Agronomic management of a crop, including the application of fertilizers and biological inoculants, affects the phenol and flavonoid contents of plants producing these metabolites. Guadua angustifolia Kunth, a woody bamboo widely distributed in the Americas, produces several biologically active phenolic compounds. The aim of this study was to evaluate the effect of chemical and organic fertilizers together with the application of biological inoculants on the composition of phenolic compounds in G. angustifolia plants at the nursery stage. In 8-month-old plants, differences were observed in plant biomass (20.27 ± 7.68 g) and in the content of total phenols and flavonoids (21.89 ± 9.64 mg gallic acid equivalents/plant and 2.13 ± 0.98 mg quercetin equivalents/plant, respectively) when using the chemical fertilizer diammonium phosphate (DAP). No significant differences were found owing to the effect of the inoculants, although the plants with the application of Stenotrophomonas sp. on plants fertilized with DAP presented higher values of the metabolites (24.12 ± 6.72 mg gallic acid equivalents/plant and 2.39 ± 0.77 mg quercetin equivalents/plant). The chromatographic profile of phenolic metabolites is dominated by one glycosylated flavonoid, the concentration of which was favored by the application of the inoculants Azospirillum brasilense, Pseudomonas fluorescens, and Stenotrophomonas sp. In the case study, the combined use of DAP and bacterial inoculants is recommended for the production of G. angustifolia plant material with a high content of promising biologically active flavonoids or phenolics.

This study evaluated the ultrasound-assisted extraction of phenolic compounds from Guadua angustifolia leaves, along with their optimization using response surface methodology. The effects of two sonication process conditions were determined using a central composite experimental design, with three levels (low, medium, and high) evaluated for time (10, 20, and 30 min) and temperature (20 °C, 35 °C, and 50 °C). A total of 12 experiments with four replicates were conducted at the central point, with the total phenol and flavonoid contents determined using the Folin-Ciocalteu colorimetric method and complexation with AlCl₃, respectively. The optimized extract was analyzed using ultra-performance liquid chromatography (UPLC), and the antioxidant capacity of the optimized extract was determined by DPPH• (2,2-Diphenyl-1-Picrylhydrazyl) and ABTS^•+ (2,2′-Azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) assays. Extraction at 50 °C for 20 min was found to favor the extraction of phenol and total flavonoids. The experimental validation of the total phenol and flavonoid content produced values of 7.39 mg gallic acid equivalents per gram of dry matter and 1.55 mg quercetin equivalents per gram of dry matter, respectively. These values suggest that the extraction process is reproducible, with a relative standard deviation of 22.9 % and 14.1 %, respectively. The chromatographic profile showed that optimization favored the visualization of phenolic compounds compared to the non-optimized extract. The optimized extract had higher antioxidant capacity than the non-optimized extract, with values of 209.23 and 144.76 μmol Trolox per gram extract for the DPPH• and ABTS^•+ techniques, respectively. Thus, the conditions evaluated in the ultrasound-assisted extraction were an efficient technique capable of extracting the maximum amount of phenolic compounds with antioxidant activity from the leaves of G. angustifolia, showing its potential application in various industries.

The genus Passiflora comprises more than 500 species distributed in tropical and semitropical regions. With a great diversity of species, it is estimated that one-third is found in Colombian territory. Besides the food importance, Passiflora species are important sources of biologically active compounds, such as flavonoids. The most important symbiosis between soil fungi and vascular plants related to plant nutrition and tolerance to stress conditions is mycorrhizae. Passiflora species form arbuscular mycorrhizae, with several species of Glomeromycota. This association has been reported to alter the production of secondary metabolites. Thus, the objective of this study was to determine the relation between flavonoid content, mycorrhization, and soil nutritional content of Passiflora alata, Passiflora quadrangularis, Passiflora maliformis, and Passiflora ligularis in Colombian crops. The extracts were prepared and analyzed using UPLC/PDA-MS, and total flavonoids were quantified with the method of AlCl₃. Soil characteristics, including nutritional content and percentage of colonization by arbuscular mycorrhizal fungi, were also determined. All variables were analyzed using Spearman's correlation and principal component analysis. Chromatographic analysis of the extracts allowed us to visualize the different flavonoid compositions of each extract, identifying several C-glycosylflavonoids. In this paper, we report for the first time the presence of luteolin-8-C-rhamnosyl-4'-O-glucoside, apigenin-6-C-arabinosyl-7-O-glucoside, and orientin for P. maliformis. Statistical analysis showed a negative correlation between available phosphorus (ρ = -0.90, p = <0.05) and magnesium (Mg) saturation (ρ = -0.70, p = <0.05) on flavonoid content, whereas the calcium magnesium (Ca/Mg) ratio was positively correlated (ρ = 0.70, p = 0.1). These results contribute to understanding the relationship between flavonoid-mycorrhization-soil nutritional content on Passiflora spp.

Bamboo plants are widely used in Asian traditional medicine for various health issues and exhibit therapeutic potential. Guadua species are renowned bamboos for their high phenolic compound content, including flavonoids and hydroxycinnamic acid derivatives, and possess noteworthy biological properties. Despite this, there is a notable scarcity of research on the chemical and biological aspects of Latin American bamboo leaf extracts (BLEs), especially concerning the Guadua genus. This study aimed to employ a metabolomics approach to integrate the phytochemical and activity profiles of BLEs to identify potential bioactive markers. We determined the metabolic fingerprints of 30 BLEs through HPTLC, HPLC-DAD, UHPLC-QTOF-MS, and ¹H-NMR analyses and screened for antioxidant and cytotoxic activities using ABTS, DPPH, and MTT methods. Ultimately, correlation analyses were performed by using chemometric methods and molecular networking. Our findings present a comprehensive chemical characterization, encompassing 40 flavonoids and 9 cinnamic acid derivatives. Notably, most of these compounds have been reported for the first time within the genus, signifying novel discoveries. Additionally, certain compounds identified in other species of the subfamily Bambusoideae provide valuable comparative insights. These compounds demonstrated a significant correlation with antioxidant potential, with values exceeding 100 and 30 μmol of TE/g of extract for ABTS and DPPH, respectively, in the samples. Extracts from G. incana and G. angustifolia exhibited potent cytotoxic effects with IC₅₀ values of 1.23 and 4.73 μg/mL against HCT-116 colon cancer cells, respectively. Notably, glycosylated flavones showed a strong correlation with cytotoxicity. These new findings significantly contribute to our understanding of the chemical composition and biological properties of these often overlooked bamboo species, providing them with important added value and alternative use.

Guadua angustifolia produces phenolic compounds, and this production may be influenced by the application of chemical, organic, and biological fertilizers. Currently, the effect of such fertilizers on the synthesis dynamics of this group of metabolites in bamboo is unknown. In this study, the total phenolic content (TPC) and total flavonoid content (TFC) in the leaves of plants fertilized with diammonium phosphate (DAP) and humus in combination with the biofertilizers Promofort^®, Azospirillum brasilense, Pseudomonas fluorescens, and Stenotrophomonas sp. were determined using colorimetric techniques across three sampling events (four, five, and seven months after planting). Additionally, an approximation of the bacterial profile of G. angustifolia roots was performed using the DGGE-PCR fingerprint technique. Through repeated measures ANOVA (rmANOVA), it was determined that there is no statistically significant three-way interaction between humus or DAP application, biological fertilizers, and time for either TPC or TFC. However, there were interactions between the sampling event and the application of biological fertilizers for both TPC and TFC, with the latter being promoted by the application of Promofort^®. Finally, NMDS analyses and heatmaps with hierarchical clustering showed that the composition and abundance of OTUs in the bacterial profile varied with fertilization type and increased over time.

Guadua angustifolia, a native bamboo species of ecological and economic importance, has been widely studied in Colombia. This study focused on evaluating the genetic diversity and population structure of G. angustifolia from six natural populations in the Department of Nariño, Colombia, using restriction site-associated DNA sequencing (RADseq). A total of 224,996 high-quality SNPs were identified across 48 individuals. Observed heterozygosity (Ho) ranged from 0.398 in Consacá to 0.78 in Tumaco, while expected heterozygosity (He) was lower in all cases, ranging from 0.291 to 0.597. All populations exhibited negative inbreeding coefficients (FIS), from −0.316 to −0.763, indicating an excess of heterozygotes and suggesting predominantly outcrossing reproduction. Analysis of molecular variance (AMOVA) revealed that most genetic variation resides within individuals (92.54%), with low differentiation among populations (7.46%). Population structure and phylogenetic analyses identified two main genetic clusters, likely reflecting the origin of the planting material. Our results revealed that chromosomes CM070500.1, CM070502.1, CM070503.1, CM070504.1, CM070508.1, and CM070510.1 exhibited the highest SNP density, suggesting the presence of genomic regions with elevated variability. In contrast, chromosomes with lower SNP density suggested conservated genes related to Flavone Synthase II. This study is the first to evaluate genetic materials from the Department of Nariño. These findings highlight the significant genetic diversity in G. angustifolia and the density of SNPs, and provide suggestions for conservation planning and the development of targeted breeding programs for this non-model tropical species.