High-quality Piper laetispicum (Piper laetispicum C. DC) is the key to the development of foods, natural medicines, and cosmetics. Its crude fat, ash, piperine, protein, and aroma compounds were determined in this experiment. Principal component (PCA) and hierarchical cluster analyses (HCA) were used to evaluate the aroma compounds at different developmental stages. The main aroma compounds identified using steam distillation combined with GC-MS were sabinene (34.83–76.14%), α-copaene (5.11–19.51%), linalool (2.42–15.70%), trans-caryophyllene (2.37–6.57%), α-pinene (1.51–4.31%), and germacrene D (1.30–4.10%). The aroma metabolites at different developmental stages were analysed using non-targeted metabolomes, and linalool was found to be the most abundant. Based on the experimental results, there were more nutrient compounds in young Piper laetispicum than in the last three developmental stages. The aromatic metabolites contributed the most to PC1. There were also more different metabolites of aroma between the young and expanding stages. Therefore, regarding quality, young fruits have great potential.

Mulching cultivation with agricultural wastes is the main production pattern of coffee at present, but the effect of mulching cultivation on photosynthetic physiological processes of coffee plants is still not clear. Therefore, a randomized block design was adopted to establish a field experiment by one-year-old Coffee Canephora seedlings in this study. There were four types of mulch treatments, including non-mulch coffee waste (C), mulching coffee litter (L), mulching coffee cascara (cherry pericarp, P), and mulching coffee litter and cascara (LP) in this field experiment. Soil properties and microenvironment (e.g., moisture, temperature, pH, bulk density, organic matter content, alkali-hydrolyzed nitrogen content, available potassium content, and available potassium content), agronomic traits (e.g., specific leaf area, leaf area index, plant height, and relative chlorophyll content), and photosynthetic indices (e.g., photosynthesis, transpiration, respiration, stomatal conductance, intercellular CO₂ concentration, water use efficiency, and carbon use efficiency) were investigated to determine the effects of different coffee waste mulches on the photosynthetic physiology of coffee seedlings. The results show that coffee litter and cascara mulch significantly reduced soil temperature by 0.42 or 0.33 °C, respectively, and coffee litter rather than cascara mulch significantly increased the soil’s available potassium content by 46.28%, although coffee waste mulch did not affect other soil properties or microenvironment indices; coffee cascara mulching significantly increased the specific leaf area and net and gross photosynthesis of coffee by 45.46%, 78.33%, and 91.72%, respectively, but the mulching treatments did not affect stomatal conductance, transpiration, or carbon use efficiency in this study. Additionally, coffee cascara mulching increased leaf respiration and net and gross water use efficiency by 109.34%, 80.54%, and 104.95%, respectively. The coffee cascara mulching alone had the most significant positive impact on the photosynthetic index, followed by a combination of litter and cascara, litter alone, and the control treatment. The observed variations in the coffee photosynthetic index may be attributed to the reduction of soil temperature caused by mulching treatments rather than the increase in soil nutrients content. These results indicate that coffee cascara mulching could effectively promote photosynthesis and the growth of coffee seedlings by improving the soil microenvironment.

Cymbopogon citratus (DC.) Stapf (lemongrass), a globally significant medicinal and aromatic plant, is widely used in food and pharmaceutical industries owing to its bioactive essential oil. However, conventional whole‐plant extraction methods face challenges such as inconsistent oil quality and suboptimal stability. To elucidate the effects of cultivation environments and plant tissues on oil quality, this study categorized lemongrass plants into shaded and natural light exposure groups. Essential oils were extracted from leaves and stems using steam distillation, followed by compositional analysis using Headspace Solid‐Phase Microextraction (HS‐SPME) coupled with Gas Chromatography–Mass Spectrometry (GC–MS). The investigation focused on how varying radiation intensities influenced physicochemical properties and volatile components of essential oils from various plant parts. Results demonstrated that both physicochemical properties and volatile compositions of lemongrass essential oils exhibited minimal sensitivity to variations in radiation intensity treatments. Leaf‐derived essential oil exhibited a significantly higher yield than stem oil by 54.48%, but their refractive indices and chromatic aberration values did not differ substantially. Leaf oil contained markedly elevated levels of heterocyclic compounds, ethers, and aldehydes than those in stem oil by 14.61%, 10.83%, and 1.57%, respectively, while hydrocarbons were lower by 6.1%. The primary volatile constituents characterizing lemongrass quality—geraniol and citral (specifically 2,6‐octadienal, 3,7‐dimethyl‐, (E)‐)—were significantly more abundant in the leaves than in the stems by 8.64% and 7.20%, respectively ( p < 0.01). Therefore, lemongrass essential oil extracted from leaves cultivated under natural light conditions demonstrated the highest oil yield and superior quality attributes. The integration of natural light cultivation with selective leaf harvesting proposes a promising strategy to enhance lemongrass oil quality. This methodology establishes a theoretical basis for advancing downstream processing techniques and developing high‐value products derived from lemongrass essential oil.

Robusta coffee (Coffea canephora) possesses great industrial potential, whereas its intrinsic flavor defects compromise market competitiveness. Honey processing utilizing residual pulp and mucilage is capable of improving green coffee quality; nevertheless, the absence of quantitative research regarding graded pulp retention limits its industrial application. In this study, fermentation experiments with gradient retention of coffee cherry pulp were conducted to clarify the differential regulatory effects of varying coffee cherry pulp-retention amounts on physicochemical properties, functional components and volatile flavor precursor compounds of Hainan Robusta coffee. Quantitative scoring of coffee quality using international standard cup measuring instruments and the grey relational analysis was further employed to comprehensive quality assessment. Compared with the 0% coffee cherry pulp-retention treatment, all other treatments showed higher levels of selected functional components and volatile flavor precursor compounds. The 66% coffee cherry pulp-retention treatment enriched key roasting flavor substrates: sucrose, organic acids, pyrazines, and esters were increased by 8.74%, 26.58%, 80.66% and 30.18%, respectively. Meanwhile this treatment exhibited significantly lower protein and alkaloid contents than the 100% and 33% coffee cherry pulp-retention treatments, and significantly lower flavonoid content than the 0% and 33% coffee cherry pulp-retention treatments. This treatment exhibited remarkably excellent cup scores by 80.35 and superior comprehensive quality, outperforming the other treatments by 6.05–18.51%. This study identifies the optimal coffee cherry pulp-retention ratio for Robusta coffee post-harvest honey processing, providing theoretical basis and feasible technical references for the quality improvement, standardized processing and industrial promotion of local Robusta coffee.

Improper disposal of coffee-processing by-products can cause environmental pollution, greenhouse gas emissions, and resource loss, whereas their reuse in coffee plantations may support sustainable production. This review systematically examines the material properties, stabilization methods, field application pathways, agronomic effects, quality responses, and environmental risks of coffee-pulp-type by-products in cultivation. Relevant studies published up to June 2026 were retrieved from Web of Science, Scopus, ScienceDirect, SpringerLink, Google Scholar, and CNKI and qualitatively synthesized along the soil–plant–quality continuum. Current evidence suggests that properly stabilized materials, applied at appropriate rates, can improve soil organic matter, structure, water and nutrient retention, microbial activity, plant growth, photosynthesis, and crop yield in plantations. They may also indirectly influence green bean quality by regulating sugars, amino acids, chlorogenic acids, and caffeine. However, these effects depend strongly on material properties, maturity, application rate, coffee genotype, soil and climatic conditions, and management practices. Excessive or insufficiently decomposed materials may cause soil acidification, phytotoxicity, oxygen depletion, nutrient imbalance, and yield–quality trade-offs. Overall, recycling within plantations can turn processing waste into farm inputs, reinforce on-farm carbon and nutrient cycles, ease disposal burdens, and advance BCG and wider circular-economy principles in practice.