Beta-palmitate - a natural component of human milk in supplemental milk formulas

Feeding infant formula with low sn-2 palmitate causes changes in newborn's intestinal environments through an increase in fecal soaped palmitic acid

BACKGROUND/OBJECTIVES

Soaped palmitic acid (PA) has been reported to be excreted in stool after feeding infant formulas containing low sn-2 palmitate levels, which corresponds to high sn-1 or -3 palmitate levels. While an in vitro study showed that soaped PA inhibits the Bifidobacteria growth, few clinical studies have evaluated effects of soaped PA on intestinal environments of infants. In this study, we aimed to evaluate associations between increased fecal soaped PA levels and inhibition of growth of the intestinal microbiome using clinical data, and to evaluate changes in the intestinal environment with formula-feeding.

METHODS

This study was conducted as a secondary analysis to our observational study of Japanese 1-month-old infants (n = 172). Infant formulas were classified into high sn-2 formula (≥ 50%) and low sn-2 formula (< 50%) according to the sn-2 binding ratio of PA. Multiple regression analyses and path analysis were performed as statistical analyses.

RESULTS

In the multiple regression analysis, the occupancy of Bifidobacteria was negatively correlated with the fecal soaped PA levels (β = -0.15, 95% confidence interval = -0.28- - 0.02). A path analysis suggested that low sn-2 formula feeding led to increased fecal soaped PA levels, decreased Bifidobacteria occupancy, and finally increased fecal pH.

CONCLUSIONS

Our clinical data showed significant associations between higher fecal soaped PA levels and lower Bifidobacteria occupancy in the newborn gut, which agreed well with the report of the in vitro study. Our study also suggests that feeding infant formula with low sn-2 palmitate causes changes in the intestinal environment through an increase in fecal soaped palmitic acids.

Growth and gastrointestinal tolerance of healthy formula-fed infants: a multicentre, prospective observational study

BACKGROUND

Infant formula with human milk oligosaccharides (HMOs) and increased β-palmitate mimics breast milk nutritional composition and clinical benefits. We aimed to assess formula-fed infant growth, gastrointestinal tolerance, infections, and parental satisfaction with a partly fermented infant formula with an improved lipid profile (enriched with β-palmitate and docosahexaenoic/arachidonic acid) and short and long-chain oligosaccharides (scGOS/lcFOS [9:1]) and HMOs.

METHODS

A prospective descriptive observational study in healthy infants with formula feeding or breastfeeding (reference population) was conducted in six Spanish primary care centres following routine clinical practice. In the first, second and fourth month of life visits sociodemographic, clinical, and anthropometric variables (weight, length, head circumference), stool consistency (Brussels Infant and Toddler Stool Scale [BITSS]), gastrointestinal symptoms, infections incidence and associated healthcare resource utilisation, and caregivers' satisfaction with formula were collected. A descriptive statistical analysis was performed (STATA-v.14). Growth was estimated as the mean (standard deviation) increase in the anthropometric variables and z-scores.

RESULTS

A total of 61 formula-fed and 65 breastfed infants were included in the study (50.8% male). The average increase in weight, length and head circumference in the formula feeding and in the breastfeeding groups from the first to the fourth month of life was 2,566 (496) g, 9.7 (1.7) cm and 4.4 (1.0) cm, and 2,571 (702) g, 9.8 (1.8) cm and 4.4 (1.1) cm, respectively. The weight z-score was -0.1 (0.7) for formula-fed and 0.1 (1.1) for breastfed infants. In all visits, more than 88% of infants had loose/watery stools and most infants suffered gastrointestinal symptoms with low/medium frequency. In the fourth month of life visit, 16 (26.2%) formula-fed and 16 (24.6%) breastfed infants had infections, mainly respiratory, with 16% of formula-fed and 12% of breastfed infants requiring treatment. Most formula-feeding caregivers had a good/very good opinion of formula (85.2%). 75.4% infants drank the whole feeding bottle.

CONCLUSIONS

The growth, gastrointestinal tolerance, and incidence of infections of healthy formula-fed infants during the first four months of life were appropriate and in line with WHO standards. Formula feeding caregivers were satisfied with this partly fermented infant formula with an improved lipid profile and oligosaccharides.

A novel human milk fortifier supports adequate growth in very low birth weight infants: a non-inferiority randomised controlled trial

OBJECTIVE

To compare growth, tolerance and safety parameters in very preterm infants receiving human milk (HM) fortified with a multicomponent cow's milk-based HM fortifier (HMF; control) versus a novel HMF-containing lipids (including docosahexaenoic acid and arachidonic acid), higher protein and lower carbohydrate levels (test). Our hypothesis was that weight growth velocity in the test group would be non-inferior to that in the control group.

DESIGN

Double-blind, randomised controlled trial.

SETTING

Nine European neonatal intensive care units.

PATIENTS

HM-fed infants born at <32-week gestational age.

INTERVENTIONS

Fortification of HM with Test or Control HMF for a minimum of 21 days.

PRIMARY OUTCOME

Weight growth velocity between baseline and intervention day 21.

RESULTS

From March 2018 to July 2020, 102 and 103 infants were enrolled in the test and control groups, respectively. Weight growth velocity during the first 21 days in the test group (mean 18.4 g/kg/day) was non-inferior to that of controls (mean 18.5 g/kg/day), with a difference in estimated means of -0.175 g/kg/day (90% CI -1.34 to +0.99 g/kg/day; per-protocol population). No significant differences between groups were observed for gain in length, head circumference or anthropometric Z-scores. Rates of digestive intolerance, stool frequency and consistency were comparable. No significant differences were reported in common neonatal morbidities including necrotising enterocolitis (test: 2.9%, control: 6.9%, mean difference -4.0% (95% CI -11.1% to 2.2%); all subjects treated population).

CONCLUSIONS

Use of the novel HMF containing lipids, higher protein and lower carbohydrate levels supports adequate postnatal growth and appears safe and well tolerated in very preterm infants.

TRIAL REGISTRATION NUMBER

NCT03315221.

Infant formulas for the treatment of functional gastrointestinal disorders: A position paper of the ESPGHAN Nutrition Committee

Functional gastrointestinal disorders (FGID), such as infant regurgitation, infant colic, and functional constipation, are common and typically physiological phenomena during the early months of an infant's life and account for frequent consultations with pediatricians. Various infant formulas are marketed for their management and are frequently given by parents to infants before a medical consultation. However, the evidence supporting their effectiveness is limited and some have altered nutritional compositions when compared to standard formulas. Thus, these products should only be used under medical supervision and upon medical advice. Marketing and over-the-counter sales do not ensure proper medical guidance and supervision. The aim of this position paper is to review the current evidence regarding the safety and efficacy of formulas specifically formulated for addressing regurgitation, colic, and constipation, recognized as FGID. The objective is to provide guidance for clinical management based on the highest quality of available evidence. A wide search using Pubmed, MEDLINE, EMBASE and Cochrane Database of Systematic Reviews was performed including the MESH terms infant formula, colic, constipation, regurgitation, reflux, palmitate, lactase, lactose, magnesium, hydrolyzed protein, prebiotics or probiotics. 752 papers were identified and screened. Finally, 72 papers were included in the paper. In the absence of evidence, recommendations reflect the authors' combined expert opinion. Final consensus was obtained by multiple e-mail exchange and meetings of the Nutrition Committee. (1) For breastfed infants experiencing FGID such as regurgitation, colic, or constipation, transitioning from breastfeeding to commercial formulas is not recommended. (2) In general, whether an infant is breastfed or formula-fed, it's crucial to reassure parents that FGIDs are normal and typically do not necessitate treatment or change to a special formula. (3) Thickened formulas, often termed anti-reflux formulas, may be considered in specific cases of regurgitation. (4) The usage of specialized formulas for infants with colic is not advised due to a lack of clinical evidence. (5) In the case of constipation in infants, the use of formulas enriched with high β-palmitate and increased magnesium content may be considered to soften the stool. Generally, there is limited evidence supporting the use of specialized formulas for FGID. Breastfeeding should never be discontinued in favor of formula feeding.

Human milk-specific fat components enhance the secretion of ghrelin by MGN3-1 cells

Triacylglycerols (TAGs) are a major fat component in human milk. Since gastric lipase produces 1,2-diacylglycerol from TAGs, we focused on the bioactivity of human milk-derived diacylglycerols in stomach cells. Ghrelin is produced in the stomach and acts as an important regulator of growth hormone secretion and energy homeostasis. In this study, we showed that 1-oleoyl-2-palmitoylglycerol (OP) increased ghrelin secretion, whereas 1,3-dioleoyl-2-palmitoylglycerol (OPO), a major component of human milk TAGs, did not increase ghrelin secretion in the ghrelin-secreting cell line, MGN3-1. Therefore, diacylglycerol OP may directly contribute to the regulation of ghrelin secretion. We also found that 2-palmitoylglycerol and 1- and 2-oleoylglycerol increased ghrelin secretion. Finally, we demonstrated that intracellular cAMP levels and preproghrelin and ghrelin O-acyl transferase expression levels were enhanced by OP treatment in MGN3-1 cells. This may represent an example of a novel mother-infant interaction mediated by fat components derived from human breast milk.

Infant Formula with 50% or More of Palmitic Acid Bound to the sn-2 Position of Triacylglycerols Eliminate the Association between Formula-Feeding and the Increase of Fecal Palmitic Acid Levels in Newborns: An Exploratory Study

The binding ratio of palmitic acid (PA) at the sn-2 position of triacylglycerols in infant formulas is lower than that in breast milk, resulting in higher levels of fecal PA. Even if the ratio is increased to 40-50%, fecal PA levels in formula-fed infants remain higher than those in breast-fed infants. In Japan, infant formulas with 50% or more of PA bound to sn-2 (high sn-2 PA milk) are commercially available; however, their effects on PA excretion have not been investigated. Therefore, this observational study aimed to preliminarily evaluate whether the feeding volume of high sn-2 PA milk is significantly associated with fecal total/soaped PA levels in newborns. Infant formulas were classified as high (≥50% of PA bound to sn-2) or low sn-2 (<50%) PA milk. Associations between feeding volume of high or low sn-2 PA milk and fecal PA levels were evaluated using multiple regression analysis models. The results showed that the feeding volume of low sn-2 PA milk was positively associated with fecal total/soaped PA levels, while there was no significant association between those of high sn-2 PA milk and fecal total/soaped PA levels. Our preliminary study suggests that high sn-2 PA milk may reduce increased fecal PA levels in formula-fed newborns.

Detection and analysis of triacylglycerol regioisomers via electron activated dissociation (EAD) tandem mass spectrometry

Triacylglycerols (TGs) are important components of human diet. The positional distribution of fatty acids (FAs) on the glycerol backbone affects the chemistry and physical properties of fats. Especially for infants, the structure of TGs plays an important role in the growth and development. However, limited by detecting technology, accurately identifying regioisomers of ABA/AAB and BAC/ABC/ACB type TGs is a significant challenge for human milk utilization and the development of infant formula. For this, we exploit a novel method for identifying the regioisomers of ABA/AAB and BAC/ABC/ACB type TGs within complex lipid mixtures, via used electron activated dissociation (EAD) tandem mass spectrometry. The distribution information of acyl chains at the sn-2 and sn-1/3 positions of glycerol backbone and double bonds in unsaturated FAs can be easily obtained by fragmenting TG ions with energetic electrons (15 eV). Then, the standard curve was established by correlating the peak area intensity of sn-2 characteristic product ion with the content of TG regioisomers standard. These analytical methods successfully enabled the identification and quantification of TG regioisomers in human milk, cow milk, infant formula, palm oil, and sunflower oil. Additionally, the distribution of the double-bond positions of unsaturated FAs in these samples was also identified. Compared to traditional methods, this approach eliminates the need for complex processing and analysis procedures, enabling rapid structural characterization of ABA/AAB and BAC/ABC/ACB type TGs within 17 min. Hence, we provide a rapid and convenient methodology for detecting and analyzing ABA/AAB and BAC/ABC/ACB type TG regioisomers, thereby offering valuable assistance in the development of specialized formulations and facilitating effective process control for ensuring the quality of edible oils and fats.

Bioactive Analysis of Antibacterial Efficacy and Antioxidant Potential of Aloe barbadensis Miller Leaf Extracts and Exploration of Secondary Metabolites Using GC-MS Profiling

Aloe barbadensis Miller (ABM) is a traditional medicinal plant all over the world. Numerous studies were conducted to exhibit its medicinal properties and most of them were concentrated on its metabolites against human pathogens. The current research work evaluates the attributes of different polar-based extracts (ethanol, methanol, ethyl acetate, acetone, hexane, and petroleum ether) of dried Aloe barbadensis leaf (ABL) to investigate its phytochemical constituents, antioxidant potential (DPPH, ABTS), phenolic, tannin, flavonoid contents, identification of bioactive compounds, and functional groups by gas chromatography-mass spectrometry (GC-MS) and fourier transform infrared spectroscopy (FT-IR) respectively, and comparing antibacterial efficacy against human pathogens, aquatic bacterial pathogens, and zoonotic bacteria associated with fish and human. The present results showed that the methanolic extract of ABL showed higher antioxidant activity (DPPH-59.73 ± 2.01%; ABTS-74.1 ± 1.29%), total phenolic (10.660 ± 1.242 mg GAE/g), tannin (7.158 ± 0.668 mg TAE/g), and flavonoid content (49.545 ± 1.928 µg QE/g) than that of other solvent extracts. Non-polar solvents hexane and petroleum ether exhibited lesser activity among the extracts. In the case of antibacterial activity, higher inhibition zone was recorded in methanol extract of ABL (25.00 ± 0.70 mm) against Aeromonas salmonicida. Variations in antibacterial activity were observed depending on solvents and extracts. In the current study, polar solvents revealed higher antibacterial activity when compared to the non-polar and the mid-polar solvents. Diverse crucial bioactive compounds were detected in GC-MS analysis. The vital compounds were hexadecanoic acid (30.69%) and 2-pentanone, 4-hydroxy-4-methyl (23.77%) which are responsible for higher antioxidant and antibacterial activity. Similar functional groups were identified in all the solvent extracts of ABL with slight variations in the FT-IR analysis. Polar-based solvent extraction influenced the elution of phytocompounds more than that of the other solvents used in this study. The obtained results suggested that the ABM could be an excellent source for antioxidant and antibacterial activities and can also serve as a potential source of effective bioactive compounds to combat human as well as aquatic pathogens.

Development and large-scale production of human milk fat analog by fermentation of microalgae

Background

Human milk contains a complex mixture of triacylglycerols (TAG), making it challenging to recreate using common ingredients.

Objective

The study aimed to develop an innovative fermentation technique to produce essential human milk TAG, effectively tackling a significant hurdle in infant nutrition.

Method

An in-depth analysis of the literature has been conducted to identify the specific TAG to be targeted. We used a microalgal oil production platform and a two-step procedure to modify its fatty acid and TAG composition. The palmitic acid (16:0) content has been increased by classical strain improvement techniques, followed by a step involving the expression of a lysophosphatidic acid acyltransferase (LPAAT) sequence capable of esterifying 16:0 specifically at the internal position (sn-2 palmitate) of TAG. Once the strain was stabilized, the fermentation was scaled up in a 50-L reactor to yield several kilograms of biomass. Subsequently, the oil was extracted and refined using standard oil processing conditions. Liquid chromatography-mass spectrometry was employed to monitor the TAG profile and the region specificity of 16:0 at the internal position (sn-2 palmitate) of TAG.

Results

The initial strain had a 16:0 level of 25% of total fatty acids, which was increased to 30% by classical strain improvement. Simultaneously, the oleic acid level decreased from 61% to 57% of total fatty acids. Upon expression of an exogenous LPAAT gene, the level of the 16:0 esterified in the internal position of the TAG (sn-2 palmitate) increased by a factor of 10, to reach 73% of total palmitic acid. Consequently, the concentration of oleic acid in the internal position decreased from 81% to 22% of total fatty acids, with TAG analysis confirming that the primary TAG species in the oil was 1,3-dioleoyl-2-palmitoyl-glycerol (OPO). The 50-L-scale fermentation trial confirmed the strain's ability to produce oil with a yield of >150 g of oil per liter of fermentation broth in a timeframe of 5 days, rendering the process scalable for larger-scale industrialization.

Conclusion

We have demonstrated the feasibility of producing a suitable TAG composition that can be effectively integrated into the formulations of infant nutrition in combination with other fats and oils to meet the infant feeding requirements.

Safety evaluation of INFAT® PLUS: Acute, genetic, teratogenic, and subchronic (90-day) toxicity studies

INFAT®PLUS, is a sn-2 palmitate enriched fat ingredient intended for infant formula. A battery of toxicological studies was conducted in accordance with the Food Safety Toxicological Assessment GB-15193 (China), to confirm the safety of INFAT®PLUS. In the acute oral toxicity test, the LD50 of INFAT® PLUS was higher than 53.4 g /kg BW and 26.7 g/kg BW for ICR mice and SD rats, respectively. In a subchronic study, INFAT® PLUS was administered by oral gavage to SD rats with maximal daily dose of 8.90 g/kg BW for 90 days. No treatment-related clinical signs or mortalities were observed. The no-observed-adverse-effect level (NOAEL) was set at 8.90 g/kg BW. Similarly, no evidence of genotoxicity effect was noted in several in vitro and in vivo tests, including bacterial reverse mutation (Ames) test, mouse erythrocyte micronucleus test, and chromosome aberration test of mouse spermatogonia/spermatocyte. For the teratogenic evaluations, no toxicological signs were observed in both pregnant SD rat and fetuses, and the NOAEL of INFAT® PLUS was determined to be 8.90 g/kg BW. Based on the obtained results we concluded that INFAT® PLUS was found non-toxic under the experimental conditions, and the totality of the safety data supports its use for infant nutrition.

Progress of Mass Spectrometry-Based Lipidomics in the Dairy Field

Lipids play important biological roles, such as providing essential fatty acids and signaling. The wide variety and structural diversity of lipids, and the limited technical means to study them, have seriously hampered the resolution of the mechanisms of action of lipids. With advances in mass spectrometry (MS) and bioinformatic technologies, large amounts of lipids have been detected and analyzed quickly using MS-based lipidomic techniques. Milk lipids, as complex structural metabolites, play a crucial role in human health. In this review, the lipidomic techniques and their applications to dairy products, including compositional analysis, quality identification, authenticity identification, and origin identification, are discussed, with the aim of providing technical support for the development of dairy products.

The Impact of Linoleic Acid on Infant Health in the Absence or Presence of DHA in Infant Formulas

Both linoleic acid (LA) and α-linolenic acid (ALA) are essential dietary fatty acids, and a balanced dietary supply of these is of the utmost importance for health. In many countries across the globe, the LA level and LA/ALA ratio in breast milk (BM) are high. For infant formula (IF), the maximum LA level set by authorities (e.g., Codex or China) is 1400 mg LA/100 kcal ≈ 28% of total fatty acid (FA) ≈ 12.6% of energy. The aims of this study are: (1) to provide an overview of polyunsaturated fatty acid (PUFA) levels in BM across the world, and (2) to determine the health impact of different LA levels and LA/ALA ratios in IF by reviewing the published literature in the context of the current regulatory framework. The lipid composition of BM from mothers living in 31 different countries was determined based on a literature review. This review also includes data from infant studies (intervention/cohort) on nutritional needs regarding LA and ALA, safety, and biological effects. The impact of various LA/ALA ratios in IF on DHA status was assessed within the context of the current worldwide regulatory framework including China and the EU. Country averages of LA and ALA in BM range from 8.5-26.9% FA and 0.3-2.65% FA, respectively. The average BM LA level across the world, including mainland China, is below the maximum 28% FA, and no toxicological or long-term safety data are available on LA levels > 28% FA. Although recommended IF LA/ALA ratios range from 5:1 to 15:1, ratios closer to 5:1 seem to promote a higher endogenous synthesis of DHA. However, even those infants fed IF with more optimal LA/ALA ratios do not reach the DHA levels observed in breastfed infants, and the levels of DHA present are not sufficient to have positive effects on vision. Current evidence suggests that there is no benefit to going beyond the maximum LA level of 28% FA in IF. To achieve the DHA levels found in BM, the addition of DHA to IF is necessary, which is in line with regulations in China and the EU. Virtually all intervention studies investigating LA levels and safety were conducted in Western countries in the absence of added DHA. Therefore, well-designed intervention trials in infants across the globe are required to obtain clarity about optimal and safe levels of LA and LA/ALA ratios in IF.

Profile of Human Milk Phospholipids at Different Lactation Stages with UPLC/Q-TOF-MS: Characterization, Distribution, and Differences

Human milk phospholipids are important for the regular growth and development of infants. Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was employed to qualitatively and quantitatively analyze 277 phospholipid molecular species in 112 human milk samples to obtain a detailed profile of human milk phospholipids along the lactation stage. MS/MS fragmentation patterns of sphingomyelin, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine were characterized in detail. Phosphatidylcholine is the most dominant group, followed by sphingomyelin. PC(18:0/18:2), SM(d18:1/24:1), PE(18:0/18:0), PS(18:0/20:4), and PI(18:0/18:2) showed the highest average concentration among all of the phosphatidylcholine, sphingomyelin, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol molecular species, respectively. The fatty acids attached to the phospholipid molecules were mainly palmitic, stearic, oleic, and linoleic acids, and the plasmalogens decreased along the lactation stage. The increase of sphingomyelins and phosphatidylethanolamines and the decrease of phosphatidylcholines are the key changes from colostrum to transitional milk; the increase of lysophosphatidylcholines and lysophosphatidylethanolamines and the continuous decrease of phosphatidylcholines are the vital changes from transitional milk to mature milk.

A new frontier for fat: dietary palmitic acid induces innate immune memory

Dietary saturated fats have recently been appreciated for their ability to modify innate immune cell function, including monocytes, macrophages, and neutrophils. Many dietary saturated fatty acids (SFAs) embark on a unique pathway through the lymphatics following digestion, and this makes them intriguing candidates for inflammatory regulation during homeostasis and disease. Specifically, palmitic acid (PA) and diets enriched in PA have recently been implicated in driving innate immune memory in mice. PA has been shown to induce long-lasting hyper-inflammatory capacity against secondary microbial stimuli in vitro and in vivo, and PA-enriched diets alter the developmental trajectory of stem cell progenitors in the bone marrow. Perhaps the most relevant finding is the ability of exogenous PA to enhance clearance of fungal and bacterial burdens in mice; however, the same PA treatment enhances endotoxemia severity and mortality. Westernized countries are becoming increasingly dependent on SFA-enriched diets, and a deeper understanding of SFA regulation of innate immune memory is imperative in this pandemic era.

Ostrich oil as a fat substitute in milk-based infant formula

In this study, the possibility of replacing vegetable fats with ostrich oil in infant formula (IF) production was investigated. The fatty acid profile, the positional distribution of fatty acids in the triacylglycerols, the cholesterol content, and the physicochemical properties of ostrich oil were determined and compared with breast milk fat and vegetable oils. In the next step, two infant formulas were produced using ostrich oil and vegetable oils and the physicochemical properties, rheological properties, color parameters, and sensory analysis of the resultant powders were compared. The results showed that the predominant fatty acids in ostrich oil are palmitic acid, oleic acid, and linoleic acid which is similar to breast milk fat and vegetable oils. The presence of appropriate cholesterol content in ostrich oil makes it more similar to breast milk fat compared to vegetable fats. Palmitic acid was located at sn-2 position in 15% triacylglycerol from ostrich fat, which was equal to the amount reported for vegetable fats. The incorporation of ostrich oil in infant formula production showed that there is no statistically significant difference between quality attributes of powder formulated with ostrich oil or vegetable oils. Therefore, ostrich oil can be introduced as a new source of edible oil, and addition of ostrich oil is an effective way to reduce the gap between the composition of breast milk and infant formula.

Lipid Profiles of Human Milk and Infant Formulas: A Comparative Lipidomics Study

Infant formulas (IFs) are prevalent alternatives for human milk (HM), although their comparative lipid profiles have not been fully investigated. We adopted lipidomics to analyze and compare in-depth the lipid patterns of HM and IFs. The results indicated that the distribution of fatty acids (FAs) and the structure of triacylglycerols varied substantially in the analyzed samples. A total number of 425 species were identified during the analysis. HM was abundant in triacylglycerols that contained unsaturated and long-chain FAs (>C13), while triacylglycerols in IFs were mainly comprised of saturated and medium-chain FAs (C8-C13). Higher levels of sphingomyelin were observed in HM. Furthermore, HM and IF1 contained 67 significantly differential lipids (SDLs), and 73 were identified between HM and IF2. These SDLs were closely associated with nine metabolic pathways, of which the most significant was the glycerophospholipid metabolism. The results shed light on the differences between the lipid profiles of human and infant formula milks, and provide support for designing Chinese infant formula.

Evaluation of Fatty Acid Distributions and Triacylglycerol Species in Sow Milk and Commercial Piglet Formulas: A Comparative Study Based on Fat Sources and Lactation Stages

Total fatty acid and sn-2 fatty acid compositions, and triacylglycerol (TAG) species in 130 sow colostrum, 100 sow milk, and 22 piglet formula samples were analyzed in the present study. Significant differences were found in concentrations of medium chain-saturated fatty acids (MC-SFAs) and distributions of palmitic acid (P) and oleic (O)/linoleic (L) acid. The levels of MC-SFAs in sow colostrum and sow milk fats (2.4-3.1%) were significantly lower than those in piglet formulas (7.9-27.2%). Approximately 63% of palmitic acid was located at the sn-2 position in both sow colostrum and milk fats, which was significantly higher than in piglet formula fats (21.1-39.1%). Correspondingly, only 17.8-28.3% of oleic and linoleic acids were at the sn-2 position in sow milk fats, contributing to their typical triacylglycerol structure in sow colostrum and milk, whose palmitic acid connected to the sn-2 position and unsaturated fatty acids located at the sn-1,3 positions. Sow colostrum, milk, and piglet formulas were notably distinguished into three groups based on their fatty acids and TAGs, among which triacylglycerols were the most differentiated index. A total of 51 TAG species (including their isomers) differed significantly between sow colostrum and milk and piglet formulas. OPL and OPO were the most important differentiating TAGs. The large amount of sn-2 esterified palmitic acid plays a key role in improving the absorption of fat and calcium. The results provide suggestions for design of sow milk fat equivalents.

Spectral Analysis and Antiulcer Potential of Lactuca sativa through the Amelioration of Proinflammatory Cytokines and Apoptosis Markers

The objective of this study was to characterize the bioactive ingredients and antiulcer effects of Lactuca sativa leaves. Several bioactive chemicals were found in the cold methanolic extract of Lactuca sativa leaves after gas chromatography-mass spectrometry (GC-MS) research: 9,12-octadecadienoic acid (Z,Z)-, cyclononasiloxane, octadecamethyl-, n-hexadecanoic acid, Hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl)ethyl, octadecanoic acid, 2-hydroxy-1-(hydroxymethyl)ethyl ester, 9-octadecenamide, (Z)-, hexadecanoic acid, stigmasterol, benzothiazole, ethyl iso-allocholate, and octacosane. Distinct fingerprint regions in GCMS indicated the existence of bioactive compounds. The leaf powder of Lactuca sativa (LPL) demonstrated substantial antiulcer properties at 400 mg/kg, which was almost equivalent to the standard drug at 20 mg/kg. The cytokine network was efficiently regulated by reducing the production of proinflammatory cytokines such as IL-1β, IL-6, and TNF-α. The levels of caspase-3 and caspase-9 were also considerably lowered at p < 0.05 significant level.

Fatty acid profile characterization in colostrum, transition milk, and mature milk of primi- and multiparous cows during the first week of lactation

The specific fatty acid (FA) profile of colostrum may indicate a biological requirement for neonatal calves. The objective of this study was to characterize the FA profile and yields in colostrum, transition milk, and mature milk in primiparous (PP) and multiparous (MP) cows. Colostrum was milked from 10 PP and 10 MP Holstein cows fed the same pre- and postpartum rations. Milkings (M) 2 to 5 and 12 were respectively termed transition and mature milk. Overall, short-chain FA (C4:0 and C6:0) were 61 and 50% lower in colostrum than mature milk, respectively. A parity by milking interaction was also present, with higher C4:0 for PP cows at M2 and for MP cows at M12. Additionally, higher concentrations of C6:0 were present for PP cows at M2 through M4 and for MP cows at M12. Palmitic (C16:0) and myristic (C14:0) acids were 38% and 19% higher in colostrum than mature milk, respectively. However, total saturated FA remained relatively stable. Branched-chain FA were 13% lower in colostrum than mature milk and higher in PP than MP cows throughout the milking period. The proportion of trans-monounsaturated FA (MUFA) was 72% higher in PP cows throughout the milking period, as well as 13% lower in colostrum than mature milk. In contrast, cis-MUFA and total MUFA were not affected by milking nor parity. Linoleic acid (LA) was 25% higher in colostrum than transition and mature milks, but α-linolenic acid (ALA) did not differ. Consequently, the ratio of LA to ALA was 29% higher in colostrum than mature milk and 33% higher in MP cows. Linoleic acid was also 15% higher in MP cows, whereas ALA was 15% higher in PP cows. Conjugated linoleic acid (CLA, cis-9,trans-11) was 2.7-fold higher in PP cows, and no differences between colostrum and mature milk were detected. Overall, polyunsaturated FA (PUFA) from the n-6 and n-3 series were over 40% higher in colostrum compared with transition and mature milk. Milking by parity interactions were present for arachidonic acid (ARA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), and total n-3 PUFA, translating to higher proportions in PP cows in M1 to M3, whereas proportions remained relatively stable throughout the milking period in MP cows. Despite increasing milk yields throughout the subsequent milkings, higher yields of EPA, ARA, DPA, and DHA were present in colostrum than in mature milk. Greater proportions and yields of n-3 and n-6 FA in colostrum may translate to specific requirements for newborn calves. Differences were also observed between PP and MP cows and may reflect different nutrient requirements and partitioning.

Functional Significance of Different Milk Constituents in Modulating the Gut Microbiome and Infant Health

Human milk, the gold standard for optimal nourishment, controls the microbial composition of infants by either enhancing or limiting bacterial growth. The milk fat globule membrane has gained interest in gut-related functions and cognitive development. The membrane proteins can directly interact with probiotic bacteria, influencing their survival and adhesion through gastrointestinal transit, whereas membrane phospholipids increase the residence time of probiotic bacteria in the gut. The commensal bacteria in milk act as the initial inoculum in building up the gut colonization of an infant, whereas oligosaccharides promote proliferation of beneficial microorganisms. Interestingly, milk extracellular vesicles are also involved in influencing the microbiota composition but are not well-explored. This review highlights the contribution of different milk components in modulating the infant gut microbiota, particularly the fat globule membrane, and the complex interplay between host- and brain-gut microbiota signaling affecting infant and adult health positively.

A Survey to Identify the Current Management of Cow’s Milk Disorders and the Role of Goat Milk-Based Formulas in the Middle East and North Africa Region

Background: Cow’s milk allergy (CMA) and cow’s milk intolerance (CMI) are the major cow’s milk disorders observed in infants and young children. This study investigates, for the first time, physician knowledge regarding CMA and CMI prevalence, diagnosis, and management in the Middle East and North Africa (MENA) region. In addition, we explore the role of goat milk-based formula as an alternative in infants suffering from CMI. Method: This cross-sectional survey was conducted from December 2020 to February 2021. A convenience sample of 2500 MENA-based physicians received the questionnaire, developed by a working group of pediatric experts. Results: 1868 physicians completed the questionnaire, including pediatric specialists (80.8%), training physicians (0.2%), dermatologists (0.1%), family/general physicians (12.9%), neonatologists (3.6%), neurosurgeons (0.2%), allergy nurse specialists (0.3%), pharmacists (2.1%), and public health workers (0.1%). Differentiation between CMA and CMI was recognized by the majority of respondents (80.7%), for which the majority of respondents (35.4%) identified that the elimination and challenge test was the best test to differentiate CMA from CMI, whereas 30.7% and 5.4% preferred the immunoglobulin E (IgE) test and skin prick test, respectively. In addition, 28.5% of respondents reported that there is no confirmatory test to differentiate CMA from CMI. The majority of respondents (47.3%) reported that amino acid-based formula (AAF)/ extensively hydrolyzed formula (EHF) is the cornerstone for the management of CMA. However, most respondents (33.7%) reported that lactose avoidance was best for the management of CMI. Overall, 65% of the respondents were aware of nutritionally adapted goat’s milk formula as an alternative to cow’s milk products and 37% would recommend its routine use in infants (≤2 years of age). Conclusion: The results of this survey demonstrate that the majority of physicians are aware of the underlying pathophysiology and management of CMA and CMI. However, a significant proportion of physicians do not follow the clinical guidelines concerning CMA/CMI diagnosis and management. Notably, this survey identified that goat’s milk formulas may offer a suitable alternative to AAF/EHF in infants with CMI as they contain β-casein protein which is easily digestible. In addition, goat’s milk formulas contain higher levels of oligosaccharides and medium-chained fatty acids compared with standard cow’s milk formulas, yet further clinical trials are warranted to support the inclusion of goat’s milk formulas in clinical guidelines.

Fatty acid profile characterization in colostrum, transition milk, and mature milk of primi- and multiparous cows during the first week of lactation

The specific fatty acid (FA) profile of colostrum may indicate a biological requirement for neonatal calves. The objective of this study was to characterize the FA profile and yields in colostrum, transition milk, and mature milk in primiparous (PP) and multiparous (MP) cows. Colostrum was milked from 10 PP and 10 MP Holstein cows fed the same pre- and postpartum rations. Milkings (M) 2 to 5 and 12 were respectively termed transition and mature milk. Overall, short-chain FA (C4:0 and C6:0) were 61 and 50% lower in colostrum than mature milk, respectively. A parity by milking interaction was also present, with higher C4:0 for PP cows at M2 and for MP cows at M12. Additionally, higher concentrations of C6:0 were present for PP cows at M2 through M4 and for MP cows at M12. Palmitic (C16:0) and myristic (C14:0) acids were 16% and 27% higher in colostrum than mature milk, respectively. However, total saturated FA remained relatively stable. Branched-chain FA were 13% lower in colostrum than mature milk and higher in PP than MP cows throughout the milking period. The proportion of trans-monounsaturated FA (MUFA) was 42% higher in PP cows throughout the milking period, as well as 15% lower in colostrum than mature milk. In contrast, cis-MUFA and total MUFA were not affected by milking nor parity. Linoleic acid (LA) was 13% higher in colostrum than transition and mature milks, but α-linolenic acid (ALA) did not differ. Consequently, the ratio of LA to ALA was 23% higher in colostrum than mature milk and 25% higher in MP cows. Linoleic acid was also 13% higher in MP cows, whereas ALA was 15% higher in PP cows. Conjugated linoleic acid (CLA, cis-9,trans-11) was 63% higher in PP cows, and no differences between colostrum and mature milk were detected. Overall, polyunsaturated FA (PUFA) from the n-6 and n-3 series were over 25% higher in colostrum compared with transition and mature milk. Milking by parity interactions were present for arachidonic acid (ARA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), and total n-3 PUFA, translating to higher proportions in PP cows in M1 to M3, whereas proportions remained relatively stable throughout the milking period in MP cows. Despite increasing milk yields throughout the subsequent milkings, higher yields of EPA, ARA, DPA, and DHA were present in colostrum than in mature milk. Greater proportions and yields of n-3 and n-6 FA in colostrum may translate to specific requirements for newborn calves. Differences were also observed between PP and MP cows and may reflect different nutrient requirements and partitioning.

Acceptability of "High sn-2" Infant Formula in Non-Breast Fed Healthy Term Infants Regarding Gastrointestinal Tolerability by Both Parents and Pediatrician: An Open-Label Pilot Study in the Gulf Cooperation Council (GCC) Countries

Recent studies have highlighted the positive impact of high sn-2 formulas on gastrointestinal (GI) tolerance. We assessed the GI tolerance, acceptability, and safety of high sn-2 infant formula among non-breastfed healthy term infants in the Gulf countries. A multicenter observational study was conducted on 227 healthy-term infants who were prescribed high sn-2 palmitate infant formula and received a minimum of two formula feedings per day for the past two weeks prior to the study's initiation. The number of stools per day decreased significantly from a median of four (interquartile range [IQR] = 4) at baseline to 3.0 (2) stools per day at the end of follow-up (p = 0.015). The percentage of stool amount changed significantly, where 61.2% and 33.7% of the infants had an amount of 25-50% of the diaper and >50% of the diaper, respectively (p < 0.001) at the end of the follow-up. Similarly, the percentage of hard stool decreased significantly from 17.4% at baseline to 0.4% of the population at week 12 (p < 0.00). The prevalence of colic and abdominal distention declined from 21.4% and 39.9% at baseline to 2.9% and 9.4% at week 12, respectively (p < 0.05). The same decline was observed in abdominal distension and regurgitation score (p < 0.05).

Regio-distribution and double bond locations of unsaturated fatty acids in phospholipids of bovine milk

Hundreds of phospholipid (PL) species with defined fatty acid (FA) composition have been identified previously in bovine milk using liquid chromatography tandem mass spectrometry (LC-MS/MS). Paterno-Buchi photochemical reaction coupled with LC-MS/MS was applied in this study to further unravel the regio-distribution and double bond (DB) locations of FAs. Using SPE-purified PLs and 2-acetylpyridine as the photochemical derivatization reagent, we were able to reveal the non-specific regio-distribution of unsaturated FAs and the widespread occurrence of regioisomers in milk PLs. Although Δ9 and Δ9,12 were found to be the predominant DB location(s) for C18:1 and C18:2 respectively, other DB positional isomers such as C18:1Δ11, C18:1Δ12 and C18:1Δ13 and C18:2Δ9,11 were widely detected in PL structures, implying that the minor isomers of C18:1 and C18:2 equally participate in the synthesis of PLs. Our study provides novel information on the fine structure of milk PLs and further underlines the complexity of milk lipid composition.

Bovine Milk Triacylglycerol Regioisomer Ratio Shows Remarkable Inter-Breed and Inter-Cow Variation

Regioisomers (or positional isomers) of triacylglycerols (TAGs) of milk are known to show differential outcome in relation to human absorption. Quantitation of TAG regioisomers remains a big challenge due to the lack of facile chromatographic separation technique. The feasibility of using fragment ion intensity ratio to determine the ratio of co-eluting AAB/ABA-type regioisomer pairs was confirmed in this study. The ability of C30 stationary phase in resolving interfering TAG isomers was demonstrated for the first time. This allowed us to reveal the complexity of using fragment ion intensity to quantify 1,2-olein-3-palmitin (OOP), 1,3-olein-2-palmitin (OPO), 1,2-olein-3-stearin (OOS), and 1,3-olein-2-stearin (OSO) regioisomers in milk samples. A novel algorithm was proposed to consider the contribution of OPO/OOP and OSO/OOS double bond (DB)-isomers and to eliminate the interference of isobaric ions from other isomers, an aspect overlooked in previous studies. This liquid chromatography-mass spectrometry method that requires no pre-fractioning and a moderate chromatographic separation time of 36 min is simple and, thus, suitable for screening a large number of samples for genetic analysis of this trait. Preliminary results using a small cohort of animals showed that OPO/OOP ratio differs significantly between Jersey and Holstein cows, and a large variation was also observed across individual Holstein cows.

The effect of calcium palmitate on bacteria associated with infant gut microbiota

Gut microbiota development in formula-fed and breast-fed infants is known to differ. This could relate to the usage of unmodified vegetable oil instead of mammalian fat in infant formula (IF), causing the enhanced formation of the poorly soluble soap calcium palmitate (CP) in the infant's gut. Here we investigate in vitro the possible influence of CP on the infant gut bacteria. The growth of several bacterial species dominant in the infant's gut was analyzed by culturing in media with CP. Faecalibacterium prausnitzii as a sensitive representative was analyzed in detail by scanning transmission electron microscopy, membrane staining, gas chromatography, and microbial fuel cell experiments. Of all bacteria tested, the growth of several bifidobacteria and F. prausnitzii was reduced at 0.01 mg/ml CP, Bifidobacterium infantis stopped growing completely. CP reduced the cell envelope thickness of F. prausnitzii, disturbed the cell membrane fatty acids and function of membrane proteins involved in electron transport. CP inhibited the growth of bifidobacteria and faecalibacteria. This suggests that modification of fat in IF may benefit the development of the gut microbiota in formula-fed infants by supporting the colonization of important beneficial bacteria in early life. Future clinical studies are needed to confirm this.

Impact of an Infant Formula Containing a Novel Fat Blend (Cow's Milk Fat, Fish and Vegetable Oil) and Prebiotics on Stool Fatty Acid Soaps and Erythrocyte Fatty Acid Profiles in Full-Term Healthy Newborns

INTRODUCTION

Recently, new commercial infant formulas have been composed considering novel fat blends and oligosaccharides to better resemble the fatty acid (FA) composition and stereospecific distribution (e.g., increased amount of ß-palmitate) as well as probiotics content of human breast milk. We hypothesized that these newly composed infant formulas may decrease fecal FA soap excretion and may positively affect erythrocyte FA profiles compared with regular formulas.

METHODS

Healthy infants were randomly assigned to receive a high-sn-2-palmitate formula (>25% of the PA is esterified to the sn-2 position of the glycerol backbone, verum: n = 30) or a "standard" formula containing <10% of PA in sn-2 position and no oligosaccharides (control: n = 27); a non-randomized group of breast-fed infants served as control. Anthropometric data of the infants (body weight, recumbent length, and head circumference) were recorded at inclusion (visit 1) and 6 and 12 weeks after onset of intervention (visits 2 and 3). Blood samples for erythrocyte FA analysis (gas chromatography) were taken at visits 1 and 2; stool samples were collected at visit 2.

RESULTS

Quantitative formula intake (mL/kg body weight × day) at visit 2 (verum: 155 ± 30, control: 164 ± 30) and visit 3 (verum: 134 ± 26, control: 134 ± 21) was comparable. Six weeks after onset of intervention, stool total FA soaps, palmitate soaps, and total FAs were similar in both formula-fed groups but significantly higher than in breast-fed infants. During the 6-week intervention, erythrocyte palmitate decreased significantly from baseline in all 3 groups with no group differences (verum: 29.20 ± 1.17 to 27.12 ± 0.66, control: 29.88 ± 2.00 to 27.01 ± 0.94, breast-fed: 30.20 ± 0.86 to 26.84 ± 0.98). For selected FAs, significant changes over time in verum and control group were obvious but without formula effects. Some variations in the FA profile of breast-fed infants compared to both verum and control groups were observed.

CONCLUSIONS

In contrast to our hypothesis, feeding a newly composed infant formula based on a fat blend with 25% of PA in the sn-2 position of triacylglycerols and supplemented with a prebiotic could not decrease insoluble FA soap excretion compared with a standard product; in this respect, breastfeeding is obviously the best choice. Surprisingly, erythrocyte FA profiles were comparable in formula-fed and breast-fed infants; obvious alterations in FA composition of the respective fat sources and structure did not affect FA incorporation into membranes. Caution should be, however, exercised in drawing robust conclusions in the absence of larger, adequately powered intervention studies.

Total and Sn-2 Fatty Acid Profile in Human Colostrum and Mature Breast Milk of Women Living in Inland and Coastal Areas of China

INTRODUCTION

Although lipid is the major energy source and exerts beneficial effects on infant growth, research on the composition of fatty acid (FA) at the sn-2 position of human milk (HM) in China and abroad is limited.

OBJECTIVES

This study aimed to investigate the FA positional distribution in colostrum and mature HM of women living in the inland and coastal areas of China and explore the potential influences of geographical region and lactation stage on the FA profile of Chinese women.

METHODS

Colostrum milk (n = 61) and mature milk (n = 56) samples were obtained longitudinally from healthy lactating women in Guangzhou and Chengdu, China. Gas chromatography was used to determine the total and sn-2 FA composition.

RESULTS

Significant differences were observed in the FA profile of HM between different regions and lactation stages, with differences in polyunsaturated FA levels being the most pronounced. Nearly 70% of sn-2 FAs were saturated FAs, of which C16:0 accounted for approximately 75%. C8:0, C10:0, C18:0, C20:0, C22:0, and all of the unsaturated FAs were mainly located at the sn-1 and sn-3 positions, while C14:0, C15:0, and C16:0 were mainly at the sn-2 position. The proportion of C12:0 and C17:0 at sn-2 was approximately equivalent to that at the sn-1, 3 positions.

CONCLUSIONS

The results indicate the variability in the FA profile of HM between regions and lactation stages. The contents of polyunsaturated FAs and sn-2 FAs, especially palmitic acid, should be paid more attention when optimizing infant formula.

Lipid Composition, Digestion, and Absorption Differences among Neonatal Feeding Strategies: Potential Implications for Intestinal Inflammation in Preterm Infants

Necrotizing enterocolitis (NEC) is a significant cause of morbidity and mortality in the neonatal population. Formula feeding is among the many risk factors for developing the condition, a practice often required in the cohort most often afflicted with NEC, preterm infants. While the virtues of many bioactive components of breast milk have been extolled, the ability to digest and assimilate the nutritional components of breast milk is often overlooked. The structure of formula differs from that of breast milk, both in lipid composition and chemical configuration. In addition, formula lacks a critical digestive enzyme produced by the mammary gland, bile salt-stimulated lipase (BSSL). The gastrointestinal system of premature infants is often incapable of secreting sufficient pancreatic enzymes for fat digestion, and pasteurization of donor milk (DM) has been shown to inactivate BSSL, among other important compounds. Incompletely digested lipids may oxidize and accumulate in the distal gut. These lipid fragments are thought to induce intestinal inflammation in the neonate, potentially hastening the development of diseases such as NEC. In this review, differences in breast milk, pasteurized DM, and formula lipids are highlighted, with a focus on the ability of those lipids to be digested and subsequently absorbed by neonates, especially those born prematurely and at risk for NEC.

Stool Saponified Fatty Acid, Behavior, Growth, and Stool Characteristics in Infants Fed a High-OPO Formula: A Randomized, Double-Blind Clinical Trial

Objective: 1,3-Dioleoyl-2-palmitoylglycerol (OPO) is an ideal structured triglyceride for infant formula, with a similar structure to human milk fat. We conducted this randomized, double-blind controlled, single-center trial to evaluate the effects of an OPO formula in infants. Study Design: One hundred seventy-four healthy term infants <14 days old were assigned to the standard formula-fed group (n = 55), high sn-2 palmitic acid (OPO) formula-fed infants (n = 58), and breastfed (BF) group (n = 61). The primary endpoint was the total saponified fatty acid content in feces at week 6 and week 12. Results: Infants from the OPO group had lower concentrations of fecal saponified fatty acids than those from the standard formula group (p < 0.0001) at week 6 and week 12. The frequencies of crying per day and per night of infants in the OPO group were significantly less than those of infants in the standard formula group (p < 0.0001). After 12 weeks of feeding, the length of infants was significantly higher in the OPO group than in the other two groups (p = 0.002). Infants in the OPO group had a significantly lower stool calcium concentration and a higher stool frequency per day than infants in the standard formula group. Conclusion: In summary, a high concentration of OPO in formula is beneficial to the growth and development of infants.

Effect of milk fat-based infant formulae on stool fatty acid soaps and calcium excretion in healthy term infants: two double-blind randomised cross-over trials

Background

Palmitic acid (PA) is predominantly esterified at the SN-2 position of triacylglycerols in human milk. PA at the SN-2 position is more efficiently absorbed and results in reduced formation of PA soaps, as well as reduced fatty acid (FA) and calcium malabsorption. Bovine milk fat (MF), a natural source of SN-2-palmitate, was used in the fat blend of infant formulae (IF) in the current study to investigate its effect on stool fatty acid soaps, calcium excretion and stool characteristics.

Methods

Two double-blind, randomised cross-over trials (CS1, CS2) were conducted in parallel with healthy term, formula-fed infants aged 9-14 weeks. After a two-week run-in period, infants in CS1 (n = 17) were randomly allocated to receive either a 50% MF-based formula (50MF) or a 100% vegetable fat (VF) formula; in CS2 (n = 18), infants received either a 20% MF-based formula (20MF) or the VF formula, in a 2 × 2-week cross-over design. At the end of each two-week intervention period, stool samples were collected for FA, FA soaps and calcium excretion analysis and stool consistency was assessed according to the Amsterdam Infant Stool Scale (AISS).

Results

MF-based groups showed no significant difference in PA in stools compared to VF group, although reduced stool PA soaps (CS1: 111.28 ± 18.33 vs. 220.25 ± 29.35 mg/g dry weight, p < 0.0001; CS2: 216.24 ± 25.16 vs. 233.94 ± 35.12 mg/g dry weight, p = 0.0023), total FA soaps and calcium excretion (CS1: 46.40 ± 5.27 vs. 49.88 ± 4.77 mg/g dry weight, p = 0.0041; CS2: 46.20 ± 4.26 vs. 50.47 ± 6.71 mg/g dry weight, p = 0.0067) were observed. Furthermore, the 50MF group showed a favourable lower mean stool consistency score compared to the VF group (1.64 ± 0.49 vs. 2.03 ± 0.19, p = 0.0008).

Conclusions

While the use of bovine MF in IF did not affect PA concentrations in stool, lower excretion of palmitate soaps, total FA soaps and calcium was seen in healthy term infants. 50MF formula also showed improved stool consistency. The use of MF in IF could be an interesting approach to improve gut comfort and stool characteristics in infants, warranting further research.

Trial registration

Netherlands Trial Registry Identifier: NTR6702. Date registered: December 01, 2017.

Infant formula with cow's milk fat and prebiotics affects intestinal flora, but not the incidence of infections during infancy in a double-blind randomized controlled trial

Background

The postnatal intestinal colonization of human milk-fed and formula-fed infants differs substantially, as does the susceptibility to infectious diseases during infancy. Specific ingredients in human milk, such as prebiotic human milk oligosaccharides and a specifically structured fat composition with high proportion of beta-palmitic acid (beta-PA) promote the growth of intestinal bifidobacteria, which are associated with favorable effects on infants’ health. The present study investigates whether addition of prebiotic galactooligosaccharides (GOS) in combination with higher amounts of beta-PA from cow’s milk fat in infant formula positively affects gut microbiota and the incidence of infections in formula-fed infants.

Methods

In a double-blind controlled trial, formula-fed infants were randomly assigned to either receive an experimental formula containing a higher proportion of beta-PA (20–25%) from natural cow’s milk fat, and a prebiotic supplement (0.5 g GOS/100 ml), or a standard infant formula with low beta-PA (< 10%), without prebiotics. A breast-fed reference group was also enrolled. After 12 weeks, fecal samples were collected to determine the proportion of fecal bifidobacteria. The number of infections during the first year of life was recorded.

Results

After 12 weeks, the proportion of fecal bifidobacteria was significantly higher in infants receiving formula with high beta-PA and GOS compared to control, and was similar to the breast-fed group (medians 8.8%, 2.5%, and 5.0% respectively; p < 0.001). The incidence of gastrointestinal or other infections during the first year of life did not differ between groups.

Conclusions

The combination of higher amounts of beta-PA plus GOS increased significantly the proportion of fecal bifidobacteria in formula-fed infants, but did not affect the incidence of infections.

Trial registration

The study protocol was registered with Clinical Trials (Protocol Registration and Results System Trial ID: NCT01603719) on 05/15/2012 (retrospectively registered).

Effect of Calcium Treatment on Catabolic Rates of 13C-Labeled Fatty Acids Bound to the α and β Positions of Triacylglycerol

The absorption efficacies and catabolic rates of fatty acids are affected by their binding position on triacylglycerol (TAG). However, the kind of effect calcium treatment has on the catabolism of fatty acids is unclear. In this study, the catabolic rates of ¹³C-labeled palmitic acid, oleic acid, and linoleic acid bound to sn-1, 3 (α) and sn-2 (β) position of TAG in the presence of calcium were compared using isotope ratio mass spectrometry. The catabolic rates of ¹³C-labeled fatty acids were evaluated using the ratio of ¹³C to ¹²C in the carbon dioxide expired by mice. The catabolic rate of palmitic acid bound to the α position was significantly lower than that of palmitic acid bound to the β position of TAG. The rates of ¹³CO₂ formation from palmitic acid at the β position remained higher for a long time. In contrast, oleic and linoleic acids at the α position were as well catabolized as those at the β position. These results indicate that in the presence of calcium, the saturated fatty acid bound to the β position is highly catabolized, whereas that bound to the α position is not well catabolized. Saturated fatty acid at the α position is hydrolyzed by pancreatic lipase to promptly form insoluble complexes with calcium, which are excreted from the body, and thereby reducing the catabolic rate of these fatty acids.

Palm Oil and Beta-palmitate in Infant Formula: A Position Paper by the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) Committee on Nutrition

BACKGROUND

Palm oil (PO) is used in infant formulas in order to achieve palmitic acid (PA) levels similar to those in human milk. PA in PO is esterified predominantly at the SN-1,3 position of triacylglycerol (TAG), and infant formulas are now available in which a greater proportion of PA is in the SN-2 position (typical configuration in human milk). As there are some concerns about the use of PO, we aimed to review literature on health effects of PO and SN-2-palmitate in infant formulas.

METHODS

PubMed and Cochrane Database of Systematic Reviews were systematically searched for relevant studies on possible beneficial effects or harms of either PO or SN-2-palmitate in infant formula on various health outcomes.

RESULTS

We identified 12 relevant studies using PO and 21 studies using SN-2-palmitate. Published studies have variable methodology, subject characteristics, and some are underpowered for the key outcomes. PO is associated with harder stools and SN-2-palmitate use may lead to softer stool consistency. Bone effects seem to be short-lasting. For some outcomes (infant colic, faecal microbiota, lipid metabolism), the number of studies is very limited and summary evidence inconclusive. Growth of infants is not influenced. There are no studies published on the effect on markers of later diseases.

CONCLUSIONS

There is insufficient evidence to suggest that PO should be avoided as a source of fat in infant formulas for health reasons. Inclusion of high SN-2-palmitate fat blend in infant formulas may have short-term effects on stool consistency but cannot be considered essential.

Lipid Profiling, Particle Size Determination, and in Vitro Simulated Gastrointestinal Lipolysis of Mature Human Milk and Infant Formula

Dairy technologists has attempted to produce "improved" infant formulas mimicking human milk by supplementation with bovine MFGM and/or phospholipids-enriched materials. The present study investigated and compared the lipid profile and particle sizes of mature human milk and infant formula fat globules (IF 1, IF 2, IF 3, and IF 4) and elucidated the relationship between physicochemical properties and in vitro simulated gastrointestinal lipolysis rate of the different milk samples. Despite having larger micron-sized fat globules, mature human milk demonstrated the highest gastrointestinal lipolysis rate with higher release of medium- and long-chain saturated fatty acids. In comparison, IF 3, which contained the lowest phospholipids content, demonstrated the lowest gastrointestinal lipolysis rate. Higher gastrointestinal lipolysis rate of mature human milk fat as compared to infant formula fats might be due to the presence of MFGM interfacial layer (phospholipids) surrounding the fat droplets which govern lipase activity on lipid droplets.

Human milk enriched with human milk lyophilisate for feeding very low birth weight preterm infants: A preclinical experimental study focusing on fatty acid profile

BACKGROUND

Human milk, with essential nutrients and long chain polyunsaturated fatty acids (LC-PUFAs) such as the omega 3 and 6 fatty acids is important for development of the central nervous system and the retina in very low birth weight infants (<1,500 g). However, breast milk may not be sufficient to meet these needs. The possibility of supplementing breast milk with a lyophilisate of human milk was explored in this study. The objectives of this study were to determine the total lipid content and the lipid profile of the Human Milk on Baseline (HMB) and that of the Concentrates with the Human Milk + lyophilisate (with lyophilisate of milk in the immediate period (HMCI), at 3 months (HMC3m), and at 6 months (HMC6m) of storage).

METHODS

Fifty donors from the Human Milk Bank of Children's Hospital provided consent, and donated milk samples. Macronutrient (including total lipids) quantification was performed using the MIRIS® Human Milk Analyzer, and the fatty acid profile was determined by gas chromatography (CG-FID, SHIMADZU®).

RESULTS

There was a higher lipid concentration in HMCI relative to HMB. The concentrations of the main fatty acids (% of total) were as follows: palmitic acid (C16:0) HMB, 22.30%; HMCI, 21.46%; HMC3m, 21.54%; and HMC6m, 21.95% (p<0.01); oleic acid (C18:1n-9) HMB, 30.41%; HMCI, 30.47%; HMC3m, 30.55%; and HMC6m, 29.79% (p = 0.46); linoleic acid (C18:2n-6) HMB, 19.62%; HMCI, 19.88%; HMC3m, 19.49%; and HMC6m, 19.45% (p = 0.58); arachidonic acid (C20:4n-6) HMB, 0.35%; HMCI, 0.16%; HMC3m, 0.13%; and HMC6m, 0.15% (p<0.01); α-linolenic acid (C18:3n-3) HMB,1.32%; HMCI, 1.37%; HMC3m, 1.34%; and 1.34% HMC6m (p = 0.14); docosahexaenoic acid (C22:6n-3) HMB, 0.10%; HMCI, 0.06%; HMC3m, 0.05%; and HMC6m, 0.06% (p<0.01). There were no significant changes in the lipid profile when stored. There was no evidence of peroxidation during storage.

CONCLUSIONS

Freeze-dried human milk fortified with a human milk concentrate brings potential benefits to newborns, mainly by preserving the essential nutrients present only in breast milk; however, further clinical studies are required to evaluate the safety and efficacy of the concentrate as a standard nutritional food option for very low birth weight infants.

Association between sn-2 fatty acid profiles of breast milk and development of the infant intestinal microbiome

Increasing evidence shows that host diet and gut microbes are related. Previous studies have shown the effects of specific dietary fatty acids (FAs) on intestinal microbiota, but little is known about the effect of the stereospecifically numbered sn-2 position in triglycerides (TG) of human milk on the gut microbiome of infants. This study aimed at examining possible effects of sn-2 FAs of human milk on the gut microbial development of breastfeeding babies. Sn-2 FAs and intestinal microbiota were assessed by GC-MS and high-throughput 16S rRNA sequencing, respectively. The results showed that breast milk from mothers in China contained ten major sn-2 FAs dominated by palmitic acid (C_16:0, 54.42%), oleic acid (C_18:1 n-9, 14.95%), linoleic acid (LA, C_18:2 n-6, 12.81%), myristic acid (C_14:0, 4.50%) and C_12:0 (3.17%). Total long chain unsaturated fatty acids (LCUFA) decreased from colostrum to mature milk, while total saturated fatty acids (SFA) showed no significant difference during lactation. A significant association between sn-2 FAs in milk and infant gut microbiota was found between decanoic acid (C_10:0), myristic acid (C_14:0), stearic acid (C_18:0), C_16:0, arachidonic acid (AA, C_20:4 n-6), docosahexaenoic acid (DHA, C_22:6 n-3) with Bacteroides, Enterobacteriaceae, Veillonella, Streptococcus, and Clostridium. These microbes were involved in short-chain fatty acid (SCFA) production and other functions, and significantly increased at 13-15 d after breastfeeding was initiated. C_16:0 and DHA were relevant to most of the microbes. This study demonstrated the relatively steady profiles of sn-2 FAs in breast milk and gut microbiota of infants, together with their correlation during the breastfeeding period. The above results provided important information for designing the configuration of FAs in next-generation formulas for Chinese infants.

No effect of adding dairy lipids or long chain polyunsaturated fatty acids on formula tolerance and growth in full term infants: a randomized controlled trial

Background

When breastfeeding is not possible, infants are fed formulas in which lipids are usually of plant origin. However, the use of dairy fat in combination with plant oils enables a lipid profile in formula closer to breast milk in terms of fatty acid composition, triglyceride structure and cholesterol content. The objectives of this study were to investigate the impact on growth and gastrointestinal tolerance of a formula containing a mix of dairy lipids and plant oils in healthy infants.

Methods

This study was a monocentric, double-blind, controlled, randomized trial. Healthy term infants aged less than 3 weeks whose mothers did not breastfeed were randomly allocated to formula containing either: a mix of plant oils and dairy fat (D), only plant oils (P) or plant oils supplemented with long-chain polyunsaturated fatty acids (PDHA). Breastfed infants were included in a reference group (BF). Anthropometric parameters and body composition were measured after 2 and 4 months. Gastrointestinal tolerance was evaluated during 2 day-periods after 1 and 3 months thanks to descriptive parameters reported by parents. Nonrandomized BF infants were not included in the statistical analysis.

Results

Eighty eight formula-fed and 29 BF infants were enrolled. Gains of weight, recumbent length, cranial circumference and fat mass were similar between the 3 formula-fed groups at 2 and 4 months and close to those of BF. Z-scores for weight, recumbent length and cranial circumference in all groups were within normal ranges for growth standards. No significant differences were noted among the 3 formula groups in gastrointestinal parameters (stool frequency/consistency/color), occurrence of gastrointestinal symptoms (abdominal pain, flatulence, regurgitation) or infant’s behavior.

Conclusions

A formula containing a mix of dairy lipids and plant oils enables a normal growth in healthy newborns. This formula is well tolerated and does not lead to abnormal gastrointestinal symptoms. Consequently, reintroduction of dairy lipids could represent an interesting strategy to improve lipid quality in infant formulas.

Trial registration

ClinicalTrials.gov Identifier NCT01611649, retrospectively registered on May 25, 2012.

Evaluation of sn-2 fatty acid composition in commercial infant formulas on the Chinese market: A comparative study based on fat source and stage

The sn-2 fatty acid composition of 180 commercial infant, follow-on and growing-up formulas with three fat sources (plant oil, cows' milk and goats' milk) was investigated and compared with mature human milk (MHM). Sn-2 fatty acids in formulas were mostly dependent on fat source and stage. Compared with MHM, all types of formulas contained lower levels of palmitic acid (PA), saturated fatty acid and long-chain polyunsaturated fatty acids (LC-PUFA), and higher levels of oleic acid (OA), linoleic acid (LA) and α-linolenic acid (LNA) at the sn-2 position. Even some formulas were supplemented with 1,3-dioleoyl-2-palmitoylglycerol, the proportions of relative PA at the sn-2 position in formulas were much lower than that in MHM. Moreover, formulas had higher proportions of relative OA, LA and LNA, and lower LC-PUFAs at the sn-2 position. This study indicated that there were significant differences in the positional distribution of fatty acids between formulas and MHM.

Beta Palmitate Improves Bone Length and Quality during Catch-Up Growth in Young Rats

Palmitic acid (PA) is the most abundant saturated fatty acid in human milk, where it is heavily concentrated in the sn-2-position (termed beta palmitate, BPA) and as such is conserved in all women, regardless of their diet or ethnicity, indicating its physiological and metabolic importance. We hypothesized that BPA improves the efficiency of nutrition-induced catch up growth as compared to sn-1,3 PA, which is present in vegetable oil. Pre-pubertal male rats were subjected to a 17 days food restriction followed by re-feeding for nine days with 1,3 PA or BPA-containing diets. We measured bone length, epiphyseal growth plate height (EGP, histology), bone quality (micro-CT and 3-point bending assay), and gene expression (Affymetrix). The BPA-containing diet improved most growth parameters: humeri length and EGP height were greater in the BPA-fed animals. Further analysis of the EGP revealed that the hypertrophic zone was significantly higher in the BPA group. In addition, Affymetrix analysis revealed that the diet affected the expression of several genes in the liver and EGP. Despite the very subtle difference between the diets and the short re-feeding period, we found a small but significant improvement in most growth parameters in the BPA-fed rats. This pre-clinical study may have important implications, especially for children with growth disorders and children with special nutritional needs.

Which dietary components modulate longitudinal growth?

PURPOSE OF REVIEW

Linear growth in children is sensitive to nutritional status; the growth of the human skeleton requires many different nutritional factors for energy and building blocks: proteins, lipids, carbohydrates and micronutrients. However, what are the specific nutritional factors that are required for proper growth and what is the composition that will be most beneficial is still not known.

RECENT FINDINGS

Recent findings indicate that macro and micronutrients are required as building blocks and as cofactors for important enzymes. In addition, they stimulate linear growth by acting as regulatory factors and also affect gut microbiome. Some interesting studies regarding the effect of proteins and amino acids are presented.

SUMMARY

Most studies investigated the effect of replacing a single micronutrient that was deficient; however, in real life, deficiency of one nutritional element is commonly associated with other deficiencies. Therefore, it is a reasonable clinical approach, both in developing and developed countries, to use a mixture of both macro and micronutrients to support growth. How much of each of the components and what is the best composition are still open questions that require more research.