Incorporation Of Carbohydrates Research Articles

Development of a functional dulce de leche (milk jam) with prebiotic carbohydrates and Lacticaseibacillus rhamnosus GG

A functional dulce de leche (DL) was developed by incorporating prebiotic carbohydrates (inulin and maltodextrin) and probiotic Lacticaseibacillus rhamnosus ATCC 53103 (LGG) (either as free cells, or encapsulated in pectin beads with or without prebiotics). Encapsulation improved the viability of LGG cells in DL during refrigerated storage, and its survival under simulated gastrointestinal conditions. Final cell counts in all DL samples after 6 months were >106 CFU g−1. Incorporation of carbohydrates in DL and probiotic encapsulation state had no significant effect on colour (L∗a∗b∗), rheological and mechanical properties. Although encapsulation state caused a significant effect on acceptability of DL, all samples scored above the minimum acceptability level, with more than 80% of consumers acceptance. Storage time had a significant effect (only after 2–3 months) on DL properties (except b∗ and adhesiveness), causing an increase in rheological properties, a decrease in texture parameters, and a decrease in L∗ and a∗.

Modulation of the gut microbiota by processed food and natural food: evidence from the Siniperca chuatsi microbiome.

Habitual dietary changes have the potential to induce alterations in the host's gut microbiota. Mandarin fish (Siniperca chuatsi), an aquatic vertebrate species with distinct feeding habits, were fed with natural feeds (NF) and artificial feeds (AF) to simulate the effects of natural and processed food consumption on host gut microbiota assemblages. The results showed that the alpha diversity index was reduced in the AF diet treatment, as lower abundance and diversity of the gut microbiota were observed, which could be attributed to the colonized microorganisms of the diet itself and the incorporation of plant-derived proteins or carbohydrates. The β-diversity analysis indicated that the two dietary treatments were associated with distinct bacterial communities. The AF diet had a significantly higher abundance of Bacteroidota and a lower abundance of Actinomycetota, Acidobacteriota, and Chloroflexota compared to the NF group. In addition, Bacteroidota was the biomarker in the gut of mandarin fish from the AF treatment, while Acidobacteriota was distinguished in the NF treatments. Additionally, the increased abundance of Bacteroidota in the AF diet group contributed to the improved fermentation and nutrient assimilation, as supported by the metabolic functional prediction and transcriptome verification. Overall, the present work used the mandarin fish as a vertebrate model to uncover the effects of habitual dietary changes on the evolution of the host microbiota, which may provide potential insights for the substitution of natural foods by processed foods in mammals.

Digestive enzyme activities during pejerrey (Odontesthes bonariensis) ontogeny

The first step for assessing and refining the nutritional requirements during the larval and early juvenile stages of a fish is the study of the ontogeny of digestive system functionality. The combination of these studies with ecological and anatomical knowledge of the species of interest establishes the base for facing one of the major aquaculture challenges: promoting larvae growth and survival. Considering this, changes in the activity of the main digestive (pancreatic and intestinal) enzymes during larval development of the agastric South America pejerrey (Odontesthes bonariensis) were described in the present work. Digestive enzymes for protein, lipid, and carbohydrate hydrolysis were present from the first-week post-hatching (6.85 ± 0.07 mm total length, TL). Changes in the activity of trypsin, chymotrypsin, and alkaline protease indicated that the exocrine pancreas in pejerrey achieves its functional development at the 2nd week post-hatching (9.22 ± 0.17 mm TL). Interestingly, α-amylase and maltase total activity progressively increased over development, suggesting that gradual incorporation of dietary carbohydrates in a feeding protocol may have a protein-sparing effect, as well as a cheap and fast way to obtain energy for the development and growth of pejerrey. The analysis of intestinal enzymes revealed that the typical shift between intracellular and luminal protein digestion that occurs during larval development in gastric species does not take place in pejerrey, indicating that in agastric species intracellular protein digestion plays a major role in comparison to luminal digestion during larval development. Contrary to gastric species, our results suggest that the ratio of alkaline phosphatase to leucine-aminopeptidase for evaluating gut maturation in agastric species is not recommended, and other parameters should be measured when evaluating the maturation process in fish larvae from this group of species.

Protein:Carbohydrate Ratios in the Diet of Gypsy Moth Lymantria dispar Affect its Ability to Tolerate Tannins.

Generalist insect herbivores may regulate nutrient balance in their diets, including the incorporation of carbohydrates as well as proteins. However, secondary metabolites, including tannins, are likely to interact with dietary protein:carbohydrate ratios in insect herbivores. We investigated the effects of protein:carbohydrate ratios, tannin, and the interaction between macronutrient ratios and tannin on the performance of thegypsy moth Lymantria dispar. We designed a 6 X 3 factorial experiment, with six protein:carbohydrate ratios and three tannin concentrations. We monitored the development time and size of gypsy moths on the different diets. We conducted 4th stadium feeding trials to measure consumption, digestibility, and overall efficiency of ingestion/digestion. Gypsy moths fed adiet containing a 1:1 protein:carbohydrate ratio without tannin grew larger and developed faster than those fed a 1:2 protein:carbohydrate ratiodiet. Increasing protein in the diet above the 1:1 protein:carbohydrate ratio (i.e. 2:1 or 7:1) did not have a significant effect on gypsy moth growth or development. Approximate digestibility was greatest in treatments with a low protein:carbohydrate ratio (1:2). Gypsy moths grew faster and larger on no-tannin diets than those with tannin in the diet. However, the specific concentration of tannin did not affect growth. The resulting interaction between protein:carbohydrate ratio and tannin showed that there may be a trade-off between development time and efficiency of food assimilation. We also found that feeding gypsy moth larvae an optimal protein:carbohydrate ratios may be more important for tolerating tannin than the amount of protein ingested alone.

Heat Stress Suppresses Brassica napus Seed Oil Accumulation by Inhibition of Photosynthesis and BnWRI1 Pathway.

Heat stress during Brassica napus seed filling severely impairs yield and oil content. However, the mechanisms underlying heat-stress effects on B. napus seed photosynthesis and oil accumulation remain elusive. In this study, we showed that heat stress resulted in reduction of seed oil accumulation, whereas the seed sugar content was enhanced, which indicated that incorporation of carbohydrates into triacylglycerols was impaired. Photosynthesis and respiration rates, and the maximum quantum yield of photosystem II in developing seeds were inhibited by heat stress. Transcriptome analysis revealed that heat stress led to up-regulation of genes associated with high light response, providing evidence that photoinhibition was induced by heat stress. BnWRI1 and its downstream genes, including genes involved in de novo fatty acid biosynthesis pathway, were down-regulated by heat stress. Overexpression of BnWRI1 with a seed-specific promoter stabilized both oil accumulation and photosynthesis under the heat-stress condition, which suggested BnWRI1 plays an important role in mediating the effect of heat stress on fatty acid biosynthesis. A number of sugar transporter genes were inhibited by heat stress, resulting in defective integration of carbohydrates into triacylglycerols units. The results collectively demonstrated that disturbances of the seed photosynthesis machinery, impairment of carbohydrates incorporation into triacylglycerols and transcriptional deregulation of the BnWRI1 pathway by heat stress might be the major cause of decreased oil accumulation in the seed.

Seasonal variations in the 14C Content of Tree Rings: Influences on Radiocarbon Calibration and Single-Year Curve Construction

AbstractTo examine the implications of seasonality for the construction of a single-year calibration curve we obtained separate dates on earlywood and latewood fractions of tree rings originating from England and dendrochronologically dated between AD 1352 and AD 1442. These demonstrated that an average difference of 26±15 yr exists between earlywood and latewood and that this difference can be as high as 33±19 yr during periods of high radiocarbon (14C) production. It is argued that this difference is due to both changes in atmospheric 14C and the incorporation of stored carbohydrates into earlywood. Based on this, it was possible to separate an atmospheric and physiological contribution to this difference. Our modeling indicates that storage can produce a difference of up to 10 years between earlywood and latewood. This suggests that full-year tree rings from deciduous trees may be less appropriate for the construction of a single-year calibration curve and that specific atmospheric events can be more easily detected by measuring only latewood.

High Molecular Weight Coffee Melanoidins Are Inhibitors for Matrix Metalloproteases

High molecular (above 10 kDa) melanoidins isolated from coffee beans of varying roasting degree were found to be efficient inhibitors for the zinc-containing matrix metalloproteases MMP-1, MMP-2, and MMP-9 with IC(50) values ranging between 0.2 and 1.1 mg/mL in vitro. The inhibitory potential increased with roasting degree. No or only slight inhibition of other zinc-containing peptidases closely related to MMPs, namely, Clostridium histolyticum collagenase and angiotensin converting enzyme, was found, indicating specific structural features of melanoidins to be responsible for the interaction with MMPs. A continuous increase on the apparent molecular weight of melanoidins as well as incorporation of phenolic substances into the melanoidin structure with progress of roasting was observed, concomitant with a significant increase in the carbon/nitrogen of the melanoidins. This suggests that the melanoidins are mainly formed by incorporation of carbohydrates and phenolic compounds onto a proteinaceous backbone. As MMP-1, MMP-2, and MMP-9 play a pivotal role in pathogenesis of colorectal cancer, studies on possible physiological effects of melanoidins are mandatory.

The Signal Peptide of the Ebolavirus Glycoprotein Influences Interaction with the Cellular Lectins DC-SIGN and DC-SIGNR

The C-type lectins DC-SIGN and DC-SIGNR (collectively referred to as DC-SIGN/R) bind to the ebolavirus glycoprotein (EBOV-GP) and augment viral infectivity. DC-SIGN/R strongly enhance infection driven by the GP of EBOV subspecies. Zaire (ZEBOV) but have a much less pronounced effect on infection mediated by the GP of EBOV subspecies. Sudan (SEBOV). For this study, we analyzed the determinants of the differential DC-SIGN/R interactions with ZEBOV- and SEBOV-GP. The efficiency of DC-SIGN engagement by ZEBOV-GP was dependent on the rate of GP incorporation into lentiviral particles, while appreciable virion incorporation of SEBOV-GP did not allow robust DC-SIGN/R usage. Forced incorporation of high-mannose carbohydrates into SEBOV-GP augmented the engagement of DC-SIGN/R to the levels observed with ZEBOV-GP, indicating that appropriate glycosylation of SEBOV-GP is sufficient for efficient DC-SIGN/R usage. However, neither signals for N-linked glycosylation unique to SEBOV- or ZEBOV-GP nor the highly variable and heavily glycosylated mucin-like domain modulated the interaction with DC-SIGN/R. In contrast, analysis of chimeric GPs identified the signal peptide as a determinant of DC-SIGN/R engagement. Thus, ZEBOV- but not SEBOV-GP was shown to harbor high-mannose carbohydrates, and GP modification with these glycans was controlled by the signal peptide. These results suggest that the signal peptide governs EBOV-GP interactions with DC-SIGN/R by modulating the incorporation of high-mannose carbohydrates into EBOV-GP. In summary, we identified the level of GP incorporation into virions and signal peptide-controlled glycosylation of GP as determinants of attachment factor engagement.

The influence of root-zone temperature on growth of Betula pendula Roth.

We have examined shoot and root growth and the concentration of carbohydrates in seedlings of a northern (67°N) and a southern (61°N) ecotype of Betula pendula Roth. cultivated at root-zone temperatures of 2, 6, 12 and 17°C. Three hydroponic experiments were conducted in controlled environments. We used three different pretreatments before seedlings were subjected to the experimental temperature treatments. Actively growing seedlings that were acclimated to the hydroponic solution for 3 weeks at a root temperature of 17°C, continued to grow at all the experimental temperatures, with an expected increase in growth from 2 to 17°C. However, if we started with ecodormant cold stored plants or used seedlings grown actively in perlite, no growth was observed at 2°C and only minor growth was found at 6°C. The highest root temperature always produced the best growth. The concentration of nonstructural carbohydrates was higher in seedlings grown at 2°C than at 17°C, and this is probably due to extensive incorporation of carbohydrates into cell walls and other structural elements at 17°C. We found no evidence for differences between the two ecotypes in root growth, in timing of bud burst, but shoot growth terminated in the northern ecotype in the first experiment because the natural photoperiod was below the critical value. Our study highlights the importance of post-transplantation stress (planting check) related to root growth, and that root threshold temperatures may change according to the way plants are pretreated.

Low-Glycemic Index Carbohydrates

This retrospective study evaluated the incorporation of low-glycemic index (GI) carbohydrates into daily meal planning as an effective behavioral lifestyle change to improve glycemic control and weight management in patients with type 1 and 2 diabetes. Twenty-one subjects participated in this study. All office visits and interview sessions took place in a 2-physician private medical practice setting in Wayne, New Jersey. Patients' pre- and postcounseling HbA1c and body mass index (BMI) values and their antidiabetic medication dosages were recorded. Audiotaped interviews were conducted using the 10-question Glycemic Index Foods Quiz (GIFQ) and the 29-question Interview Questionnaire (IQ). The GI values of pre- and postcounseling meals were calculated. Assessment was based on triangulating the subjects' adherence to the low-GI carbohydrate behavioral change and the primary outcome measures: HbA1c and BMI. Low-GI medical nutrition therapy (LGI-MNT) counseling reduced HbA1c by 19% (mean drop of 1.5 U) and decreased BMI by 8% (mean loss of 17 pounds). This was accomplished by the participants independently lowering the GI values of their meals by 25% (mean reduction of 15 points). Results were achieved over a time frame of 3 to 36 months from the initial LGI-MNT counseling session. Daily incorporation of low-GI carbohydrates in meal planning can be an effective diabetes self-management strategy for glycemic control and weight management. The documented responses to the subjects' conceptual and practical knowledge of the GI confirm their acceptance of this approach as a permanent behavioral lifestyle change and not a "diet." The positive results of this study attest to what worked for these subjects, inviting diabetes educators to consider offering low-GI dietary advice to their diabetes patients.

Functional Polymeric Nanoparticles: An Efficient and Promising Tool for Active Delivery of Bioactives

Nanotechnology is a multidisciplinary field and has achieved breakthroughs in bioengineering, molecular biology, diagnostics, and therapeutics. A recent advance in nanotechnology is the development of a functional nanosystem by incorporation, adsorption, or covalent coupling of polymers, carbohydrates, endogenous substances/ligands, peptides, proteins, nucleic acids, and polysaccharides to the surface of nanoparticles. Functionalization confers a wide array of interesting properties such as stealth characteristics, a bioadhesive property, and that it prevents aggregation of nanoparticles, imparts biostability and solubility, reduces toxicity, and provides site-specific delivery. This makes the nanosystem an intelligent tool for diagnostics, prognostics, and controlled and sustained delivery of protein, peptide, pDNA, and other therapeutic agents to specific targets (tissue, cell, and intracellular). Various types of functional nanosystems, such as carbon nanotubes, quantum dots, polymeric micelles, dendrimers, metallic nanoparticles, and liposomes, are being extensively explored. However, high tissue accumulation of nonbiodegradable nanoparticles has caused toxicity problems and rendered them as not-so-popular therapeutic and diagnostic systems. The toxicity and safety of nonbiodegradable nanoparticles are subject to future research. Polymeric nanoparticles have offered attractive alternative modules due to biocompatibility, nonimmunogenicity, nontoxicity, biodegradability, simple preparation methods, high physical stability, possibility of sustained drug release, and higher probability for surface functionalization. Depending on properties that have been modified, polymeric nanoparticles can be grouped in to four classes, namely, stealth, polysaccharide decorated biomimetic, bioadhesive, and ligand-anchored functional polymeric nanoparticles (f-PNPs). This review explores the ligand-anchored f-PNP as a carrier for active delivery of bioactives, envisaged to date. This review also details the ligands available for conjugation, their method of coupling to nanoparticles, and applications of f-PNPs in anticancer drug delivery, oral delivery, gene delivery, vaccine delivery, and intracellular delivery; site-specific delivery to liver, macrophages, lymphatics, and brain; and miscellaneous applications. This review also addresses formidable challenges encountered, and proposes some future strategies for development of a promising site-specific active delivery system.

Properties of caraway ( Carum carvi L.) essential oil encapsulated into milk protein-based matrices

Encapsulating properties of whey protein concentrate (WPC), skimmed milk powder (SMP), and their mixtures with maltodextrins (MD) for encapsulation of caraway essential oil by spray drying were studied. Encapsulation efficiency (EE) was higher in WPC-based matrices compared to SMP. Partial replacement of WPC by various MD increased the retention of volatiles during spray drying and enhanced protective properties of solidified capsules against oxidation and release of volatiles during storage. The opposite tendency was shown by SMP matrices: adding MD to the wall composition resulted in lower retention of volatiles during drying and lower oxidation stability compared to the SMP and all WPC based matrices. Dynamic headspace analysis (DHS) was applied to determine the rate of release of volatiles from the microencapsulated powders. Results revealed that combined matrices of SMP and carbohydrates had the highest volatile release ratio. Partial replacement of WPC by MD significantly reduced release of volatiles from capsules as determined by DHS. Flavor profile of caraway oil entrapped in the matrix was similar to that of pure essential oil: a small decrease in limonene content was recorded for some matrices. The results of scanning electron microscopy (SEM) of microencapsulated particles showed WPC-based matrices to have less visible cracks and holes compared to SMP. More dented surfaces could be observed in particles containing MD as compared to WPC only. It was concluded that WPC-based matrices were more effective as caraway oil encapsulating agents as compared to those of SMP. The incorporation of carbohydrates to WPC results in obtaining more effective microencapsulants.

Lectin cytochemical characterization of the N- and O-linked oligosaccharides in the human rectum.

The oligosaccharides of the mucus glycoproteins of the human rectum are important for the lubricant and protective role suggested for the rectal mucus. Changes in oligosaccharide composition are observed in several colon diseases, and some of these changes could be used as diagnostic and prognostic indicators. Thus, a previous knowledge of the normal mucus glycoproteins is necessary. The aim of the present study is the characterization of the oligosaccharides of the goblet cells and enterocytes of the human rectum. For this, a battery of 15 lectins, in combination with chemical and enzymatic deglycosylation procedures, was used. Our results suggest the presence of N-acetylglucosamine (GlcNAc), Man, Glc, N-acetylneuraminic acid (Neu5Ac)(alpha2-6)- and Neu5Ac(alpha2-3)-linked, N-acetylgalactosamine (GalNAc) and Gal(beta1-3)GalNAc in the oligosaccharides of the goblet cells. Moreover, N-linked oligosaccharides specifically contained Gal(beta1-4)GlcNAc, while AAA-positive Fuc was only detected in O-linked oligosaccharides. Some of these carbohydrates were only visualized after removal of N- or O-linked oligosaccharides, suggesting a high level of approximation between the oligosaccharide chains, that render the carbohydrate inaccessible to the lectins. Differences in the labelling pattern between the goblet cells of the surface epithelium and the upper half of the crypts, and those of the lower half of the crypts suggests a maturation process for the goblet cells, which modifies the oligosaccharide composition of the secreted glycoproteins, as they ascend throughout the crypts. This maturation process includes the incorporation of new carbohydrates (GlcNAc), and the masking (Neu5Ac(alpha2-3)-linked) or unmasking (Glc and GalNAc) of others.

ChemInform Abstract: Incorporation of Carbohydrates and Peptides into Large Triazine‐Based Screening Libraries Using Automated Parallel Synthesis

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Incorporation of carbohydrates and peptides into large triazine-based screening libraries using automated parallel synthesis

A procedure for the sequential, selective derivatization of cyanuric chloride that allows for the incorporation of carbohydrates and peptides has been elucidated. As a result, large combinatorial arrays of individual derivatives, over 40,000 in all, have been produced in 50μmole quantities using automated parallel solution phase synthesis. The use of this technology in a search for protease inhibitors, glycopeptide surrogates and other bioactive compound classes will also be discussed.

Ethylene effects on cambial activity and cell wall formation in hypocotyls of Picea abies seedlings

Ethylene regulation of cell division in the vascular cambium and cell wall formation was studied in hypocotyls of Norway spruce (Picea abies [L.] Karst.) seedlings. Cuttings from 6‐week‐old seedlings were placed in water culture to which compounds affecting the synthesis and action of ethylene were added. After a 3‐week treatment period, growth, ethylene production, morphology and cell wall composition of the hypocotyls were determined. Addition of high concentrations of the potent ethylene releasing agent 2‐chloroethylphosphonic acid (ethrel), which increased ethylene emission by more than twice compared to control plants, inhibited the expansion of xylem cells while stimulating the incorporation of cell wall material, especially cellulose. Addition of small amounts of ethrel, which slightly stimulated ethylene emission, led to increases in the size of xylem cells, the amount of phloem tissue and the number of intercellular spaces in the cortex, and thus to increased hypocotyl diameter. However, no significant change in cell wall composition was detected. When ethylene production was decreased by adding Co2+ to the nutrient solution, differentiation of new xylem was disturbed, but the rate of cell division was not affected. Although the incorporation of cell wall material was inhibited, the proportions of lignin and cellulose in the wall appeared to remain unchanged. Silver ions stimulated the expansion of both xylem and cortex cells, but had no significant effect on cell wall formation. We conclude that ethylene has a role in regulating the incorporation of wall carbohydrates.

Macrophage (Monocyte)‐Derived Mucous Secretagougue (MMS) is Released into the Fluid of the Middle Ear of Patients with Otitis Media with Effusion

Macrophage (monocyte)-derived secretagogue (MMS) is a low molecular weight peptide released by activated macrophages. This substance can enhance incorporation of carbohydrates into protein and result in the production of glycoproteins. It is believed that increased glycoproteins lead to the increased tenaciousness of mucoid effusions. Sixteen of 28 middle ear effusions demonstrated significant amounts of MMS. It is suggested that MMS is produced by activated macrophages in MEE and may lead to the development of glycoprotein by secretory epithelial cells. This substance may lead to the development of the mucoid effusion in otitis media with effusion in children.

Circulating melanoma-associated antigen detected by monoclonal antibody NKI/C-3.

NKI/C-3 and NKI/black-13 are monoclonal antibodies recognizing different epitopes on a melanoma-associated antigen that is preserved after fixation in formalin and embedding in paraffin in virtually all melanoma tissues. The antigen, a predominantly cytoplasmic vesicle membrane-bound heterogeneous glycoprotein of 25-110 X 10(3) daltons, was shown to be a single 25 X 10(3) dalton polypeptide when incorporation of N-linked carbohydrates was inhibited by tunicamycin. The antigen was measured in a double determinant enzyme immunoassay (DDEIA) using NKI/C-3 as catcher antibody. Results from in vitro experiments indicated that the antigen is actively shed from living cells. In sera from melanoma patients with a small tumor burden, the antigen concentrations were in the range of those of controls (0-22 U/ml). Significantly increased values (33-600 U/ml) were found in sera from patients with a moderate or large tumor burden. The antigen concentrations in sera from patients with multiple metastases of other tumors were within the range of controls. Several sera from patients with multiple metastases of colon, pancreatic, and stomach carcinoma, however, contained increased antigen concentrations (45-80 U/ml). These results correspond with the reactions of NKI/C-3 in tissue sections of some malignancies other than melanoma. During the follow-up of melanoma patients the concentrations of circulating antigen correlated with tumor progression. The predictive value of the NKI/C-3 assay was no better than determination of serum lactate dehydrogenase, alkaline phosphatase or gamma glutamyl transferase activity.

Uptake and incorporation of 14C-labelled carbohydrates in the tissues of the reproductive system of the female fowl

1. 1. The in vivo incorporation of radioactivity from [ 14C]GlcN, [ 14C]GalN, [ 14C]Glc and [ 14C]Gal, for different time intervals between 1 and 240 hr into whole tissues, acetone extracted tissues and MPS-P of the different parts of the reproductive system of the female fowl was studied. 2. 2. The incorporation of radioactivity was more extensive when [ 14C]GlcN was injected than when [ 14C]GalN was injected. 3. 3. The incorporation of radioactivity was much more extensive when [ 14C]HexN was injected than when the corresponding [ 14C]Hex was injected. This difference of incorporation was greater in the MPS-P than in the fresh or acetone extracted tissues. 4. 4. A comparison was undertaken in the extent that radioactivity was incorporated among the different parts of the reproductive system of the fowl when [ 14C]HexN and 14C[Hex] were administered.

Distribution of carbohydrate residues in normal skin.

Sections of biopsies of normal skin obtained from 11 individuals were incubated with 8 lectins using an avidin-biotin complex (ABC). All sections when incubated with the appropriate lectin showed the presence of the following carbohydrate residues: L-fucose, beta-(1-4)-D-GlcNAc)2 (N-acetylglucosamine), acetylneuraminic acid, Gal-beta-(1-3)-GalNAc (N-acetyl-galactosamine), beta-D-galactose, alpha-D-glucose, and alpha-D-mannose. In addition, sections of individuals with blood group A showed alpha-D-GalNAc and sections of individuals with blood group B showed alpha-D-galactose. In the stratum (str.) basale, carbohydrates were present in small quantities, but as the cells matured and moved upward, the incorporation of carbohydrates into the cell membranes increased considerably. In the str. granulosum, lectin reactivity was absent in many sections, probably due to masking by phospholipids. The dark cells in the eccrine glands showed reactivity with all lectins except in the one nonsecretor with blood group A1, whose dark cells showed no L-fucose and alpha-D-GalNAc. The endothelial cells of the blood vessels showed lectin reactivity except when incubated with concanavalin A. The sebaceous glands showed both cytoplasmic and membrane staining when incubated with various lectins.