Kenaf Leaf Research Articles

Physicochemical, nutritional, and sensory characteristics of gluten‐free muffins prepared from finger millet, germinated black soybean, and kenaf leaves composite flour

The study aims to develop gluten free muffins using finger millet flour (FMF), germinated black soybean flour (GBSF) and kenaf leaf powder (KLP) at varying concentrations (100:0:0, 70:26:4, 50:46:4, 30:66:4, 0:96:4). Significant (p≤0.05) improvement in functional properties of composite flour was observed with the increased incorporation levels of GBSF and KLP while a reverse trend was found for pasting properties. The physical parameters namely height, diameter and specific volume of composite flour muffins were significantly (p≤0.05) lower than the control muffin (100% refined wheat flour). Further, FMF based muffins were dark in color and showed harder and gummier texture. The sensory appraisal revealed that the variant (70:26:4) of FMF based muffins received sensory scores comparable to control muffin. The protein, fat, crude fiber, ash, mineral content, total phenolic content, total flavonoid content, and antioxidant activity of composite flour muffin was significantly (p≤0.05) higher as compared to control muffin. The Scanning electron microscopy (SEM) analysis revealed that microstructure of composite flour muffin was denser with reduced number of air cells as compared to well-developed structure of control muffin.

PHYTOCHEMICAL ASSAY AND ANTIOXIDANT ACTIVITY AGAINST DPPH OF ETHANOL EXTRACT FROM KENAF LEAF (Hibiscus cannabinus L.)

Kenaf (Hibiscus cannabinus L.) is an environmentally friendly natural fiber-producing plant that can produce diversified products, such as paper, wallcover, car interior, geotextile, soil safer, fiber drain, particle board, and plastic reinforcement as well as biofuel industry raw materials. Kenaf plant is a plant that has been only part of the fibers of the stem alone so that many unprofitable side products such as kenaf leaves after harvesting only as a waste. In Africa the leaves of kenaf are widely used as medicine This study aims to analyze phytochemical compounds and study the antioxidant activity of the kenaf leaf. The study started by doing phytochemical test and analyzing antioxidant in kenaf leaf and then testing its antioxidant activity with DPPH method. The results showed that the leaves of kenaf contain secondary metabolites of phytochemical compounds such as flavonoids, alkaloids, steroids, saponins, carbohydrates and tannins and have antioxidant activity that is quite good that is 44.4813 ppm.

Molecular characterization of Hollyhock leaf curl virus and associated DNA-satellites infecting Malva parviflora in Pakistan

Leaf samples from Malva parviflora plants exhibiting vein yellowing and chlorosis were collected during 2013–14 from Lahore, Pakistan and analysed for the presence of begomovirus and associated DNA satellites through PCR and subsequent sequencing. The identified full-length begomovirus genome shared maximum nucleotide (nt) sequence identity at 92.5% with Hollyhock leaf curl virus (HoLCV), representing a new strain, which was tentatively designated as HoLCV-Mal. The betasatellite shared maximum nt sequence identity (92.8%) with Kenaf leaf curl betasatellite (KLCuB) and represents a new isolate of KLCuB. The two identified alphasatellites were 86% identical to each other and shared maximum nt sequence identities at 94.3 and 93.2% with Ageratum conyzoides symptomless alphasatellite (ACSLA) and Ageratum yellow vein India alphasatellite (AYVIA), respectively. Thus, these are the new isolates of ACSLA and AYVIA identified from M. parviflora in Pakistan. To the best of our knowledge, this is the first report of a complete monopartite begomovirus complex from M. parviflora in Pakistan.

Association of Kenaf leaf curl betasatellite with Mesta yellow vein mosaic virus in naturally infected Malvastrum coromandelianum

Weeds host viruses and, therefore, may act as virus reservoirs for cultivated plants. Malvastrum coromandelianum is a widespread non-cultivated species that exhibits yellow vein disease symptoms suggestive of a begomovirus infection. A monopartite begomovirus (isolate 40SB), associated with a betasatellite (33SA), was identified in Malvastrum coromandelianum. The isolate 40SB showed maximum of 95.2% identity with Mesta yellow vein mosaic virus (MeYVMV). Whereas, 33SA was classified as a member of Kenaf leaf curl betasatellite (KLCuB) by sharing maximum 86.3% nucleotide identity with isolates of this DNA satellite. Although trans-replication and patho-symptomatology of the disease complex are yet to be verified biologically, this is the first report of a natural association of KLCuB with MeYVMV.

Kenaf (Hibiscus cannabinus L.) Impact on Post-Germination Seedling Growth

<p>The chemical interaction between plants, which is referred to as allelopathy, may result in the inhibition of plant growth and development. The objective of this research was to determine the impact of kenaf (<em>Hibiscus cannabinus</em> L.) plant extracts on the post-germination growth of five plant species. Four concentrations (0, 16.7, 33.3 and 66.7 g/L) of kenaf bark, core, and leaf extracts were applied to the germinated seeds of redroot pigweed (<em>Amaranthus retroflexus</em> L.), green bean (<em>Phaseolus vulgaris</em> L.), tomato (<em>Solanum lycopersicum </em>Mill.), cucumber (<em>Cucumis sativus</em> L.), and Italian ryegrass (<em>Lolium multiflorum</em> Lam.). After 7 days, the developing seedlings were measured to determine the length of their hypocotyls (mm) and radicles (mm), and the number of hair roots. Tomato, Italian ryegrass, and redroot pigweed followed similar negative trends in their responses to the extract source (kenaf bark, core, and leaves) and the impact of extract concentration, whereas, cucumber had a mixed response and green bean reacted positively to the kenaf extracts. Tomato was the most sensitive species tested across all kenaf extracts and concentrations, resulting in decreased hypocotyl, radicle, and root growth. Green bean exhibited no negative effects due to the kenaf extracts, but actually produced increased hypocotyl growth as a result of the kenaf bark, core, and leaf extracts. The kenaf extracts resulted in a mixed response for cucumber. The kenaf leaf and bark extract decreased cucumber radicle growth, whereas, the bark and core extracts increased hypocotyl growth. Italian ryegrass hypocotyl growth decreased across all extract sources (bark, core, and leaf), while the leaf extract also reduced root growth. All kenaf extracts reduced redroot pigweed radicle growth, while the core and leaf extracts reduced hypocotyl growth. The research demonstrated that kenaf leaf extracts were the most allelopathic and the hypocotyls were the most sensitive. Future research should isolate the chemicals responsible for both the negative and positive allelopathic impact on the various plant species, determine if the extracts will influence more mature plants, and pursue cultural practices to utilize these natural allelopathic materials to benefit crop production and limit weed competition.</p>

Impact of Kenaf (Hibiscus cannabinus L.) Leaf, Bark, and Core Extracts on Germination of Five Plant Species

The chemical interaction between plants, which is referred to as allelopathy, may result in the inhibition of plant growth and development. The objective of this research was to determine the impact of kenaf (Hibiscus cannabinus L.) plant extracts on the seed germination of five plant species. Four concentrations (0, 16.7, 33.3 and 66.7 g/L) of kenaf leaf, bark, and core extracts were applied to the germination medium of redroot pigweed (Amaranthus retroflexus L.), green bean (Phaseolus vulgaris L.), tomato (Solanum lycopersicum Mill.), cucumber (Cucumis sativus L.), and Italian ryegrass (Lolium multiflorum Lam.) seeds. The treated seeds were placed in a non-illuminated incubator at 27 oC. Germination was recorded after 7 days in the incubator. Seed germination decreased with increasing extract concentration for all the plant species tested, except for green bean. Tomato, cucumber, Italian ryegrass, and redroot pigweed followed similar trends in their responses to the extract source (kenaf bark, core, and leaves) and the impact of extract concentration. The research demonstrated that kenaf leaf extracts were allelopathic by reducing seed germination for tomato, cucumber, Italian ryegrass and redroot pigweed. Sensitivity to the allelopathic impact of the kenaf leaf extracts from highest to lowest was Italian ryegrass > tomato > redroot pigweed > cucumber > green bean, with reductions in percentage germination of 79% (Italian ryegrass), 78% (tomato), 53% (redroot pigweed), 40% (cucumber), and 0% (green bean). Future research should pursue cultural practices to utilize these natural allelopathic materials to benefit crop production and limit weed competition, assess the impact of kenaf extracts on post-germination growth, and isolate the active ingredients in the kenaf leaf extracts that are allelopathic.

Optimization of Two-Dimensional Gel Electrophoresis for Kenaf Leaf Proteins

Abstract To establish a suitable and effective protocol of protein extraction for two-dimensional gel electrophoresis (2-DE) analysis in kenaf leaf tissues, three extraction methods (trichloroacetic acid/acetone, urea/thiourea, and phenol extraction methods) were applied to the extraction of kenaf leaf protein. The results were compared in regard to protein extraction efficiency, sodiumdodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and 2-DE gels. Furthermore, the 2-DE system was optimized for four aspects: the pH range of IPG (immobilized pH gradient) stripes, sampling methods, sample volumes, and concentration of polyacrylamide gels. The data presented showed that the phenol extraction method is the best method to perform 2-DE analysis of kenaf leaf protein. The protein extracted from phenol extraction method reached the purity of (26.40±0.859)%, showed (25.67±1.53) protein bands in one dimension SDS-PAGE gels, and (1 374±54.44) protein spots on 2-DE gels. The research also indicates that kenaf leaf protein spots were distributed mainly within the pH range of 4-8. More clear background with a better distribution effect and many protein spots could be obtained on 2-DE gels under the conditions of active rehydration loading, 24 cm IPG strips (linear pH gradient of 4-7), 1.4 mg samples, and 12% SDS-PAGE gels.

Changes in flavonoid content and tyrosinase inhibitory activity in kenaf leaf extract after far-infrared treatment

The tyrosinase inhibitory activity of ethanolic extract of kenaf (Hibiscus cannabinus L.) leaf was evaluated before and after subjecting it to far-infrared (FIR) irradiation. The main component of the extract was analyzed as kaempferitrin (kaempferol-3,7-O-α-dirhamnoside). Prior to FIR irradiation, no inhibitory activity of the extract was detected in a tyrosinase assay. However, after FIR irradiation for 1h at 60°C, significant tyrosinase inhibitory activity (IC(50)=3500 ppm) was observed in it. In HPLC analysis, derhamnosylation products (kaempferol, afzelin, and α-rhamnoisorobin) were detected. The inhibitory activity may be due to the existence of derhamnosylation products. This study demonstrated that FIR irradiation can be used as a convenient tool for deglycosylation of flavonoid glycoside.

Biological and molecular variability of the begomoviruses associated with leaf curl disease of Kenaf in India.

SUMMARY Kenaf (Hibiscus cannabinus L.) is a malvaceous bast fibre crop and the most promising source of “tree-free” newsprint in the world. For the last few years a begomovirus associated leaf curl disease of kenaf, characterized by upward leaf curling and stunted growth, has been observed at different locations in India. In this study biological and molecular analyses of kenaf leaf curl disease-associated begomovirus isolates collected from three different locations were carried out. Whitefly transmission efficiency was different for the three geographical isolates which possessed very narrow host ranges. Except kenaf, the isolates from northern India could not infect other experimental hosts studied. Cloning and sequencing of the complete genomes of these isolates revealed the presence of three different monopartite begomoviruses. In eastern and southern India Mesta yellow vein mosaic virus (MeYVMV) and Tomato leaf curl Joydebpur virus (ToLCJV) were associated with the disease, respectively, while in northern India a new begomovirus species was involved, tentatively named Kenaf leaf curl virus (KLCuV). Nucleic acid spot hybridization tests using non-radiolabeled probes developed against these viruses detected the presence of begomoviruses from symptomatic samples collected from the fields at the different locations.

Hibiscus chlorotic ringspot virus upregulates plant sulfite oxidase transcripts and increases sulfate levels in kenaf (Hibiscus cannabinus L.)

Hibiscus chlorotic ringspot virus (HCRSV) coat protein (CP) is required for encapsidation and virus systemic movement. To better understand the roles of HCRSV CP in virus infection and its interactions with host proteins, a cDNA library of kenaf (Hibiscus cannabinus L.) was constructed and screened by using a yeast two-hybrid system (YTHS) to identify CP-interacting proteins. One protein identified was sulfite oxidase (SO) and the interaction was confirmed in vitro and in vivo. The interaction was found to be associated with peroxisomes by immunofluorescent labelling of peroxisomes by an anti-SKL signal peptide antibody. Our YTHS results showed that only the P and S domains of CP interacted with SO from kenaf. This is probably due to the exposure of these two domains on the outer surface of the capsid. Peroxisomes were observed to aggregate in HCRSV-infected cells, and biochemical assays of total protein from kenaf leaf extracts showed that SO activity and SO-dependent H(2)O(2)-generating activity in the HCRSV-infected leaves increased compared with that in mock-inoculated kenaf plants.

Development of a kenaf (Hibiscus cannabinus L.) protoplast system for a replication study of Hibiscus chlorotic ringspot virus

A protoplast isolation protocol was developed for kenaf (Hibiscuscannabinus L.) leaf tissue from potted plants. The kenaf protoplast system was further established to support replication of Hibiscus chlorotic ringspot virus (HCRSV). Kenaf protoplasts were isolated using 0.8% cellulase and 0.5% macerase digestion for 16 h at 25°C. Average yields ranged from 2×105 to 1×106 protoplasts g–1 fresh leaves. After polyethylene glycol-mediated transfection with in vitro transcripts of HCRSV full-length cDNA clone p223, time-course analysis showed synthesis of a genomic RNA and two sub-genomic RNAs 1 and 2 in the protoplasts. The optimal RNA concentration for the infection assay was 4 µg per 4×105 protoplasts. Western blot showed the presence of a coat protein synthesized 72 h post transfection. This kenaf protoplast system serves as a tool for in vivo studies of replication processes of HCRSV.