Citrus Limettioides Research Articles

Analyses of sweet lime essential oils (Citrus limettioides Tan) in relation to various planting sites in Egypt

Analyses of sweet lime essential oils (Citrus limettioides Tan) in relation to various planting sites in Egypt

Generation of analytical food composition data for traditionally consumed fruits and vegetables in Costa Rica

The objective of this research was to generate food composition data for fruits and vegetables of traditional consumption in Costa Rica. The sampling plan was carried out considering seasonality, producing areas, commercialization, and cultivar. The number of primary samples (n) was determined using Cochran’s formula with a coefficient of variation of 12% and a maximum estimated error (r) of 5% for the content of vitamin C in fruits and vegetables. The samples were collected in wholesale markets of Costa Rica. Eleven foods were analyzed in the form that they are usually consumed. A determination of mass (g), size (cm), and edible fraction, was made, and the following nutrients were analyzed (in triplicate): protein, fat, fatty acid profile, carbohydrates, dietary fiber, content of minerals (Na, Ca, K, P, Fe, Cu, Zn, Mg, Se), fat-soluble and water-soluble vitamins. The analyzed foods were Cas (Costa Rican guava, Psidium friedrichsthalianum), Granadilla (Passiflora ligularis), Jocote (Spondias purpurea), Sweet lime (Citrus limettioides), Water apple (Syzygium malaccense), Cashew (Anacardium occidentale), Passion fruit (Passiflora edulis), Peach palm (Bactris gasipaes) and Tacaco (Sechium tacaco). Tacaco is endemic to Costa Rica. Most of these fruits and vegetables provide significant amounts of fiber, some minerals, and vitamins, especially vitamin C.

Molecular characterization of divergent isolates of Citrus bent leaf viroid (CBLVd) from citrus cultivars of Punjab, Pakistan.

Citrus viroid infection is emerging as a serious threat because of its efficient systemic movement within the host plant and its quick spread due to contaminated pruning tools. A survey was conducted to investigate the primary distribution and molecular characterization of Citrus bent leaf viroid (CBLVd) and its variants in different citrus cultivars. A total of 154 symptomatic citrus samples were collected and detected by RT‒PCR with newly designed specific primers with the incidence of 36.33%. During biological indexing study on Etrog citron, expressions of reduced leaf size, yellowing with a light green pattern, and bending were observed. Amplified products were sequenced and analyzed using a nucleotide BLAST search, which showed 98% homology with other CBLVd isolates. The results of the phylogenetic tree analysis showed the presence of two main groups (A and B), with the predominant variants of CBLVd, i.e., CVd-I-LSS (Citrus viroid Low Sequence Similarity) sequences, clustering in subgroup A1 along with newly detected CVd-I-LSS from Palestinian sweet lime (Citrus limettioides), which has been identified as a new host of CVd-I-LSS in Pakistan. Further analysis of the sequences in subgroup A1 showed that the variant of CVd-I-LSS infecting citrus cultivars had a close relationship with isolates reported from China, Japan, and Iran, which may have resulted from the exchange of planting material. This study also unveiled the variability in nucleotide sequences of CBLVd, which made it unable to be detected by old primers. The results of this study indicate that the widespread presence of divergent variants of CBLVd is a major concern for the citrus industry in Pakistan and other countries where virulent isolates of CBLVd are prevalent. These findings suggest the need for future research on effective management and quarantine measures to stop the spread of CBLVd.

Creating optimal nutrient conditions in soil and plants during the flower induction process of sweet lime (Citrus limettioides) under calcareous soil conditions to increase the yield

A study was conducted on 6-year-old sweet lime trees on the Mexican lime (Citrus aurantifolia Swingle) rootstock in a randomized complete block design with ten treatments and three replications in southern Fars to determine the appropriate time of plant supplementary feeding to increase flower production and the yield in calcareous soils. In 2016 and 2017, 40 trees that had the same planting and growing conditions, were selected to determine the flower induction time. Ten times (22nd of October, 1st, 11th, and 20th November, December, and January), four branches that had a length of 120 cm and a diameter of half a centimeter were selected on each tree in four geographical directions. At each time, the branches of three trees were ringed at a distance of 120 cm from the tip of the branch, and all the leaves were removed. At the time of flower emergence, the number of flowers was counted. The results showed that the flower induction in these trees was in early December. Based on the results of this experiment and previous research in this field, in September 2017, the 7-year-old trees grafted on the Mexican lime rootstock were treated with the foliar application of nitrogen as urea [CO(NH2)2] and zinc as zinc sulfate (ZnSO4) at three concentrations including 0, 3, and 5 g∙L–1, alone and by combination in two separate pieces in a randomized complete-block factorial design including nine treatments and three replications to increase the yield using elements involved in the flowering. At the harvest time, fruit juice, TSS, TA, vitamin C, average fruit weight, and single tree yield were measured. According to the results, the combination of urea and zinc sulfate at a concentration of 5 g∙L–1 led to an increase in the average fruit weight (58 g) and the yield (68 kg) compared to the control.

Larvicidal effect of the Citrus limettioides peel essential oil on Aedes aegypti

Citrus limettioides (Rutaceae), popularly known as “sweet lime” or “sweet lemon”, is rich in essential oil. Citrus sp. essential oils present a wide spectrum of biological activities, including insecticidal and larvicidal. In this sense, we aimed to investigate the larvicidal potential of Citrus limettioides peel essential oil on the main urban vector of dengue, chikungunya, yellow fever, and Zika viruses Aedes aegypti. The chemical characterization of the material revealed a monoterpene-rich essential oil (mainly limonene – 48.28% – and linalool – 32.17%). The C. limettioides peel essential oil presented a good larvicidal activity on A. aegypti (LC50 = 18.14 µg mL−1). Moreover, the compounds linalyl acetate and isopropyl tiglate, identified in the investigated essential oil, presented a predicted insecticide activity on A. aegypti. Finally, the safety of the C. limettioides peel essential oil was demonstrated on RAW 264.7 murine macrophages. These results support the idea of using the C. limettioides peel essential oil to the development of an economically viable larvicidal product.

Genetic Characterization of Tunisian Lime Genotypes Using Pomological Traits

Abstract Citrus genus includes a wide number of species that have been long cultivated and well adapted in Tunisia. It is represented by small number of plantations and considered as underutilized in Tunisia. Our goal was to genetically characterize Tunisian lime genotypes to obtain data useful for gene conservation and breeding purposes. The survey of genotypes was conducted in the Cap Bon region, where citrus cultivation is the most spread. Sixteen quantitative and 19 qualitative parameters were evaluated. The observed accessions belonged to three different species: Citrus limetta, Citrus latifolia (limes Byrsa), and Citrus limettioides (limes of Palestine) according to Tanaka classification. Principal component analysis confirmed these classifications. Four-cell analysis (FCA) was used to determine the most threatened genotypes. Quantitative traits were evaluated and allowed the discrimination between genotypes. Many quantitative traits of fruit and juice were highly positively and significantly correlated. Phenotypic diversity was determined using Shannon–Wiener diversity index (H’). The highest value of diversity index was observed for both vesicle thickness and thickness of segment walls (H’ = 0.98). Intermediate values were observed for both fruit axis (H’= 0.49) and pulp firmness (H’ = 0.43). However, fruit shape (H’ = 0.24), shape of fruit apex (H’ = 0.24), and vesicle length (H’ = 0.33) presented the lowest values of diversity index. Current findings will be useful to conserve threatened genotypes ex situ and on farm and also will guide strategic conservation on Citrus genetic resources for future breeding programs.

Removal of Cadmium(II) from Water using Modified Citrus limettioides Peels: Thermodynamic and Isotherm Studies

The adsorption performance of sulphuric acid treated low cost adsorbent synthesized by using Citrus limettioides peel as an effective raw material for the removal of cadmium(II) from water. The batch adsorption method was carried out to optimize some parameters like contact time, pH and adsorbent dose. The nonlinear isotherm equations were used to calculate the different isotherm constant of five isotherm models namely Freundlich, Langmuir, Dubinin-Radushkevich, Redlich-Peterson and Sips. The Langmuir monolayer adsorption capacity of chemically modified Citrus limettioides peel was found to be 287.60 mg g-1. The negative values of ΔGº and ΔHº showed that the adsorption process is spontaneous and exothermic.

Apparent Tolerance to Huanglongbing in Citrus and Citrus-related Germplasm

In a Fort Pierce, FL, field planting, plant growth, and Huanglongbing (HLB) severity were assessed as indicators of HLB tolerance on progenies of 83 seed-source accessions of Citrus and Citrus relatives mainly from the Riverside, CA, genebank. The HLB-associated pathogen [Candidatus Liberibacter asiaticus (CLas)] and vector [asian citrus psyllid (ACP), Diaphorina citri] were abundant, and trees were naturally challenged for 6 years before metrics (leaf mottle, percent canopy mottle, overall health, canopy density, canopy width, canopy height, and trunk diameter) were collected in Oct. and Nov. 2015. The healthiest trees with low or no HLB symptoms were distant citrus relatives: Balsamocitrus dawei, Bergera koenigii, Casimiroa edulis, Clausena excavata, Murraya paniculata, and one accession of Severinia buxifolia. Within Citrus, most of the healthiest trees with densest canopies, little leaf loss, and greater growth were those with pedigrees that included Citrus medica (citron). These included progenies of Citrus hybrid (‘Limon Real’), Citrus limetta, Citrus limettioides, Citrus limonia, C. medica, Citrus volkameriana, and some Citrus limon accessions. Trees in this category exhibited distinct leaf-mottle characteristic of HLB and substantial pathogen titers, but maintained dense canopies and exhibited good growth. Trees from seed-source accessions in the genus Citrus without citron in their background were generally among the least healthy overall with less dense canopies. The exceptions were progenies of two Citrus aurantium accessions, which were markedly healthier than progenies of other Citrus seed-source accessions not derived from citron. Linear regression analysis, between metrics collected and pedigree of seed parent, indicated that percentage of citron in the pedigree significantly correlated with measures of tolerance. Although no commercial Citrus genotypes yielded progenies with strong HLB resistance, in this field experiment several progenies maintained dense canopies and good growth, and may be useful for breeding HLB tolerant cultivars.

Lead(II) removal from aqueous solution using Citrus limettioides peel and its modified form: isotherms, kinetics and thermodynamic studies

The Pb(II) adsorption capacity of carbon derived from Citrus limettioides peel (CLPC), which is a novel waste material, was evaluated regarding the contact time, pH and adsorbent dose during batch adsorption processes with raw C.limettioides peel (CLP). The optimal contact time for the adsorption of Pb(II) ions onto the peel and peel carbon was 3 h, and the optimal pH ranged from 4.0 to 5.0 for CLP and 4.0–6.0 for CLPC, respectively. The equilibrium data fit well with Langmuir isotherm, indicating that the Pb(II) ions formed a homogenous monolayer on the adsorbent surface. Maximum monolayer adsorption capacity of Pb(II) ions on peel (CLP) and peel carbon (CLPC) was found to be 125.00 and 166.67 mg g−1, respectively. The kinetic studies showed that the adsorption data followed a pseudo-second-order kinetic model. The surface morphology and functionality of the CLP and CLPC were characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy and FT-IR. Various thermodynamic parameters, including the standard Gibbs free energy (∆G°), standard enthalpy (∆H°) and standard entropy (∆S°), were evaluated. The CLP and CLPC were tested with Pb(II) plating wastewater through a batch mode process over five cycles; CLPC showed better results than CLP.

Kinetic, mechanism and equilibrium studies on removal of Pb(II) using Citrus limettioides peel and seed carbon

The sorption behaviour of Pb(II) ions onto activated carbon prepared from Citrus limettioides peel (CLPC) and seed (CLSC), which is a novel waste material, was evaluated as a function of contact time, pH, adsorbent dose, ionic strength, initial metal ion concentration and temperature in batch adsorption processes with raw Citrus limettioides peel (CLP) and seed (CLS). The maximum uptake of lead(II) ions was obtained at pH range 4.0–6.0 for CLPC, CLSC and 5.0–6.0 for raw materials (CLP, CLS). The optimal contact time was found to be 3 h. Surface morphology and functionality of the adsorbent were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis and Fourier-transform infrared (FT-IR) spectroscopy. The equilibrium data fit well with the Langmuir isotherm, confirming monolayer coverage of lead(II) ions onto CLP, CLPC, CLS and CLSC. The Langmuir monolayer adsorption capacity of CLP, CLPC, CLS and CLSC was found to be 123.60, 166.67, 15.32 and 142.86 mg/g. The calculated thermodynamic parameters showed that the sorption process was feasible, spontaneous and exothermic in nature. Kinetic studies demonstrated that adsorption of lead(II) ions followed a pseudo-second-order equation, suggesting that the adsorption process is presumably chemisorption. The adsorbents were tested for removal of Pb(II) from electroplating wastewater in connection with the reuse and selectivity of the adsorbents.

Isotherm, kinetic, and thermodynamic studies on Ni(II) removal from aqueous solution by Citrus limettioides seed and its carbon derivative

Activated carbon was prepared from Citrus limettioides seed (CLSC), a novel waste material by chemical modification with sulfuric acid was applied for the adsorption Ni(II) from aqueous solutions. The effect of contact time, pH, adsorbent dose, initial metal ion concentration, and temperature were studied in batch experiments. According to the experimental results, the equilibrium time, optimum pH range, and adsorbent dosage were found to be 3 h, pH = 4.0–8.0 and 1 g L−1, respectively. In addition, raw Citrus limettioides seeds (CLS) were used as adsorbents at the same parameters. Ni(II) removal for CLSC and CLS were obtained 99.00% and 37.00% in turn. The equilibrium data agreed well with Langmuir model, which confirmed the monolayer coverage of Ni(II) ions onto CLS and CLSC. The Langmuir monolayer adsorption capacity of the CLSC was found to be 36.06 mg g−1 which was significantly about 3.5 times greater than that of CLS (10.23 mg g−1) at 300 K. The kinetic data followed pseudo‐second order model and intra‐particle diffusion was not the sole rate‐controlling factor. Surface morphology and structural analysis of CLSC prior to and after adsorption were characterized by SEM and EDX. The presence of hydroxyl, carboxylic, and sulfonic acid groups are confirmed by FTIR spectra. The adsorbents were also tested for the removal of Ni(II) from electroplating wastewater in connection with the reuse and selectivity of the adsorbents. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1384–1395, 2015

Removal of nickel(II) from aqueous solution using Citrus Limettioides peel and seed carbon

The agricultural wastes like Citrus Limettioides peel and seed to be suitable precursor for the preparation of carbon [Citrus Limettioides peel carbon (CLPC) and seed carbon (CLSC)] has been explored in the present work, utilizing sulfuric acid as the activating agent. Adsorption studies were performed by varying contact time, solution pH, adsorbent dose and temperature. The equilibrium time for Ni(II) ions was determined as 4h and optimal pH was 4–7. Surface morphology and functionality of the CLPC and CLSC were characterized by SEM, EDX and FT-IR. The experimental data were analysed using the Freundlich, Langmuir, Temkin, Redlich–Peterson, Sips and Dubinin–Radushkevich adsorption isotherm equations using nonlinear regression analysis. Equilibrium data were found to fit well in the Langmuir isotherm, which confirmed the monolayer coverage of Ni(II) ions. The Langmuir monolayer adsorption capacity of CLPC and CLSC was found to be 38.46 and 35.54mg/g. The thermodynamic parameters indicated that the adsorption process was spontaneous and exothermic in nature. The kinetic data followed pseudo-second order model with film diffusion process. The adsorbents were tested with Ni(II) plating wastewater in connection with the reuse and selectivity of the adsorbents.

Nickel (II) removal using modified Citrus limettioides peel

The Ni(II) adsorption capacity of carbon derived from Citrus limettioides peel (CLP), which is a novel waste material (CLPC), was evaluated regarding contact time, pH and adsorbent dose during batch adsorption processes with raw CLP. The optimal contact time for the adsorption of Ni(II) ions onto the peel and peel carbon was 3 h, and the optimal pH ranged from 5.0 to 8.0 for CLP and 4.0–8.0 for CLPC, respectively. The removal percentage decreased from 85.0 to 70.0 % for CLP and remained nearly constant (99 %) for CLPC when the initial Ni(II) concentration was increased from 10 to 50 mg L−1. The equilibrium data fit the Langmuir isotherm with a high R 2 value, indicating that the Ni(II) ions formed a homogenous monolayer on the adsorbent surface. Adsorption capacity of Ni(II) ions on peel (CLP) and peel carbon (CLPC) was found to be 25.64 and 38.46 mg g−1, respectively. The surface morphology and functionality of the CLP and CLPC before and after adsorption were characterized using SEM, EDX and FT-IR. Various thermodynamic parameters, including the standard Gibbs free energy (∆G°), standard enthalpy (∆H°) and standard entropy (∆S°), were evaluated. The CLP and CLPC were tested with Ni(II) plating wastewater through a batch-mode process over five cycles; CLPC showed better results than CLP.

Essential oil composition and antimicrobial activity of Citrus limittioides Tanaka cultivated in Iran

This study was led with the purpose of evaluating the antimicrobial activity and identifies the essential oil composition of Citrus limettioides Tanaka cultivated in Iran. Essential oil was obtained by hydro-distillation using Clevenger type apparatus during approximately 3 hours and analyzed using gas chromatography/mass spectrometry (GC/ MS). Forty-seven components were identified in Citrus limettiuides Tanakaessential oil that represented 99.99% of the oil. The main components of the oil were Limonene (39.22%), Linalool (18.54%), nDecane (9.55%), (E)-Nerolidol (5.11%), (E)-β-Ocimene (3.13%). Antibacterial activity of essential oil of C. limettiuides Tanaka performed by disc diffusion method. Result showed that the oil of Citrus limettiuides Tanakahas has good antimicrobial activity against Staphylococcus aureus, Candida albicans and Escherchia coli, three medically important pathogens.

Prediction of citrus canker epidemics generated through different inoculation methods

Citrus canker epidemics were generated with 108 cfu/ml of Xanthomonas axonopodis pv. citri (ex Hasse) on Citrus limonia cv. China lemon, Citrus reticulate cv. kinnow, Citrus jambhiri, Citrus reticulate cv. Feutral’s early and Citrus limettioides using four inoculation techniques. Natural inoculum was also relied upon for infection. Overall, the injection infiltration method led to maximum disease generation followed by spray, pinprick and smear inoculation methods. Citrus canker incidence along with environmental data were recorded and subjected to stepwise regression analysis. Except relative humidity, the relationship of weekly air temperature (maximum and minimum), rainfall and wind speed with citrus canker disease development in all citrus cultivars was positively correlated and best explained by linear regression. Overall, two environmental variable model containing maximum and minimum air temperature fit the data well explaining 93% variability in disease development. The observed citrus canker incidence values and those predicted by the model were close in most of citrus cultivars. This two environmental variable model can be used to issue advance warning forecasts for the timely management of the citrus canker in Pakistan.

Chemical composition of volatile oil from Citrus limettioides and their inhibition of colon cancer cell proliferation

Volatile oil from Palestine sweet lime (PSL) was analyzed for their chemical constituents. A total of 24 compounds were identified in hydro-distilled oil by GC–MS with electron impact mode using Zebron (ZB)-5 and ZB wax columns. The PSL volatile oil included 13 monoterpenes, 9 sesquiterpenes, one acyclic ester and one straight chain hydrocarbon. Four compounds namely d-limonene, myrcene, citronellal and β-citronellol were further confirmed by NMR spectral analysis. In vitro treatment of PSL volatile oil exhibited dose dependent inhibition of colon cancer (SW480) cell proliferation. Induction of apoptosis by the PSL volatile oil was confirmed through Annexin V staining indicating translocation of phosphatidylserine from inner to outer leaflet of plasma membrane, upon incubation of cells with volatile oil at 50μg/mL. Treatment with PSL volatile oil suppressed the expression of both Cox-2 and IL-6 suggested the potential inhibition of inflammation and activation of apoptosis in human SW480 colon cancer cells. Suppression of Cox-2 and IL-6 expression in the cells treated with PSL volatile oil were significant compared to treatment with d-limonene (50ppm), one of the major constituent of citrus volatile oils. This is the first report on chemoprofiling and anti-proliferative activities of volatile oil from PSL.

Analysis of genetic relationship between ‘Bakraee’ (Citrus sp.) and some known Citrus genotypes through SSR and PCR-RFLP markers

Phylogenic relationships and genetic diversity in citrus are considered to be important in clarifying their genetic relationships, germplasm characterization and the registration of new varieties. The ‘Bakraee’ (Citrus sp.) is an unknown natural biotype which is being used widely as rootstock as well as edible fruit in some regions of Iran. In the present research work, phylogenic relationships among ‘Bakraee’ and some commercially important citrus varieties were investigated through SSR and PCR-RFLP molecular markers. Two UPGMA dendrograms were generated using SSR and PCR-RFLP data. SSR data showed 0.87 and 0.65 genetic similarities between ‘Bakraee’ and rough lemon (Citrus jambhiri Lush.) and sweet lime (Citrus limettioides Tan.), respectively. PCR-RFLP analysis demonstrated that all of the amplified fragments in ‘Bakraee’ are also present in rough lemon. Our study confirmed a close relationship between ‘Bakraee’ and rough lemon and support the possibility of rough lemon as maternal parent in the hybrid origin of ‘Bakraee’.

Chemical Composition and Antimicrobial Activity of Essential Oil of Citrus limettioides Tanaka

Aim: The present study is aimed to isolate the essential oil of Citrus limettioides and analyze its chemical composition and antimicrobial potential. Methods: The essential oil (EO) isolated by hydro-distillation from the peel of fully matured ripen fruits of Citrus limettioides Tanaka and analysed by Gas Chromatography-Mass Spectrometry (GC-MS). The antifungal activity in terms of zone of inhibition and minimum inhibitory concentration (MIC) of the essential oil was tested against ten food borne fungal strains and ten bacterial strains. The EO was also examined for any possible toxicity or adverse effect resulting from its consumption. Results: Fourteen different components were identified constituting approximately ≥99% of the oil. The major components were dl-limonene (89.089%), β-myrcene (2.933%), (±)-linalool (2.927%), α-pinene (0.865%), (E)-citral (0.749%) etc. According to disc diffusion assay and broth micro-dilution method showed that EO has a wide spectrum of antimicrobial activity against the tested strains with their MIC ranging from 3.12 μl/ml to50 μl/ml. Conclusion: It can be concluded that EO of Citrus limettioides can be used in skincare formulations for acne control, in treatment of various infectious diseases like typhoid fever, food poisoning, inflammation, sepsis, endocarditis, bladder, prostate and epididymal infections. Along with this it can also be used as safer and alternative means of food preservation. No serious or life-threatening side effects were observed on the haematological and biochemical parameters of mice fed with specific dose of EO of Citrus limettioides, therefore the EO can be recommended as safe fumigant for preservation of food commodities.

Anatomical studies of stems, roots and leaves of selected citrus rootstock varieties in relation to their vigour

The present studies were carried out to consolidate information on anatomical features of stem, root and leaves from different vigour groups of citrus rootstock varieties. Troyer citrange (Citrus sinensis × Poncirus trifoliata), rough lemon (Citrus jambhiri), swingle citrumelo (Citrus paradisi × P. trifoliata), sweet lime (Citrus limettioides), carrizo citrange (C. sinensis × Poncirus trifoliata), sour orange (Citrus aurantium) and flying dragon (P. trifoliata) were examined to investigate relationships between their internal structure and vigour. It was found that vigorous rootstock, rough lemon (C. jambhiri) possessed lower proportions of bark (phloem) in the stems and roots as well as larger vessel elements in the xylem, when compared with least vigorous rootstocks, flying dragon (P. trifoliata). Smaller but more vessel elements were found in stem cross-sections than root cross-sections of three month’s old rootstock seedlings. The possible mechanism of vascular differentiation induced by young leaf primordia, following the original polarity and developing toward the roots is discussed. Key words: Citrus rootstock, anatomical features, stem, root, leaves.

Volatile Constituents of Peel and Leaf Oils from Citrus limettioides Tan.

The chemical composition of the volatile compounds of peel and leaf oils from Citrus limettioides Tan. cultivated in Yucatan Peninsula was studied by GC and GC-MS. Sixty and sixty-six compounds were identified in the peel and leaf oils, respectively. The chemical components of these oils showed marked differences in chemical composition. The most prominent compound in the peel oil was limonene (73.2 %), while in the leaf oil the major components were limonene (32.1 %), citronellal (21.7 %) and linalool (15.5 %).