentrations in milk in weeks 1 and 3 were higher than that in week 2, Decreases in the AFM1 excreted in the milk by addition to feed of 2% of the sorbents ranged from 22% to 45%. CAC1 and HSCAS were significantly different from each other in reducing the AFM1concentration in milk (45.3% versus 32.5%); these reductions were significantly higher than that of CAC2 (22.0%). Carryover reduction by addition of CAC1 (50%) was significantly higher than that of HSCAS (36%). Addition of 2% CAC2 did not allow pelleting of feed because of the caking action of this carbon, The lower performance of CAC2 could be related to the unsuccessful pelleting. The addition of ACs did not influence feed intake, milk production, milk composition, or body weight. Our results suggest that ACs, high-affinity sorbents for AFB1 in vitro, are efficacious in reducing AFB1 carryover from cow feed to milk. Further in vivo investigations should establish lower amounts of ACs which can be efficacious.

Activated carbons: in vitro affinity for ochratoxin A and deoxynivalenol and relation of adsorption ability to physicochemical parameters.

In vitro affinity tests were conducted to test the effectiveness of 19 activated carbons (ACs), hydrates sodium calcium aluminosilicate (HSCAS) and sepiolite (S) in binding ochratoxin A (OA) and deoxynivalenol (DON) from solution. Relationships between adsorption ability and physicochemical parameters of ACs (surface area, iodine number, methylene blue index) were tested. When 5 ml of a 4-micrograms/ml aqueous solution of OA was treated with 2 mg of AC, the ACs adsorbed 0.80 to 99.86% of the OA. HSCAS and S were not effective in binding OA. In two saturation tests carried out with increased amounts of OA (5 ml of 10-and 50-micrograms/ml aqueous solutions of OA, respectively) three ACs also showed high adsorption ability (adsorbing 92.23 to 96.57% of the OA). When 5 ml of a 4-micrograms/ml aqueous solution of DON was treated with 10 mg of AC, ACs adsored 1.83 to 98.93% of the DON. HSCAS and S were not effective in binding DON. An overall relation of adsorption ability to the physicochemical parameters of ACs was observed. The methylene blue index was more reliable than iodine number and surface area in predicting ability of ACs to adsorb OA and DON. Based on the data observed on the xxxxx eh present study as well as on aflatoxin B1 and fumonisin B1 from previous studies, it is concluded that ACs have high in vitro affinity for chemically different mycotoxins, and can be considered as potential multi-mycotoxin-sequestering agents. However, the ability to bind the main mycotoxins singly or in combination should be confirmed by in vivo investigations. Moreover, information on the amounts of AC to be added to feeds, and on the possible long-term effect on absorption of essential nutrients are needed.

Sodium butyrate improves growth performance of weaned piglets during the first period after weaning

Abstract The purpose of the present work was to evaluate whether the addition of sodium butyrate to feed could facilitate weaning and growth response in piglets. For 56 days two groups of 20 piglets (9.2±1.4 kg LW) were fed an acidified basal diet (containing formic and lactic acid at 0.5 and 1.5 g/kg of feed, respectively) without (control group) or with sodium butyrate (SB) at 0.8 g/kg. Average daily gain (ADG), daily feed intake (DFI), feed efficiency (FE) and live weight (LW) were recorded. In the first two weeks, butyrate supplementation increased ADG (+20%; P<0.05) and DFI (+16%; <0.05). During the subsequent period (15 to 35 days) animals fed SB had a higher DFI but lower feed efficiency (+10% and -14%, respectively; P<0.05) than animals fed the control diet. No other benefits were observed thereafter. The data presented showed that the use of sodium butyrate facilitated only the initial phase of adaptation to a solid diet in piglets.

An organic acid blend can modulate swine intestinal fermentation and reduce microbial proteolysis

The increased use of slow-release organic acids in swine nutrition has prompted more research to assess their possible role in modulating the intestinal microflora as an alternative to antibiotics. Three diets for growing pigs containing 0 (L-NDF), 100 (M-NDF), and 200 g kg-1 (H-NDF) dried sugar beet pulp (SBP) were pre-digested to simulate ileal digestion, and used as substrate in an in vitro cecal fermentation study. The inoculum was collected from pigs immediately after slaughter. Diets tested were L-NDF, M-NDF, and H-NDF with or without the addition of an organic acid blend providing phosphoric, citric, fumaric, and malic acid at 1.53, 0.78, 2.59, and 1.12 mmol L-1, respectively. Cecal microbial growth was monitored using the cumulative gas production technique. Fermentation fluid was analyzed for ammonia and volatile fatty acids concentrations. The maximum rate of gas production was higher when H-NDF rather than L-NDF or M-NDF (+ 18%; P < 0.05) was fed; such a high rate of growth (+ 14%; P < 0.05) wa...

Determination of nitrogen intestinal digestibility in ruminants

The aim of this study was to compare two procedures used to estimate post-abomasal availability of feedstuff proteins in ruminants: (1) nitrogen disappearance from intestinal nylon bags; (2) true intestinal digestibility (dr). Dietary amino acid supplies and digestibilities were also evaluated. Three Italian Holstein rumen- and duodenum-fistulated cows were used. Animals were fed at an energy level equal to 1.7 times the maintenance requirement. Of the 29 proteic feedstuffs tested, 19 had intestinal digestibilities of over 90%: 17 of these were of vegetable origin and two were of animal origin. Nylon bag intestinal protein disappearances were over 90% for only 11 feedstuffs. Eighteen feedstuffs did not show any differences between the two procedures, while intestinal digestibility appeared superior to protein disappearance in ten raw materials (the opposite result was obtained in only one feedstuff). Amino acid intestinal digestibilities corresponded to source protein composition.

Protective effect of cyanidin 3- O -β- d -glucoside on ochratoxin A-mediated damage in the rat

The aim of the present study was to verify whether the oral administration of cyanidin 3-O-beta-D-glucoside (C3G) might counteract damage induced by chronic exposure (28 d) to ochratoxin A (OTA) in rats and if its effect may be mediated by haeme oxygenase-1 (HO-1). Forty male Sprague-Dawley rats, individually caged, were divided into four groups of ten animals. A control group received a commercial diet, group C3G received the control diet supplemented with C3G (1 g/kg feed), group OTA received the control diet supplemented with 200 parts per billion of OTA, and group OTA+C3G received the OTA group diet supplemented with C3G (1 g/kg feed). After 4 weeks of treatment animals were killed and the liver, kidneys and brain of each rat were collected and homogenised to evaluate non-proteic thiol groups (RSH), lipid hydroperoxide (LOOH) levels, HO-1 expression and DNA fragmentation. Rats of the OTA group showed a significant (P < 0.001) decrease in RSH content of kidney and liver and a significant (P < 0.001) increase of LOOH in all the examined tissues compared with the control group. In the OTA+C3G group both RSH content and LOOH levels were similar to those observed in the control group, demonstrating that C3G was able to counteract the effects of OTA. A significant (P < 0.001) induction of HO-1 was evident in kidney and liver of both OTA and C3G groups. DNA damage occurred in all the examined tissues of the OTA group, whereas C3G was able to prevent it. The present study confirmed that the effects of OTA are mediated by oxidative stress and demonstrated that C3G efficiently counteracted deleterious effects of OTA because of its antioxidant and HO-1-inducing properties.

Effect of microcapsulation on absorption processes in the pig

Abstract The effect of microcapsulation with long-chain fatty acids (LCFA) on the absorption and bioavailability of nutrients and drugs was studied in pigs using microcapsulated tryptophan (TRY) and sulfamethazine (SMT). Portal concentrations of tryptophan were monitored in gilts fed a basal diet supplemented with 1.75 and 10.75 g pig −1 day −1 free-crystalline or microcapsulated TRY. Sulfamethazine plasma kinetics were studied in gilts orally administered with free-base or microcapsulated drugs (1 g pig −1 ) at feeding time. Blood samples were collected until 8 h and 120 h after feeding in pigs treated with TRY and SMT, respectively. Absorbed fractions of both microcapsulated TRY and SMT were lower than in the free forms by 26 and 32%, respectively, 8 h after treatment. Nevertheless, total drug bioavailability measured by the area under the plasma concentration-time curve extrapolated to infinity (AUC 0 − ∞ ) was not modified by microcapsulation (970 ± 202 vs. 959 ± 355 μg ml −1 h). These data suggest that microcapsulation delays absorption without affecting the bioavailability of protected compounds.