Dry Basil Research Articles

Evaluation of drying techniques for postharvest residue utilization in 'Nufar' Basil (Ocimum basilicum L.) production

In this study, drying techniques including lyophilization, forced convection, marquee with polyshade, and refractive window were evaluated in the post-harvest residue of Nufar variety basil (Ocimum basilicum L.) in the department of Tolima, Colombia. The physicochemical and bromatological analysis showed that lyophilization and forced convection better maintained the organoleptic properties of dry basil, while the marquee with polyshade technique did not affect the phenolic content and antioxidant capacity. The refractive window technique showed higher rehydration capacity but lower essential oil content. In the sensory evaluation, the infusions of dried leaves in the marquee with polyshade method were highly accepted. The results suggest that drying by forced convection and marquee with polyshade are effective methods to preserve the quality of dried basil, presenting a viable alternative for the use of post-harvest residue and improving the useful life of the product, benefitting local producers by increased employability and added value.

Modeling and Optimization of Energy and Exergy Parameters of a Hybrid-Solar Dryer for Basil Leaf Drying Using RSM

This study deals with the optimization of energetic and exergetic parameters of a hybrid-solar dryer to dry basil leaves under determined experimental conditions at three air temperatures (40 °C, 55 °C, and 70 °C) and three bed thickness levels (2, 4, and 6 cm). The optimization of the thermodynamic parameters was performed using the response surface method (RSM) based on the central composite design (CCD) and the desirability function (DF) to maximize the drying rate, exergy efficiency, improvement potential rate and the sustainability index, and to minimize the energy utilization, energy utilization ratio and exergy loss rate. These parameters were calculated on the basis of the first and second laws of thermodynamics as the response variables. Based on the results obtained, it was determined that the optimal conditions for basil drying were at a drying air temperature of 63.8 °C and a bed thickness of 2 cm. At this point, the parameters of the drying rate, energy utilization, energy utilization ratio, exergy efficiency, exergy loss rate, improvement potential rate and sustainability index were obtained with the maximum utility function (D = 0.548) as 0.27, 0.019 (kJ/s), 0.23, 65.75%, 0.016 (kJ/s), 1.10 (kJ/s) and 0.015, respectively.

Essential oil and linalool contents in basil (Ocimum basilicum) irrigated with reclaimed water

Abstract Essential oils (EO) are volatile compounds with complex chemical compositions that are derived from the secondary metabolism of aromatic herbs. There are several applications of EO in the industrial and medical sectors. Basil (Ocimum sp.) is one of the most important EO-producing aromatic herbs. In this study, EO content (EOC) and linalool content (LC) in basil irrigated with reclaimed water were investigated. Plant development parameters, nutrient absorption and crude protein (CP) content were also evaluated. The experiment was conducted in a greenhouse, with five different treatments and five repetitions each. Compared with treatments only using water, the results of those with reclaimed water irrigation showed higher nutrient absorption, CP contents (in their foliar tissue), length of plant branches, foliar biomass weights, and EOC and LC. EOC reached up to 0.58% of the dry biomass and LC was up to 5.84% of EO mass. In practice, it is estimated that around 5.8 kg of EO and 0.34 kg of linalool can be obtained from one ton of dry basil biomass.

Square Wave Voltammetric (SWV) Determination of Quercetin in Tea Samples at a Single-Walled Carbon Nanotube (SWCNT) Modified Glassy Carbon Electrode (GCE)

The voltammetric determination of quercetin in tea samples was performed at a modified sensor which was fabricated by the addition of a single-walled carbon nanotube dispersion on a glassy carbon electrode. Due to the electrochemcal activity of quercetin, electroanalytical methods were used with great success for the determination of quercetin. The electrochemical properties of quercetin were investigated. Quercetin in water and methanol extracts of tea samples were determined at the modified glassy carbon electrode by using square wave voltammetry. The results were found to be 116.4 and 116.3 µg quercetin equivalent/g dry green tea, 127.9 and 104.24 µg quercetin equivalent/g dry basil tea 27.5 and 26.1 µg quercetin equivalent/g dry black tea. The limit of detection and limit of quantification values for quercetin for the 0.01 to 100 µM concentration range were 7.7 nM and 25.6 nM, respectively. Very low concentrations of quercetin were successfully determined by square wave voltammetry with sensitivity and selectivity.

Growth, yield, plant quality and nutrition of basil (Ocimum basilicum L.) under soilless agricultural systems

Traditional agricultural systems are challenged by globally declining resources resulting from climate change and growing population. Alternative agricultural practices such as aquaponics (includes crop plant and aquatic species) and hydroponics (includes crop plant only) have the potential to generate high yield per unit area using limited land, water, and no soil. A soilless agricultural study was conducted at the Georgia Southern University, Statesboro, GA, USA from August to November, 2015. The growth, yield, quality, and nutrition of basil (Ocimum basilicum L.) cultivar Aroma 2, were compared between aquaponic and hydroponic systems using crayfish (Procambarus spp.) as the aquatic species. Non-circulating floating raft systems were designed using 95L polyethylene tanks. Equal amounts of start-up fertilizer dose were applied to both systems. The objective was to understand how the additional nutritional dynamics associated with crayfish influence the basil crop. Both fresh and dry basil plant weights were collected after harvest, followed by leaf nutrient analysis. Leaf chlorophyll content, water pH, nitrogen and temperature were measured periodically. Aquaponic basil (AqB) showed 14%, 56%, and 65% more height, fresh weight, and dry weight, respectively, compared to hydroponic basil (HyB). It is logical to assume that crayfish waste (excreta and unconsumed feed) has supplied the additional nutrients to AqB, resulting in greater growth and yield. The chlorophyll content (plant quality) or leaf nutrients, however, did not differ between AqB and HyB. Further research is needed to investigate aquaponic crayfish yield, overall nutritional dynamics, cost-benefit ratio, and other plant characteristics under soilless systems.

DESIGN, CONSTRUCTION AND PERFORMANCE EVALUATION OF A SOLAR DRYING UNIT OF BASIL LEAVES

Two similar solar drying units were designed, constructed and evaluated for drying basil leaves (Ocimum basilicum L.) as a medicinal and aromatic plant at initial moisture content of 590.73% (d.b) or 85.52% (w.b) under Fayoum conditions by using heated air. Each drying unit consists of a flat-plate solar collector, which oriented and tilted with an optimum tilt angle and attached with drying chamber. The drying experiments were carried out to examine the effect of basil leaves thicknesses (2, 4 and 6 cm) and airflow rate (0.015 and 0.025 m3.sec-1) on the basil leaves drying rate. The obtained results indicated that the daily average total solar radiation flux incident on the tilted solar collector surface (29.30 MJ. m-2.day-1) was greater than that incident on the horizontal surface (24.30 MJ.m-2.day-1) by 24.58%. The output higher air temperatures were obtained at the lower airflow rate whereas; the energy gained to the air from the solar collector was relatively higher at the higher airflow rate as compared with the lower airflow rate. Consequently, the solar collector with the higher airflow rate increased the overall thermal efficiency by 5.46% as compared to the lower airflow rate. The moisture content of dried basil leaves was strongly affected by the basil leaves thickness and the airflow rate. The final moisture content of dried basil leaves ranged from (11.52% to 14.58% d.b) depending on the drying temperature cycle. Very small changes were observed in the colour and shape of heated-air dried basil leaves as compared to that dried at direct sun rays. The essential oil contents of dried basil leaves were slightly higher for the drying unit with the higher airflow rate as compared with the corresponding values obtained from the drying unit with the lower airflow at all basil leaves thicknesses. While on Contrast, total chlorophylls contents were slightly higher for the drying unit with the lower airflow rate as compared with the corresponding values obtained from the drying unit with the higher airflow at all basil leaves thicknesses. Effect of the individual variables (airflow rate, basil leaves thickness, moisture removed, and their interactions) on the drying rate was statistically analyzed. Under the conditions of this study, the optimum depth to dry basil leaves by using heated air is 4 cm.

Mineral composition of different basil (Ocimum spp.) genotypes

This experiment investigated mineral composition of 13 basil genotypes (Ocimum spp.) in order to find varieties supporting human dietary intake of essential minerals and to evaluate basil genotypes which could serve for herbal production as raw material in pharmaceutical or food processing industry. In addition, this study tested a potential risk of the accumulation of heavy metals during the commercial production of basil on agricultural soil. Mineral composition of basil genotypes was found to be in association with its genetic potential, where some of them can be used in human nutrition as an additional source of several minerals, particularly micronutrients (Fe, Mn, Zn), which generally improve human immune system. Iron-rich basil genotypes were identified in this experiment, like Compact (3576.0 mg/kg), with Lattuga (1585.6 mg/kg) and Blue spice (1167.9 mg/kg) genotypes, containing more than 1000 mg/kg of Fe in herbal part on dry basil (d.m.). This attract a special attention as a source of iron, especially for humans with low Fe intake, and consequently, for people with low level of hemoglobin. Basil grown on agricultural soil was tested on the accumulation of heavy metals (Cu, Co, Cu, Ni, Cr, Pb), which were not found to be excessive in herbal parts of the plants. Cluster analysis (CA) distinguished Ocmium spp. genotypes in two separate groups. Despite of significant differences among the genotypes, content of Fe, Mn, Co, Cr, Ni and Pb made a clear distinction between the clusters.

Modeling of Basil Leaves Drying by GA–ANN

Abstract In this research, the experiment is done by a dryer. It could provide any desired drying air temperature between 20 and 120°C and air relative humidity between 5 and 95% and air velocity between 0.1 and 5.0 m/s with high accuracy, and the drying experiment was conducted at five air temperatures of 40, 50, 60, 70 and 80°C and at three relative humidity 20, 40 and 60% and air velocity of 1.5, 2 and 2.5 m/s to dry Basil leaves. Then with developed Program in MATLAB software and by Genetic Algorithm could find the best Feed-Forward Neural Network (FFNN) structure to model the moisture content of dried Basil in each condition; anyway the result of best network by GA had only one hidden layer with 11 neurons. This network could predict moisture content of dried basil leaves with correlation coefficient of 0.99.

Linalool and methyl chavicol present basil (Ocimum sp.) cultivated in Brazil

In Brazil, Ocimum species are commonly known as aromatic and restorative herbs. The present research aimed to study the chemical composition of the essential oils of fresh and dry basil (Ocimum sp) leaves obtained by hydrodistillation and analyzed by GC-FID and GC-MS. The obtained yield was 0.70% for dry leaves and 0.26% for fresh leaves. The major compounds were: linalool (29.50-32.26%) and methyl chavicol (36.81-41.62%). Eucalyptol could also be detected (9.99-7.68%). The oil from dry leaves presented a more complex chemical composition. This study serves to contribute to the knowledge of medicinal plants occurring in Brazil.

Determinação de óleos essenciais de alfavaca (Ocimum gratissimum L.), orégano (Origanum vulgare L.) e tomilho (Thymus vulgaris L.)

O presente trabalho teve como objetivo a caracterização de plantas frescas e secas (comerciais) de alfavaca, orégano e tomilho, a obtenção dos óleos essenciais através do método de arraste a vapor e a quantificação dos compostos químicos por CG/EM. As plantas frescas e as secas comerciais foram submetidas às análises de umidade, extrato etéreo, proteína, fibra bruta, cinzas, extrato não nitrogenado, valor calórico, teor de óleo essencial e identificação dos compostos majoritários através da cromatografia gasosa-espectrometria de massas. Dentre a caracterização obtida os resultados na base seca mostraram-se promissores, sendo o teor de proteína e de cinzas na alfavaca seca comercial com 17,34 g 100 g-1 e 8,12 g 100 g-1, respectivamente; a fibra bruta no orégano seco comercial com 15,65 g 100 g-1; o extrato etéreo, o extrato não nitrogenado e o valor calórico no tomilho seco comercial com 9,30 g 100 g-1, 52,72 g 100 g-1 e 356,74 Kcal 100 g-1, respectivamente. Obteve-se o maior rendimento de óleo essencial na alfavaca seca comercial com 1,02%, enquanto a alfavaca fresca apresentou o menor rendimento, com apenas 0,13%. Na alfavaca fresca encontrou-se 87,38% de eugenol e 6,27% de timol, enquanto na alfavaca seca comercial observou-se redução no eugenol (71,12%) e aumento do timol (13,28%). No orégano fresco foram quantificados quatro picos o γ-terpineno (33,45%), 4-terpineol (25,59%), timol (14,21%) e carvacrol (2,30%). Já no óleo essencial de orégano seco comercial houve redução no γ-terpineno (28,73%) e aumento no 4-terpineol (27,58%), timol (19,71%) e carvacrol (3,67%). No óleo essencial do tomilho fresco foram quantificados três picos o borneol (66,66%), timol (13,41%) e linalol (3,24%). Por outro lado, no óleo essencial do tomilho seco comercial houve redução no borneol (37,90%) e aumento no timol (20,61%) e linalol (10,34%). Pode-se concluir que as folhas secas comerciais analisadas de alfavaca, orégano, e tomilho apresentam potencial para o enriquecimento dos alimentos ou para a obtenção dos óleos essenciais.

香気成分と組織構造の比較解析による乾燥スィートバジルの品質評価

香気成分と組織構造の比較解析による乾燥スィートバジルの品質評価

Quantification of Iprodione in Dry Basil Using Silica Gel Supported Titanium Dioxide

Iprodione is an agricultural fungicide that is difficult to detect in foods by HPLC because it coelutes with natural compounds in the food. We previously showed that food matrix could be degraded with titanium dioxide powder (TP). Here we describe an improved method for detection of iprodione using silica gel supported titanium dioxide (SGT). To synthesize SGT, titania-sol was mixed with diethanolamine, 2-propanol, and titanium tetraisopropoxide. After titania-sol was infiltrated into the silica gel (particle diameter 4 mm), the mixture was dried and then heated. Crude basil extract containing iprodione was mixed with SGT in a quartz vial, and the vial was irradiated with a UV light to selectively decompose the matrix interfering with the iprodione determination. In HPLC chromatograms of the treated solution, the interference peak decreased 35 times faster with SGT than with TP. When SGT (11 g) was added to the extract (20 mL) of dry basil (2 g), black light irradiation for 30 min was enough to quantify iprodione. The recovery rate of iprodione was 99.1%. Thus, the photocatalytic cleanup method using SGT is effective for analyzing residual iprodione in dry basil.

A Clean-up Method by Photocatalysis for HPLC Analysis of Iprodione in Dry Basil

Titanium dioxide was used as a photocatalyst to decompose interfering substances for a quantitative analysis of a fungicide (iprodione) in dry basil by HPLC. A quartz vial containing basil extract and titanium dioxide was irradiated with black light. The interfering substances were almost completely decomposed by 180 min of irradiation, whereas 88.3% of iprodione remained. The recovery of iprodione was 102.6% by the proposed method in basil extracts. This may have been due to different decomposition rates of the analyte and interfering substances.

The potential of some spice essential oils in the control of A. parasiticus CFR 223 and aflatoxin production

Essential oils of sweet basil ( Ocimum basilicum), cassia ( Cinnamomum cassia), coriander ( Coriandrum sativum) and bay leaf ( Laurus nobilis) at 1–5% (v/v) concentration in palm kernel broth inoculated with spore suspension (10 6/ml) of Aspergillus parasiticus CFR 223 were evaluated for their potential in the control of aflatoxigenic fungus A. parasiticus CFR 223 and aflatoxin production. Healthy sorghum grains (120/treatment) immersed in the oils and distributed in three petri dishes with wet cotton wool were also inoculated with spore suspension (10 6/ml) of A. parasiticus CFR 223 and assayed for grain protection. Sweet basil oil at optimal protective dosage of 5% (v/v) was fungistatic on A. parasiticus CFR 223 and aflatoxins produced in vitro and on fungal development on sorghum grains ( P ⩽ 0.05) with a residual effect that lasted for 32 days. In contrast, oils of cassia and bay leaf stimulated the mycelia growth of the fungus in vitro but reduced the aflatoxin concentration (B 1 + G 1) of the fungus by 97.92% and 55.21% respectively, while coriander oil did not have any effect on both the mycelia growth and aflatoxin content of the fungus. The combination of cassia and sweet basil oils at half their optimal protective dosages (2.5% v/v) completely inhibited the growth of the fungus. The feasibility of implementing the results of this study to control aflatoxins was examined by the addition of whole and ground dry basil leaves at 5% and 10% (w/w), respectively, to 10 g sorghum, groundnut, maize and melon seed after 35 days storage period. It was found that the addition of whole and ground basil leaves markedly reduced aflatoxin contamination; however, 10% (w/w) of whole leaves was more effective as the reduction in aflatoxin was between 89.05% and 91%. The findings showed that aflatoxins can be controlled by co-storing whole sweet basil leaves with aflatoxin infected foods. The economic value of the study lies in the simplified technique for control of aflatoxin contamination in agricultural products and the benefits derivable from the use of local resources.

EFFECT OF ORGANIC AND SYNTHETIC MULCHES ON YIELD OF BASIL UNDER DRIP IRRIGATION

Small-scale herb growers in the U.S. Virgin Islands traditionally water their crops with sprinkler cans and garden hoses. This method is inefficient and consumes large amounts of water, a scarce resource in the islands. Introduction of drip irrigation has reduced water use in vegetable production. Integrating this system with mulches may further cut water use, making herb production more profitable. Basil (Ocimum basilicum) was grown in plots with organic (compost or straw) and synthetic (black plastic or weed barrier) mulches. A no mulch control plot was also included. All plots were drip irrigated to maintain soil moisture at -30 kPa. Total plant fresh weight and leaf fresh and dry weights were highest in the compost mulch treatment. Fresh and dry basil yields in black plastic mulched plots were almost identical with those in compost mulch, but did not differ from other treatments. Black plastic mulch reduced water use 46% compared with 27% for compost or straw mulch. All mulch treatments resulted in increased water use efficiency. Organic mulches reduced surface soil temperature, while synthetic mulches increased soil temperature 2-5°C.