Broccoli Inflorescences Research Articles

Performance Test of Artificial Defoliating Broccoli Conveyor Line and Analysis of Defoliating Broccoli Inflorescences

There is a close relationship between stem and leaf biological characteristics of mature broccoli plants and defoliation technology. Morphological parameters such as the spread degree and diameter of cauliflower stem and leaf and the connection performance of cauliflower stem and leaf were studied. These experiments are helpful to the research of defoliation devices and methods for large-scale manual transportation lines. In this paper, according to the damage forms that may be suffered in the separation process of mature broccoli stems and leaves, “sunny” broccoli varieties were selected. Firstly, the mechanical properties of mature broccoli stems were obtained through different loading methods such as stretching, compression, shearing and bending. Secondly, the stress relaxation characteristics of broccoli were analyzed by static compression of broccoli flower balls. Finally, the separation method of broccoli stems and leaves was simulated by ANSYS. The simulation results showed that shear fracture was more suitable for stem and leaf separation of broccoli than tensile fracture. Then, aiming at the separation of stems and leaves of broccoli, an artificial broccoli assembly line was proposed to ensure the efficiency of leaf removal through man–machine cooperation. The dynamic characteristics of the belt of broccoli leaf removal line were studied to ensure the efficient and stable operation of the conveyor system of broccoli artificial leaf removal line.

Macro-and microelement composition of dry extract of Brassica oleracea var. italica Plenck

Thus, our research significantly expands information about the chemical composition of raw materials from plants of the genus Brassica Oleracea and provides theoretical justification for the possibility of complex use of medicinal plants, taking into account environmental factors. In the studied sample of broccoli inflorescences, 29 elements were identified and their quantitative content. Based on the study, we can conclude that broccoli – Brassica oleracea L. var. italica Plenck is not only a valuable food crop, but also a medicinal plant – a source of macro- and microelements. The object under study is of interest for an in-depth study of its chemical composition in order to create regulatory documentation for plant raw materials.

Cauliflower and broccoli floretting machine

Abstract
 Florets are the main edible parts of cauliflowers and broccoli, but stalks and leaves are also used in the production of vegetable soup mixes. In industrial processing lines, large cauliflower and broccoli inflorescences have to be separated into smaller florets with a diameter of 2 to 6 cm. Simple and inexpensive machines for floretting cauliflowers and broccoli, including devices that can be used in small-scale production, are in short supply on the market. Therefore, the aim of this study was to design a floretting machine composed of a load-bearing frame, a processing table, a crushing chamber and a horizontal conveyor. In the first stage of the process, one of the two conical knives is used to separate florets and leaves from stalks. The stalks fall into a container under the processing table, and the leaves are picked manually from the material on the table and are placed in a separate container. In the second stage, the separated florets are manually fed into the crushing chamber where larger florets are separated into smaller parts. The crushing chamber is composed of a rotating crushing roller and a fixed screen at the bottom. Florets that have been cut into the appropriate size pass through the screen and fall onto a conveyor belt under the crushing chamber. The quality of the floretting process can be inspected visually by the operator, and impurities or excessively damaged florets can be removed from the conveyor belt. In the final stage, the separated florets are transported to a container. The designed machine can be operated directly on the farm; therefore, the resulting produce is fresher than products that are transported and separated in a food processing plant

Toxic Metals in Broccoli by Combined Use of Acidity Correctives and Poultry Litter Under Mountain Tropical Conditions.

The current study was developed to evaluate agronomic efficiency and food security of isolated or simultaneous use of two residues-steel slag and fresh or composted poultry litter-in the cultivation of broccoli (Brassica oleracea var. italica). The composition and contribution of toxic and potentially toxic metals by different treatments and contents, translocation, and accumulation of Pb, Cd, Cu, Fe, Mn, and Zn in different plant organs were analyzed. Then, risks to human health associated with consumption of inflorescences were based on the indices of estimated daily intake, noncarcinogenic target hazard quotient, total hazard index (THI), and carcinogenic risk factor (CR), considering adults and children. Steel slag was similar to limestone in terms of the corrective effect of acidity and, despite containing toxic metals, it did not contribute to their higher translocation to inflorescences. Composting favored the concentrations of Pb, Cu, and Zn in poultry litter. The combined use of steel slag and fresh poultry litter and, mainly, composted poultry litter, favored absorption and translocation of Pb for inflorescences, that is, 60.37% and 66.13% of all Pb absorbed, respectively. Consumption of inflorescences from these treatments resulted in the critical THI values of 1.03 and 1.52, respectively, with Pb and Cd being the metals that mostly contributed to the risk. The registered CR was higher than the threshold level of 10-6. The use of steel slag associated with poultry litter favors contamination of broccoli inflorescences and increases risks to human health due to their consumption.

Влияние агрохимикатов на пространственно-временные изменения агрохимических свойств почвы и урожай брокколи

The aim of the study. The aim of the study was to examine the effect of agrochemicals (mineral and organo-mineral fertilizers, plant growth regulators and ameliorants) on the spatio-temporal changes in the properties of agro-gray soil and broccoli yield using a cartographic approach. Methodology. The field experiment was conducted in 2016 at the site located near the Bykovo village in the south-east of West Siberia (54°58 '02.8" N; 83°5'21.45" E, Novosibirsk region). The objects of the study were the agro-gray soil (Luvic Retic Greyzemic Phaeozem (Siltic, Aric)) and the medium-ripe broccoli cabbage variety "Linda". The experiment scheme included the following treatments: (1) Control (without fertilizers), (2) Background (N100P60K160), (3) Background + succinic acid, (4) Background + dolomite, (5) Background + mulch, (6) Organo- mineral fertilizer "Criall". Soil samples were analyzed for the content of organic carbon, nitrates, total, mineral and organic phosphorus, as well as its mobile form; exchangeable potassium, calcium and magnesium, and pH. The dried samples of broccoli inflorescences were analyzed for the total content of nitrogen, phosphorus, potassium, calcium and magnesium. Main results. After applying agrochemicals and harvesting broccoli, the variation coefficients of рН, mobile phosphorus, potassium and calcium increased by two or more times. The use of agrochemicals increased the yield and improved the nutritional value of broccoli inflorescences. The treatments with mineral fertilization (2, 3, 4 and 5) the treatment 2 (Background N100P60K160) provided the greatest return. The application of the studied agrochemicals resulted in the negative (acidification, binding of phosphorus, calcium and magnesium) and positive (increase in the content of elements) effects. The immobilization of nutrients (phosphorus, calcium, magnesium) in poorly soluble soil compounds and the respective decrease in the content of the elements’ mobile forms did not have a negative effect on the elemental composition of broccoli inflorescences. Thus, chemical immobilization, leading to the fixation of nutrients in the upper soil horizon, prevents their leaching by melt- and rainwater into the lower horizons.

Growth, yield and biochemical constituents as well as post-harvest quality of water-stressed broccoli (Brassica oleraceae L. var. italica) as affected by certain biomodulators

The present study was conducted to assess the effect of certain biomodulators (BMs) on growth, yield, and storability as well as on bioactive constituents either before or after storage of deficit-irrigated broccoli. The tested BMs were yeast extract (YE), moringa leaves extract (MLE), salicylic acid (SA) and humic acid (HA). Deficit irrigation (DI) was achieved by extending the duration between subsequent irrigations from five days (control) to either ten (IR10) or 15 days (IR15). Results indicated that all applied BMs alleviated DI effects on growth and yield. Post-harvest decline in quality was delayed by DI as biomass loss percentage (BLP %) and post-harvest decay percentage (PHD %) were decreased. All applied BMs also preserved inflorescence quality during storage as BL% and PHD% were lower in BMs-treated plants compared with control. Chlorophylls, carotenoids, ascorbic acid, total phenols and total soluble carbohydrates in broccoli inflorescence were decreased in IR10 and IR15 plants whereas increased in BMs-treated plants. Anthocyanins content was not significantly affected in response to DI treatments and peroxidase activity was not significantly affected in response to either DI or BMs treatments. It was concluded that treatments with BMs could be a feasible approach to avoid yield losses in water-stressed broccoli and that treatments with BMs of deficit-irrigated plants maintain post-harvest quality of broccoli heads during storage.

The degradation of chloroplast components during postharvest senescence of broccoli florets is delayed by low-intensity visible light pulses

Abstract Senescence in harvested green organs, such as broccoli inflorescences, is a highly regulated process characterized by a massive degradation of chloroplast components. The dismantling of the chloroplast involves small “senescence-associated vacuoles” (SAVs) with high protease activity. The expression of the senescence associated gene, SAG12 (here BoSAG12), which encodes a senescence associated cysteine protease, correlated with SAVs appearance. One environmental factor that delays senescence is low-intensity visible light. Daily irradiation with pulses of 2 h of low-intensity white light (20–25 μmol m−2 s−1) is a promising technology to delay postharvest senescence of broccoli stored at room temperature. The aim of this study was to analyze the effects of low-intensity white (W) and red (R) light treatments on some events related to chloroplast dismantling during postharvest senescence of broccoli inflorescences. We detected that chloroplasts number did not change during postharvest senescence. We found that SAVs participate in the dismantling of chloroplasts during the postharvest senescence of broccoli florets. SAVs appearance occurred earlier than visible yellowing. The two light treatments used, i.e. pulses of low-intensity W and R light, delayed chloroplast changes, including chlorophyll degradation and SAVs appearance. The delay of SAVs appearance was accompanied by the delay of BoSAG12 induction in broccoli florets. Regarding protein degradation, not all proteins analyzed were affected equally. The light treatments had greater effect on the retention of thylakoid proteins than on Rubisco and apparently, the effects of light treatment were higher on proteins from PSII (LHCII) than on those from PSI (LHCI and PsaA).

Olive tree pruning derived biochar increases glucosinolate concentrations in broccoli

Biochar has attracted great attention in the soil scientific community for its interaction with different biogeochemical cycles and its potential environmental and agronomical benefits. However, there is only limited information about its effect on plant secondary metabolism. In this manuscript, a biochar produced from olive tree pruning by slow pyrolysis at 600 °C was selected to analyze its impact on the concentration of the health-promoting compounds glucosinolates (GLSs) in broccoli. The biochar was applied as soil amendment, alone or combined with organic and mineral fertilization, in a broccoli cultivar in the field. We found that this particular biochar caused an enrichment in GLSs concentration in broccoli amended with biochar alone. Meanwhile, the fertilized treatments caused a decrease in the GLSs concentration in broccoli inflorescence, particularly mineral fertilization originated the lowest concentration of neoglucobrassicin and glucoraphanin. When biochar was combined with mineral fertilization it increased the concentration of GLS to similar levels as the untreated plants, probably as a physiological response of the plant to the enhanced physicochemical properties of biochar amended soils. These findings highlight the importance of agronomical practices in achieving a balance between a good performance in production and the presence of beneficial phytochemicals.

Optimisation of Transplant Age in Combination with Dark-chilling to Enhance the Biological Quality of Broccoli Cultivated in Summer

Under field conditions, crops are exposed simultaneously to more than one environmental stress factor. Controlled abiotic stress applied at the transplant stage can be used as a tool for inducing stress memory, improving stress tolerance after transplanting, and enhancing the nutraceutical value of the yield. The aim of present study was to determine the effect of dark-chilling at 2 °C for 1 and 2 weeks on the tolerance of broccoli seedlings of various ages against adverse conditions in the field and the chemical composition of the inflorescences. Two separate planting programmes were undertaken in the summer. In general, planting delay by about 1 month resulted in an increase in dry weight of about 3%, ascorbic acid (38%), soluble sugars (18%), K (14%), P (13%), Zn (12%), Fe (8%), and Mn (9%) in broccoli inflorescences. Planting of young, 4-week-old seedlings resulted in higher ascorbic acid content in broccoli inflorescences of about 15%, soluble sugars (7%), K (5%), P (6%), Mg (4%), Na (11%), and Zn (3%) in broccoli inflorescences as compared to 10-week-old ones. Chilling of seedlings for two weeks caused an increase in dry weight in broccoli inflorescences of about 6%, ascorbic acid (15%), soluble sugars (12%), K (2%), P (2%), Mg (5%), Zn (3%), Fe (4%), and Mn (6%) as compared to the non-chilled control. The results indicated that the age of the seedlings and dark-chilling influenced the level of chemicals related to taste and biological value of broccoli inflorescences in a complex way. There was no general superiority or interaction of any of the experimental factors affecting all health-related compounds. Dark-chilling can be considered as a practice of broccoli seedling management before transplanting, positively affecting some yield parameters through stress memory induction.

High dilution preparations for organic production system of broccoli

The aim of this study was to evaluate the influence of high dilution preparations on seedlings growth and production of broccoli under organic system. Three experiments were conducted in a greenhouse with completely randomized design. Two others experiments were conducted under field conditions, and the experimental design was randomized in blocks. Both designs were done with four replications and nine treatments. The treatments consisted of high dilution preparations of Arnica montana, Silicea terra, Carbo vegetabilis and Sulphur at 6CH or 30CH, water was used as control. In greenhouse, plant height, root length and stem diameter of seedlings were evaluated, along with the fresh and dry mass of shoot and root. In field, fresh and dry mass of inflorescences, plant heigh and stem diameter were evaluated. Silicea terra at 30CH increased the stem diameter, root length and dry mass of shoot and root in the broccoli seedlings. Sulphur at 6CH increased the fresh and dry mass of broccoli inflorescences. Silicea terra at 6CH, Carbo vegetabilis, and Sulphur at 30CH increased the plant height in field experiments. This suggests that high dilution preparations can be utilized to increase the biomass production and others desirable characteristics of broccoli crop under organic system.

Effect of Different Thawing Conditions on the Concentration of Bioactive Substances in Broccoli (B rassica oleracea var. A venger )

Thawing is a complex process that changes the physical and chemical conditions of a substance and can significantly affect the quality of food. Thus, this study aimed to evaluate the effect of different thawing conditions (room temperature, refrigerated temperature and microwave) on the content of bioactive compounds in broccoli (Brassica oleracea var. Avenger) and identify which method provides better retention of these substances. In methodology, carotenoids, flavonoids and vitamin C were analyzed by high-performance liquid chromatography; phenolic compounds and chlorophylls were analyzed by spectrophotometer. The results showed that thawing in a microwave retained the chlorophylls “a” (1,084 μg/g), “b” (367 μg/g) and “total” (1,451 μg/g), total phenolics (1,226 mg/100 g) and quercetin (117 mg/100 g). Thawing at room temperature retained more kaempferol (397 mg/100 g) and β-carotene (8,847 μg/100 g). Thawing at refrigerated temperature yielded higher concentrations of vitamin C (792 mg/100 g). Practical Applications Freezing of vegetables is widely used in large businesses and restaurants. With this, thawing of vegetables is an important step because bioactive nutrients can be lost. The results of this study showed that thawing in microwave is the most suitable for those who choose to thaw the broccoli inflorescences and cooking it later, because the smallest losses of bioactive compounds were observed in this method of thawing.

Carotenoids, flavonoids, chlorophylls, phenolic compounds and antioxidant activity in fresh and cooked broccoli (Brassica oleracea var. Avenger) and cauliflower (Brassica oleracea var. Alphina F1)

Vegetables from the family Brassicaceae are excellent sources of bioactive phytochemicals and may reduce the risk of chronic diseases. Cooking of vegetables can improve the bioavailability of some of these compounds. We evaluated the extractability of carotenoids, flavonoids, phenolic compounds and chlorophylls in fresh inflorescences of broccoli and cauliflower and subjected to different cooking conditions. Boiled broccoli inflorescences had higher concentrations of bioactive compounds than other cooking methods do, due to the high temperature and short cooking time. Fresh and microwaved cauliflower retained phenolic compounds (1750 and 1792 mg/100 g) and quercetin, whereas boiling retained more 2192 μg/100 g of β-carotene and 168 μg/100 of vitamin A and steaming produced higher concentrations of lutein (1197 μg/100 g), 88.6 μg/100 g of zeaxanthin, 152 μg/100 g of cryptoxanthin, 86.6 μg/100 g of α-carotene and 3174 μg/100 g of total carotenoids. Cooking can, in some cases, improve the extractability of bioactive compounds in vegetables.

Postharvest senescence of florets from primary and secondary broccoli inflorescences

The shelf-life of fresh-cut vegetables may be markedly affected by the type and quality of the raw materials. In this work we evaluated the influence of the type of inflorescence used for processing (primary and lateral) on the postharvest senescence of refrigerated fresh-cut broccoli. Florets from primary and lateral heads were cut and washed with chlorinated water, rapidly cooled to 4°C, packed in plastic trays covered with perforated PVC and stored at 4°C for 0, 14 or 21d. During storage we evaluated floret deterioration, respiration rate, weight loss, color, chlorophyll content, sugars (glucose, fructose and sucrose), antioxidant capacity against ABTS+ and DPPH radicals, ascorbic acid and Folin–Ciocalteu-reacting substances. Florets from lateral inflorescences were more perishable than fresh-cut broccoli obtained from primary heads. Terminal florets retained higher chlorophyll levels and showed delayed yellowing. Already at harvest primary-broccoli showed lower respiration rate. Florets form terminal heads showed lower weight and sugar loss during storage and maintained higher visual quality throughout the storage period at 4°C. The inflorescence type also had large impact in the initial level of antioxidants as well as in their metabolism during storage. This information may be useful for vegetable processors.

Ultrasonic-assisted enzymatic extraction of phenolics from broccoli (Brassica oleracea L. var. italica) inflorescences and evaluation of antioxidant activity invitro.

An efficient ultrasonic-assisted enzymatic extraction technique was applied to extracting phenolics from broccoli inflorescences without organic solvents. The synergistic model of enzymolysis and ultrasonication simultaneously was selected, and the enzyme combination was optimized by orthogonal test: cellulase 7.5 mg/g FW (fresh weight), pectinase 10 mg/g FW, and papain 1.0 mg/g FW. The operating parameters in ultrasonic-assisted enzymatic extraction were optimized with response surface methodology using Box-Behnken design. The optimal extraction conditions were as follows: ultrasonic power, 440 W; liquid to material ratio, 7.0:1 mL/g; pH value of 6.0 at 54.5 ℃ for 10 min. Under these conditions, the extraction yield of phenolics achieved 1.816 ± 0.0187 mg gallic acid equivalents/gram FW. The free radical scavenging activity of ultrasonic-assisted enzymatic extraction extracts was determined by 1,1-diphenyl-2-picrylhydrazyl·assay with EC50 values of 0.25, and total antioxidant activity was determined by ferric reducing antioxidant power assay with ferric reducing antioxidant power value of 0.998 mmol FeSO4/g compared with the referential ascorbic acid of 1.184 mmol FeSO4/g.

Suscetibilidade à podridão negra e produtividade de brócolis em função de doses de nitrogênio e potássio

O objetivo do presente estudo foi investigar a influência da adubação com nitrogênio e com potássio na severidade da podridão negra e na produtividade de brócolis tipo inflorescência única. O delineamento utilizado foi em blocos casualizados, com 4 repetições, em esquema de parcelas subdivididas com fatorial nas subparcelas. Na parcela avaliou-se a influência da inoculação (plantas injuriadas com água destilada e inoculadas com Xanthomonas campestris pv. campestris) e na subparcela avaliou-se o fatorial 4 x 4 correspondendo a doses de potássio (0, 275, 550 e 825 kg ha-1) e de nitrogênio (0, 150, 300 e 450 kg ha-1). O brócolis híbrido BRO68 foi inoculado utilizando o método de palito aos 64 dias após a semeadura. Foi verificado que maiores doses de potássio aplicadas reduziram a severidade da doença, porém a ausência ou o excesso de nitrogênio aumentaram a severidade da doença. Estimou-se que as maiores produções de inflorescência de brócolis foram obtidas nas doses de 541 a 751 kg ha-1 de K2O e 286 a 328 kg ha-1 de N. No entanto, ao se considerar uma adubação equilibrada para obter maior produtividade, tamanho de inflorescência e maior resistência à podridão negra as doses indicadas são de 283 kg ha-1 de N e 550 kg ha-1 de K2O.

Dark-chilling of Seedlings Affects Initiation and Morphology of Broccoli Inflorescence

The constant supply of broccoli heads for a vegetable market can be kept by the differentiation of sowing time and the age of seedlings. Dark-chilling of young seedlings can also modify the time of transplanting, subsequent plant development, yield and inflorescence quality. The aim of the present study was to analyze the influence of seedling dark-chilling on the inflorescence initiation and the morphological quality of broccoli heads. The experiment was carried out at the University of Agriculture in Krakow (South Poland) in the years 2009 and 2010, with broccoli (Brassica oleracea L. var. italica Plenck) medium late cultivar ‘Monaco’ F1. The examined factors were the age of seedlings (4-, 6-, 8-, and 10-week-old) and dark-chilling (2°C/2 weeks and non-chilled control). Microscopic analysis of the apex sections was performed to determine the time of the inflorescence differentiation in chilled and non-chilled seedlings of different age. Chosen morphological features of the mature heads were also described as depended on age and chilling of seedlings. The inflorescence initiation was observed between 4 and 6 week of the plant ontogeny. Especially 4-week-old seedlings, chilled by two weeks, were more advanced in the generative development in comparison to non-chilled control. Low temperature applied in the seedling stage did not cause the head buttoning. Inflorescences developed by broccoli planted from 4 and 6-week-old seedlings, both chilled and control, were characterized by the best visual quality, determined by a convex head shape, tight branching angle, small and uniform size and regular form of flower buds. Chilling of oldest, 8- and 10-week-old seedlings negatively affected the inflorescence quality, through planed and spread shape of heads and non-uniform shape of flower buds.

Use of Dactylopius coccus Costa (Hemiptera: Coccoidea) Pigments in the Detection of Larvae and Pupae of Plutella xylostella (L.) (Lepidoptera: Yponomeutidae)

Carmines obtained from the dye of Dactylopius coccus Costa (Hemiptera: Coccoidea) were used for the detection of larvae and pupae of Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) in broccoli inflorescences. Larvae were dyed with carmine II and red cochineal, while the majority of the dyes, with the exception of carmine III and the aqueous extract, were suitable to dye pupae. In the broccoli lumps exposed to the dyes, only the verge of the stems were actually dyed, right in the position where the incision took place, an appropriate characteristic for implementing this technique for commercial use.

Stingless bees damage broccoli inflorescences when collecting fibers for nest building

The stingless bee Trigona spinipes (Fabricius, 1793) (Hymenoptera: Apidae) is an important pollinator for various crops, but constitutes an occasional pest of other plant species since it causes injury to leaves, stems, flowers and fruits while collecting nest materials. The aim of the present study was to determine the damage caused by T. spinipes to a broccoli (Brassica oleracea L. var. italica, Brassicaceae) growing on an organic farm. A significant number of plants (72.5 %) presented damaged inflorescences, while 39% of all of the inflorescences suffered some degree of injury. The activities of T. spinipes caused scarifications on the stems of the inflorescences, and these typically evolved to epidermal cicatrices up to 10 mm wide. In some cases, the lesions were sufficiently deep to cause partial destruction of the vascular tissues, and this lead to thinner (< 5 mm diameter) floral stems that may collapse. To the best of our knowledge, this is the first report concerning the attack of broccoli plants by T. spinipes. The results obtained should serve to highlight the possibility that stingless bees could be responsible for direct and/or indirect damage to vegetable crops, and to stimulate the development of control strategies for these incidental pests.

Broccoli yield in response to top-dressing fertilization with green manure and biofertilizer

The objective of this work was to evaluate the productive performance of broccoli under different top-dressing organic fertilizations. The experiment was conducted under protected cultivation, in a completely randomized design with four replications, with two plants per experimental unit. Broccoli seedlings were produced in a commercial substrate in styrofoam trays. The seedlings were transplanted to plastic pots containing 10.0 L of substrate made up of subsoil and organic compost at the ratio of 3:1 (v/v), respectively, which is equivalent to about 20.0 t ha-1 of organic compost at planting. After seedling establishment, the top-dressing fertilization treatments were applied: gliricidia biomass associated or not with liquid biofertilizer of cattle manure to the soil and bokashi. Two control treatments were established: one with mineral fertilization recommended for the crop and the other without top-dressing fertilization. The broccoli production was evaluated (commercial standard). Plants that received mineral fertilizer were more productive, however, they were not significantly different (p&gt;0.05), by Dunnet test, from the plants fertilized with 2.5 t ha-1 gliricidiabiomass (dry mass) associated with liquid biofertilizer (2.0 L m-2) applied to soil. Top-dressing fertilizations with only gliricidia, at 2.5 and 5.0 t ha-1 of biomass (dry mass), resulted in no significant increase in production of broccoli inflorescence. The use of bokashi in addition to gliricidia biomass and liquid biofertilizer reduced the efficiency of the fertilization compared with plants that received only gliricidia and liquid biofertilizer.

Seasonal Effects on Bioactive Compounds and Antioxidant Capacity of Six Economically Important Brassica Vegetables

Research on natural and bioactive compounds is increasingly focused on their effects on human health, but there are unexpectedly few studies evaluating the relationship between climate and natural antioxidants. The aim of this study was analyze the biological role of six different Brassica vegetables (Brassica oleracea L. and Brassica rapa L.) as a natural source of antioxidant compounds. The antioxidant activity may be assigned to high levels of L-ascorbic acid, total phenolics and total flavonoids of each sample. The climate seasons affected directly the concentration of bioactive components and the antioxidant activity. Broccoli inflorescences and Portuguese kale showed high antioxidant activity in Spring-Summer whilst turnip leaves did so in Summer-Winter. The Brassica vegetables can provide considerable amounts of bioactive compounds and thus may constitute an important natural source of dietary antioxidants.