Influence of Plant Origins and Seasonal Variations on Nutritive Values, Phenolics and Antioxidant Activities of Adenia viridiflora Craib., an Endangered Species from Thailand

Exploration of the nutritional and carotenoids profiles of vegetables in Thai cuisine as potential nutritious ingredients

Missing information on plant origin control and nutritional data on herbs, spices and vegetables could lead to sample quality deficit and misusage of the plant database. In this study, twenty vegetables that were collected and managed based on the recommendations of the Department of Agriculture, Ministry of Agriculture and Cooperatives, Thailand, were investigated regarding their proximate mineral, vitamin and carotenoid contents using the standard procedures of the Association of Official Analytical Chemists (AOAC). The results showed that these plants (100 g dry weight) exhibited similar energy levels (337.11-420.48 kcal), which were mainly distributed from high carbohydrate content (21.01-88.17 g), while protein (3.14-66.07 g) and fat (0.00-10.33 g) levels were quite low. As a form of carbohydrate, dietary fiber was found to be high in Cymbopogon citratus (DC.) Stapf (Cy. citratus) and Solanum torvum Sw. (So. torvum) (57.00-59.54 g). Interestingly, Senegalia pennata subsp. insuavis (Lace) Maslin, Seigler & Ebinger (S. pennata) exhibited exceptionally high protein content, which was between 2.3 and 3.1 times higher than its carbohydrates. High mineral contents were detected in S. pennata, Ocimum africanum Lour. (O. africanum), Ocimum basilicum L. (O. basilicum), Ocimum gratissimum L. var. macrophyllum Briq. (O. gratissimum) and Coriandrum sativum L. (Co. sativum), while Mentha cordifolia Opiz ex Fresen (M. cordifolia) was observed to be a good source of vitamin C (381.36-547.47 mg). High carotenoids were mostly found in Eryngium foetidum L. (E. foetidum), O. gratissimum, Co. sativum and O. basilicum (75.23-119.96 mg). Interestingly, the location of sample collection seemed to have minimal effect on the nutritional and carotenoid compositions. The results of this study provide reliable information concerning the nutritional and carotenoid contents in plant sources with control of origin, which could be used in the future for food development with specific nutritional requirements.

Seasonal Effects on Phenolic Contents and In Vitro Health-Promoting Bioactivities of Sacred Lotus (Nelumbo nucifera)

Sacred lotus (Nelumbo nucifera) is a commercial product in Asian countries. Almost all parts of the lotus plant are consumed as food or used as traditional medicine due to their high contents of secondary metabolites such as phenolics and alkaloids. However, agricultural management of the sacred lotus occurs during the rainy season, and the plant enters a resting stage during the dry season. Thus, seasonal variation (beginning, middle and end of the rainy season) was investigated for total phenolic contents (TPCs), antioxidant capacities and inhibitions of the key enzymes relevant to chronic diseases including Alzheimer's disease (β-secretase, acetylcholinesterase and butyrylcholinesterase), hypertension (angiotensin-converting enzyme), obesity (lipase) and diabetes (α-glucosidase) of different sacred lotus parts (seed embryo, petal, stamen, old leaf, leaf stalk and flower stalk). Results indicated that an aqueous extract of stamen in all harvesting seasons exhibited potentially high TPCs, which led to high antioxidant activities and most enzyme inhibitions (up to 53.7-fold higher) than the others collected in the same harvesting period. The phenolic content and biochemical activities in stamen harvested at the beginning of the rainy season were up to 4-fold higher than during other harvesting periods. This information benefits the agricultural management of sacred lotus and supports consumption of different sacred lotus parts for health promotion. Results can be used as an initial database for future product development from different sacred lotus parts.

Improvement of Sourdough and Bread Qualities by Fermented Water of Asian Pears and Assam Tea Leaves with Co-Cultures of Lactiplantibacillus plantarum and Saccharomyces cerevisiae

Qualities of sourdough and sourdough bread using fermented water from Asian pears and Assam tea leaves with Lactiplantibacillus plantarum 299v and Saccharomyces cerevisiae TISTR 5059 as starter cultures were evaluated. Changes in the growth of lactic acid bacteria and yeast, pH, sourdough height, total phenolic contents (TPCs) and antioxidant activities detected by ORAC, FRAP and DPPH radical scavenging assays were monitored during sourdough production. Mature sourdough was achieved within 4 h after 18 h retard fermentation and used for bread production. The bread was then analyzed to determine chemical and physical properties, nutritional compositions, TPCs, antioxidant activities and sensory properties as well as shelf-life stability. Results showed that fermented water significantly promoted the growth of yeast and increased TPCs and antioxidant activities of sourdough. Compared to common sourdough bread, fermented water sourdough bread resulted in 10% lower sugar and 12% higher dietary fiber with improved consumer acceptability; TPCs and antioxidant activities also increased by 2–3 times. The fermented water sourdough bread maintained microbial quality within the standard range, with adequate TPCs after storage at room temperature for 7 days. Fermented water from Asian pears and Assam tea leaves with L. plantarum 299v and S. cerevisiae TISTR 5059 as starter cultures improved dough fermentation and bread quality.