Basil Cultivars Research Articles

Characterization of the floral traits, pollen micromorphology and DNA barcoding of the edible flowers from three basil taxa (Lamiaceae)

AbstractThe edible flowers sector is expanding due to the popularity and uses in culinary recipes of different species. In particular, flowers of Ocimum basilicum L. and related taxa are increasingly used for their aromas and nutritional value. However, there is limited information regarding their morphological characteristics and molecular profiles, which are both important to perform a quality control of food, and to avoid contaminations. Hence, our aim was the study of three basil taxa (O. basilicum ‘Cinnamon’, O. basilicum ‘Blue Spice’, and the hybrid O. × africanum Lour.) to obtain data useful for taxa identification and to understand which traits could be linked to their chemodiversity. The plants were grown in a greenhouse starting from seeds. Flowers were collected at anthesis; the morphology of calyxes, corolla and pollen grains was characterized; DNA barcoding analyses were performed. All taxa were identified only as O. basilicum by molecular analyses, but two haplotypes were distinguishable. All taxa were identifiable due to the presence/absence of specific glandular trichomes, and by pollen size and number of colpi. ‘Cinnamon’ and O. × africanum showed more morphological affinities to each other, but histochemical analyses suggested the separation of the three taxa. Pollen grains from ‘Cinnamon’ had the smallest diameter in polar view and were hexacolpate, while ‘Blue Spice’ pollen showed the highest diameter with grains being hexacolpate/octacolpate, similarly to O. × africanum. Our interdisciplinary study provides the first information for authenticating these basil cultivars in packaged products for human consumption.

Light extinction coefficient and radiation use efficiency of two greenhouse basil (ocimum basilicum L.) cultivars under deficit irrigation

ABSTRACT This two-year experiment with different planting seasons (April 2018 and August 2021) aimed to determine the effect of deficit irrigation (DI) levels (DI0: 100%, DI30: 70%, and DI60: 40% field capacity) on light interception, light extinction coefficient (k), dry biomass and radiation use efficiency (RUE) of two basil cultivars (Green and Purple). The greenhouse experiment was arranged in a split-plot design with three replications. The results showed that the k values ranged from 0.57 to 0.68 and 0.31 to 0.43 in April and August planting, respectively. The cumulative solar radiation interception, dry biomass, and RUE depended on DI levels, harvest numbers, and seasons. In two study years, dry biomass decreased and RUE increased with the reduction in irrigation water at all harvests and their total. Compared to DI0, basil dry biomass did not show a considerable decrease under DI30 in three harvests in April planting and in the first and second harvests in August planting. April planting had the higher cumulative solar radiation interception in the first and third harvest than the August planting. The basil dry biomass and RUE in the April planting were higher than those in the August planting at all three harvests and their total.

Sweet basil cultivars resistant to downy mildew evaluated under open field conditions

Sweet basil is the most widely grown herb in the U.S. Downy mildew is the most common disease. Management is necessary because there is no tolerance for disease symptoms on leaves marketed for fresh consumption. Host resistance is a preferred management practice. Research was initiated to evaluate cultivars bred to be resistant to downy mildew when they started to become commercialized. Five replicated experiments were conducted between 2018 and 2022 with field-grown basil exposed to naturally-occurring wind-dispersed sporangiospores of Peronospora belbahrii. Eleonora, which is one of the first resistant cultivars commercialized, exhibited limited suppression in this study (26 and 34% control based on AUDPC for incidence of leaves with symptoms compared to a susceptible cultivar). Amazel, the related cultivar Pesto Besto, and Prospera plus related cultivars from Genesis Seeds provided excellent to complete suppression (usually 100%). They have resistance gene Pb1. The four Rutgers DMR cultivars (Devotion, Obsession, Passion, and Thunderstruck) provided good to excellent control with some yearly variation (46–99% control). The recommended management program for downy mildew in field-grown sweet basil in an integrated management program with fungicides applied to resistant cultivar(s), plus weekly checking the crop for symptoms as well as staying current on knowledge about changes in the pathogen, commercialization of new resistant cultivars, and registration of new fungicides.

Evaluation of resistance in sweet basil cultivars against basil downy mildew

Evaluation of resistance in sweet basil cultivars against basil downy mildew

Comparative Transcriptome Analysis Revealed Candidate Gene Modules Involved in Salt Stress Response in Sweet Basil and Overexpression of ObWRKY16 and ObPAL2 Enhanced Salt Tolerance of Transgenic Arabidopsis.

Sweet basil (Ocimum basilicum L.) is an important aromatic plant with high edibility and economic value, widely distributed in many regions of the tropics including the south of China. In recent years, environmental problems, especially soil salinization, have seriously restricted the planting and spread of sweet basil. However, the molecular mechanism of the salt stress response in sweet basil is still largely unknown. In this study, seed germination, seedling growth, and chlorophyll synthesis in sweet basil were inhibited under salt stress conditions. Through comparative transcriptome analysis, the gene modules involved in the metabolic processes, oxidative response, phytohormone signaling, cytoskeleton, and photosynthesis were screened out. In addition, the landscape of transcription factors during salt treatment in sweet basil was displayed as well. Moreover, the overexpression of the WRKY transcription factor-encoding gene, ObWRKY16, and the phenylalanine ammonia-lyase-encoding gene, ObPAL2, enhanced the seed germination, seedling growth, and survival rate, respectively, of transgenic Arabidopsis, suggesting that they might be important candidates for the creation of salt-tolerant sweet basil cultivars. Our data enrich the study on salt responses in sweet basil and provide essential gene resources for genetic improvements in sweet basil in the future.

Phytochemical compositions and antioxidant activity of green and purple basils altered by light intensity and harvesting time

Ocimum basilicum L. is one of the most important medicinal and vegetable crops due to its essential oil, pleasant aroma and taste. In this study, we evaluated the impact of different light intensities, including 100 %, 50 %, and 30 % of natural sunlight, on the growth, phytochemical compositions, and antioxidant activity of green and purple basil cultivars at two different harvest times: early morning and noon. The height of the plant, number of leaves per plant, length of the petiole, diameter of the stem, and fresh and dry weight of the shoot were all reduced by decreasing light intensity in both basil cultivars. When the plants of both cultivars were grown under full light intensity and were sampled at noon, they showed the highest phenolic and flavonoid contents. The highest antioxidant activity was detected in purple basil cultivars grown under 30 and 50 % of sunlight in both harvests. The green basil cultivar showed the highest antioxidant activity when exposed to 30 % sunlight and harvested in the early morning. The highest essential oil content and yield in both basil cultivars were obtained under full sunlight in the early morning harvests. In summary, light intensity and harvest time influence the phytochemical yield, composition, and growth of two studied basil cultivars. Optimal results, particularly for medicinal purposes, were achieved by morning harvesting to maximize the essential oil yield of basils.

Biochemical and Molecular Characterization of Five Basil Cultivars Extract for Enhancing the Antioxidant, Antiviral, Anticancer, Antibacterial, and Antifungal Activities

Biochemical and Molecular Characterization of Five Basil Cultivars Extract for Enhancing the Antioxidant, Antiviral, Anticancer, Antibacterial, and Antifungal Activities

Optimização do crescimento in vitro e composição de óleos essenciais de cultivares de manjericão

Abstract The objective of this work was to evaluate the effect of the use of the Murashige & Skook (MS) and Linsmaer & Skoog (LS) media and of filter caps on culture flasks on the morphological and physiological characteristics of basil cultivars in vitro, as well as to determine the composition of the essential oil of plants acclimatized in pots. For the evaluation of the cultivation media, cultivars Anise, Cinnamon, Grecco a Palla, and Italian Large Leaf were used. The Anise, Cinnamon, Italian Large Leaf, and Maria Bonita cultivars were used for the evaluation of the use of filter caps. The composition of the essential oils of cultivars Anise, Cinnamon, and Italian Large Leaf was also evaluated. The basil seedlings showed a higher aerial-part dry mass and a lower hyperhydricity rate when grown in the MS medium. The flasks without filter caps produced seedlings with lower contamination rates. When acclimatized in pots, cultivars Limoncino and Anise presented the tallest plants with the largest crown diameters. In the composition of essential oils, methyl cinnamate and linalool stood out in cultivar Cinnamon, methyl chavicol in Anise, and linalool in Italian Large Leaf. In the in vitro cultivation, the evaluated cultivars present a higher aerial-part production in the MS medium and a lower contamination without the use of filters, whereas, in the pots, the composition of essential oils varies according to the cultivar.

Phenotypic Variations and Bioactive Constituents among Selected Ocimum Species.

Basil (Ocimum species) represents an extraordinary group of aromatic plants that have gained considerable economic importance, primarily due to their essential oils, which have applications in medicine, culinary, and perfumery. The Ocimum genus encompasses more than 60 species of herbs and shrubs originally native to tropical regions. This genus stands out for its remarkable diversity, displaying a wide spectrum of variations in phenotype, chemical composition, and genetic makeup. In addition to genetic factors, the growth, development, and essential oil production of basil are also influenced by environmental conditions, ontogeny, and various other factors. Consequently, the primary objective of this study was to explore the diversity in both the morphological characteristics and essential oil composition among basil genotypes preserved within the gene bank of the Hungarian University of Agriculture and Life Sciences' Department of Medicinal and Aromatic Plants. The investigation involved the assessment of fifteen basil genotypes, representing four distinct species: Ocimum basilicum (including 'Anise', 'Clove', 'Fino Verde', 'Licorice', 'Mammoth', 'Mrs. Burns', 'Thai tömzsi', 'Thai hosszú', and 'Vietnamese basil'), Ocimum sanctum (green holy basils), Ocimum citrodora (Lemon basil), and Ocimum gratissimum (African and Vana holy basil). The genotypes exhibited significant variations in their morphological growth, essential oil content (EOC), and composition. African basil produced more biomass (408.3 g/plant) and showed robust growth. The sweet basil cultivars clove, licorice, Thai tömzsi, and Thai hosszú also exhibited similar robust growth trends. Vietnamese basil, on the other hand, displayed the lowest fresh biomass of 82.0 g per plant. Both holy basils showed EOC levels below 0.5%, while Mrihani basil stood out with the highest EOC of 1.7%. The predominant constituents of the essential oil among these genotypes comprised estragole, thymol, methyl cinnamate, linalool, and eugenol. In conclusion, this study showed that the genotypes of basil stored in the department's gene bank exhibit a wide range of variability, both within and between species.

Quality and bioactive compound accumulation in two holy basil cultivars as affected by microwave-assisted hot air drying at an industrial scale

Holy basil (Ocimum Tenuiflorum L.) contains several bioactive compounds useful to the pharmaceutical and food industries. Microwave drying (MD) is a powerful technique for rapid drying of food or plant materials while preserving bioactive compounds during the process. However, little is known about the optimal combination of MD power with hot air drying (HAD) that can preserve the quality and yet only consume reasonable energy when drying holy basils. For that purpose, the effects of drying methods using MD combined with HAD at 45°C were examined to prevent losses in quality, antioxidant activities, and volatile flavor compounds in two holy basil cultivars (green and red cultivars). Holy basil leaves were dried at different MD powers of 200, 400, and 600 W combined with HAD and compared with a traditional tray drying (TD) at 45°C. Drying using MD at 600 W with HAD displayed significantly high levels of color retention, chlorophyll, and carotenoid content in both cultivars. The green cultivar showed a greater accumulation of total phenolic compounds (TPC), terpenoids, and DPPH free radical scavenging at 400 W with HAD. However, the red cultivar had the highest TPC, flavonoid, and terpenoid content at 600 W with HAD. The accumulation of major volatile organic compounds (VOCs) was also affected, and treatment at 600 W exhibited the highest methyl eugenol and β-caryophyllene content in both cultivars. The use of the highest power of MD (600 W) with HAD for leaf drying reduced the effective drying time and energy consumption among both cultivars. Taking into consideration the dried quality of antioxidant accumulation and energy consumed for drying, we recommend using MD at 400 or 600 W with HAD for the green cultivar and 600 W for the red.

Shade Nets Reduced Growth, Nutrition, and Sugars of Hydroponic Lettuce and Basil

Colored shade nets are known to alter the light quality and quantity and thus can influence plant growth and nutritional quality of crops. Lettuce (‘Lollo Antonet’ and ‘Green Forest’) and basil (‘Aroma-2’ and ‘Genovese’) were grown in ebb-and-flow hydroponic tables for 4 weeks. Colored shade nets of aluminet, black, pearl, and red with 50% shading intensity along with a control (no-shade) were used in this experiment. Data for plant growth and leaf quality attributes were collected at harvest time. The no-shade treatment showed increased shoot fresh and dry weight, sugar, and relative chlorophyll content in both lettuce and basil cultivars, whereas plant height and net photosynthesis rates were increased under aluminet, pearl, and red nets. In basil, calcium and sulfur were greatest under no-shade, whereas zinc and copper were greatest under aluminet. Zinc, iron, calcium, magnesium, and manganese concentrations were greatest under no-shade in lettuce. The pearl-colored net increased leaf soluble solids content. No-shade produced the greatest starch values in basil, whereas pearl shade net produced the greatest starch in ‘Lollo Antonet’ in the fall. Light spectra varied with shade net resulting in 90%, 65%, 50%, 30%, and 70% of incident light occurring between 400 and 700 nm for no-shade, pearl, aluminet, black, and red shade nets, respectively. Overall, lettuce and basil plants under no-shade (daily light integral of 20 to 24 mol·m−2·d−1 and temperature of 26 to 30 °C) had increased plant growth and leaf quality in late spring and fall, compared with colored shade nets.

Evaluation of basil (Ocimum basilicum) accessions under different drought conditions based on yield and physio-biochemical traits

BackgroundBasil is one of the most famous herbs, which has broad usage as a fresh vegetable and therapeutic and pharmaceutical services. The main abiotic stress limiting basil production globally is drought. As a result, appropriate drought screening-which effectively separates high-yielding but drought-sensitive genotypes from drought-tolerant genotypes-is necessary for the optimal selection of high-yielding basil cultivars under drought stress conditions. So, a split plot experiment with three replications based on a completely randomized design were carried out in a pot under field conditions for this investigation. Water levels (full irrigation or control, moderate stress, and severe stress) were assigned as main plots, while 22 basil accessions were given as sub-plots. In this study, leaf yield as well as physio-biochemical traits had measured on accessions.ResultsOur results revealed large variation in yield, essential oil (%), protein, proline, chlorophyll, total phenol and flavonoids traits across the 22 accessions. The percentage of leaf yield reduction in moderate drought stress than normal conditions showed that G1 (−6.5%), G17 (−7.05%), G20 (−9.01%), and G12 (−10.9%) accessions had the least changes, respectively. Although in severe drought stress than normal conditions, the G1 (−32.01%), G12 (−33.12%), G4 (−33.24%), G7 (−34.11%), and G17 (−34.93%) accessions had the least amount of change in plant leaf yield, respectively. Furthermore, the highest yield reduction occurred in moderate and severe stress conditions in G18 (−25.36%) and G8 (−42.98%) accessions, respectively. Cluster analysis based on the ward method in both conditions (moderate and severe drought conditions) placed the accessions in three groups, and accessions were identified as tolerant, whose average traits in that group were higher than the total average. The principal component analysis also showed that in moderate drought conditions, the first two components explained about 95.28% of the total variation, while in severe drought conditions, these two components explained about 96.37% of the total variation.ConclusionsThe different multivariate analyses (cluster analysis, PCA, mean comparison) were used to identify tolerant and sensitive accessions based on all traits. The accessions G3, G4, G6, and G7 were found to be tolerant to stress, while G10, G15, G16, and G20 were found to be sensitive to drought. These accessions are a useful step in producing drought-tolerant, high-yielding accessions and can be utilized in breeding programs for basil.

Urinary Excretion of Mercapturic Acids of the Rodent Carcinogen Methyleugenol after a Single Meal of Basil Pesto: A Controlled Exposure Study in Humans.

Methyleugenol (ME), found in numerous plants and spices, is a rodent carcinogen and is classified as "possibly carcinogenic to humans". The hypothesis of a carcinogenic risk for humans is supported by the observation of ME-derived DNA adducts in almost all human liver and lung samples examined. Therefore, a risk assessment of ME is needed. Unfortunately, biomarkers of exposure for epidemiological studies are not yet available. We hereby present the first detection of N-acetyl-l-cysteine conjugates (mercapturic acids) of ME in human urine samples after consumption of a popular ME-containing meal, pasta with basil pesto. We synthesized mercapturic acid conjugates of ME, identified the major product as N-acetyl-S-[3'-(3,4-dimethoxyphenyl)allyl]-l-cysteine (E-3'-MEMA), and developed methods for its extraction and LC-MS/MS quantification in human urine. For conducting an exposure study in humans, a basil cultivar with a suitable ME content was grown for the preparation of basil pesto. A defined meal containing 100 g of basil pesto, corresponding to 1.7 mg ME, was served to 12 participants, who collected the complete urine at defined time intervals for 48 h. Using d6-E-3'-MEMA as an internal standard for LC-MS/MS quantification, we were able to detect E-3'-MEMA in urine samples of all participants collected after the ME-containing meal. Excretion was maximal between 2 and 6 h after the meal and was completed within about 12 h (concentrations below the limit of detection). Excreted amounts were only between 1 and 85 ppm of the ME intake, indicating that the ultimate genotoxicant, 1'-sulfooxy-ME, is formed to a subordinate extent or is not efficiently detoxified by glutathione conjugation and subsequent conversion to mercapturic acids. Both explanations may apply cumulatively, with the ubiquitous detection of ME DNA adducts in human lung and liver specimens arguing against an extremely low formation of 1'-sulfooxy-ME. Taken together, we hereby present the first noninvasive human biomarker reflecting an internal exposure toward reactive ME species.

Differential Antioxidant Response to Supplemental UV-B Irradiation and Sunlight in Three Basil Varieties.

Three basil plant varieties (Ocimum basilicum var. Genovese, Ocimum × citriodorum, and Ocimum basilicum var. purpurascens) were grown under moderate light (about 300 µmol photons m-2 s-1) in a glasshouse or growth chamber and then either transferred to an open field (average daily dose: 29.2 kJ m-2 d-1) or additionally exposed to UV-B irradiation in a growth chamber (29.16 kJ m-2 d-1), to reveal the variety-specific and light-specific acclimation responses. Total antioxidant capacity (TAC), phenolic profile, ascorbate content, and class III peroxidase (POD) activity were used to determine the antioxidant status of leaves under all four light regimes. Exposure to high solar irradiation at the open field resulted in an increase in TAC, total hydroxycinnamic acids (HCAs, especially caffeic acid), flavonoids, and epidermal UV-absorbing substances in all three varieties, as well as a two-fold increase in the leaf dry/fresh weight ratio. The supplemental UV-B irradiation induced preferential accumulation of HCAs (rosmarinic acid) over flavonoids, increased TAC and POD activity, but decreased the ascorbate content in the leaves, and inhibited the accumulation of epidermal flavonoids in all basil varieties. Furthermore, characteristic leaf curling and UV-B-induced inhibition of plant growth were observed in all basil varieties, while a pro-oxidant effect of UV-B was indicated with H2O2 accumulation in the leaves and spotty leaf browning. The extent of these morphological changes, and oxidative damage depended on the basil cultivar, implies a genotype-specific tolerance mechanism to high doses of UV-B irradiation.

Analysis of Antioxidant Capacity Variation among Thai Holy Basil Cultivars (Ocimum tenuiflorum L.) Using Density-Based Clustering Algorithm

Holy basil (Ocimum tenuiflorum L.) is a widely renowned herb for its abundance of bioactive compounds and medicinal applications. Nevertheless, there exists a dearth of knowledge regarding the variability among holy basil cultivars capable of yielding substantial bioactive compounds. This study aims to address this gap by shedding light on the diversity of antioxidant capacities within different accessions of Thai holy basil by employing a density-based clustering algorithm to categorize the holy basil cultivars that demonstrate notable antioxidant potential. The study involves the analysis of the anthocyanin, flavonoid, phenolic, and terpenoid content, as well as DPPH antioxidant activity, in 26 Thai holy basil accessions collected from diverse locations in Thailand. Among the 26 tested Thai holy basil cultivars, terpenoids were found to be the dominant class of compounds, with average values of 707 mg/gDW, while the levels of flavonoids and phenolic compounds remained below 65 mg rutin/gDW and 46 mg GAE/gDW, respectively. The DPPH assay in holy basil cultivars demonstrated that the antioxidant activity ranged between 50% and 93%. After standardizing the data, the clustering results revealed four distinct groups of cultivars: the first group, with low antioxidant levels; the second group, with high terpenoid content; the third group, with high flavonoid, DPPH antioxidant activity, and phenolic content; and the fourth group, with elevated levels of anthocyanin, DPPH antioxidant activity, and phenolic content. A strong positive correlation was observed among DPPH antioxidant activity, flavonoids, and phenolics. Specific cultivars: The Red, OC108, and OC106 holy basil cultivars in cluster 4 exhibited high anthocyanin and phenolic production. In cluster 3, the accessions OC113, OC057, OC063, and OC059 showed high DPPH antioxidant activity, flavonoids, and phenolics, while, in cluster 2, only accessions from Udon Thani, Thailand—namely OC194 and OC195—displayed high terpenoid content. Ultimately, this study significantly contributes to the inherent diversity in the antioxidant capacities among various Thai holy basil cultivars. It lays the foundation for targeted breeding strategies and informed choices regarding consumption. The comprehensive insights from this analysis hold the potential to accurately identify holy basil cultivars with promising applications in medicine, functional foods, and the nutraceutical industry.

Identification of variety-specific metabolites of basil by high performance thin layer chromatography-assisted metabolic profiling techniques

The technological advances of analytical instrumentation and techniques has laid the ground for the rapid expansion of metabolomics or in a wider sense, untargeted analysis applied to life sciences themes. However, the objective of identifying all existing metabolites within organisms remains a daunting challenge. All analytical techniques exhibit varying degrees of sensitivity and versatility for the detection of metabolites and none of the existing analytical platforms can be expected to be ideal for exhaustive chemical profiling. Planar liquid chromatography, and in particular, high performance thin layer chromatography (HPTLC), has been used for chemical profiling of natural products in conjunction with metabolomics. HPTLC has specific advantages which include its ability to generate reliable chemical fingerprinting data and facilitate preparative work for metabolite isolation during later stages of metabolomics analysis. In this study, we investigated the chemical profiles of four commercially available basil cultivars, namely Dolly, Emily, Keira, and Rosie. We used HPTLC as the primary analytical tool for the separation of basil cultivars based on detected metabolites, and then compared the results with those obtained with other analytical platforms. We identified the characteristic marker compounds of each basil cultivar from the HPTLC plates and validated their potential using LC-MS and GC-MS analyses as a metabolomics tool. Firstly, we compared the HPTLC data of the four cultivars, obtained with two systems that used silica gel 60 and two mobile phases composed of toluene-EtOAc (8:2, v/v) and EtOAc-formic acid-acetic acid-water (100:11:11:27, v/v), with 1H NMR data to evaluate their separation power. Despite providing lower resolution and detecting fewer compounds, the HPTLC separation power was comparable, and in some cases even better than that of 1H NMR. Additionally, we investigated the potential of HPTLC as a tool for chemical fingerprinting and demonstrated its suitability for preparative purposes that are essential for identifying metabolites in mixture analysis. Metabolites were easily isolated from sample mixtures, and identified with the assistance of GC-MS, LC-MS, and TLC-densitometry.. Several marker compounds were thus identified, including 2,4 di-tertbutylphenol, palmitic acid, hexadecanamide, 9-octadecenamide, squalene, hentriacontane, methyl 3-(3,5-ditert‑butyl‑4-hydroxyphenyl)propanoic acid, sagerinic acid, and cyanidin-3-O-sophoroside.

Balancing Yield and Antioxidant Capacity in Basil Microgreens: An Exploration of Nutrient Solution Concentrations in a Floating System

The appropriate concentration of the nutrient solution (NS) plays an important role in the yield, antioxidant capacity, and biochemical compounds of basil microgreens in the floating system. This study examined the impact of five different concentrations of Hoagland’s NS (25%, 50%, 75%, 100%, and 125%) on the antioxidant capacity, biochemical compounds, and yield of four basil cultivars and genotypes (Persian Ablagh, Violeto, Kapoor and Red Rubin) in a floating system, utilizing a split plots designs. Results revealed that the highest yield was achieved with a 50% NS concentration. The Persian Ablagh genotype, under a 125% NS concentration, exhibited the highest content of carotenoids, flavonoids, phenolic compounds, and antioxidant potential index (APCI). The Violeto cultivar at a 100% NS concentration produced the highest amounts of vitamin C and anthocyanin. The Kapoor cultivar, when grown with a 100% NS concentration, demonstrated the greatest antioxidant capacity. The nutrient solution with 125% concentration compared to 50% concentration reduced the yield by 23.29%. Also, the performance of the Violeto cultivar increased by 36.24% compared to the red variety of Robin. According to the APCI index, the genotype of Iranian Ablaq basil increased by 152.79% in the treatment of nutrient solution with a concentration of 125% compared to 50%. In this study, yield and total chlorophyll showed a significant negative correlation. A significant positive correlation was observed between vitamin C content and flavonoids, anthocyanin, phenolic compounds, and antioxidant capacity. Anthocyanin content exhibited a positive and significant correlation with the APCI. Based on these findings, we recommend a 50% NS concentration of Hoagland’s NS for optimal yield, a 125% NS concentration for the production of secondary metabolites with enhanced antioxidant capacity, and a 100% NS concentration as a balance between antioxidant properties and yield for basil microgreens production in a floating system.

Vacuolar localisation of anthocyanin pigmentation in microgreen cotyledons of basil, cabbage and mustard greens does not impact on colonisation by Shiga-toxigenic Escherichia coli O157:H7

Microgreens, the immature plants harvested after a few weeks of growth, are perceived as a heathy, nutritious food ingredient but may be susceptible to colonisation by human pathogens including Shiga-toxigenic Escherichia coli (STEC). Some microgreen cultivars accumulate anthocyanins or secrete essential oils which, when extracted or purified, have been reported to inhibit bacterial growth. Therefore, the impact of anthocyanins on bacterial colonisation by STEC (Sakai) was compared for three species that have pigmented cultivars: basil (Ocimum basilicum L.), cabbage (Brassica oleracea L.) and mustard greens (Brassica juncea L.). Inoculation with low concentrations of STEC (Sakai) (3 log10 colony forming units/ml (CFU/ml)) during seed germination resulted in extensive colonisation at the point of harvest, accumulating to ∼ 8 log10 CFU/g FW in all cultivars. Bacterial colonies frequently aligned with anticlinal walls on the surface of epidermal cells of the cotyledons and, in basil, associated with peltate and capitate gland cells. Crude lysates of pigmented and non-pigmented basil cultivars had no impact on STEC (Sakai) growth rates, viability status or biofilm formation. Anthocyanins are located within plant vacuoles of these microgreen cultivars and did not affect colonisation by STEC (Sakai) and pigmentation therefore cannot be considered as a controlling factor in bacterial interactions.

Efficacy of Organic Fungicides for Downy Mildew in Field-Grown Sweet Basil.

Downy mildew is a common, widespread disease affecting basil leaves. No tolerance for disease symptoms, especially on leaves for fresh consumption, necessitates management. Six replicated experiments were conducted between 2010 and 2016 with field-grown basil of a susceptible cultivar exposed to naturally occurring, wind-dispersed sporangiospores of Peronospora belbahrii to evaluate fungicides approved for use on organically produced crops and products in development. Products tested currently registered for use on basil in the U.S. and labeled for downy mildew were Actinovate (Streptomyces lydicus), Companion (Bacillus subtilis), Cueva (copper octanoate), Double Nickel (Bacillus amyloliquefaciens), Forticept EP #1 (thyme oil), Milagrum Plus (Bacillus subtilis), Organocide (sesame oil), Oso (polyoxin D zinc salt), OxiDate (hydrogen dioxide), Procidic (citric acid), Regalia (Reynoutria sachalinensis extract), Stargus (Bacillus amyloliquefaciens), and Trilogy (neem oil). Most are biopesticides. A conventional fungicide, Revus (mandipropamid), was included in most experiments as a positive control. Applications were made weekly to foliage with a backpack sprayer starting before symptoms were seen, except in 2013 when disease onset was early and 2015 when applications were made twice weekly. Organic treatments tested in 2013 started with a soil drench application around the base of plants two days after transplantation. Fungicide efficacy was assessed based on incidence of symptomatic leaves rather than disease severity because there is no tolerance for disease on fresh-market herbs. None were effective based on weekly severity assessments or AUDPC values, confirming results from other researchers that downy mildew cannot be effectively managed with organic fungicides applied to susceptible basil cultivars.

Bioprospecting of Five Ocimum sp. Cultivars from Croatia: New Potential for Dietary and Dermatological Application with Embryotoxicity Tests.

Ocimum basilicum L. is the most common Ocimum species, and it is used as an ornamental plant and in food condiments. This unique study examined the chemical composition and biological activities of six extracts from five basil cultivars, including their antimicrobial, antidiabetic, antilipidemic, neuroprotective, and anticollagenase activity. Moreover, their toxicological effects were studied using the zebrafish Danio rerio. Volatile components were determined using HS-SPME and GC-MS, while total polyphenols were detected using HPLC and the spectrophotometric Folin-Ciocalteu method. Spectrophotometric assays (DPPH, ABTS, ORAC, FRAP) were performed to determine antioxidant activity, collagenase inhibition, acetylcholinesterase inhibition, and pancreatic lipase inhibition. Antimicrobial activity was determined using the broth microdilution test. The study found that the biological activities of different basil cultivars varied depending on the proportion of active compounds, as determined by chemical analyses. All six basil extracts significantly inhibited α-amylase, while Purple basil extract most significantly inhibited the activity of collagenase, acetylcholinesterase, and pancreatic lipase. Purple basil and Dark Opal basil I extracts exhibited the highest antimicrobial activity, while the Dark Opal basil II extract had the most significant antioxidant potential. The findings in this study suggest that ethanolic basil extracts have the potential to be used as dietary drugs and implemented in antiaging products. This study is unique in its aims to compare the chemical composition and biological activities of basil cultivars from Croatia and to evaluate potential toxicological effects through embryotoxicity tests on zebrafish Danio rerio embryos, and it reports the first evidence of anticollagenase, antidiabetic, and antilipidemic activities for these cultivars.