1H NMR Combined with Multivariate Statistics for Discrimination of Female and Male Flower Buds of Populus tomentosa

Abstract

1H Nuclear Magnetic Resonance (1H NMR) combined with multivariate statistics was adopted to discriminate female and male flower buds of Populus tomentosa in the study. Samples of 11 female and 16 male flower buds of P. tomentosa were collected in Beijing, China. 1H NMR spectra were acquired on a 400 MHz spectrometer. In total, 30 chemical compounds were identified with standards and literature according to chemical shifts, peak areas, and multiplicity. Principal component analysis (PCA), hierarchical clustering analysis (HCA), and supervised orthogonal partial least squares-discriminant analysis (OPLS-DA) were applied to discriminate female and male flower buds. An apparent grouping trend (R2X, 0.809; Q2, 0.903) between female and male groups was exhibited with PCA and HCA. The two groups were also well discriminated with OPLS-DA (R2X, 0.808; R2Y, 0.976; Q2, 0.960). Combined with variable importance in projection (VIP) > 1.0 and p < 0.05 of OPLS-DA, it was found that the content of daucosterol, β-sitosterol, ursolic acid, and betulonic acid in male group was higher than that in female, which should be the key differences of chemical constituents in female and male flower buds of P. tomentosa. The study demonstrated that 1H NMR combined with multivariate statistics could be used to discriminate female and male plants and clarify differences, which provided a novel method to identify the gender of dioecious plants.

Comprehensive metabolomic variations of hawthorn before and after insect infestation based on the combination analysis of 1H NMR and UPLC-MS

“…A total of 32 metabolites were identified and assigned to amino acids, sugars, phenolic acids, and flavonoids. All identified metabolites were carefully compared with the standards, databases and earlier reports ( Nie et al, 2019 ; Xu et al, 2021 ; Yan et al, 2020 ). Their detailed information were shown in Table S1 .…”

“…The preparation of 1 H NMR samples was described references with minor modifications ( Xu et al, 2021 ). The powder samples were weighed accurately (1.0 g), put into a 50 mL centrifuge tube, mixed with 25 mL extraction solvent ( Table 1 ), and weighed.…”

“…Meanwhile, the regions of δ 3.38–3.28 ppm corresponding to residual CD 3 OD signal and δ 5.08–4.75 ppm corresponding to imperfect D 2 O suppression were discarded. All remaining spectral segments were normalized to the sum of spectra for reducing variations resulted from the concentration inconsistency before chemometrics analysis ( Li et al, 2018 ; Xu et al, 2021 ; Zhao et al, 2019 ). The metabolites were identified by consulting literatures and HMDB ( http://www.hmdb.ca/ ) according to chemical shifts, peak areas, and multiplicity.…”

The Difference of Volatile Compounds in Female and Male Buds of Trichosanthes anguina L. Based on HS-SPME-GC-MS and Multivariate Statistical Analysis

“…The plant of which female and male flowers grow in different plants is called a dioecious plant, but in the same plant is known as a monoecious and diclinous plant. There are many differences in apparent structure, physiological function, and chemical components between female and male flowers of dioecious plants, such as Populus tomentosa (family Salicaceae) [ 12 ], Herpetospermum pedunculosum (family Cucurbitaceas), and T. kirilowii [ 13 , 14 ]. For monoecious and diclinous plants, the difference between female and male flowers also exists; for example, the chemical compounds from flowers of Cucurbita moschata (family Cucurbitaceas) [ 15 ] and the flower morphology of Croton sarcopetalus (family Euphorbiaceae) [ 16 ].…”