Human health effects of conjugated linoleic acid from milk and supplements

Short communication: A nanoemulsified form of oil blends positively affects the fatty acid proportion in ruminal batch cultures

Two consecutive rumen batch cultures were used to study the effect of nanoemulsified oils as a new type of supplement, on the in vitro fatty acid proportion and vaccenic acid formation. Three levels (3, 5, and 7%) of 2 different oil blends [soybean:fish oil (SF) or rapeseed-fish oil (RF)] were used. Both oil blends were used either in the raw form (SF or RF, respectively) or in the nanoemulsified form (NSF or NRF, respectively). The diets were the control (0%), which consisted of a dry total mixed ration without any supplements, the control plus 3, 5, or 7% of the SF or RF oil blend in appropriate form (raw or nanoemulsified). For each treatment, 6 incubation vessels were used. Each batch culture was incubated for 24h and conducted twice in 2 consecutive days. All supplements were calculated as a percentage of the substrate dry matter (400mg). Nanoemulsified supplements were recalculated to make sure the oil amount was equal to the raw oil supplementation levels. The results from both experiments indicated that the proportions of vaccenic acid and cis-9,trans-11 C18:2 increased when a raw oil blend was supplemented; on the other hand, no influence of nanoemulsified form of oil blend was observed on the proportion cis-9,trans-11 C18:2. Generally, supplementation with the nanoemulsified oil blends had less effect on biohydrogenation intermediates than the raw form of oil blends. However, the nanoemulsified form had a greater effect on the increase of n-3 and n-6 fatty acids. Nanoemulsified oil blends had a positive effect on decreasing the transformation rate of polyunsaturated fatty acids to saturated fatty acids in the biohydrogenation environment. Supplements of nanoemulsified oil blends tended to be more effective than supplements of raw oils in preserving a greater proportion of polyunsaturated fatty acids in the fermentation culture.

Functional foods as potential therapeutic options for metabolic syndrome

Obesity as part of metabolic syndrome is a major lifestyle disorder throughout the world. Current drug treatments for obesity produce small and usually unsustainable decreases in body weight with the risk of major adverse effects. Surgery has been the only treatment producing successful long-term weight loss. As a different but complementary approach, lifestyle modification including the use of functional foods could produce a reliable decrease in obesity with decreased comorbidities. Functional foods may include fruits such as berries, vegetables, fibre-enriched grains and beverages such as tea and coffee. Although health improvements continue to be reported for these functional foods in rodent studies, further evidence showing the translation of these results into humans is required. Thus, the concept that these fruits and vegetables will act as functional foods in humans to reduce obesity and thereby improve health remains intuitive and possible rather than proven.

Therapeutic and Prophylactic Potential of Morama (Tylosema esculentum): A Review

Tylosema esculentum (morama) is a highly valued traditional food and source of medicine for the San and other indigenous populations that inhabit the arid to semi-arid parts of Southern Africa. Morama beans are a rich source of phenolic acids, flavonoids, certain fatty acids, non-essential amino acids, certain phytosterols, tannins and minerals. The plant's tuber contains griffonilide, behenic acid and starch. Concoctions of extracts from morama bean, tuber and other local plants are frequently used to treat diarrhoea and digestive disorders by the San and other indigenous populations. Information on composition and bioactivity of phytochemical components of T. esculentum suggests that the polyphenol-rich extracts of the bean testae and cotyledons have great potential as sources of chemicals that inhibit infectious microorganisms (viral, bacterial and fungal, including drug-resistant strains), offer protection against certain non-communicable diseases and promote wound healing and gut health. The potential antinutritional properties of a few morama components are also highlighted. More research is necessary to reveal the full prophylactic and therapeutic potential of the plant against diseases of the current century. Research on domestication and conservation of the plant offers new hope for sustainable utilisation of the plant.

Quality traits and modeling of coagulation, curd firming, and syneresis of sheep milk of Alpine breeds fed diets supplemented with rumen-protected conjugated fatty acid

The aim of this study was to test the modeling of curd-firming (CF) measures and to compare the sheep milk of 3 Alpine breeds supplemented with or without rumen-protected conjugated linoleic acid (rpCLA). Twenty-four ewes of the Brogna, Foza, and Lamon breeds were allotted to 6 pens (2 pens/breed) and fed a diet composed of corn grain, corn silage, dried sugar beet pulp, soybean meal, wheat bran, wheat straw, and a vitamin-mineral mixture. The rpCLA supplement (12 g/d per ewe plus 4 g/d for each lamb older than 30 d) was mixed into the diet of 1 pen per sheep breed (3 pens/treatment) to provide an average of 0.945 and 0.915 g/d per ewe of the cis-9,trans-11 C18:2 and trans-10,cis-12 C18:2 conjugated linoleic acid isomers, respectively. The trial started at 38 ± 23 d after parturition, and individual morning milk samples were collected on d 16, 23, 37, 44, and 59 of the trial. Milk samples were analyzed for composition, and duplicate samples were assessed for milk coagulation properties (MCP). A total of 180 CF measures for each sample (1 every 15s) were recorded. Model parameters were the rennet coagulation time, the asymptotic potential CF, the CF instant rate constant, the syneresis instant rate constant, the maximum CF achieved within 45 min (CFmax), and the time at achievement of CFmax. The data were analyzed using a hierarchical model that considered the fixed effects of breed, diet, lamb birth, and initial days in milk, which were tested on individual ewe (random) variance; the fixed effect of sampling day, which was tested on the within-ewe sample (random) variance; and the fixed effect of instrument or cuvette position (only for MCP), which was tested on the residual (replicates within samples) variance. The local Alpine sheep breeds displayed similar milk compositions, traditional MCP, and CF modeling parameters. Supplementation with rpCLA triggered changes in milk composition and worsened MCP (e.g., delayed rennet coagulation time, slower CF instant rate constant, and a doubling of syneresis instant rate constant), but did not influence potential CF. Overall, our results indicate that rpCLA supplementation reduced the actual maximum CF (CFmax) but did not modify the interval between rennet addition and CFmax or time to CFmax.

Bioavailability and allergoprotective capacity of milk-associated conjugated linoleic acid in a murine model of allergic airway inflammation

BACKGROUND

Cross-sectional epidemiological studies have demonstrated that farm milk from traditional farm settings possesses allergoprotective properties. Up to now, it has not been clarified which milk ingredient is responsible for protection against allergic diseases. As farm milk is rich in conjugated linoleic acids (CLA), it is hypothesized that this n-3 polyunsaturated fatty acid family contributes to the allergoprotective capacity of farm milk. We aim to prove this hypothesis in a murine model of allergic airway inflammation.

METHODS

To prove the bioavailability and allergoprotective capacity of milk-associated CLA in a standardized protocol, milk batches that differed significantly in terms of their CLA content were spray dried and incorporated into a basic diet by substituting the regular sunflower fat fraction. Initially, the milk CLA uptake from the diet was monitored via measurement of the CLA content in plasma and erythrocyte membranes obtained from supplemented mice. To determine whether a milk CLA-enriched diet possesses allergoprotective properties, female Balb/c mice were fed the milk CLA-enriched diet ahead of sensitization and a challenge with ovalbumin (OVA) and the parameters of airway inflammation and eisosanoid pattern were measured.

RESULTS

In animals, supplementation with a diet rich in milk CLA resulted in elevated CLA levels in plasma and erythrocyte membranes, indicating bioavailability of milk fatty acids. Though membrane-associated phospholipid patterns were affected by supplementation with milk CLA, this application neither reduced the hallmarks of allergic airway inflammation in sensitized and OVA-challenged mice nor modified the eiconsanoid pattern in the bronchoalveolar lavage fluid of these animals.

CONCLUSION

Milk-associated CLA was not capable of preventing murine allergic airway inflammation in an animal model of OVA-induced allergic airway inflammation.

Identification of conjugated linoleic acid (CLA) isomers by silver ion-liquid chromatography/in-line ozonolysis/mass spectrometry (Ag+-LC/O3-MS)

A novel method for the identification of conjugated linoleic acid (CLA) isomers has been developed in which silver ion liquid chromatography is coupled to in-line ozonolysis/mass spectrometry (Ag(+)-LC/O3-MS). The mobile phase containing CLA isomers eluting from the Ag(+)-LC column flows through a length of gas-permeable tubing within an ozone rich environment. Ozone penetrating the tubing wall reacts with the conjugated double bonds forming ozonolysis product aldehydes. These, and their corresponding methanol loss fragment ions formed within the atmospheric pressure photoionization (APPI) source, were detected by in-line MS and used for the direct assignment of double bond positions. Assignment of positional isomers is based entirely on the two pairs of diagnostic ions seen in the in-line O3-MS mass spectra. In this way, de novo identification of CLA positional isomers, i.e. without requiring comparison to CLA standards, was achieved. The Ag(+)-LC/O3-MS method was applied to the analysis of CLA isomers in a commercial CLA supplement, milk fat, and the lipid extract from a Lactobacillus plantarum TMW1460 culture. The results demonstrate how Ag(+)-LC/O3-MS can be used for the direct and fast determination of CLA isomers at low concentrations and in complex lipid mixtures.

Effect of vitamin E on milk composition of grazing dairy cows supplemented with microencapsulated conjugated linoleic acid

The objective of this study was to evaluate the effect of vitamin E on the fat content and fatty acid profile of grazing dairy cows supplemented with microencapsulated conjugated linoleic acid. Eight New Zealand Holstein cows in a rotational grazing system were used, in a crossover design, randomly assigned to four treatments: control (base diet with microencapsulated conjugated linoleic acid) and three levels of vitamin E (control with 4,000; 8,000; and 12,000 IU/cow per day). All the cows received a supplement apportioning 5 g of cis-9, trans-11, and 5 g of trans-10, cis-12 of conjugated linoleic acid. Moreover, they each received 4-kg dry matter (DM) concentrate and 3.2-kg DM corn silage every day. There were no differences in dry matter intake, milk production, milk composition (fat, protein, and lactose), or fatty acid profile as an effect of vitamin E, and fat content remained under 3 % in all treatments. Therefore, under the conditions that this experiment was carried out, high concentrations of vitamin E in the diet of grazing dairy cows do not inhibit milk fat depression associated with conjugated linoleic acid. It also has no effect on the fatty acid profile of the milk.

Antifungal lipids produced by lactobacilli and their structural identification by normal phase LC/atmospheric pressure photoionization−MS/MS

Lactobacillus hammesii converts linoleic acid into an antifungal hydroxy fatty acid. High speed counter-current chromatography (HSCCC) using a hexane/ethyl acetate/methanol/water solvent system [3.5:1.5:3:2 (v/v/v/v)] allowed isolation of the antifungal hydroxy fatty acid. A method was developed for characterization of antifungal hydroxy fatty acids using normal phase liquid chromatography combined with atmospheric pressure photoionization-tandem mass spectrometry (LC/APPI-MS/MS). The position of unsaturations and hydroxyl groups was determined directly from crude lipid extracts and their hydroxylated derivatives. The antifungal compounds were identified as a racemic mixture of 10-hydroxy-cis-12-octadecenoic and 10-hydroxy-trans-12-octadecenoic acid. Additionally, HSCCC and LC/APPI-MS/MS methods were used to elucidate the pathway of conversion of linoleic acid by Lactobacillus sanfranciscensis , Lactobacillus plantarum , and L. hammesii to hydroxy fatty acids and conjugated linoleic acid. This study links previously reported 10-hydroxy-12-octadecenoic acid producing Lactobacillus strains to antifungal activities.

Influence of alternative lifestyles on self-reported body weight and health characteristics in women

BACKGROUND

Alternative lifestyles are often associated with distinct practices with respect to nutrition, physical activity, smoking, alcohol use and usage of complementary medicine. Evidence concerning effects of these lifestyle-related practices on health status is still fragmentary.

OBJECTIVE

To describe maternal health characteristics related to alternative lifestyles, with emphasis on body-weight status, during pregnancy and maternity periods.

METHODS

We compared self-reported health-related features of mothers with alternative lifestyles and conventional lifestyles during pregnancy and maternity period in the KOALA Birth Cohort Study. This cohort comprises two recruitment groups of mother-infant pairs, one with a conventional (no selection based on lifestyle, n = 2333), the other with an alternative lifestyle (selected via organic food shops, anthroposophic clinicians and midwives, anthroposophic under-five clinics, Rudolf Steiner schools and relevant magazines, n = 485). Mothers in the alternative group more frequently chose organic foods, adhered to specific living rules, practised vegetarianism and identified themselves with anthroposophy.

RESULTS

Mothers in the alternative group showed lower BMI and lower prevalence of overweight and obesity than the conventional group, before pregnancy as well as 4-5 years after delivery. This difference was partly retained after adjusting for potential confounders. Furthermore, women in the alternative group had a lower prevalence of pregnancy-related hypertension, more often started breastfeeding and gave exclusive and prolonged breastfeeding for a longer period. Finally, they smoked less often, but more often drunk alcohol during pregnancy.

CONCLUSION

The results suggest that an alternative lifestyle is associated with favourable body weight and with several differences in other health features.

Current issues surrounding the definition of trans-fatty acids: implications for health, industry and food labels

The definition of trans-fatty acids (TFA) was established by the Codex Alimentarius to guide nutritional and legislative regulations to reduce TFA consumption. Currently, conjugated linoleic acid (CLA) is excluded from the TFA definition based on evidence (primarily preclinical studies) implying health benefits on weight management and cancer prevention. While the efficacy of CLA supplements remains inconsistent in randomised clinical trials, evidence has emerged to associate supplemental CLA with negative health outcomes, including increased subclinical inflammation and oxidative stress (particularly at high doses). This has resulted in concerns regarding the correctness of excluding CLA from the TFA definition. Here we review recent clinical and preclinical literature on health implications of CLA and ruminant TFA, and highlight several issues surrounding the current Codex definition of TFA and how it may influence interpretation for public health. We find that CLA derived from ruminant foods differ from commercial CLA supplements in their isomer composition/distribution, consumption level and bioactivity. We conclude that health concerns associated with the use of supplemental CLA do not repudiate the exclusion of all forms of CLA from the Codex TFA definition, particularly when using the definition for food-related purposes. Given the emerging differential bioactivity of TFA from industrial v. ruminant sources, we advocate that regional nutrition guidelines/policies should focus on eliminating industrial forms of trans-fat from processed foods as opposed to all TFA per se.

Short communication: effect of oilseed supplementation of an herbage diet on ruminal fermentation in continuous culture

A 4-unit continuous culture fermentor system was used to evaluate the effects of oilseed supplementation of an herbage-based diet on nutrient digestibility, fermentation profile, and bacterial nitrogen (N) synthesis. Treatments were randomly assigned to fermentors in a 4×4 Latin square design with 7d for diet adaptation and 3d for data and sample collection. Dietary treatments were an herbage-only diet (HERB), or the following ground oilseeds supplemented to an herbage-based diet at 10% of total dry matter (DM) fed: flaxseed (FLAX), canola (CAN), or sunflower (SUN). Apparent DM, organic matter, and neutral detergent fiber digestibility were not affected by diet, averaging 62, 68, and 78%, respectively. True DM and organic matter digestibility were not affected by diet, averaging 78 and 82%, respectively. Fermentor pH and total volatile fatty acids were not affected by diet. Branched-chain volatile fatty acids tended to be lower for HERB compared with the 3 oilseed diets. Ammonia N concentrations were lowest for the HERB diet. Crude protein digestibility was not affected by diet. Flow of NH3-N was lowest for the HERB diet reflecting the lowest culture concentration of NH3-N. Bacterial N flows were lowest for HERB and SUN diets, intermediate for FLAX, and greatest for CAN. Flows of total N, non-NH3-N, and dietary N were not affected by diet. Likewise, efficiency of bacterial N synthesis was not affected by diet. Supplementation with FLAX, CAN, or SUN at 10% of total DM fed did not affect nutrient digestibility or ruminal fermentation compared with an all-herbage diet. The oilseeds tested herein may be considered as alternative energy supplements for grazing dairy cows, particularly during times of low availability of corn. However, in vivo studies are needed to further evaluate the effects of oilseeds supplementation of an herbage-based diet on milk production and composition (specifically human-beneficial fatty acids).

Caenorhabditis elegans as a model to study the effectiveness and metabolic targets of dietary supplements used for obesity treatment: the specific case of a conjugated linoleic acid mixture (Tonalin)

The antiobesity effect of conjugated linoleic acid (CLA) has previously been described in different animal models. The aim of the present study was to investigate the effect of a commercial mixture (Tonalin) on Caenorhabditis elegans to assess their potential use for functional ingredient screenings. Body-fat reduction with Tonalin was demonstrated in wild-type strain N2. The 1 μg/mL dose was the most effective, either alone or added to a food matrix, and also significantly decreased triglyceride content in nematodes fed on the CLA mixture. Furthermore, the antiobesity effect was related to the CLA isomer trans-10, cis-12. Finally, the transcriptional study showed C. elegans fed with Tonalin (1 μg/mL) underwent an upregulation of energy metabolism, reproduction, protein metabolism and oxidative stress processes. In conclusion, the results presented here clearly correlate well with other animal studies, demonstrating the value of C. elegans as a useful model to evaluate antiobesity compounds/ingredients.