Evaluating the Potential of Methyl Jasmonate Application as an Agricultural Practice on Phytochemicals in Brassica Vegetables: Sensory Quality, Cooking, and Cost-Benefit Analysis

In the United States, Brassica vegetables, including broccoli (Brassica oleracea var. italica) and kale (Brassica oleracea var. acephala or Brassicae napus var. pabularia), are widely consumed and are easily accessible in farmer’s market or grocery stores with increasing interest of their health-promoting properties. For example, the consumption of broccoli has been associated with anti-cancer activity in in vitro and in vivo trails due to the high content of phytochemicals, minerals, vitamins, and fibers. Application of methyl jasmonate (MeJA) has been reported to enhance the potential health-promoting compounds in Brassica vegetables, glucosinolates (GS), especially indolyl GS neoglucobrassicin are induced by mimicking insect damage because MeJA activates herbivory defense system. Although exogenous MeJA application has been recognized as a method to simulate insect herbivory and to invoke downstream defense mechanisms (inducing GS accumulation), only limited studies investigating the difference in metabolite changes or transcription level changes between two treatments in Brassica species. In Chapter 2, the metabolomic and transcriptomic changes between insect damage (4 days treatment of cabbage looper caterpillars) were compared. The primary result indicated levels of gene expression changes are slightly different between two treatments while the metabolite changes were similar but in different levels. For example, significantly increased indolyl GS was found in both treatments but higher in insect feeding groups. GS loss during the cooking process has been intensively reported in Brassica vegetables; however, there is limited research on whether MeJA application affects GS retention after different cooking methods while MeJA application significantly increases inducible GS in Brassica vegetables. In Chapter 3, the phytochemical profile change after three different cooking methods (boiling, steaming, and microwaving) and two cooking times (2 and 5 minutes) on control and MeJA-treated broccoli. Among six cooking treatments (methods x times), 5 minutes boiling led to the most significant loss in total aliphatic (22%) and indole GS (62%) in control while it caused 47% total aliphatic and 54% indole GS loss in MeJA-treated broccoli; however, MeJA-treated broccoli contained 1.9-fold higher GS than the untreated broccoli after 5 min of boiling, which was considered the most drastic treatment in this study. These changes by exogenous MeJA application, including GS level, GS hydrolysis products level, and primary metabolites, may alter the sensorial attributes of Brassica vegetables. Therefore, MeJA application may impact consumer acceptance and sensorial quality of Brassica vegetables, and the degree of impact may depend on level of myrosinase activation during cooking. In Chapter 4, an untrained consumer panel detected the differences between raw control and 250 µM MeJA treated broccoli; however, four minutes of steaming eliminated the detectable bitterness in MeJA-treated broccoli and the consumer panel could not detect the difference between control and MeJA-treated broccoli. Neoglucobrassicin-derived hydrolysis products, N-methoxyindole-3-carbinol, N-methoxyindolyl-3-carboxaldehyde, and N-methoxyindole-3-acetonitrile, were the most important metabolites in determining the overall liking and the taste of broccoli samples using partial least square regression model. After 4 min steaming, MeJA-treated broccoli still contained 7.8-fold more neoglucobrassicin and 50% more total GS than untreated broccoli Despite all the positive results of exogenous MeJA application on Brassica vegetables, the applicability of this practice is limited without further evaluations on the feasibility from the consumers as well as from the growers. In Chapter 5, the consumer survey suggested that consumers who considered “anticancer broccoli” as the most attractive trait may be the potential customers who were willing to pay higher price ($1.00 or$1.50 more per broccoli head) for MeJA-treated broccoli; however, recruited growers from the local farmer’s market were concerned about the detectable bitterness in raw MeJA-treated broccoli would deter consumers from buying their broccoli in the future. Exogenous MeJA application may bring extra gross income for growers with small-scale broccoli production when we hypothesized a scenario from a very small farm (acre) when the elasticity of vegetable was set at -0.58 or-0.79. Collectively, the results from this project implied that exogenous MeJA treatment (mimicking insect herbivory) on Brassica vegetables has its potential for use in the food industry and in the right market’s niche. For example, MeJA-treated broccoli can be used as an ingredient to boost the nutrition quality and/or as a value-added ingredient in precooked meals because cooked MeJA-treated broccoli contained a higher level of GS comparing to cooked untreated broccoli. Therefore, exogenous MeJA application may be more suitable to the farms providing Brassica vegetables directly to the food processing industry instead of the farms selling fresh produce directly to the consumers

Family Needs and Family Quality of Life for Taiwanese Families of Children with Intellectual Disability and Developmental Delay

This dissertation consists of four related chapters including an introductory overview of all four chapters, a report on family needs, a report on family quality of life, and a summary of implications for the conceptual framework. Chapter 1, the introductory overview, presents background information of Taiwan and describes the family quality of life conceptual framework as the context of the research. It further summarizes information in chapters 2 to 4. Using descriptive and ANOVA results from a survey study, Chapter 2 investigates family quality of life - the outcome in the conceptual framework. Chapter 3, on the other hand, addresses family needs - the input factor in the conceptual framework. Based on findings from the previous two chapters, Chapter 4 revisits the conceptual framework and discusses the relationship between family needs and outcomes

Glucosinolates, Carotenoids, and Vitamins E and K Variation from Selected Kale and Collard Cultivars

Glucosinolates, carotenoids, and fat-soluble vitamins E and K contents were analyzed from various kale and collard cultivars at mature stage. We found a significant difference in these phytonutrients among cultivars. Among kale cultivars, “Beira” and “Olympic Red” were the highest in the total glucosinolate and “Toscano” kale was the highest in total carotenoid content. “Scarlet” kale was highest in tocopherols. For collard, total glucosinolate was the highest in “Top Bunch” while carotenoids were the highest in “Green Glaze.” An accession PI261597 was the highest in phylloquinone. In addition to the total content of each phytonutrient class, their composition differed among cultivars, indicating that each cultivar may have differential regulatory mechanisms for biosynthesis of these phytonutrients. Our result indicates that cultivar selection may play an important role in consumption of kale and collard with greater nutritional benefit. Therefore, the result of this study will provide a more thorough profile of essential and nonessential phytonutrients of kale and collard cultivars for consumers’ choice and for future research on nutritional value of these crops

Targeted Metabolomic and Transcriptomic Analyses of “Red Russian” Kale (Brassicae napus var. pabularia) Following Methyl Jasmonate Treatment and Larval Infestation by the Cabbage Looper (Trichoplusia ni Hübner)

Methyl jasmonate (MeJA), synthesized in the jasmonic acid (JA) pathway, has been found to upregulate glucosinolate (GS) biosynthesis in plant species of the Brassicaceae family. Exogenous application of MeJA has shown to increase tissue GS concentrations and the formation of myrosinase-mediated GS hydrolysis products (GSHPs). In vitro and in vivo assays have demonstrated the potential health-promoting effects of certain GSHPs. MeJA is also known to elicit and induce genes associated with defense mechanisms to insect herbivory in Brassica species. To investigate the relationship between MeJA-induced GS biosynthesis and insect defense, three treatments were applied to “Red Russian” kale (Brassicae napus var. pabularia) seedlings: (1) a 250 μM MeJA leaf spray treatment; (2) leaf infestation with larvae of the cabbage looper (Trichoplusia ni (Hübner)); (3) control treatment (neither larval infestation nor MeJA application). Samples of leaf tissue from the three treatments were then assayed for changes in GS and GSHP concentrations, GS gene biosynthesis expression, and myrosinase activity. Major differences were observed between the three treatments in the levels of GS accumulation and GS gene expression. The insect-damaged samples showed significantly lower aliphatic GS accumulation, while both MeJA and T. ni infestation treatments induced greater accumulation of indolyl GS. The gene expression levels of CYP81F4,MYB34, and MYB122 were significantly upregulated in samples treated with MeJA and insects compared to the control group, which explained the increased indolyl GS concentration. The results suggest that the metabolic changes promoted by MeJA application and the insect herbivory response share common mechanisms of induction. This work provides potentially useful information for kale pest control and nutritional quality

Compact Dual-Band Dipole Antenna with Asymmetric Arms for WLAN Applications

A dual-band dipole antenna that consists of a horn- and a C-shaped metallic arm is presented. Depending on the asymmetric arms, the antenna provides two −10 dB impedance bandwidths of 225 MHz (about 9.2% at 2.45 GHz) and 1190 MHz (about 21.6% at 5.5 GHz), respectively. This feature enables it to cover the required bandwidths for wireless local area network (WLAN) operation at the 2.4 GHz band and 5.2/5.8 GHz bands for IEEE 802.11 a/b/g standards. More importantly, the compact size (7 mm × 24 mm) and good radiating performance of the antenna are profitable to be integrated with wireless communication devices on restricted RF-elements spaces