The date is a well-established and important crop that holds economic significance. However, a substantial amount of waste in the form of low-grade dates and date pits is generated and accounts for 10 to 15% of the total production. Given the substantial amount of nutrients in these by-products and the large volume of waste generated, there is a promising opportunity to utilize them to create valuable commodities like fiber and phenolic compounds, which hold a high market value. This review presents a summary of the chemical and nutritional composition of dates and their by-products and aims to investigate the possibility of utilizing date processing by-products and waste as an eco-friendly resource for various chemical and biological processes like composting and extraction of value-added compounds, as well as providing insight into the date processing industry and typical methods employed for the beneficial use of date waste. In addition, this review also addresses the current challenges and future perspectives in date waste valorization expectations.

A three-factor, three-level, face-centred cubic design was adopted to investigate the effect of three pre-treatment parameters, namely sodium hydroxide-to-dry biomass ratio [0.00, 0.05, and 0.10 (w/w)], lime-to-dry biomass ratio [0.00, 0.05, and 0.10 (w/w)] and residence reaction time (24, 96, and 168 h), at moderate temperature (21°C) on 24-h cumulative gas production (GP₂₄) and delignification, as the response variables. Under the optimal pre-treatment conditions of NaOH-to-dry biomass ratio of 0.09 (w/w), lime-to-dry biomass ratio of 0.09 (w/w) and residence time of 160.3 h, the model predicted 151.6 mL gas/g organic matter (OM) versus the experimental value of 147.2 mL gas/g OM. Under the optimal conditions of NaOH-to-dry biomass ratio of 0.10 (w/w), lime-to-dry biomass ratio of 0.08 (w/w) and residence time of 156.8 h, sugarcane bagasse (SCB) was maximally delignified by 41.2%, whereas the model predicted 43.6% delignification. Under the optimal conditions determined for GP₂₄, the neutral detergent fibre degradability of the pre-treated biomass after 24 and 48 h was 37.2 and 56.3%, respectively, a 1.90-fold and 1.58-fold over the untreated biomass, respectively. Overall, it was found that combined alkali treatment at optimal conditions effectively enhanced the ruminal degradability of SCB.

Clove (Syzygium aromaticum, L.) is a rich source of polyphenols and antioxidants, but its intense flavor, poor solubility, and instability may limit its widespread and efficient use in industrial applications. In a series of laboratory-scale experiments, gum Arabic (GA) and maltodextrin (MD) were used as coating agents in various proportions (ranging from 0MD:100GA to 100MD:0GA) for encapsulation of clove extract using a freeze-drying method. The encapsulates were assessed for the physicochemical properties, storage stability behavior, and intestinal bioaccessibility of phenolics using an in vitro gastrointestinal digestion test. The freeze-dried encapsulates were characterized as having low water activity (90%), solid (product) recovery (mean 93.1 ± 1.77%), and encapsulation efficiency (91.4−94.9%). Hygroscopicity increased as the GA:MD proportion increased in the encapsulation formulations. Encapsulation was effective in protecting bioactive components of clove extract during storage at room (up to 40 days) or high temperature (60 °C for 7 days) and minimized the loss of antioxidant activity during storage, as compared to the clove extract in a non-encapsulated form. All encapsulation formulations were characterized by a negative zeta potential (from −22.1 to −29.7 mV) and a polydispersity index ranging from 0.47 to 0.68, classifying the formulations as having a mid-range polydisperse particle size distribution. The FTIR analysis demonstrated that the freeze-drying encapsulation process resulted in no evident chemical interaction between coating and core materials. Intestinal bioaccessibility of total phenolics after the in vitro-simulated gastrointestinal digestion was greater in the encapsulated clove extract compared to the non-encapsulated clove extract. In conclusion, the encapsulation process was effective in protecting the bioactivity of the polyphenol-rich clove extract during storage and improved the phenolic bioaccessibility, potentially supporting the application of the encapsulated clove extract for use in functional food development.

Very limited information exists on the ruminal degradation kinetics of nutrients in garlic stalk. The present study aimed to survey the annual yield of garlic stalk in Korea and determine its feed-nutritive value for ruminants. In Experiment 1, garlic stalk was incubated in situ in the rumen of two Hanwoo steers (360 ± 15 kg body weight) and removed after 12, 24, or 48 h to determine the ruminal degradation kinetics of DM and NDF. Rice straw was also included for comparison. In Experiment 2, In Experiment 2, six male Corriedale sheep were randomized to two dietary treatments to determine the apparent digestibility of nutrients in garlic stalk. Diets included a control ration without garlic stalk (60% concentrate mix +40% ryegrass) or a treatment ration (70% control diet +30% garlic stalk). The Korean national yield of garlic stalk (sun-dried basis) in 2016 was estimated to be 31,910 tons, with the southern coastal regions producing the highest quantity. Compared with rice straw, garlic stalk had lower NDF, higher ADF, and greater effective degradabilities of DM and NDF, resulting in a greater TDN value (56.3%), which was higher than that obtained for rice straw (43.7%). These results provide basic information on the ruminal DM and NDF degradation kinetics of garlic stalk, which would be helpful for the efficient utilization of this by-product in ruminant diets.

This study was designed to examine the chemical composition of essential oils of three Eucalyptus spices (E. spathulata, E. microtheca, and E. torquata) and in vitro antifungal activities of the essential oils of five Eucalyptus spices (E. largiflorens, E. oleosa, E. spathulata, E. microtheca, and E. torquata). The chemical composition of the hydrodistilled essential oils of leaves of these three spices were analyzed by GC-MS and GC-FID. The predominant and common components in the all oils were α-pinene (2.3 - 14.5 %), 1,8- cineole (6.6 - 69.6 %), terpinen-4-ol (0.8 - 9.6 %), α-terpineol (1.1 - 4.3 %), aromadenderene (0.3 - 10.5 %) and viridiflorol (0.0 - 5.7 %). The antifungal activities of essential oils have been investigated by minimum inhibitory concentration (MIC) and disc diffusion methods against A. flavus, A. parasiticus, A. niger, P. chryzogenum and P. citrinum. A high antifungal activity was found in the leaf oil of E. largiflorens. The relationship between the some major constituents and the antifungal activity was also discussed. We concluded that the terpinen-4-ol may be considered as correspond antifungal constituent.

Objective: This study was designed to determine how feeding diets differing in crude protein (CP) and undegraded intake protein (UIP) levels affected productivity, blood metabolites, carcass characteristics, and the production economics of Hanwoo steers.Methods: Thirty-six Hanwoo steers (age = 8.2±0.5 mo; body weight = 254±16.1 kg) were assigned at random to one of three treatments (4 steers/pen; 3 pens/treatment): i) a low-CP diet (LP; control) containing 12.1% CP with 35.1% UIP, 12.0% CP with 36.8% UIP, and 12.9% CP with 48.8% UIP, in the growing, fattening, and finishing periods, respectively; ii) a high-CP, low-UIP diet (HPLU) containing 15.0% CP with 33.7% UIP, 14.0% CP with 35.7% UIP, and 13.1% CP with 46.7% UIP, respectively; and iii) a high-CP, high-UIP diet (HPHU) containing 15.0% CP with 45.8% UIP, 14.0% CP with 44.6% UIP, and 13.0% CP with 51.1% UIP, respectively.Results: The treatments did not affect feed intake and growth performance, except for average daily gain during the fattening period that tended to be the lowest (p = 0.08) in the HPLUfed steers. The feed CP conversion ratio over the entire feeding period was higher with high-CP diets. The treatments did not affect most blood metabolites; however, blood cholesterol and low-density lipoprotein concentrations during the fattening and finishing periods were the lowest in steers fed a HPLU diet. The treatments had negligible effects on cold carcass weight, yield traits including longissimus muscle area, backfat thickness, yield index, and yield grade, plus quality traits including meat color, fat color, texture, and maturity. However, marbling score and frequency of carcass quality grade 1++ were greater in HPHU-fed steers.Conclusion: Feeding diets with higher CP and UIP levels did not affect growth performance but tended to improve the carcass quality of Hanwoo steers, resulting in greater economic return.