The leaf, inner bark and latex cyanide potential of Hevea brasiliensis: Evidence for involvement of cyanogenic glucosides in rubber yield

Moreira

Journal of Plant Interactions

et al. 2013

The presence of high cyanogenic glycoside concentrations may predispose plant to the tapping panel dryness (TPD). This study aimed to verify the involvement of cyanogenesis in the reduction of latex stability and in the establishment of TPD. The following parameters were evaluated in rubber tree trunk bark: concentration of cyanogenic glycosides with determination of cyanogenic potential (HCNp) and latex stability with lutoid bursting index (LBI). The study of the relationship between cyanogenesis and TPD was performed by semiquantitative comparison of hydrogen cyanide (HCN) gas released from the trunk bark under the following conditions: without (0%) and with (100%) TPD. The positive correlations between HCNp values and LBI indicate that cyanogenic glycosides present in the bark reduce latex stability, resulting in low yield due to the short duration of flow during tapping. The largest amount of HCN released by trunk bark tissues when the plant exhibits TPD symptoms strengthens the evidence of the involvement of this compound in the establishment of this condition.

Section: Resultssupporting

confidence: 91%

Section: Resultsmentioning

confidence: 96%

Relationship between cyanogenesis and latex stability on tapping panel dryness in rubber trunk girth

Moreira

Journal of Plant Interactions

et al. 2013

“…H 2 O 2 in chlorotic leaves) [13]. Cyanogenic diglucosides in Hevea brasiliensis (rubber tree) have been demonstrated to function as a transport and storage form of renewable nitrogen, carbon and glucose for both germination and latex production [14,15]. In cassava, girdling experiments demonstrated that cyanogenic glucosides are synthesized in the shoot apex and transported to the root.…”

Section: Introductionmentioning

confidence: 99%

A recycling pathway for cyanogenic glycosides evidenced by the comparative metabolic profiling in three cyanogenic plant species

Pičmanová

Neilson

Motawia

et al. 2015

Biochemical Journal

120

126

N. (2015). A recycling pathway for cyanogenic glycosides evidenced by the comparative metabolic profiling in three cyanogenic plant species. Biochemical Journal, 469(3), 375-389. DOI: 10.1042/BJ20150390 1 A RECYCLING PATHWAY FOR CYANOGENIC GLYCOSIDES EVIDENCED BY THE COMPARATIVE METABOLIC PROFILING IN THREE CYANOGENIC PLANT SPECIES ABSTRACTCyanogenic glycosides are phytoanticipins involved in plant defence against herbivores by virtue of their ability to release toxic HCN upon tissue disruption. In addition, endogenous turnover of cyanogenic glycosides without the liberation of HCN may offer plants an important source of reduced nitrogen at specific developmental stages. To investigate the presence of putative turnover products of cyanogenic glycosides, comparative metabolic profiling using LC-MS/MS and HR-MS complemented by ion-mobility mass spectrometry was carried out in three cyanogenic plant species: cassava, almond and sorghum. In total, the endogenous formation of 36 different chemical structures related to the cyanogenic glucosides linamarin, lotaustralin, prunasin, amygdalin and dhurrin was discovered, including di-and triglycosides derived from these compounds. The relative abundance of the compounds was assessed in different tissues and developmental stages. Based on results common to the three phylogenetically unrelated species, a potential recycling endogenous turnover pathway for cyanogenic glycosides is described in which reduced nitrogen and carbon are recovered for primary metabolism without the liberation of free HCN. Glycosides of amides, carboxylic acids and anitriles derived from cyanogenic glycosides appear as common intermediates in this pathway and may also have individual functions in the plant. The recycling of cyanogenic glycosides and the biological significance of the presence of the turnover products in cyanogenic plants open entirely new insights into the multiplicity of biological roles cyanogenic glycosides may play in plants.Abbreviations: HR-MS, high-resolution mass spectrometry; EIC, extracted ion chromatogram; IM-MS, ionmobility mass spectrometry; ATD, arrival time distribution; CID, collision-induced dissociation 2 SUMMARY STATEMENTA potential recycling pathway for cyanogenic glycosides is presented wherein reduced nitrogen and carbon are recovered for primary metabolism without HCN liberation. Common types of glycosylated pathway intermediates were found in three cyanogenic plant species: cassava, almond and sorghum.

“…The optimum harvesting time still needs to be considered for influence on latex yield, the amount of available leaves, and the leaf protein content. In addition, rubber leaves cyanide content is influenced not only by leaf age, but also by latex tapping activities and sunlight exposure; young leaves harvested in the shade or during the night have the highest cyanide content [69]. Based on the development phases of rubber trees (Fig.…”

Section: Leavesmentioning

confidence: 99%

Valorisation of Proteins from Rubber Tree

WIDYARANI

Coulen

Sanders

et al. 2016

Waste Biomass Valor

Purpose The objective of this study was to identify the availability, possible applications, and economic potential of proteins that are present in different parts of the rubber tree. Proteins from non-food sources can be used in e.g. animal feed or biochemicals production with no or little competition with food production, rendering them important biobased feedstock. Rubber tree is primarily grown for its latex that is used in rubber production. Indonesia has the largest rubber plantation area that is mostly owned and run by smallholder farmers. Using non-latex fractions from the rubber tree may generate additional income, and increase the economics of rubber plantations in general. Methods Several biomass streams from the rubber tree and subsequent latex processing were considered. Data were compiled from literature, a case study, and interviews with researchers, smallholder farmers, and managers at rubber processing plant and plantation. Results Latex waste streams, seeds, and leaves were considered to have the highest potential based on the amount of available proteins, and processes to isolate proteins from these streams were proposed. Isolation of specific functional properties from natural sources requires complex (and expensive) separation processes and therefore only economically feasible when specific use of the protein(s) for high value applications can be identified. Purification of many interesting proteins from latex fractions has already been described. Processing of seeds and leaves may also yield useful proteins for food, other purposes, and also still unknown high value applications. Conclusions A biorefinery concept can be applied to obtain multiple products from the seeds and leaves, and protein extraction can be performed with available knowledge and technology. Small scale processing can be more beneficial for the farmers, especially if the products are used locally for feed.