Role of gamma-irradiated sodium alginate on growth, physiological and active components of iceberg lettuce (Lactuca sativa) plant.

BACKGROUND: One of the most widely recognized biostimulators of plant development; is oligoalginate, which regulates the biological processes of plants and was used in horticultural fields as a plant growth regulator. The plan of the current research was to study, however, the foliar application of un-irradiated and irradiated Na-alginate (UISA and ISA) to improve the growth, physiological activity, and other active components of the Egyptian iceberg lettuce plant. Degraded Na-alginate is equipped with exposure of sodium alginate in its solid state to gamma-rays at different dose levels (0.0, 25, 50, 75, and 100 kGy). The characterization of the oligo-alginates achieved by γ-radiation deprivation at different dose levels was performed by FTIR, XRD, TGA, SEM, and TEM. Different concentrations of irradiated sodium alginate at dose levels of 100 kGy (200, 400, 600, and 800 ppm, as well as deionized water used as a control) were sprayed with a hand sprayer every week after transplanting the iceberg lettuce seedlings in the field until the harvest stage. Morphological traits were evaluated, as well as pigments, ascorbic acid, phenols, flavonoids, soluble proteins, and antioxidant activity. RESULTS: Irradiated Na-alginate resulted in the depolymerization of Na-alginate into small molecular-weight oligosaccharides, and the best dose to use was 100 kGy. Certain chemical modifications in the general structure were observed by FTIR analysis. Two absorbed bands at 3329 cm-1 and 1599 cm-1, were recognized that are assigned to O-H and C-O stretching, respectively, and peaks achieved at 1411 cm-1 represent the COO-stretching group connected to the sodium ion. The peak obtained at 1028 cm-1 was owing to the stretching vibration of C-O. The results of TGA provided that the minimum weight reminder was in the ISA at 100 kGy (28.12%) compared to the UISA (43.39%). The images of TEM pointed out that the Na-alginate was globular in shape, with the particle distribution between 12.8 and 21.7 nm in ISA at 100 kGy. Irradiated sodium alginate caused a noteworthy enhancement in the vegetative growth traits (leaf area, stem length, head weight, and leaf number). By spraying 400 ppm, ISA showed a maximum increase in total pigments (2.209 mg/g FW), ascorbic acid (3.13 mg/g fresh weight), phenols (1.399 mg/g FW), flavonoids (0.775 mg/g FW), and antioxidant activities (82.14. %). Also, there were correlation coefficients (R values) between leaf area, stem length, head weight, and leaf number values with total pigment content, antioxidant activity, total soluble proteins, and ascorbic acid. CONCLUSIONS: The outcomes of the recent investigation demonstrated that the application of spraying irradiated Na-alginate (100 kGy) resulted in an improvement of the considered characters.

Changes in morphological traits, anatomical and molecular alterations caused by gamma-rays and zinc oxide nanoparticles in spinach (Spinacia oleracea L.) plant.

Spinach seeds were irradiated with gamma-rays after that soaked in zinc oxide nanoparticles (ZnO-NPs) at 0.0, 50, 100 and 200 ppm for twenty-four hours at room temperature. Vegetative plant growth, photosynthetic pigments, and proline contents were investigated. Also, anatomical studies and the polymorphism by the SCoT technique were conducted. The present results revealed that the germination percentage was at the maximum values for the treatment of 100 ppm ZnO-NPs (92%), followed by 100 ppm ZnO-NPs + 60 Gy (90%). The application of ZnO-NPs resulted in an enhancement in the plant length. The maximum of chlorophylls and carotenoids content was recorded in the treatment, 100 ppm ZnO-NPs + 60 Gy. Meanwhile, the irradiation dose level (60 Gy) with all ZnO-NPs treatments increased proline content and reached its maximum increase to 1.069 mg/g FW for the treatment 60 Gy combined with 200 ppm ZnO-NPs. Also, the anatomical studies declared that there were variations between the treatments; un-irradiated and irradiated combined with ZnO-NPs plants which reveal that the leave epidermal tissue increased with 200 ppm ZnO-NPs in both the upper and lower epidermis. While irradiated plants with 60 Gy combined with 100 ppm ZnO-NPs gave more thickness of upper epidermis. As well as SCoT molecular marker technique effectively induced molecular alterations between the treatments. Where, SCoT primers targeted many new and missing amplicons that are expected to be associated with the lowly and highly expressed genes with 18.2 and 81.8%, respectively. Also, showed that the soaking in ZnO-NPs was helped for reducing molecular alteration rate, both spontaneous and induced by gamma irradiation. This nominates ZnO-NPs as potential nano-protective agents that can reduce irradiation-induced genetic damage.

Physiological and biochemical markers of gamma irradiated white radish (Raphanus sativus).

PURPOSE: A field experiment was performed to investigate the impact of low-dose gamma rays on growth parameters and bioactive compounds of white radish. MATERIALS AND METHODS: White radish seeds were irradiated by gamma rays dose levels (10, 20, 40 and 80 Gy) beside control. Physiological and biochemical markers were done to follow the effect of gamma rays on white radish. RESULTS: The results revealed that gamma rays increased growth parameters with increasing irradiation to a dose of 40 Gy. The maximum increments were found at 14.64 (cm), 48.30 (cm), 20.84 (cm) and 5.51 (cm) for leaves number, leaves length, roots length and roots diameter, respectively, with a dose of 40 Gy. By increasing the irradiation dose to 80 Gy, the results showed reduction in all parameters studied. Ascorbic acid gave the maximum increase with the dose of 40 Gy, while phenols, flavonoids, antioxidant activity, peroxidase, and polyphenol oxidase showed the highest increase with the dose 80 of Gy in radish leaves. Similar trend was observed for the radish roots. Furthermore, the protein and isoenzyme profiles of peroxidase and polyphenol oxidase changed and induced alteration by different irradiation dose levels. CONCLUSION: Gamma rays can be a useful tool for increasing the growth and biochemical content of white radish plants and perhaps other food crops.

Phytochemical constitutes and biological activities of essential oil extracted from irradiated caraway seeds (Carum carvi L.).

PURPOSE: Essential oils (EOs) obtained from spices, herbs, and medicinal plants are well known in traditional medicine and are an area of interest due to their various biological activities. Therefore, the present study investigates the chemical composition, phytochemical properties, as well as the biological activity of EOs, recovered from un-irradiated and irradiated (2.5, 5, and 10 kGy) caraway seeds. MATERIALS AND METHODS: Carum carvi L. seeds were irradiated with gamma irradiation at dose levels 2.5, 5, and 10 kGy, then EOs were recovered from all the samples. The chemical composition, phenols, and flavonoids content were evaluated. As well, antimicrobial and antitumor activities against the two cell lines [colorectal adenocarcinoma (Caco-2) and liver cancer (HepG-2)] were investigated. RESULTS: The results indicated the percentage of oil increased by radiation, especially a dose of 10 kGy, which gave the highest percentage (3.50%) compared to the control. Also, the Gas Chromatography/Mass Spectrometry (GC-MS) analysis revealed the presence of 26 compounds in the essential oil extracts. The main constituent of caraway seeds EOs was Carvone followed by Limonene. According to the results, there was an increase in the content of phenols and flavonoids by using gamma rays compared with control, the maximum increase was observed at dose level 10 kGy (13.70 and 7.38 mg/g oil, respectively) followed by 5 kGy (11.20 and 5.86 mg/g oil, respectively). The antioxidant properties of the caraway essential oils were increased by increasing the irradiation dose level (2.5-10 kGy) analyzed by DPPH radical and metal chelating activity. Caraway essential oils have an antimicrobial action against Gram-positive and Gram-negative bacteria as well as fungi. The antimicrobial activity was increased as the irradiation dose was raised and the10 kGy dose was more effective in suppressing the growth of bacteria and fungi. Additionally, the caraway essential oils have anticancer activity against the two cell lines studied; colorectal adenocarcinoma (Caco-2) and liver cancer cell line (HepG-2) as reduced the cell viability and density. CONCLUSION: The 10 kGy dose was more effective for oil yield, phenols, flavonoids, and antioxidant activity as well as antibacterial and antifungal activities. Furthermore, the caraway essential oils indicated anticancer activity against the two cell lines studied; colorectal adenocarcinoma (Caco-2) and liver cancer cell line (HepG-2) as reduced the cell viability and density. So caraway could be considered an important herb with multiple therapeutic uses.

Characterizing the Bioactive Ingredients in Sesame Oil Affected by Multiple Roasting Methods.

Roasting is an important step in sesame (Sesamum indicum L.) processing. The current research was undertaken to evaluate the oil content, fatty acid (FA) profiles, and physicochemical characteristics of oil recovered from sesame roasted by different methods (cooker oven, stovetop pan, microwave, and electric frying pan). Roasting sesame seeds changed their oil content according to the roasting method used, with content ranging from 49.83% in control to 59.85% in the roasting by microwave. In oils recovered from raw or roasted seeds, seven fatty acids were obtained through gas chromatography. Changes in the fatty acid profiles occurred in all the treatments, and the total unsaturated fatty acid content was higher than that of saturated fatty acids. The obtained peroxide number of sesame oils was inside the rate of 3.90 meq/kg oil for microwave treatment versus 1.59 meq/kg oil for unroasted. The highest acid value was with the stovetop pan treatment at 3.78 mg/g, followed by the microwave treatment at 3.24 mg/g; the oven treatment gave the lowest value at 1.66 mg/g. The lowest iodine value was observed with the electric frying pan treatment (102.30/100 g oil), and phytosterols were most abundant with the microwave treatment. Moreover, the phenolic and flavonoid contents and antioxidant activity were the highest with the microwave roasting. The FTIR spectrum illustrated slight differences in peaks intensity (1738, 1454, 1151, 710 cm-1) between the roasting methods used. The finding of the current investigation of roasting methods was that the fatty acid profiles were across methods. As is clear from the obtained results, the microwave roasting treatment is the favoured roasting method for the healthiest sesame seed oil contents. Sesame seeds are considered a significant and abundant resource with numerous beneficial nutrients that positively affect human health.