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GC-MS Analysis of Bioactive Compounds in Ethanolic Leaf Extract of Hellenia speciosa (J.Koenig) S.R. Dutta

R R

Appl Biochem Biotechnol, 2022 Jan;194(1):176-186.
PMID: 34762268 DOI: 10.1007/s12010-021-03742-2

Hellenia speciosa (J.Koenig) S.R. Dutta is a plant species belonging to the family Costaceae. It is widely distributed in China, India, Malaysia, Indonesia, tropical, and subtropical Asia. In Ayurveda, the rhizome of this plant has been extensively used to treat fever, rash, asthma, bronchitis, and intestinal worms. The objective of the present study was to investigate the phytochemical constituents of the leaf of Hellenia speciosa using gas chromatography and mass spectroscopy analysis (GC-MS). The GC-MS analysis revealed the presence of 17 phytochemical components in the ethanolic leaf extract of Hellenia speciosa. The prevailing bioactive compounds present in Hellenia speciosa were thymol (RT-10.019; 3.59%), caryophyllene (RT-11.854; 0.62%), caryophyllene oxide (RT-13.919; 1.34%), artumerone (RT-14.795; 1.35%), hexadecanoic acid methyl ester (RT-17.536; 2.77%), 9,12-octadecanoic acid methyl ester (RT-19.163; 1.35%), squalene (RT-24.980; 1.19%), piperine (RT-25.745; 3.11%), beta tocopherol (RT-26.681; 2.88%), vitamin E (RT-27.290; 2.64%), progesterone (RT-29.608; 3.18%), caparratriene (RT-29.861; 9.72%), and testosterone (RT-30.73; 5.81%). The compounds were identified by comparing their retention time and peak area with that of the literature and by interpretation of mass spectra. The results and findings of the present study suggest that the plant leaf can be used as a valuable source in the field of herbal drug discovery. The presence of bioactive compounds justifies the use of plant leaves for treating various diseases with fewer side effects and recommended the plant of pharmaceutical importance. However, further studies are needed to undertake its bioactivity and toxicity profile.

Matched MeSH terms: Plant Leaves/chemistry*
Two new phloroglucinol derivatives and five photosensitizing pheophorbides from Syzygium polyanthum leaves (Salam)

Har LW, Shaari K, Boon LH, Kamarulzaman FA, Ismail IS

Nat Prod Commun, 2012 Aug;7(8):1033-6.
PMID: 22978223

Two new phloroglucinol derivatives, identified as anthuminoate (1) and anthuminone (2), were isolated from the ichthyotoxic ethyl acetate fraction of Syzygium polyanthum leaves. In addition, bioassay-guided fractionation followed by dereplication of the photocytotoxic fraction of this plant part has resulted in the identification of five known pheophorbides as the bioactive constituents. The compounds were identified as pheophorbide-a, methyl pheophorbide-a, methyl hydroxypheophorbide-a, pheophorbide-b and hydroxypheophorbide-b. Inhibition of cell viability shown by the compounds ranged from 83.3 to 86.1% at a test concentration of 5 microg/mL. This shows that Syzygium polyanthum leaves are a potential new source in the studies of photocytotoxicity for photodynamic therapy.

Matched MeSH terms: Plant Leaves/chemistry*
Quantitative and physical evaluation of patchouli essential oils obtained from different sources of Pogostemon cablin

Hussin N, Mondello L, Costa R, Dugo P, Yusoff NI, Yarmo MA, et al.

Nat Prod Commun, 2012 Jul;7(7):927-30.
PMID: 22908584

Patchouli essential oil can be obtained from fresh, dried and fermented plant material. It is a highly valuable product in the fragrance industry and its quality changes depending upon raw material age and oil storage. In this work, patchouli essential oils derived from different treatments have been subjected to GC-FID quantitative analysis using an internal standard (ISTD) method with response factors (RF). Samples were obtained from i) fresh plants; ii) hydrodistillation of one year mature and fermented plants; iii) hydrodistillation of one year mature plants; iv) commercial products from Indonesia and Malaysia. Linear Retention Indices (LRI) for both polar and non-polar GC-MS analyses were also measured as a tool for qualitative analysis towards a homologous series of C7-C30 n-alkanes. The results obtained confirmed that, in all samples, patchouli alcohol was the main volatile constituent, with higher amount in lab-scale produced oils, compared with commercial samples. Other major compounds, in lab oils and commercial samples respectively, were: delta-guaiene, alpha-guaiene, pogostol, seychellene and alpha-patchoulene. Another 36 compounds were also found.

Matched MeSH terms: Plant Leaves/chemistry
A new carbazole alkaloid from the leaves of Malayan Murraya koenigii

Sim KM, Teh HM

J Asian Nat Prod Res, 2011 Oct;13(10):972-5.
PMID: 21972815 DOI: 10.1080/10286020.2011.602970

New carbazole alkaloid, 7-hydroxymurrayazolinine (1), was isolated from the ethanol extract of the leaves of Malayan Murraya koenigii, together with five known carbazole alkaloids, mahanimbine (2), bicyclomahanimbine (3), girinimbine (4), koenimbine (5), and murrayamine-D (6). Their structures were elucidated on the basis of spectroscopic analysis.

Matched MeSH terms: Plant Leaves/chemistry
Fulltext Variability and performance evaluation of introgressed Nigerian dura x Deli dura oil palm progenies

Noh A, Rafii MY, Mohd Din A, Kushairi A, Norziha A, Rajanaidu N, et al.

Genet. Mol. Res., 2014;13(2):2426-37.
PMID: 24781997 DOI: 10.4238/2014.April.3.15

Twelve introgressed oil palm (Elaeis guineensis) progenies of Nigerian dura x Deli dura were evaluated for bunch yield, yield attributes, bunch quality components and vegetative characters at the Malaysian Palm Oil Board Research Station, in Keratong, Pahang, Malaysia. Analysis of variance revealed significant to highly significant genotypic differences, indicating sufficient genetic variability among the progenies for bunch yield and its attributes, vegetative characters and bunch quality components, except fruit to bunch ratio. Fresh fruit bunch yield ranged from 167 kg·palm(-1)·year(-1) in PK1330 to 212 kg·palm(-1)·year(-1) in PK1351, with a mean yield of 192 kg·palm(-1)·year(-1). Among the progeny, PK1313 had the highest oil to bunch ratio (19.36%), due to its high mesocarp to fruit ratio, fruit to bunch ratio and low shell to fruit ratio. Among the progenies, PK1313 produced the highest oil yield of 31.4 kg·palm(-1)·year(-1), due to a high mesocarp to fruit ratio (61.2%) and a low shell to fruit ratio (30.7%), coupled with high fruit to bunch ratio (65.6%). PK1330 was found promising for selection, as it had desirable vegetative characters, including smaller petiole cross section (27.15 cm2), short rachis length (4.83 m), short palm height (1.85 m), and the lowest leaf number (164.6), as these vegetative characters are prerequisites for selecting palms for high density planting and high yield per hectare. The genetic variability among the progenies was found to be high, indicating ample scope for further breeding, followed by selection.

Matched MeSH terms: Plant Leaves/growth & development*
Chemotaxonomical markers in essential oil of Murraya koenigii

Nagappan T, Ramasamy P, Vairappan CS

Nat Prod Commun, 2012 Oct;7(10):1375-8.
PMID: 23157015

The composition of the essential oils of Murraya koenigii (L.) Spreng, cultivated at six locations in Peninsula Malaysia and Borneo are presented. The oils were obtained from fresh leaves by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS); 61 compounds were identified, of which eleven were present in all the specimens analyzed. The two major volatile metabolites were identified as beta-caryophyllene (16.6-26.6%) and alpha-humulene (15.2-26.7%) along with nine minor compounds identified as beta-elemene (0.3-1.3%), aromadendrene (0.5-1.5%), beta-selinene (3.8-6.5%), spathulenol (0.6-2.7%), caryophyllene oxide (0.7-3.6%), viridiflorol (1.5-5.5%), 2-naphthalenemethanol (0.7-4.8%), trivertal (0.1-1.0%) and juniper camphor (2.6-8.3%). The results suggest that beta-caryophyllene and alpha-humulene could be used as chemotaxonomical markers for Malaysian M. koenigii, hence these specimens could be of the same stock and different from the ones in India, Thailand and China.

Matched MeSH terms: Plant Leaves/chemistry
Species diversity in the Palaeotropical leaf-litter genus Apelaunothrips (Thysanoptera, Phlaeothripinae)

Mound LA

Zootaxa, 2013;3741:181-93.
PMID: 25112982 DOI: 10.11646/zootaxa.3741.1.7

Species of Apelaunothrips are fungus-feeders on dead leaves, particularly in leaf-litter, and they are recorded across the Old World tropics from Africa to northern Australia and southern Japan. All species in this genus have the maxillary stylets 4-6 microns in diameter, considerably broader than the 2-3 micron diameter that is typical among Phlaeothripinae. The species are largely uniform in structure, but in four species the larger males have fore femora enlarged with a conspicuous tubercle on the inner margin at the base. In one of these species, the males are dimorphic, with no intermediates between large and small individuals, in contrast to the continuous variation in structure found in many polymorphic Phlaeothripidae. A key is provided to the 37 recognised species of Apelaunothrips, including the following: A. desleyae sp.n. from northern Australia; A. bogor sp.n. from Java; A. gombak sp.n. from Peninsular Malaysia.

Matched MeSH terms: Plant Leaves/parasitology
Dunaliine A, a new amino diketone from Desmos dunalii (Annonaceae)

Awang K, Abdullah Z, Mukhtar MR, Litaudon M, Jaafar FM, Hadi AH, et al.

Nat Prod Res, 2009;23(7):652-8.
PMID: 19401920 DOI: 10.1080/14786410802323743

Dunaliine A (1), a new amino diketone, has been isolated from the leaves of Desmos dunalii together with four known dihydrochalcones: 2',4-dihydroxy-4',6'-dimethoxy-3',5'-dimethyldihydrochalcone (2), 2',4-dihydroxy-4',6'-dimethoxydihydrochalcone (3), 2',4-dihydroxy-4',5',6'-trimethoxydihydrochalcone (4) and 2',4-dihydroxy-5'-methyl-4',6'-dimethoxydihydrochalcone (5). The structures of these compounds were established notably by spectral analysis (1D- and 2D- (1)H, (13)C NMR), UV, IR and HRMS.

Matched MeSH terms: Plant Leaves/chemistry*
Leaf herbivory and decomposability in a Malaysian tropical rain forest

Kurokawa H, Nakashizuka T

Ecology, 2008 Sep;89(9):2645-56.
PMID: 18831185

There is accumulating evidence that similar suites of plant traits may affect leaf palatability and leaf litter decomposability. However, the possible association between leaf herbivory and litter decomposition rates across species in species-diverse natural ecosystems such as tropical rain forests remains unexplored, despite its importance in estimating the herbivory effects on carbon and nutrient cycling of ecosystems. We found no strong association between leaf herbivory and litter decomposition rates across 40 tree species in a Malaysian tropical rain forest, even though the leaf and litter traits were tightly correlated. This is because the leaf and litter traits related to herbivory and decomposition rates in the field were inconsistent. Leaf toughness accounted for only a small part of the variation in the herbivory rate, whereas a number of litter traits (the leaf mass per area, lignin to nitrogen ratio, and condensed tannin concentration) accurately predicted the decomposition rate across species. These results suggest that herbivory rate across species may not be strongly related to single leaf traits, probably because plant-herbivore interactions in tropical rain forests are highly diverse; on the other hand, plant-decomposer interactions are less specific and can be governed by litter chemicals. We also investigated two factors, phylogeny and tree functional types, that could affect the relationship between herbivory and decomposition across species. Phylogenetic relatedness among the species did not affect the relationship between herbivory and decomposition. In contrast, when the plants were segregated according to their leaf emergence pattern, we found a significant positive relationship between herbivory and decomposition rates for continuous-leafing species. In these species, the condensed tannin to N ratios in leaves and litter were related to herbivory and decomposition rates, respectively. However, we did not observe a similar trend for synchronous-leafing species. These results suggest that the relationship between herbivory and decomposition may be more greatly affected by functional types than by phylogenetic relatedness among species. In conclusion, our results suggest that well-defended leaves are not necessarily less decomposable litter in a tropical rain forest community, implying that herbivory may not generate positive feedback for carbon and nutrient cycling in this type of ecosystem.

Matched MeSH terms: Plant Leaves/metabolism*
Fulltext In vitro total phenolics, flavonoids contents and antioxidant activity of essential oil, various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah

Hossain MA, Shah MD, Gnanaraj C, Iqbal M

Asian Pac J Trop Med, 2011 Sep;4(9):717-21.
PMID: 21967695 DOI: 10.1016/S1995-7645(11)60180-6

OBJECTIVE: To detect the in vitro total phenolics, flavonoids contents and antioxidant activity of essential oil, various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.
METHODS: The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane, ethyl acetate, chloroform, butanol and aqueous methanol. The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane, ethyl acetate, chloroform, butanol and aqueous ethanol were determined by Folin - Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity using α, α-diphenyl- β-picrylhydrazyl (DPPH) method.
RESULTS: The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract (386.22 mg/g) followed by ethyl acetate (190.89 mg/g), chloroform (175.89 mg/g), hexane (173.44 mg/g), and butanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil. The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract > ethyl acetate extract >chloroform> butanol > hexane extract also the antioxidant activity was not detected in essential oil.
CONCLUSIONS: The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract. Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant.

Matched MeSH terms: Plant Leaves/chemistry
Distinctive phyllosphere bacterial communities in tropical trees

Kim M, Singh D, Lai-Hoe A, Go R, Abdul Rahim R, Ainuddin AN, et al.

Microb Ecol, 2012 Apr;63(3):674-81.
PMID: 21990015 DOI: 10.1007/s00248-011-9953-1

Recent work has suggested that in temperate and subtropical trees, leaf surface bacterial communities are distinctive to each individual tree species and dominated by Alpha- and Gammaproteobacteria. In order to understand how general this pattern is, we studied the phyllosphere bacterial community on leaves of six species of tropical trees at a rainforest arboretum in Malaysia. This represents the first detailed study of 'true' tropical lowland tree phyllosphere communities. Leaf surface DNA was extracted and pyrosequenced targeting the V1-V3 region of 16S rRNA gene. As was previously found in temperate and subtropical trees, each tree species had a distinctive bacterial community on its leaves, clustering separately from other tree species in an ordination analysis. Bacterial communities in the phyllosphere were unique to plant leaves in that very few operational taxonomic units (0.5%) co-occurred in the surrounding soil environment. A novel and distinctive aspect of tropical phyllosphere communities is that Acidobacteria were one of the most abundant phyla across all samples (on average, 17%), a pattern not previously recognized. Sequences belonging to Acidobacteria were classified into subgroups 1-6 among known 24 subdivisions, and subgroup 1 (84%) was the most abundant group, followed by subgroup 3 (15%). The high abundance of Acidobacteria on leaves of tropical trees indicates that there is a strong relationship between host plants and Acidobacteria in tropical rain forest, which needs to be investigated further. The similarity of phyllosphere bacterial communities amongst the tree species sampled shows a significant tendency to follow host plant phylogeny, with more similar communities on more closely related hosts.

Matched MeSH terms: Plant Leaves/microbiology*
Fulltext Enhancement of leaf gas exchange and primary metabolites under carbon dioxide enrichment up-regulates the production of secondary metabolites in Labisia pumila seedlings

Ibrahim MH, Jaafar HZ

Molecules, 2011 May 04;16(5):3761-77.
PMID: 21544039 DOI: 10.3390/molecules16053761

A split plot 3 by 3 experiment was designed to investigate and distinguish the relationships among production of primary metabolites (soluble sugar and starch), secondary metabolites (total phenolics, TP; total flavonoids, TF) and leaf gas exchange of three varieties of the Malaysian medicinal herb Labisia pumila Blume, namely the varieties alata, pumila and lanceolata, under three levels of CO₂ enrichment (400, 800 and 1,200 µmol mol⁻¹) for 15 weeks. The treatment effects were solely contributed by CO₂ enrichment levels; no varietal differences were observed. As CO₂ levels increased from 400 to 1,200 µmol mol⁻¹, the production of carbohydrates also increased steadily, especially for starch more than soluble sugar (sucrose). TF and TP content, simultaneously, reached their peaks under 1,200 µmol exposure, followed by 800 and 400 µmol mol⁻¹. Net photosynthesis (A) and quantum efficiency of photosystem II (f(v)/f(m)) were also enhanced as CO₂ increased from 400 to 1,200 µmol mol⁻¹. Leaf gas exchange characteristics displayed a significant positive relationship with the production of secondary metabolites and carbohydrate contents. The increase in production of TP and TFs were manifested by high C/N ratio and low protein content in L. pumila seedlings, and accompanied by reduction in cholorophyll content that exhibited very significant negative relationships with total soluble sugar, starch and total non structural carbohydrate.

Matched MeSH terms: Plant Leaves/metabolism*
Fulltext Acute oral toxicity and brine shrimp lethality of Elaeis guineensis Jacq., (oil palm leaf) methanol extract

Syahmi AR, Vijayarathna S, Sasidharan S, Latha LY, Kwan YP, Lau YL, et al.

Molecules, 2010 Nov 10;15(11):8111-21.
PMID: 21072022 DOI: 10.3390/molecules15118111

Elaeis guineensis (Arecaceae) is widely used in West African traditional medicine for treating various ailments. An evaluation on the toxicity of extracts of this plant is crucial to support the therapeutic claims. The acute oral toxicity and brine shrimp lethality of a methanolic extract of this plant was tested. Oral administration of crude extract at the highest dose of 5,000 mg/kg resulted in no mortalities or evidence of adverse effects, implying that E. guineensis is nontoxic. Normal behavioral pattern, clinical signs and histology of vital organs confirm this evidence. The E. guineensis extracts screened for toxicity against brine shrimp had 50% lethal concentration (LC₅₀) values of more than 1.0 mg/mL (9.00 and 3.87 mg/mL, at 6 and 24 h, respectively), confirming that the extract was not toxic. Maximum mortalities occurred at 100 mg/mL concentration while the least mortalities happened to be at 0.195 mg/mL concentration. The results of both tests confirm that E. guineensis is nontoxic and hence safe for commercial utilization.

Matched MeSH terms: Plant Leaves/chemistry*
[The roots of Cha and Gambir]

Sugiyama S

Yakushigaku Zasshi, 2005;40(2):98-106.
PMID: 17152831

This article attempts to trace the origin of tea. The author believes the ancient Chinese tea, "chia", is either Jicha (water extract from the pith of Acacia catechu that grows naturally in the mountainous border between the Yunnan province of China and southern Asian countries) or Jicha-Kagikazura (water extract from the young branches and leaves of Uncaris gambir, originally found in India/Sri Lanka). Both were pulverized after being kiln-dried and then mixed with water to produce a thick suspension, or tea. Although the drink is bitter and has an astringent property, it has a particular flavor with a refreshing after-taste. Its components with medicinal properties include tannin, catechin, and various flavonoids, making us believe it was worthwhile for the people at the time to consume the drink regularly. Generally speaking, tea cultivation in China flourished south of the Yangzi Jiang River including the present Zhejiang and Anhui provinces. Depending on the regions, there were words for tea in various languages, including the names of places where particular teas were grown. In addition to the names that appear in the famous Chajing book, it is interesting to note Da Fang pronounced tea as "TAH". Because the area south of the Yangzi Jiang has traditionally been active in foreign trade since the ancient and middle ages. People in this region consumed various foreign originated teas as well. This included Gambir, which was introduced to southern Asia (including present Malaysia and Indonesia) and was consumed as an herbal tea under names such as Guo Luo or Ju Luo teas. Paan, from India, also uses Gambir paste and was a popular chewing refreshment to prevent diseases caused by miasma as well as to keep one's mouth clean. The name A-sen-yaku used in Japan was taken from the plant name Acasia, and Gambir was used to dye Buddhist monks' Ke-Ra bags to a blackish yellow color. The Daikanwa dictionary states the Ra in the name, which means thin silk, was later replaced with "A". The official name for Ji-cha [Er Cha] in modern China is "Gaiji-cha", [Hal-Er Cha], which comes from the name of a variety of tea made by the Ai-Ni tribal subgroup of the ethnic Ha-Ni in Yunnan province. The [see character in text] character is pronounced "ni", which is a homophony of [character in text]. Based on these facts, "Ai-Ni" should be considered the same as "Hai-Ni". Because the ethnic groups in Yunnan province used primitive and tough tea leaves, which were eaten instead of being infused in water, the leaves were first fermented by being buried in the ground. Even today, people of these ethnic groups prefer fungus-fermented black tea with a particular flavor. In contrast, the ethnic Hans used and still use improved and softer young shoots of tea leaves to prepare mainly green tea. It has recently been discovered that Acapsia, as well as Gambir, has anti-oxidant properties, and that consumption over time is effective against many lifestyle-related adult diseases. It may be well worthwhile to cast fresh light upon ancient tea drinking customs.

Matched MeSH terms: Plant Leaves*
Fulltext Daily feeding of fresh Neem leaves (Azadirachta indica) for worm control in sheep

Chandrawathani P, Chang KW, Nurulaini R, Waller PJ, Adnan M, Zaini CM, et al.

Trop Biomed, 2006 Jun;23(1):23-30.
PMID: 17041548 MyJurnal

This study was conducted to evaluate the anthelmintic effect of neem (Azadirachta indica) on nematode parasites of sheep. Twelve Santa Ines cross bred sheep from a government farm were randomly selected and equally divided into control (n = 6) and treated groups (n =6). Faecal egg counts (FEC) using the modified McMaster technique and the FAMACHA score for assessing clinical anaemia were carried out daily and recorded for 6 weeks. At the end of the study all the animals were slaughtered and the total worm count (TWC) was done. The results of FEC showed that there was no significant difference between the control and treated group (p = 0.081). However, worm burden estimations showed that the number of parasites was significantly higher in the control group compared to the treated group (p < 0.05). This result indicated that feeding Neem had an effect on worm numbers in sheep, but was not reflected in their faecal egg counts. Further work is needed to reconfirm the effect of Neem on helminth infections of sheep.

Matched MeSH terms: Plant Leaves*
Patchy stomatal behavior in broad-leaved trees grown in different habitats

Takanashi S, Kosugi Y, Matsuo N, Tani M, Ohte N

Tree Physiol, 2006 Dec;26(12):1565-78.
PMID: 17169896

Effects of heterogeneity in stomatal behavior on gas-exchange characteristics of leaves from four tree species growing in different climates, including temperate, tropical monsoon and tropical rain forest, were investigated by combining gas-exchange measurements and the pressure-infiltration method. Field observations indicated linear relationships between whole-leaf conductance and the ratio of infiltrated to non-infiltrated leaf area (open stomata area) in Dipterocarpus sublamellatus Foxw. and Neobalanocarpus heimii (King) Ashton in a tropical rain forest in Peninsular Malaysia, whereas the ratio of infiltrated to non-infiltrated area rapidly increased up to the whole-leaf conductance at which the entire leaf was infiltrated in Cinnamomum camphora Sieb. in a temperate evergreen forest in Japan and in Azadirachta indica Juss. in a tropical monsoon area in Thailand. These results strongly suggest small ranges in bell-shaped stomatal conductance distributions in C. camphora and A. indica and bimodal stomatal conductance distributions in D. sublamellatus and N. heimii. The values of normalized maximum carboxylation rate at 25 degrees C (V(cmax25)) derived from gas-exchange measurements were not constant, but decreased with decreasing whole-leaf conductance in D. sublamellatus and N. heimii. A gas-exchange model analysis revealed a linear relationship between whole-leaf conductance and the ratio of infiltrated to non-infiltrated leaf area for bimodal stomatal conductance distributions, whereas for bell-shaped distributions, the relationships were nonlinear. Midday depression of apparent V(cmax25) in these species was mainly caused by bimodal stomatal closure. The bimodal stomatal distribution model could also explain diurnal changes in photosynthetic assimilation and transpiration rates in these species.

Matched MeSH terms: Plant Leaves/physiology*
Laboratory and field tests of the effectiveness of the lemon-eucalyptus extract, Citridiol, as a repellent against land leeches of the genus Haemadipsa (Haemadipsidae)

Kirton LG

Ann Trop Med Parasitol, 2005 Oct;99(7):695-714.
PMID: 16212803

Citridiol is an extract of the leaves of Corymbia citriodora (Myrtaceae), the lemon eucalyptus, and mostly consists of p-menthane-3,8-diol isomers. The effectiveness of this extract as a repellent against land leeches of the genus Haemadipsa (Haemadipsidae), primarily H. sylvestris, was tested in the laboratory and field, in Peninsular Malaysia. The formulation tested, Mosi-guard Natural spray, contained 40% (w/w) Citridiol in a base of ethanol, water and isopropanol. In the laboratory test, specimens of H. sylvestris that were placed within moist, untreated arenas enclosed by treated paper rings made numerous attempts to cross the rings but were prevented or delayed from crossing over, in a dose-dependent manner. Mortality was high among the leeches that attempted to cross over the paper rings that had been sprayed to saturation point but low among the leeches that attempted to cross over paper rings that had only been partially treated, with a droplet-spray. The field study was carried out using indices that were formulated to reflect the severity of leech attack and the degree of repellency. Heavy or moderate spraying of footwear and trouser legs (tucked into socks) not only gave complete protection against bites by H. sylvestris and H. picta but also provided high enough repellency to keep the treated footwear virtually free of leeches. Even a light spray greatly reduced the numbers of leeches on footwear and delayed their progression toward biting the test subjects, although it failed to prevent bites completely. There was no decline in the repellency of the Citridiol when hourly assessments were made over a 6-h test period in the field. The results of the study show that Citridiol is highly repellent as well as toxic to leeches, and can be effectively used to prevent leech bites in the field.

Matched MeSH terms: Plant Leaves/chemistry
Apigenin di- and trirhamnoside from Asplenium normale in Malaysia

Iwashina T, Matsumoto S, Kitajima J, Nakamura T, Kokubugata G, Suleiman M, et al.

Nat Prod Commun, 2010 Jan;5(1):39-42.
PMID: 20184017

Two new flavone rhamnosides, apigenin 7-O-alpha-L-rhamnopyranosyl-(1-->4)-O-alpha-L-rhamnopyranoside and apigenin 7-O-alpha-L-rhamnopyranosyl-(1-->4)-O-alpha-L-rhamnopyranoside-4'-O-alpha-L-rhamnopyranoside were isolated from the fronds of Asplenium normale D. Don, together with two known C-glycosylflavones, vicenin-2 and lucenin-2. The chemical structures of the isolated glycosides were established by UV, LC-MS, characterization of acid hydrolysates, and 1H and 13C NMR spectroscopy.

Matched MeSH terms: Plant Leaves/chemistry
Biomass accumulation and energy conversion efficiency in aromatic rice genotypes

Shahidullah SM, Hanafi MM, Ashrafuzzaman M, Razi Ismail M, Salam MA, Khair A

C. R. Biol., 2010 Jan;333(1):61-7.
PMID: 20176338 DOI: 10.1016/j.crvi.2009.10.002

A field experiment was conducted to evaluate photosynthetic efficiency along with different growth parameters of aromatic rice genotypes. Forty genotypes including three non-aromatic checks exhibited enormous variations for leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR), net assimilation rate (NAR), grain yield, total dry matter, harvest index and photosynthetic efficiency or energy use efficiency (Emu) at panicle initiation and heading stages. Minimum LAI-value was 0.52 in Khazar at PI stage and maximum was 4.91 in Sakkor khora at heading stage. The CGR-value was in the range of 4.80-24.11 g m(-2) per day. The best yielder BR39 produced grain of 4.21 t ha(-1) and the worst yielder Khazar gave 1.42 t ha(-1). Total dry matter (TDM) yield varied from 4.04 to 12.26 t ha(-1) where genotypes proved their energy use efficiency a range between 0.58 to 1.65%. Emu showed a significant positive relation with TDM (r=0.80(**)), CGR (r=0.72(**)) and grain yield (r=0.66(**)). A negative correlation was established between TDM and harvest index and LAI and RGR. Path analysis result showed that NAR at heading stage exerted highest positive direct effect (0.70) on Emu.

Matched MeSH terms: Plant Leaves/growth & development
Plumeria alba flower extract-mediated synthesis of recyclable chitosan-coated cadmium nanoparticles for pest control and dye degradation

Suriyakala G, Sathiyaraj S, Balasundaram M, Murugan K, Babujanarthanam R, Gandhi AD

Bioprocess Biosyst Eng, 2023 Oct;46(10):1483-1498.
PMID: 37552312 DOI: 10.1007/s00449-023-02915-z

In the current scenario, many synthetic chemicals have used long-term to control pests and mosquitoes, leading to the resistance of strains and toxicity effect on human beings. To overcome the adverse problem in recent advances, the scientific community is looking into nanofabricated pesticides and mosquitoes. This study aims to synthesize the recyclable chitosan-coated cadmium nanoparticles (Ch-CdNps) using Plumeria alba flower extract, which was further applied for insecticidal and mosquitocidal activities. The synthesized Ch-CdNps were confirmed by UV spectroscopy and FTIR analysis. The XRD, TEM, and DLS results confirmed the crystallinity with a spherical shape at 80-100 nm. The insecticidal activity proves that Ch-CdNps inhibited Helicoverpa armigera and Spodoptera litura at 100 ppm. In mosquitocidal, LC50 values of larvicidal of 1st instar were 4.116, 4.33, and 4.564 µg/mL, and the remaining three stages of instars, pupicidal, adulticidal, longevity, fecundity, and ovicidal assays inhibit the Anopheles stephensi followed by Aedes aegypti and Culex quinquefasciatus. Further, the first-order kinetics of photocatalytic degradation of methylene blue and methyl orange was confirmed. Based on the obtained results, Ch-CdNps can inhibit the pest, mosquitoes, and photocatalytic degradation.

Matched MeSH terms: Plant Leaves/chemistry

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