Bamboo Species Research Articles

Evaluation of the potential of Yushina alpina bamboo fibers from Cameroon for the manufacture of biocomposites

The Cameroon has two bamboo species indigenous to Africa (the alpine bamboo, Yushina alpina and the savannah bamboo, Oxytenanthera abyssinica), and one largely exotic species, Bambusa vulgaris. However, little on their physical characteristics and strength for the composites materials applications is known for these two indigenous bamboos species in Cameroon. Therefore, in this study, emphasis was laid on the alpine bamboo Y. alpina, to evaluate its potential for biocomposites applications. Y. alpina with ages ranging from 1 to 3 years, 4–5 years, and 7 years were characterized. The mechanical and physical properties of these three age ranges were compared. In the first place, the surface texture of the fibers was examined by scanning electron microscopy. Afterwards, chemical treatment was performed on the fibers with 1 % NaOH. In addition, the chemical bonds of the molecules (functional groups) were identified by Fourier transform infrared spectra (FTIR) and the thermal properties of the fibers were examined with a thermogravimetric analyzer. Furthermore, the fibers density was assessed using the Rilem protocol and a tensile testing machine was used to determine the mechanical properties of the treated fibers with 1 % of NaOH. Finally, a dynamic mechanical analysis of 7-year-old Y. alpina fibers was carry out. The results indicate that the Young's modulus of treated fibers with ages ranging from 1 to 3 years, 4–5 years, and 7 years were around 18 GPa, 10 GPa, and 14 GPa, respectively. In summary, this study underlines two primary points: (1) providing a platform for researchers to better understand the influence of age on the physical and mechanical properties of indigenous bamboo Y. alpina; and (2) providing a platform to validate suitable designs of biocomposites materials with Y. alpina.

Genetic structure of a narrowly distributed species Chimonobambusa tumidissinoda in the Yunnan-Guizhou Plateau, and its implications for conservation

Chimonobambusa tumidissinoda is a narrowly distributed and endangered bamboo species, which is endemic to the Yunnan-Guizhou Plateau and possesses significant ecological and economic value, particularly due to its delectable shoots. In this study, we employed the restriction site-associated DNA sequencing (RAD-seq) method to elucidate the population structure, genetic diversity, and demographic history of C. tumidissinoda across its entire distribution range. Unlike the genetic pattern revealed previously, three distinct genetic groups within the C. tumidissinoda samples were consistently discriminated based on multiple analyses, and low levels of genetic diversity (HO = 0.085, HE = 0.115, π = 0.116) were found. Furthermore, moderate genetic differentiation (FST = 0.070 - 0.095; PhiPT = 0.129 - 0.156) was detected among these groups with Mantel tests suggesting that isolation by distance (IBD) could potentially drive population genetic differentiation in this species. Moreover, demographic analyses incicated that C. tumidissinoda likely experienced a bottleneck event since the Pliocene, which may be attributed to drier and colder winters in Yunnan resulting from intensified Asian monsoon activity. Based on these findings, we suggest that the endangered status of C. tumidissinoda has been underestimated. Conservation measures should be implemented both in situ and ex situ to enhance its adaptability towards future climate fluctuations. Additionally, seed collection for germplasm storage is recommended.

Carbon stocks estimation in the KGPAA Mangkunagoro I Forest Park at collection zone area

Abstract Mangkunagoro I Forest Park is a nature conservation area for plant collection purposes and preserving biodiversity. Moreover, Forest park as a forest also can absorb and store carbon as biomass. It makes forest park play a role in the mitigation of climate change. This research aimed to determine the amount of carbon stock in the Mangkunagoro I Forest Park collection zone. There are 35 plots in total with 20 x 20 m in size taken using systematic sampling. A non-destructive method with allometric equations was used to estimate total biomass and carbon stocks. In the Mangkunagoro I forest park collection zone, 11 species of trees and 3 species of bamboo were found with a total density of 79 trees/ha. Estimated biomass, carbon stocks, and carbon sequestration in the site were 304.24 ton/ha, 142 ton/ha, and 299.68 ton/ha, respectively.

DHFS-ECM: Design of a Dual Heuristic Feature Selection-based Ensemble Classification Model for the Identification of Bamboo Species from Genomic Sequences.

Analyzing genomic sequences plays a crucial role in understanding biological diversity and classifying Bamboo species. Existing methods for genomic sequence analysis suffer from limitations such as complexity, low accuracy, and the need for constant reconfiguration in response to evolving genomic datasets. This study addresses these limitations by introducing a novel Dual Heuristic Feature Selection-based Ensemble Classification Model (DHFS-ECM) for the precise identification of Bamboo species from genomic sequences. The proposed DHFS-ECM method employs a Genetic Algorithm to perform dual heuristic feature selection. This process maximizes inter-class variance, leading to the selection of informative N-gram feature sets. Subsequently, intra-class variance levels are used to create optimal training and validation sets, ensuring comprehensive coverage of class-specific features. The selected features are then processed through an ensemble classification layer, combining multiple stratification models for species-specific categorization. Comparative analysis with state-of-the-art methods demonstrate that DHFS-ECM achieves remarkable improvements in accuracy (9.5%), precision (5.9%), recall (8.5%), and AUC performance (4.5%). Importantly, the model maintains its performance even with an increased number of species classes due to the continuous learning facilitated by the Dual Heuristic Genetic Algorithm Model. DHFS-ECM offers several key advantages, including efficient feature extraction, reduced model complexity, enhanced interpretability, and increased robustness and accuracy through the ensemble classification layer. These attributes make DHFS-ECM a promising tool for real-time clinical applications and a valuable contribution to the field of genomic sequence analysis.

Above-ground biomass of Moso bamboo forests in China influenced by climate, soil and topography: A meta-analysis

Moso bamboo is an essential forest resource in China, covering the largest area and stock of any bamboo species. Four provinces (Fujian, Hunan, Zhejiang, Jiangxi) each have more than 70 million hectares, collectively accounting for 80 % of the total area of Moso bamboo in China. We named these four provinces as the core area for Moso bamboo and the remaining area in other provinces as non-core area. There has been limited research on how climate, topography, and soil factors collectively affect Moso bamboo biomass in both the core and non-core areas. To better understand the variations, data on DBH and individual biomass were gathered from 348 plots from 25 literature sources and a total of 18 plots from four field surveys conducted in 2019. We found evidence that the above-ground biomass of Moso bamboo forests is influenced by a combination of climate, soil nutrients and topography, with different factors playing a more significant role in the core and non-core areas. Moso bamboo had higher individual above-ground biomass in the core area compared to the non-core area. In the core area, above-ground biomass of Moso bamboo was more influenced by climate than by soil nutrients. In this area, annual minimum temperature had a negative effect on above-ground biomass, while precipitation had a positive effect. In contrast, soil total nitrogen had the largest positive effect on above-ground biomass in non-core area. These findings may contribute to the development of a future biomass model for Moso bamboo forests.

Description of a new whitefly genus and two new species (Hemiptera: Aleyrodidae) from the Western Ghats and Andaman Islands, India

Cerafilum gen. nov. is described for Cerafilum ochlandrae sp. nov. and Cerafilum saddlense sp. nov., from India and colonising bamboo species. Cerafilum gen. nov. is compared with the allied genus Aleuromarginatus Corbett and Setaleyrodes Takahashi and diagnoses and illustrations provided, including habitus, line drawings of holotype, diagnostic characteristics, types’ images and scanning electron microscope microphotographs.

Revealing spatial distribution and accessibility of cell wall polymers in bamboo through chemical imaging and mild chemical treatments

Understanding the distribution and accessibility of polymers within plant cell walls is crucial for addressing biomass recalcitrance in lignocellulosic materials. In this work, Imaging Fourier Transform Infrared (FTIR) and Raman spectroscopy, coupled with targeted chemical treatments, were employed to investigate cell wall polymer distribution in two bamboo species at both tissue and cell wall levels. Tissue-level Imaging FTIR revealed significant disparities in the distribution and chemical activity of cell wall polymers between the fibrous sheath and fibrous strand. At the cell wall level, Imaging Raman spectroscopy delineated a distinct difference between the secondary wall and intercellular layer, with the latter containing higher levels of lignin, hydroxycinnamic acid (HCA), and xylan, and lower cellulose. Mild acidified sodium chlorite treatment led to partial removal of lignin, HCA, and xylan from the intercellular layer, albeit to a lesser extent than alkaline treatment, indicating susceptibility of these polymers to chemical treatment. In contrast, lignin in the secondary wall exhibited limited reactivity to acidified sodium chlorite but was slightly removed by alkaline treatment, suggesting stable chemical properties with slight alkaline intolerance. These findings provide valuable insights into the inherent design mechanism of plant cells and their efficient utilization.

Variations and trade-offs in leaf and culm functional traits among 77 woody bamboo species

BackgroundWoody bamboos are the only diverse large perennial grasses in mesic-wet forests and are widely distributed in the understory and canopy. The functional trait variations and trade-offs in this taxon remain unclear due to woody bamboo syndromes (represented by lignified culm of composed internodes and nodes). Here, we examined the effects of heritable legacy and occurrence site climates on functional trait variations in leaf and culm across 77 woody bamboo species in a common garden. We explored the trade-offs among leaf functional traits, the connection between leaf nitrogen (N), phosphorus (P) concentrations and functional niche traits, and the correlation of functional traits between leaves and culms.ResultsThe Bayesian mixed models reveal that the combined effects of heritable legacy (phylogenetic distances and other evolutionary processes) and occurrence site climates accounted for 55.10–90.89% of the total variation among species for each studied trait. The standardized major axis analysis identified trade-offs among leaf functional traits in woody bamboo consistent with the global leaf economics spectrum; however, compared to non-bamboo species, the woody bamboo exhibited lower leaf mass per area but higher N, P concentrations and assimilation, dark respiration rates. The canonical correlation analysis demonstrated a positive correlation (ρ = 0.57, P-value < 0.001) between leaf N, P concentrations and morphophysiology traits. The phylogenetic principal components and trait network analyses indicated that leaf and culm traits were clustered separately, with leaf assimilation and respiration rates associated with culm ground diameter.ConclusionOur study confirms the applicability of the leaf economics spectrum and the biogeochemical niche in woody bamboo taxa, improves the understanding of woody bamboo leaf and culm functional trait variations and trade-offs, and broadens the taxonomic units considered in plant functional trait studies, which contributes to our comprehensive understanding of terrestrial forest ecosystems.

Reponses of morphological and biochemical traits of bamboo trees under elevated atmospheric O3 enrichment

Dwarf bamboo (Indocalamus decorus) is an O3-tolerant plant species. To identify the possible mechanism and response of leaf morphological, antioxidant, and anatomical characteristics to elevated atmospheric O3 (EO3) concentrations, we exposed three-year-old I. decorus seedlings to three O3 levels (low O3-LO: ambient air; medium O3-MO: Ambient air+70 ppb high O3–HO: Ambient air+140 ppb O3) over a growing season using open-top chambers. Leaf shape and stomatal characteristics, and leaf microscopic structure of I. decorus were examined. The results indicated that 1) the stomata O3 flux (Fst) of HO decreased more rapidly under EO3 as the exposure time increased. The foliar O3 injury of HO and MO occurred when AOT40 was 26.62 ppm h and 33.20 ppm h, respectively, 2) under EO3, leaf number, leaf mass per area, leaf area, and stomata length/width all decreased, while leaf thickness, stomatal density, width, and area increased compared to the control, 3) MDA and total soluble protein contents all showed significantly increase under HO (36.57% and 32.77%) and MO(31.91% and 19.52%) while proline contents only increased under HO(33.27%). 4) MO and HO increased bulliform cells numbers in the leaves by 6.28% and 23.01%, respectively. HO reduced the transverse area of bulliform cells by 13.73%, while MO treatments had no effect, and 5) the number of fusoid cells interspace, the transverse area of fusoid cells interspace, and mesophyll thickness of HO significantly increased by 11.16%, 28.58%, and 13.42%, respectively. In conclusion, I. decorus exhibits strong O3 tolerance characteristics, which stem from adaptions in the leaf's morphological, structural, antioxidant, and anatomical features. One critical attribute was the enlargement of the bulliform cell transverse area and the transverse area of fusoid cells interspace that drove this resistance to O3. Local bamboo species with high resistance to O3 pollution thus need to be promoted for sustained productivity and ecosystem services in areas with high O3 pollution.

Iron nanoparticles in combination with other conventional Fe sources remediate mercury toxicity-affected plants and soils by nutrient accumulation in bamboo species

The issue of mercury (Hg) toxicity has recently been identified as a significant environmental concern, with the potential to impede plant growth in forested and agricultural areas. Conversely, recent reports have indicated that Fe, may play a role in alleviating HM toxicity in plants. Therefore, this study's objective is to examine the potential of iron nanoparticles (Fe NPs) and various sources of Fe, particularly iron sulfate (Fe SO4 or Fe S) and iron-ethylene diamine tetra acetic acid (Fe - EDTA or Fe C), either individually or in combination, to mitigate the toxic effects of Hg on Pleioblastus pygmaeus. Involved mechanisms in the reduction of Hg toxicity in one-year bamboo species by Fe NPs, and by various Fe sources were introduced by a controlled greenhouse experiment. While 80 mg/L Hg significantly reduced plant growth and biomass (shoot dry weight (36%), root dry weight (31%), and shoot length (31%) and plant tolerance (34%) in comparison with control treatments, 60 mg/L Fe NPs and conventional sources of Fe increased proline accumulation (32%), antioxidant metabolism (21%), polyamines (114%), photosynthetic pigments (59%), as well as root dry weight (25%), and shoot dry weight (22%), and shoot length (22%). Fe NPs, Fe S, and Fe C in plant systems substantially enhanced tolerance to Hg toxicity (23%). This improvement was attributed to increased leaf-relative water content (39%), enhanced nutrient availability (50%), improved antioxidant capacity (34%), and reduced Hg translocation (6%) and accumulation (31%) in plant organs. Applying Fe NPs alone or in conjunction with a mixture of Fe C and Fe S can most efficiently improve bamboo plants' tolerance to Hg toxicity. The highest efficiency in increasing biochemical and physiological indexes under Hg, was related to the treatments of Fe NPs as well as Fe NPs + FeS + FeC. Thus, Fe NPs and other Fe sources might be effective options to remove toxicity from plants and soil. The future perspective may help establish mechanisms to regulate environmental toxicity and human health progressions.

Redistribution of Qiongzhuea tumidinoda in Southwest China under Climate Change: A Study from 1987 to 2012

Qiongzhuea tumidinoda stands out as an endemic bamboo species of significant conservation importance in Southwest China, particularly in the upper reaches of the Yangtze River. It holds a pivotal role in poverty alleviation through the commercialization of its wood and bamboo shoots. However, the suitable area of this species is undergoing rapid changes due to climate change, resulting in species redistribution and potential losses for bamboo farmers. We utilized 209 presence records and 25 environmental variables from 1987 to 2012 to predict the potentially suitable habitats for Q. tumidinoda using MaxEnt (version 3.4.1), ArcGIS (version 10.8.2), and R (4.3.3). We rigorously screened the recorded data for reliability and accuracy through expert consultations and observer interviews. We performed pre-processing to select the variables with high contributions for modeling, and 11 variables were selected for the final modeling. Our findings reveal that the top three most influential variables associated with Q. tumidinoda’s distribution were the mean monthly potential evapotranspiration (Pet), annual range of air temperatures (Bio7), and mean diurnal air temperature range (Bio2), and the rates of contributions from 1987 to 2012 were 4.8333, 3.5833, and 1.7000. There was a southeastward shift and an elevation increase in the potentially suitable habitats for Q. tumidinoda. The area of potentially suitable habitats in the study region exhibited fluctuating growth, expanding from 3063.42 km2 to 7054.38 km2. The mean monthly potential evapotranspiration (Pet) emerged as a critical determinant shaping the distribution of potentially suitable habitats for Q. tumidinoda. Our study sheds light on the response of Q. tumidinoda to climate change, offering valuable insights for the development and management of plantation industries associated with this species. In the future, to enhance prediction accuracy, researchers could equally consider both organic and inorganic environmental variables. For better preservation of environment and development, Q. tumidinoda could be introduced into nature restoration projects in areas with a suitable habitat or as a commodity that participates in forest carbon sink trading.

The traditional ecological knowledge of the local people of Cijambu Village, Sumedang, Indonesia, on the diversity, utilization, management, and conservation of bamboo

Abstract. Ihsan M, Irawan B, Iskandar J. 2024. The traditional ecological knowledge of the local people of Cijambu Village, Sumedang, Indonesia, on the diversity, utilization, management, and conservation of bamboo. Biodiversitas 25: 1754-1770. Bamboos have been known to play an important role in the socio-economic, cultural, and ecological benefits of rural people in West Java. However, many bamboo gardens have been converted to other land-use types, including commercial vegetable gardens. The study aimed to record local people's Traditional Ecological Knowledge (TEK) in Cijambu, Sumedang, West Java, Indonesia, regarding the diversity, utilization, management, and conservation of ethnobotany and bamboo. The mixed method, combining approaches with an ethnobotanical perspective, was employed in this study through semi-structured and structured interviews with informants. The study results showed a diversity of bamboo landraces with six types of bamboo identified by the community: Awi Tali (Gigantochloa apus), Awi Gombong/Awi Surat (Gigantochloa verticillata), Awi Temen (Gigantochloa atter), Awi Bitung (Dendrocalamus asper), Haur Héjo (Bambusa vulgaris var. vulgaris), and Haur Konéng (Bambusa vulgaris var. striata). Bamboo has 41 uses: 3 ecological uses, 32 economic uses, and 6 socio-cultural uses. Bamboo management involves maintaining and transforming bamboo gardens into mixed gardens, combining vegetables and coffee plants to increase income. Community conservation efforts involve selective logging to ensure the sustainability and regeneration of bamboo. The conservation process is influenced by cultural beliefs and myths, such as refraining from cutting or taking bamboo on Fridays. Bamboo people believe in Tolak Bala, which uses Haur Konéng bamboo.

Establishing the Characteristic Compressive Strength Parallel to Fiber of Four Local Philippine Bamboo Species

Bamboo is considered a sustainable construction material due to its ability to grow quickly and its mechanical properties that are comparable to timber. Contributing to the current effort to establish structural bamboo standards in the National Structural Code of the Philippines (NSCP), this study establishes the characteristic compressive strength of four bamboo species: Bambusa vulgaris (36 samples), Dendrocalamus asper (36 samples), Bambusa blumeana (94 samples), and Guadua angustifolia Kunth (30 samples). The samples were subjected to compressive loading following ISO 22157-1 (2017). The characteristic compressive strength values obtained, according to ISO 12122-1 (2014), were 40.35 MPa for B. vulgaris, 40.21 MPa for D. asper, 46.63 MPa for B. blumeana, and 36.99 MPa for G. angustifolia Kunth. Simple linear analysis, one-way ANOVA, and Welch’s t-test were used to analyze the correlation models and establish a comparative analysis of the effects of nodes and geometric and physical properties on the compressive strength of bamboo samples. In comparisons of the characteristic compressive strengths obtained from this study to the strengths of unseasoned structural timber of Philippine woods, all bamboo species showed higher strength values than did other woods, and bamboos thus have great potential as an alternative construction material to timber.

Comparison and assessment of nutritional composition in shoots of six bamboo species in Southeast China

The introduction of bamboo species is one of the strategies used to enrich edible fresh bamboo shoots resources across diverse regions. However, there is a lack of investigation on the adaptability of bamboo species and the nutritional profiles of their shoots post-introduction. In this study, the nutritional components of bamboo shoots from six bamboo species that have been successfully introduced were compared and evaluated. These six bamboo species possess shoots rich in soluble sugar, soluble protein, and crude fibre. Furthermore, the shoots exhibit significant concentrations of potassium and iron, along with an abundance of amino acids. Notably, the amino acid content is highest in the apical region of the bamboo shoot, followed by the middle section, with the base having the lowest levels. When evaluated through several assessment systems, the shoots exhibited varying scores and rankings. A comprehensive evaluation approach was then utilized to assign final scores and rankings to all six species. Recommendations are provided for the selection of high-quality nutrient-dense bamboo shoots grown in the same field following successful introduction.

MECHANICAL PROPERTIES OF LAMINATED BAMBOO LUMBER MADE OF TROPICAL SPECIES

Bamboo has been the trend for a sustainable material, due to its renewability. Bamboo can grow abundantly throughout the tropical area of the world, such as Latin America, East Asia and Southeast Asia. It is seen that Southeast Asia has variety of bamboo to utilize and many of them are suitable for structural applications. One additional reason is that they are clumping type, so fibers are built stronger. Bamboo is hollow and irregular in sizes and shapes, so it cannot maximize the use out of the materials. Bamboo Laminated Lumber (LBL) is the product to solve bamboo issues on the irregularity be transforming into solid lumber. It can be called the engineered bamboo, which have been transformed conventional form of bamboo using engineering process. This is the same technology as laminated timber. It has more potential to substitute the use of timber. This research is to experiment of making LBL using structural bamboo species that are widely used in Southeast Asia. They are Dendrocalamus Asper, Dendrocalamus Sericeus, Bambusa Multiplex, and Bambusa Blumena. They are tested for mechanical properties; Tension, compression parallel to grain, compression perpendicular to grain, and bending. Those properties are compared to other tropical hardwood and engineered wood. The result shows that LBL of all species are qualified for medium-hardwood quality, while B.Multiplex lumber performs best overall. The rest still have great mechanical properties and can be qualified some structural lumber in order to reduce the use of timber.

Bamboo Structure and Its Impact on Mechanical Properties: A Case Study of Bambusa arundinaceae

Bamboo is a naturally occurring composite material, which exhibits a decomposable structure with varying composition. The distinct structural features of bamboo contribute to its exceptional strength and flexibility, making it an excellent choice for construction purposes. However, only a limited portion of bamboo species has been studied for its mechanical properties, and research on Bambusa arundinaceae has primarily focused on its pharmaceutical values. Therefore, we investigated the relationship between the structural characteristics of B. arundinaceae and its mechanical properties using axial compression experiments and tangential bending experiments. The results showed that the distribution density of vascular bundles (VBs) of B. arundinaceae ranged from 1.98 to 4.34 pcs/mm2,while the volume fraction of fiber sheaths (FSs) ranged from 35.82 to 42.58%. The average compressive strength, flexural strength, and flexural elasticity modulus were 113.99 MPa, 239.07 MPa, and 17.39 GPa, which were 97.56%, 64.07%, and 66.09% higher than those of moso bamboo (Phyllostachys edulis), respectively. The compressive strength, flexural strengths, and elasticity modulus of B. arundinaceae were positively correlated with both the distribution density of VBs and the volume fraction of FSs. These insights are crucial for the advancement of durable and efficient materials in diverse sectors including construction and manufacturing.

Multilevel analysis of six species of Phyllostachys bamboo and Arundo donax: preliminary survey on Italian grown stands

The paper focuses on a multilevel analysis considering six species of bamboo of the Phyllostachys family (P. bambusoides, edulis, iridescens, viridiglaucescens, violacescens, and vivax) and Arundo donax grown in temperate climates, most of them not already studied in the literature. The analysis is divided into three levels. The analysis at the first level (the microscopic scale) includes an anatomical study to assess the shapes and dimensions of the vascular bundles and the sclerenchymatic and parenchymatic tissues. At the second mesoscale level, the percentage and distribution of the fibres, voids and parenchyma are calculated. At the third level, the macroscopic one, a discussion of the influence of the microscopical properties on mechanical properties is carried out. Despite the limited number of specimens analysed at the microscale level, differences between species emerged from the analysis and influenced the macroscopic characteristic values. In particular, the morphology of the components differs, especially in the case of Arundo donax, which presents a unique distribution of its components along the culm wall. Different contents of each component are observed for the species analysed. Moreover, an innovative analysis that focuses on the presence and distribution of voids is presented, which have a fundamental role in the mechanical behaviour of this material. The analysis did not account for the influence of the environment on composition or anatomical and physical characteristics.

Different Parts of a Dendrocalamus brandisii (Munro) Kurz Shoot, Rather Than the Shoot’s Height, Are More Indicative of Its Nutrient Properties

Bamboo shoots are considered as a healthy food and are popular in Asian cooking. The distribution of nutrients and their dynamics during the growth of bamboo shoots play a crucial role in guiding the harvesting and processing of bamboo shoots. In this study, Dendrocalamus brandisii (Munro) Kurz, an important bamboo species for harvesting fine edible shoots in southern China and Southeast Asia, was used to measure several indicators related to the edibility and nutritional value of fresh shoots across five height grades (H1: 20~30 cm; H2: 31~40 cm; H3: 41~50 cm; H4: 51~60 cm; and H5: 61~70 cm). The results indicated that, although the nutrient and mineral elements showed an increasing (crude fiber content, CFC), decreasing (total soluble sugars content, TSSC; ash content, AC; Fe; Zn), or fluctuating (soluble protein content, SPC; P; K; Ca) pattern with the growth of bamboo shoots, both the CFC and TSSC showed the highest values in the lower part at five growth heights, indicating that carbohydrates were mainly enriched in the bases of bamboo shoots. The SPC, AC, and other mineral elements were higher in the upper part, especially in H1–H3. Combined with the relatively high activity of metabolic enzymes (sucrose-phosphate synthase, SPS; neutral invertase, NI) in the upper part of bamboo shoots (although not statistically significant), it can be inferred that the shoot tip may be the main tissue for early nutrient synthesis and metabolism. Compared with the shoot height, different parts of a D. brandisii bamboo shoot are more indicative of its nutrient properties. Although all heights of bamboo shoots showed an abundance of nutrients and mineral elements, bamboo shoots with a height of less than 40 cm had a higher TSSC, AC, Fe, and Zn, and a lower CFC, thus having a better balance between nutrients and edibility.

EKSTRATIF BEBERAPA JENIS DAUN BAMBU

This research aims to determine the extractive content based on the type of solvent in several types of bamboo leaves. Air dried bamboo leaves were chopped into particles and ground using a blender. After it was finely ground, the sago waste was sieved using 40 and 60 mesh sieves, to obtain bamboo leaf powder with a size of -40/+mesh (TAPPI T 257 cm-85) for testing chemical components. Testing for bamboo leaf powder includes testing the content of cold-water soluble extractive substances, the content of hot-water soluble extractive substances, and the levels of ethanol-toluene soluble extractives. The results of the research showed that the type of bamboo leaf had a significant effect on the levels of cold-water soluble extractive substances, the levels of hot-water soluble extractives, and the levels of ethanol-toluene soluble extractives. Cold water soluble extractive content was 8.4149-10.6612%, hot water soluble extractive 9.1871-10.7843% and ethanol-toluene soluble extractive 4.2009-7.1242%. The solubility of extractives in hot water tends to be higher for all types of leaves and suanggi bamboo tends to contain higher extractives for each type of solvent.

Effects of microwave-assisted softening treatment on dynamic mechanical properties and chemical composition of bamboo

In response to the global plastic pollution crisis, a sustainable manufacturing strategy for replacing plastic with bamboo is proposed. Bamboo softening treatment is important for bamboo processing. In this study, the effects of microwave-assisted alkali/boiling treatment on the microstructure, chemical composition, glass transition temperature, compression ratio, and surface wettability of the bamboo species Phyllostachys edulis and Dendrocalamus sinicus were studied. Microwave-assisted alkali (0.1 % NaOH)/boiling (2 h) treatment increased the flexibility and processability of both species. Dynamic mechanical analysis showed that the storage modulus of P.edulis slices was reduced from 6429 MPa to 5128 MPa, loss modulus was reduced from 134.1 MPa to 100.6 MPa, and glass transition temperature was reduced from 204.25 ℃ to 100.39 ℃ indicating that bamboo stiffness was reduced and elasticity was enhanced. With the temperature increase, the alkali solution destroyed the dense fiber structure and broke the bonds between lignin, cellulose, and hemicellulose. The glass transition temperature decreased in P.edulis by 103.86℃, which was 1.14-times higher than that of D. sinicus, and the compression ratio increased form 10.52–37.58 %, which indicated better thermoplasticity compared with D.sinicus. The vascular bundles and thin-walled cells of the specimens showed different degrees of shrinkage and deformation, and the hydrophobicity of bamboo increased resulting in improved thermal stability and optimal process conditions, providing an effective solution for the realization of replacing plastic with bamboo. This lays the theoretical foundation for subsequent furniture-bending components and molded products.