Green Lettuce Research Articles

Changes in Soil Characteristics, Microbial Metabolic Pathways, TCA Cycle Metabolites and Crop Productivity following Frequent Application of Municipal Solid Waste Compost.

The benefit sof municipal solid waste (MSW) compost on soil health and plant productivity are well known, but not its long-term effect on soil microbial and plant metabolic pathways. A 5-year study with annual (AN), biennial (BI) and no (C, control) MSW compost application were carried out to determine the effect on soil properties, microbiome function, and plantgrowth and TCA cycle metabolites profile of green beans (Phaseolus vulgaris), lettuce (Latuca sativa) and beets (Beta vulgaris). MSW compost increased soil nutrients and organic matter leading to a significant (p < 0.05) increase in AN-soil water-holding capacity followed by BI-soil compared to C-soil. Estimated nitrogen release in the AN-soil was ca. 23% and 146% more than in BI-soil and C-soil, respectively. Approximately 44% of bacterial community due to compost. Deltaproteobacteria, Bacteroidetes Bacteroidia, and Chloroflexi Anaerolineae were overrepresented in compost amended soils compared to C-soil. A strong positive association existed between AN-soil and 18 microbial metabolic pathways out of 205. Crop yield in AN-soil were increased by 6-20% compared to the BI-soil, and by 35-717% compared to the C-soil. Plant tricarboxylic acid cycle metabolites were highly (p < 0.001) influenced by compost. Overall, microbiome function and TCA cycle metabolites and crop yield were increased in the AN-soil followed by the BI-soil and markedly less in C-soil. Therefore, MSW compost is a possible solution to increase soil health and plants production in the medium to long term. Future study must investigate rhizosphere metabolic activities.

Secondary Metabolite Profile and Pharmacological Opportunities of Lettuce Plants following Selenium and Sulfur Enhancement.

Selenium (Se) is an essential trace nutrient for humans and animals owing to its role in redox regulation, thyroid hormone control factors, immunity, inflammatory reactions, brain activities, and carbohydrate regulation. It is also important to support muscle development, as well as for reproductive and cardiovascular well-being. Furthermore, sulfur is known to be a healing element, due to the remarkable function of specialized and secondary S-containing compounds. The scope of the current study was to determine the impact of Se and S enrichment on the secondary metabolite accumulation and antibacterial and NO inhibition activities in green and red leaf lettuce (V1 and V2, respectively). The plants were grown in a hydroponic system supplied with different S concentrations (S0: 0, S1: 1 mM and S2: 1.5 mM K2SO4) via the nutrient solution and foliar-applied varying levels of Se (0, 0.2 and 2.6 µM). Electrospray ionization-quadrupole time-of-flight mass spectrometry (ESI-QTOF/MS) combined with ultra-performance liquid chromatography (UPLC) was used to identify the secondary metabolites in green and red lettuce. The results indicated that extracts of the biofortified lettuce were not cytotoxic to Vero kidney cells at the highest concentration tested of 1 mg/mL. The ESI/MS of the tentatively identified metabolites showed that the response values of 5-O-caffeoylquinic acid, cyanidin 3-O-galactoside, quercetin 3-O-(6''-acetyl-glucoside) and quercetin 3-O-malonylglucoside were induced synergistically under higher Se and S levels in red lettuce plants. The acetone extract of red lettuce had antibacterial activity against Pseudomonas aeruginosa, with a minimum inhibitory concentration (MIC) of 0.156 and 0.625 μg/mL under S2/Se1 and S2/Se2 treatments, respectively. As with antibacterial activity, the acetone extract of green (V1) lettuce treated with adequate (S1) and higher S (S2) under Se-limiting conditions showed the ability to inhibit nitric oxide (NO) release from macrophages. NO production by macrophages was inhibited by 50% at respective concentrations of 106.1 ± 2.4 and 101.0 ± 0.6 μg/mL with no toxic effect on the cells, in response to S1 and S2, respectively, under Se-deficient conditions (Se0). Furthermore, the red cultivar (V2) exhibited the same effect as the green cultivar (V1) regarding NO inhibition, with IC50 = 113.0 ± 4.2 μg/mL, in response to S1/Se2 treatments. Collectively, the promising NO inhibitory effect and antibacterial activity of red lettuce under the above-mentioned conditions might be attributed to the production of flavonoid glycosides and phenylpropanoic acid esters under the same condition. To the best of our knowledge, this is the first report to show the novel approach of the NO inhibitory effect of Se and S enrichment in food crops, as an indicator for the potential of Se and S as natural anti-inflammatory agents.

Mineral-Soil-Plant-Nutrient Synergisms of Enhanced Weathering for Agriculture: Short-Term Investigations Using Fast-Weathering Wollastonite Skarn.

Enhanced weathering is a proposed carbon dioxide removal (CDR) strategy to accelerate natural carbon sequestration in soils via the amendment of silicate rocks to agricultural soils. Among the suitable silicates (such as basalt and olivine), the fast-weathering mineral wollastonite (CaSiO3) stands out. Not only does the use of wollastonite lead to rapid pedogenic carbonate formation in soils, it can be readily detected for verification of carbon sequestration, but its weathering within weeks to months influences soil chemistry and plant growth within the same crop cycle of its application. This enables a variety of short-term experimental agronomic studies to be conducted to demonstrate in an accelerated manner what could take years to be observed with more abundant but slower weathering silicates. This study presents the results of three studies that were conducted to investigate three distinct aspects of wollastonite skarn weathering in soils in the context of both agricultural and horticultural plants. The first study investigated the effect of a wide range of wollastonite skarn dosages in soil (1.5–10 wt.%) on the growth of green beans. The second study provides insights on the role of silicon (Si) release during silicate weathering on plant growth (soybeans and lettuce). The third study investigated the effect of wollastonite skarn on the growth of spring rye when added to soil alongside a nitrogen-based coated fertilizer. The results of these three studies provide further evidence that amending soil with crushed silicate rocks leads to climate-smart farming, resulting in inorganic carbon sequestration, as well as better plant growth in agricultural (soybean and spring rye) and horticultural (green bean and lettuce) crops. They also demonstrate the value of working with wollastonite skarn as a fast-weathering silicate rock to accelerate our understanding of the mineral–soil–plant–nutrient synergism of enhanced weathering.

Phytochemical Analysis and Antibacterial Potential of Tabon-tabon (Atuna racemosa Raf) Fruit Extract against E. Coli BIOTECH 1634

This study aimed to examine the phytochemical levels of crude “tabon-tabon” (Atuna racemosa Raf.) fruit extracts subjected to air-drying, oven-drying, and freeze-drying. It also sought to validate the claims of previous literature on the fruit’s antimicrobial properties by using its aqueous extracts as an antibacterial wash for green ice leaf lettuce. Phytochemical analysis revealed significantly higher (p < 0.05) levels of alkaloids and tannins compared to coumarins, saponins, and terpenoids. The highest alkaloid content (16.25 ± 1%) was obtained using oven- drying, whereas the highest tannin content was obtained using freeze-drying (14.14 ± 1.13%). In vivo antibacterial assay against Escherichia coli was performed to test the aqueous extracts alongside 200 ppm chlorine solution and water for comparison. Artificially-inoculated lettuce samples were individually soaked in 15-mL solution at 2- and 5-min contact times. Bacterial load was determined at a 2-d interval for a period of 8 d. Results of the microbiological analysis showed no significant interaction in the soaking time used. However, the treatments were independently found to have significant effects on Days 0, 4, and 6. The highest antibacterial effect in green ice lettuce was exhibited up to Day 6.

Karakteristik Morfologi Tanaman Selada Menggunakan Pengolahan Citra Digital

The aim of this study is to find out characteristics of Green Rapid lettuce with digital image processing using morphological technique on image and first order statistical feature extraction. In digital image processing, the original images were processed to be RGB image and then processed again to be grayscale one. The grayscale images were processed to be biner image so that the image can be changed into biner form (0 and 1). In morphological process, this study used edge detection, dilation, and erosion. The final stage of morphological process used feature extraction process to find out image morphological characteristics which can be described mathematically. The result of extraction showed its samples within range or average area about 9.593.622.205.915.820 pixels, perimeter about 8.427.724.410.694.360 pixels, length about 829.877.174.308.893 pixels, and width about 1.654.002.663.010.820 pixels

In-door germination and seedling growth of green and red lettuce under LED-light spectrum and subsequent effect on baby leaf lettuce

The spectrum and intensity of light play a significant role in the primary and secondary metabolism of plants. Low intensity can make the photosynthetic process less efficient, while inadequate spectrum can impair plant growth and quality. This study investigates the effect of different LED light spectra at low intensity on germination and growth of lettuce (Lactuca sativa L.) seedlings under a temperature-controlled chamber and the subsequent impact on mature plants grown in a greenhouse under natural light. The purpose was to reach a commercial plant seedling using a low amount of energy to achieve the yield potential in a shorter period. The experiment was carried out in three trials. In trial 1, the effect of different LED light wavelengths [100% blue (B); 100% red (R); mixed light 1 (52% blue, 27% green and 21% red) (BGR1), and mixed light 2 (29% blue, 53% green and 17% red and 1% far red) (BGR2)] at low intensity (55 μmol m–2 s–1 and 12 h light photoperiod) and darkness (control) on germination of two lettuce cultivars [‘Levistro’ (green) and ‘Carmolí’ (red)] was evaluated in a controlled temperature chamber (20±1.2°C). In trial 2, the effect of the same light conditions of the first experiment on agronomic characteristics and pigment contents of lettuce seedlings compared to the natural light (control: 451±66 μmol m–2 s–1) were evaluated. In trial 3, the seedlings developed under different LED light wavelengths were transplanted to evaluate the subsequent effect on the growth of baby lettuce cultivated hydroponically in the greenhouse under natural light. The results of this study show that red wavelength reduced germination percentage, while lights with a higher blue component (B and BGR1) accelerated germination and increased the number of germinated seeds in ‘Levistro’. Red also delayed germination and decreased the number of germinated seeds in ‘Carmolí’ compared to darkness. Seedlings of ‘Levistro’ had a higher fresh weight (FW) than ‘Carmolí’. In addition, FW increased under BGR2 and R, which coincided with the highest number of leaves and leaf length. Nevertheless, fresh weight was higher under BGR2 and B after transplanting, coinciding with the highest number of leaves. A higher blue component of the light (B and BGR1) increased the dry matter percentage (DMP) of seedlings, but there was no significant difference after transplanting. Chlorophyll (CHL) a and b content increased under BGR2; however, the highest CHL a/b ratio was observed under BGR1 in ‘Levistro’ and B in ‘Carmolí’, but it was higher after transplanting when seedlings were grown under B. The anthocyanin (ANT) content of ‘Carmolí’ seedlings was promoted by a higher blue component of the light (B and BGR1) but significantly increased under natural light (control) at the highest intensity. This work shows that varying the spectrum at low intensity can positively modify the growth and biochemical characteristics of lettuce seedlings, although the effect depends on the cultivar. This modification improves the performance of plants during greenhouse growth after transplanting, especially seedlings grown under B and BGR2. Highlights - Blue light enhanced germination and increased the number of germinated seeds of green lettuce. - High blue component lights improved the morphology, dry matter percentage, and chlorophyll a/b ratio of lettuce seedlings. - Blue and full-spectrum lights applied to lettuce seedlings affect fresh weight after transplanting. - The anthocyanin content of seedlings was stimulated by blue light at 55 μmol m–2 s–1, but even more so by PAR of natural light at 451 μmol m–2 s–1.

Effect of LED lighting on phytochemical content of lettuce plants (green coral and red coral) grown in plant factory condition

Light is one of the most important environmental factors that affect plant growth. Lightemitting diodes (LEDs) are alternative lighting that has been shown to have the potential for plant growth and development under controlled conditions in plant factories. Plant factory production technology can increase the productivity and nutritional content of the plant. The phytochemical content of lettuce plants (Green Coral and Red Coral) grown under plant factory conditions with different spectrum LED lights (combination of red and blue LED and red, blue and green LED) were studied. The lettuce was harvested from day 20 until 35 after transplanting with an interval of five days. The result showed that the combination of red, blue and green LED lights is positive in terms of phytochemical content in both lettuce plants. Harvesting at days 30 to 35 after transplanting was effective in presenting a higher value in total chlorophyll, percentage of DPPH inhibition and reduction of total phenolic content in green Coral lettuce compared to early harvesting as it showed a highly significant difference. Besides, the chlorogenic acid content in green and red Coral presented significantly increased when harvesting was done on day 35. The combination of red, blue and green LED greatly affected chlorogenic acid content in both lettuces’ plants. Therefore, the result of the combination of LED and harvesting day might provide new information to improve the nutritional quality of lettuce plants after harvesting.

Response of Cyanic and Acyanic Lettuce Cultivars to an Increased Proportion of Blue Light.

Simple SummaryIndoor crop cultivation systems such as vertical farms or plant factories necessitate artificial lighting. The composition of light quality (i.e., spectral composition) within these systems plays a key role in crop growth and development. Conflicting results on the effects of the light spectrum reported for different plant species and cultivars confirm the specificity of light requirements and the dependency on interacting factors. In this paper, we have therefore investigated how a certain light quality (light with a high share of blue) affects photosynthetic and morphological parameters in two contrasting lettuce cultivars (red and green leaves) with a similar leaf shape and phenotype. The results obtained suggest the occurrence of distinctive morpho-physiological adaptive strategies in green and red pigmented lettuce cultivars to adapt to the higher proportion of blue light environment.Indoor crop cultivation systems such as vertical farms or plant factories necessitate artificial lighting. Light spectral quality can affect plant growth and metabolism and, consequently, the amount of biomass produced and the value of the produce. Conflicting results on the effects of the light spectrum in different plant species and cultivars make it critical to implement a singular lighting solution. In this study we investigated the response of cyanic and acyanic lettuce cultivars to an increased proportion of blue light. For that, we selected a green and a red leaf lettuce cultivar (i.e., ‘Aquino’, CVg, and ‘Barlach’, CVr, respectively). The response of both cultivars to long-term blue-enriched light application compared to a white spectrum was analyzed. Plants were grown for 30 days in a growth chamber with optimal environmental conditions (temperature: 20 °C, relative humidity: 60%, ambient CO2, photon flux density (PFD) of 260 µmol m−2 s−1 over an 18 h photoperiod). At 15 days after sowing (DAS), white spectrum LEDs (WW) were compared to blue-enriched light (WB; λPeak = 423 nm) maintaining the same PFD of 260 µmol m−2 s−1. At 30 DAS, both lettuce cultivars adapted to the blue light variant, though the adaptive response was specific to the variety. The rosette weight, light use efficiency, and maximum operating efficiency of PSII photochemistry in the light, Fv/Fm’, were comparable between the two light treatments. A significant light quality effect was detected on stomatal density and conductance (20% and 17% increase under WB, respectively, in CVg) and on the modified anthocyanin reflectance index (mARI) (40% increase under WB, in CVr). Net photosynthesis response was generally stronger in CVg compared to CVr; e.g., net photosynthetic rate, Pn, at 1000 µmol m−2 s−1 PPFD increased from WW to WB by 23% in CVg, compared to 18% in CVr. The results obtained suggest the occurrence of distinct physiological adaptive strategies in green and red pigmented lettuce cultivars to adapt to the higher proportion of blue light environment.

Phytochemicals, Nutrition, Metabolism, Bioavailability, and Health Benefits in Lettuce-A Comprehensive Review.

Lettuce is one of the most famous leafy vegetables worldwide with lots of applications from food to other specific uses. There are different types in the lettuce group for consumers to choose from. Additionally, lettuce is an excellent source of bioactive compounds such as polyphenols, carotenoids, and chlorophyll with related health benefits. At the same time, nutrient composition and antioxidant compounds are different between lettuce varieties, especially for green and red lettuce types. The benefit of lettuce consumption depends on its composition, particularly antioxidants, which can function as nutrients. The health benefits rely on their biochemical effect when reaching the bloodstream. Some components can be released from the food matrix and altered in the digestive system. Indeed, the bioaccessibility of lettuce is measuring the quantity of these compounds released from the food matrix during digestion, which is important for health-promoting features. Extraction of bioactive compounds is one of the new trends observed in lettuce and is necessarily used for several application fields. Therefore, this review aims to demonstrate the nutritional value of lettuce and its pharmacological properties. Due to their bioaccessibility and bioavailability, the consumer will be able to comprehensively understand choosing a healthier lettuce diet. The common utilization pattern of lettuce extracted nutrients will also be summarized for further direction.

Plant-Derived Biostimulants Differentially Modulate Primary and Secondary Metabolites and Improve the Yield Potential of Red and Green Lettuce Cultivars

The use of biostimulants in modern agriculture has rapidly expanded in recent years, owing to their beneficial effects on crop yield and product quality, which have come under the scope of intensive research. Accordingly, in the present study we appraised the efficacy of two plant-derived biostimulants, the legume-derived protein hydrolysates Trainer® (PH), and the tropical plant extract Auxym® (TPE) on two lettuce cultivars (green and red salanova®) in terms of morpho-physiological and biochemical traits (primary and secondary metabolites). The two cultivars differed in their acquisition capacity for nitrate and other beneficial ions, their photosynthetic and transpiration rates, and their ability to synthetize and accumulate organic acids and protective metabolites. The biostimulant effect was significant for almost all the parameters examined but it was subjected to significant cultivar × biostimulant interactions, denoting a cultivar-dependent response to biostimulant type. Notwithstanding this interaction, biostimulant application could potentially improve the yield and quality of lettuce by stimulating plant physiological processes, as indicated by the SPAD index (leaf chlorophyll index), ACO2 (assimilation rate), E (transpiration), and WUEi (intrinsic water use efficiency), and by increasing concurrently the plant mineral content (total N, K, Ca, Mg) and the biosynthesis of organic acids (malate, citrate), phenols (caffeic acid, coumaroyl quinic acid isomer 1, dicaffeoylquinic acid isomer 1), and flavonoids (quercetin-3-O-glucuronide, quercetin-3-O-glucoside). Biostimulant action may facilitate the bio-enhancement of certain lettuce cultivars that are otherwise limited by their genetic potential, for the accumulation of specific compounds beneficial to human health.

Enhancement of Lettuce Growth by PAW Spray Gliding Arc Plasma Generator

The effect of non-thermal air plasma on green oak lettuce farming has been proposed. A gliding arc plasma generator (GAPG) was designed for plasma-activated water (PAW) spray generation. A PAW spray was generated at 8, 10, and 12 kV by a custom-made ac high voltage power supply. Four hydroponic green oak lettuce trays were treated by PAW spray at different conditions for 10 min, three times a day for nine days. The experimental results showed that all the plasma-treated green oak lettuce sprouts had a greater growth rate than the control group. The best condition was found in the PAW spray generated at 8 kV source voltage, which led to the longest average height and width of sprouts of 10.88 ± 0.33 cm and 10.09 ± 0.08 cm, respectively. Moreover, its average dried weight was also significantly greater than that of the control group by 1.69 times. It was found that the concentration of total Kjeldahl nitrogen (TKN), mainly ammonium, was enhanced in every PAW spray condition. However, the highest TKN concentration was found in the 8 kV PAW spray, which was 3.67 times higher than that of the control group. The amount of nitrite (NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−</sup> ) and nitrate (NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−</sup> ) in PAW spray was also enhanced but in the opposite trend to TKN concentration. Moreover, the electrical conductivity (EC) and pH levels could be improved by air plasma. It could be confirmed that the plasma treatment could be effectively applied to green oak lettuce farming, and the PAW spray generated by the GAPG could enhance the amount of nitrogenous fertilizer in treated water, which is essential for plant growth stimulation.

Risk assessment of carbofuran residues in fruits and vegetables at the Chinese market: A 7-year survey

The United Nations designated 2021 as the International Year of Fruits and Vegetables (IYFV), with the goal of educating populations regarding the role of such produce in nutrition, food safety, and overall health. Carbofuran is a highly toxic insecticide and nematocide, and its use to treat fruit trees, vegetables, tea, and medicinal herbs is thus prohibited. However, carbofuran residues are still detectable via LC-Q-TOF/MS in fruit and vegetable samples collected from 138 sites in 31 regions. In the present study, carbofuran levels were sampled at 1388 sampling sites in 31 regions (provinces, autonomous regions, and municipalities) not including Hong Kong, Macao, or Taiwan. In total, over 36,000 samples (including 12,547 samples of 41 kinds of fruits and 23,785 samples of 83 kinds of vegetables) were randomly collected from supermarkets and farmer’s markets. These data were used to conduct a risk assessment pertaining to dietary carbofuran exposure through the consumption of fruits and vegetables. In total, carbofuran residues were detectable in 2.0% of fruits and 2.3% of vegetables. Risk assessments indicated that the intake of fruits and vegetables harboring carbofuran residues did not pose a chronic health risk. However, peaches, grapes, sweet peppers, celery, Chinese chives, leaf lettuce, spinach, small rape, mustard greens, cucumbers, watermelons, Chinese wolfberry leaves, wax gourds, snap beans, bitter melons, green Chinese vegetables, lettuce, shallot, cowpeas, eggplants, tomatoes, tangerines, summer squash, oranges, lemons, Chinese cabbage, peppers, and strawberries were associated with an unacceptable acute risk to both children and adults. Moreover, crown daisies, nectarines, citrus fruits, pitayas, melons, kale, cabbages, milk Chinese cabbage, carrots, and melons were associated with an unacceptable acute risk to children. Substantial acute risk to children and adults was observed for fruits and vegetables from surveyed regions other than Inner Mongolia, Yunnan, Liaoning, Fujian, Xinjiang, and Hubei. Together, these data provide a foundation for future research aimed at the management of carbofuran residues in fruits and vegetables in an effort to better protect consumer health.

The effect of lime oil emulsion on seed germination, antimicrobial and antioxidant properties of hydroponic baby green oak lettuce for the assurance of safety from farm to fork

AbstractThis study aimed to investigate the effect of soaking lettuce seeds in a lime oil emulsion at 0 (control), 10, 20, 30, 40, and 50 μl/ml before growing them in a hydroponic plantation. After harvesting baby lettuce at Day 21, all lettuce was kept inside the refrigerator (4 ± 2°C) for the next 7 days. The microbiological quality and the antioxidant properties of lettuce were also investigated. The results revealed that while lime oil emulsion at 10 μl/ml had no effect on seed germination, it delayed the growth of black spot molds and reduced the incidence and severity of black spot fungal disease in baby lettuce by around 87.5%. The morphology of Alternaria sp. and Cercospora sp. shows ruptured conidia and shriveled and damaged mycelium, with a decrease in fungal infection in baby lettuce. In addition, α‐terpineol (~53%) was identified from treated baby lettuce after 21 days that was able to inhibit growth of molds. Regarding the microbial eating quality of baby lettuce, mesophiles (~3.0 log10 CFU/g), psychrophiles (~3.6 log10 CFU/g), total coliforms (~1.3 log10 CFU/g), total yeast and mold (~2.0 log10 CFU/g) and lactic acid bacteria (~3.7 log10 CFU/g) were significantly reduced in the treated lettuce. The antioxidant capacity in the treated lettuce was higher than the control and maintained stability without affecting its leafy green color and chlorophyll content. This finding is critical for horticulture, particularly in hydroponic vegetable farming. It can be applied in food safety from farm to fork.

Alterations of Content and Composition of Individual Sulfolipids, and Change of Fatty Acids Profile of Galactolipids in Lettuce Plants (Lactuca sativa L.) Grown under Sulfur Nutrition.

Alterations of chloroplast membrane lipids might serve as indicators of eco-physiologically induced and plant nutrition-induced changes during plant growth. The change in the degree of fatty acid saturation in the membranes is in particular a strategy of plants to adapt to abiotic stress conditions. Green multi-leaf lettuce plants (Lactuca sativa L.) were subjected to three different sulfur (S) levels. Sulfoquinovosyl diacylglycerol derivatives (SQDG) might be affected by S nutrition. Therefore, the present study was conducted to investigate the impact of S fertilization on the content and composition of individual SQDG. In addition to a change in the SQDG composition, a general change in the total lipid composition of the chloroplast membrane was observed. A significant increase in total SQDG content and doubling of the galactolipid content and significant alterations of individual SQDG were observed at elevated levels of S fertilization. High levels of S supply demonstrated a clear trend of increasing total chloroplast lipid content and concentrations of linolenic acid, in addition to a further decline in palmitic acid. The study opens perspectives on S supply and its crucial role in the build-up of photosynthetic apparatus. Moreover, it emphasizes the role of S-containing compounds, including sulfolipids, in modulating physiological adjustment mechanisms to improve tolerance ability to various abiotic stresses in plants and, consequently, plant food quality.

Assessment of the bioaccessibility of phenolics from Australian grown lettuces by in vitro simulated gastrointestinal digestion and colonic fermentation

Lettuce varieties are rich in phytochemicals with strong antioxidant properties, mainly due to the presence of many phenolic compounds. The health effects of these phenolic compounds are dependent on their bioaccessibility, bioavailability and bioactivities. This study aimed to evaluate the differences in the content and bioaccessibility of phenolic compounds in green lettuce (iceberg, baby cos, and green little gem) and red lettuce (red oak leaf, lollo rosso, and red little gem), their antioxidant properties and short chain fatty acids (SCFAs) production after in vitro gastrointestinal digestion and colonic fermentation. Lollo rosso showed the highest content of phenolic compounds (1.23 mg GAE/g) and flavonoids (0.36 mg QE/g), as well as the antioxidant capacities after gastrointestinal digestion. After colonic fermentation, only baby cos and red little gem showed significantly higher TPC (5.13 mg GAE/g) and TFC (1.95 mg GAE/g), respectively. Most phenolic compounds in lettuce were mostly bioaccessible after gastric and small intestinal digestion, except for the kaempferol which relied more on the colonic fermentation. However, high percentage of kaempferol still could be found in the colonic fermented residual, probably due to the presence of dietary fiber and the interactions with other components. All lettuce varieties achieved the peak production of SCFAs after 16 h, except iceberg which displayed the highest total SCFAs production just after 8 h fermentation. It could be inferred that the iceberg (green lettuce) could be more beneficial to gut health while lollo rosso (red lettuce) could contribute more antioxidant properties after consumption.

Handheld Multifunctional Fluorescence Imager for Non-invasive Plant Phenotyping.

Fluorescence imaging has shown great potential in non-invasive plant monitoring and analysis. However, current systems have several limitations, such as bulky size, high cost, contact measurement, and lack of multifunctionality, which may hinder its applications in a wide range of settings including indoor vertical farming. Herein, we developed a compact handheld fluorescence imager enabling multipurpose plant phenotyping, such as continuous photosynthetic activity monitoring and non-destructive anthocyanin quantification. The compact imager comprises of pulse-amplitude-modulated multi-color light emitting diodes (LEDs), optimized light illumination and collection, dedicated driver circuit board, miniaturized charge-coupled device camera, and associated image analytics. Experiments conducted in drought stressed lettuce proved that the novel imager could quantitatively evaluate the plant stress by the non-invasive measurement of photosynthetic activity efficiency. Moreover, a non-invasive and fast quantification of anthocyanins in green and red Batavia lettuce leaves had excellent correlation (>84%) with conventional destructive biochemical analysis. Preliminary experimental results emphasize the high throughput monitoring capability and multifunctionality of our novel handheld fluorescence imager, indicating its tremendous potential in modern agriculture.

Paenibacillus polymyxa reduces leaf spot disease caused by Cersocpora sp. and has potential to promote growth in green oak lettuce (Lactuca sativa var. crispa) in the commercial hydroponic farm

ISHS IX International Scientific and Practical Conference on Biotechnology as an Instrument for Plant Biodiversity Conservation (physiological, biochemical, embryological, genetic and legal aspects) Paenibacillus polymyxa reduces leaf spot disease caused by Cersocpora sp. and has potential to promote growth in green oak lettuce (Lactuca sativa var. crispa) in the commercial hydroponic farm

CARBENDAZIM RESIDUES QUANTIFICATION IN GREEN LETTUCE BY ENZYME-LINKED IMMUNOSORBENT ASSAY

Carbendazim is a fungicide that is not approved for use in the European Union, but is used in some other countries to preserve agricultural crops. Enzyme-linked immunosorbent assay (ELISA) become a viable alternative to traditional instrumental methods in pesticides analysis, for screening purpose. Carbendazim residues were determined in two green lettuce cultivars, from the experimental lots, harvested at different times after the treatment with 0.1 % carbendazim solution, by an ELISA carbendazim commercial kit and the values were compared with those obtained by high performance liquid chromatography (HPLC). The results of ELISA and HPLC analysis of carbendazim residues in the two green lettuce cultivars were well correlated (Pearson correlation coefficient r=0.8925). Carbendazim residues in green lettuce/vegetables can be determined with high reliability by commercial ELISAs with results well correlated with those obtained by HPLC, with an additional sample preparation step involving solid phase extraction, in order to reduce matrix effects; the assay can be used for carbendazim screening of many vegetable/fruit samples in shorter time and with inexpensive/cheaper equipment.

Penentuan Kandungan Antioksidan Total pada Infusa Selada Hijau (Lactuca sativa L.) Hidroponik dan Konvensional secara Spektrofotometri dengan Modified Phenantroline Method (MPM)

Green lettuce is a vegetable that is widely consumed in Indonesia. These vegetables come from conventional and hydroponic farming. This study aims to compare the antioxidant content of these two types of vegetables. This vegetable is extracted by the infundation method. The extract obtained was determined for its antioxidant content by the MPM method. This method was validated by using parameter LoD, LoQ, linearity, precision and accuracy. The results showed that this method was valid for determining the total antioxidant content in conventional and hydroponic green lettuce samples. The total antioxidant content in conventional and hydroponic green lettuce samples was 2.68 ± 0.65 mg aa/g FW and 1.67 ± 0.40 mg AA/g FW, respectively. T test stated that the antioxidant content of the two samples was significantly different.

The in vitro anti-platelet activities of plant extracts from the Asteraceae family

Foods prepared from the Asteraceae family are known to exert in vitro antioxidant activity. For example, roots and fruit extracts from dandelion were found to possess antioxidant and anti-platelet potential in two in vitro models (washed blood platelets and whole blood). However, little is known of other extracts from the Asteraceae, such as chicory leaves, green lettuce leaves, red lettuce leaves, and Jerusalem artichoke roots, on the hemostatic system. Of all the tested extracts from the Asteraceae, dandelion root extract and dandelion fruit extracts appear to have the strongest anti-platelet potential in whole blood, while red lettuce leaves and Jerusalem artichoke roots demonstrated the strongest anti-platelet activity in washed blood platelets. Our results suggest that the members of the Asteraceae family, especially red lettuce leaves and Jerusalem artichoke roots, possess compounds that may exert beneficial anti-platelet effects. However, although Asteraceae plant organ extracts were found to demonstrate activity in vitro, further in vivo studies are needed to determine their true effects on cardiovascular disease.