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Sweet corn is frequently consumed in the US and contains carbohydrates as major macronutrients. This study examined the effects of blanching, freezing, and canning on carbohydrates in sweet corn. Fresh bi-color sweet corn was picked in the field and processed immediately into frozen and canned samples. Simple sugars, starch, and dietary fiber (DF) (including total DF (TDF), insoluble DF (IDF) and two fractions of soluble DF (SDF)) were measured according to the AOAC methods. Additional glycomic analysis including oligosaccharides, monosaccharide composition of total polysaccharides (MCTP) and glycosidic linkage of total polysaccharides (GLTP) were analyzed using UHPLC-MS. Sucrose is the major simple sugar, and IDF is the main contributor to TDF. Sucrose and total simple sugar concentrations were not altered after blanching or freezing but were significantly reduced in canned samples. Kestose was the only oligosaccharide identified in sweet corn and decreased in all heat-treated or frozen samples. Starch content decreased in frozen samples but increased in canned samples. While two SDF fractions did not differ across all samples, blanching, freezing and canning resulted in increases in TDF and IDF. Six monosaccharides were identified as major building blocks of the total polysaccharides from MCTP analysis. Glucose and total monosaccharide concentrations increased in two canned samples. GLTP was also profoundly altered by different food processing methods. This study provided insights into the changes in the content and quality of carbohydrates in sweet corn after food processing. The data are important for accurate assessment of the carbohydrate intake from different sweet corn products. [ABSTRACT FROM AUTHOR]

The effects of genotype (G), growing environment (E), and their interactions (G × E) on the phytochemical compositions and radical scavenging properties of wheat bran were investigated using ten soft winter wheat ( Triticum aestivum L.) varieties grown in four locations. In general, E had stronger influence on the selected health beneficial components and antioxidant properties of soft winter wheat brans than G or G × E ( P < 0.001). E had a strong impact on α-tocopherol, δ-tocopherol, total tocopherols, total phenolic content (TPC), total soluble ferulic acid, and ABTS + cation and DPPH radical scavenging capacities ( P < 0.001). The results also showed that each soft wheat bran component or radical scavenging property may respond to individual environmental factors differently. For the first time, the present study showed that E, G, and G × E differed in their effects on the selected health components and antioxidant properties of soft red winter wheat bran. [ABSTRACT FROM AUTHOR]

A total of 13 commercial soybean samples were investigated and compared for their tocopherol and carotenoid compositions, fatty acid profile, total phenolic content (TPC), isoflavone and sterol compositions, and free radical scavenging properties. Free radical scavenging activities were estimated against peroxyl, hydroxyl, and ABTS(•) (+) radicals. The commercial soybean samples differed in their chemical compositions and health properties. Among the tested samples, CN-DB soybean showed the highest TPC and antioxidant activities and the greatest amount of total isoflavones and lutein and tocopherol contents. In addition, four of the soybean samples were further tested for their potential anti-inflammatory activity. The four samples behaved differently in suppressing the IL-1β, IL-6, and COX-2 mRNA expressions, suggesting their different potential of anti-inflammatory activities. The results from this study suggested a need of improved quality control and measurement system to better reflect the health properties of commercial soybeans for general consumers and food manufacturers to improve the use of this important food ingredient.

To determine the possible alternative use of tobacco, the seeds representing seven Maryland tobacco cultivars were investigated for their phytochemical, antioxidant, and antiproliferative properties. Tobacco seed oils were extracted by the Soxhlet method, and analyzed for their yield, density, refractive index, fatty acid profiles, and tocopherol profile. The defatted flours were extracted in 50% acetone and 80% ethanol. The tobacco seed oil and flour extracts were analyzed for total phenolic contents (TPC) and scavenging capacities against peroxyl, hydroxyl and 2,2-diphenyl-1-picryhydrazyl (DPPH) radicals. The fatty acid compositions of phospholipids and the protein content of the flours were also analyzed. In addition, oil and flour extracts of varieties MD609 and MD609LA were evaluated for their antiproliferative effects on HT-29 human colon cancer cells. All of the tested extracts significantly inhibited HT-29 cell proliferation except that from MD609 oil. The data from this study suggest the potential alternative use of tobacco seeds in developing natural antioxidants and antiproliferative agents for improving human health.

A high-throughput assay was developed to detect soybean lipoxygenase 1 (LOX-1) using a multilabel plate reader. The assay was also adapted to a single cell fluorometer. Fluorescein is degraded by linoleic hydroperoxide produced from soybean lipoxygenase and linoleic acid. The decrease in fluorescence is measured over time, and the area-under-the-curve (AUC) is used to quantify the LOX-1 content of soybean extract. A dose-dependent response is seen with varied dilutions of pure LOX enzyme or soybean extracts. Percent recovery was between 97% and 108%, and relative standard deviation was 4.3%. Advantages of the assay include the reduced preparation time of samples and reduced use of reagents in the high-throughput assay. Multiple samples can be measured in a single run with a multilabel plate reader.

Five Gynostemma pentaphyllum (GP) samples were investigated and compared for their chemical compositions and their antioxidant, antiproliferative, and anti-inflammatory effects. Extracts (50% acetone, 75% ethanol, and 100% ethanol) of the five GP samples (GP1-5) differed in their total phenolic, saponin, and flavonoid contents and in their rutin and quercetin concentrations. The highest level of total flavonoids was 63.5 mg of rutin equiv/g in GP4, and the greatest total phenolic content was 44.3 mg of gallic acid equiv/g in GP1 with 50% acetone as the extraction solvent. GP2 had the highest total saponin content of 132.6 mg/g with 100% ethanol as the extraction solvent. These extracts also differed in their scavenging capacity against DPPH and hydroxyl radicals, although they all showed significant radical scavenging capacity. The 100% ethanol extracts also showed dose-dependently strong inhibition on IL-6 and Ptgs2 mRNA expression and weak inhibition on TNF-α mRNA expression. In addition, GP1 had the highest antiproliferative activity at 3.2 mg equiv/mL concentration in HT-29 human colon cancer cells. The results from this study will be used to promote the application of G. pentaphyllum for improving human health.

Eight soybean genotypes grown in three environments in Maryland were analyzed for total phenolic content (TPC), antioxidant capacity, isoflavone composition, lutein, tocopherols, fatty acid composition, and oil content. Fatty acid composition, isoflavones, lutein, tocopherols, and specific antioxidant assays had significant variation by genotype (G) (P < 0.05). Environment (E) had a significant effect on fatty acids, lutein, individual tocopherols, oxygen radical absorbance capacity (ORAC), and the isoflavone glycitein (P < 0.05). In addition, the interaction between genotype and environment (G x E) showed a significant effect on antioxidant capacity, isoflavones, lutein, tocopherols, and fatty acids (P < 0.05). Factorial designed analysis of variance of all data indicated that G had a larger effect than E on the majority of fatty acids, total isoflavones, lutein, and total tocopherols. E had a larger effect than G on stearic acid (18:0), glycitein, delta-tocopherol, and ORAC. The results of this study show that the genotype, growing environment, and their interactions in Maryland-grown soybeans may alter the levels of specific health-enhancing properties.