Microgreens are young and tender leafy vegetables that have gained wider consumer acceptance. This is attributed to their low caloric composition and rich micronutrient and antioxidant composition. The present study investigated the bioactive composition and proximate analysis of fourteen microgreens belonging to Brassicaceae, Fabaceae, Pedaliaceae, Polygonaceae, Convolvulaceae, and Malvaceae. All the microgreens showed low calories (20.22 to 53.43 kcal 100 g−1) and fat (0.15 to 0.66 g 100 g−1), whilst mung bean and lentil microgreens showed considerable amounts of carbohydrate (7.16 g 100 g−1) and protein (6.47 g 100 g−1), respectively. Lentil microgreens had the highest total chlorophyll (112.62 mg 100 g−1) and carotenoid (28.37 mg 100 g−1) contents, whilst buckwheat microgreens showed the highest total phenolic content (268.99 mg GAE 100 g−1) and DPPH• scavenging activity (90.83 mM TEAC g−1). The lentil microgreens also presented high ascorbic acid content (128.70 mg 100 g−1) along with broccoli, Chinese kale, purple radish, and red cabbage microgreens (79.11, 81.33, 82.58, and 89.49 mg 100 g−1, respectively). Anthocyanin content was only detected in purple radish (0.148 mg CGE 100 g−1) and red cabbage (0.246 mg CGE 100 g−1). The results provide basic information and highlight the benefits of utilizing genetic biodiversity to obtain microgreens with the desired nutrients and antioxidants.

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Okra pods, commonly eaten at an immature stage, undergo quick postharvest deterioration due to high respiration, water loss, wilting, toughening and decay. As okra is a tropical crop, its pods are susceptible to chilling injury (CI) at low storage temperatures. The effects of low temperature storage on the physiobiochemical properties of okra pods were determined. Chilling injury symptoms were found only in pods stored at 4°C and were more apparent after transfer to 25°C. In seeds, the CI index was positively correlated with seed browning, H 2 O 2 , malondialdehyde (MDA) content, and catalase (CAT) activity. Chilling-injured seeds had lower total phenolic content (TPC), antioxidant activity (DPPH scavenging activity and FRAP assay), peroxidase (POD), and superoxide dismutase (SOD) activities than non-injured seeds. Additionally, the seed browning index was related to high polyphenol oxidase (PPO) activity. In the pericarp, the CI index was also positively correlated with the H 2 O 2 and MDA contents. The POD and SOD activities in chilling-injured pericarp were significantly lower than in non-injured pericarp. Chilling injury resulted in an initial increase in DPPH scavenging and CAT activities which later decreased as CI became severe. These results indicate that CI in okra is due to accumulation of H 2 O 2 , and MDA, as well as its weak antioxidant defense mechanism. This resulted in development of CI symptoms, including seed browning.

Microbial contamination commonly occurs in microgreens due to contaminated seeds. This study investigated the decontamination effects of water wash (control), 5% hydrogen peroxide (H2O2), UV-C (36 watts), advanced oxidation process (AOP; H2O2 + UV-C), and improved AOP by combination with microbubbles (MBs; H2O2 + MBs and H2O2 + UV-C + MBs) on microbial loads, seeds’ viability, and physio-biochemical properties of microgreens from corresponding roselle seeds. Results showed that H2O2 and AOP, with and without MBs, significantly reduced total aerobic bacteria, coliforms, Escherichia coli (E. coli), and molds and yeast log count in seeds as compared to the control. Improved AOP treatment of H2O2 + UV-C + MBs significantly augmented antimicrobial activity against total bacteria and E. coli (not detected,) as compared to control and other treatments due to the formation of the highest hydroxy radicals (5.25 × 10−13 M). Additionally, H2O2 and combined treatments promoted seed germination, improved microbiological quality, total phenolic, flavonoids, and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) activity of the grown microgreens. Ascorbic acid content was induced only in microgreens developed from H2O2-treated seeds. Single UV-C treatment was ineffective to inactivate the detected microorganism population in seeds. These findings demonstrated that improved AOP treatment (H2O2 + UV-C + MBs) could potentially be used as a new disinfection technology for seed treatment in microgreens production.

Bean sprouts or "tauge" is a popular vegetable among the Malaysians. Sprouts are rich in nutrients, easily digested, but are perishable and have a short life cycle. Relatively, standard sprouts have long, thin hypocotyls and long roots. Some farmers use plant growth regulators, such as the 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP), to increase the hypocotyl thickness and inhibit bean sprout growth. Calcium makes the sprouts crispy, healthy and fresh. Thus, the objective of this study was to determine the efficiency of 2,4-D and BAP in influencing the growth of bean sprouts. Vigna mungo (black gram) seeds were used in this study. The bean seeds were treated with 2,4-D and BAP at 5, 10, 15 and 20 mg L-1, and each with the addition of 100 mg L-1 calcium. The beans sprouts were analyzed for soluble solids concentration (SSC), pH, titratable acidity and vitamin C. Physical characteristics, such as hypocotyl length, diameter and weight and root length, were determined. The experimental design was a randomized complete block design with a factorial arrangement of treatments. The results showed that seeds treated with 2,4-D and BAP produced significantly shorter sprout hypocotyl and roots length, thicker hypocotyls diameter and higher hypocotyls weight than sprouts from control (water treatment). Also, treated seeds produced sprouts with higher pH, vitamin C, SSC and titratable acidity compared to control. In conclusion, 2,4-D and BAP, produced desirable commercial characteristics of the bean sprouts.