Characterization of terpenoids and norisoprenoids from base and retail Qingke Baijiu by GC×GC-TOFMS and multivariate statistical analysis

Qingke(highland barley)Baijiu is a special Chinese Baijiu which is mainly produced from Qinghai-Tibet Plateau.Since the pine board is used as the bottom of the fermentation pit,we deduced that the terpenoids and norisoprenoids in pine board might be introduced into Qingke Baijiu.Thus,the terpenoids and norisoprenoids in Qingke Baijiu were investigated by headspace solid phase microextraction(HS-SPME)combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry(GC×GC-TOFMS).The results showed thatγ-terpinene(0.70-530.72μg/L),α-phellandrene(0.34-256.66μg/L),longicyclene(0-38.55μg/L),α-pinene(1.21-35.54μg/L)and limonene(0.93-23.69μg/L)were the top 5 terpenoids/norisoprenoids in Qingke Baijiu.Pulegone was detected and reported for the first time in Baijiu,and the concentrations in Qingke Baijiu were 0.78μg/L(fresh)and 3.90μg/L(7 years old).According to the principal component analysis(PCA)plot,young,aged,and retail Qingke Baijiu could be differentiated clearly.Fold change(FC)and t-tests analysis indicated thatβ-pinene,γ-terpinene,andα-selinene were the most different terpenoids/norisoprenoids between young and aged Qingke Baijiu,and longifolene was the most different terpenoids/norisoprenoids between base and retail Qingke Baijiu.The terpenoids and norisoprenoids,such as(E)-β-ionone,isoborneol andβ-cyclocitral,could be potential markers indicating the ageing process of Qingke Baijiu.

Identification of key genes involved in flavonoid and terpenoid biosynthesis and the pathway of triterpenoid biosynthesis in Passiflora edulis

Passion fruit(Passiflora edulis Sims) is a vine of the Passiflora genus in the Passifloraceae family. The extracted components include flavonoids and terpenoids, which have good anti-anxiety and anti-inflammatory effects in humans.In this study, we analyzed the transcriptomes of four tissues of the ‘Zixiang’ cultivar using RNA-Seq, which provided a dataset for functional gene mining. The de novo assembly of these reads generated 96 883 unigenes, among which 61 022 unigenes were annotated(62.99% yield). In addition to its edible value, another important application of passion fruit is its medicinal value. The flavonoids and terpenoids are mainly derivatives of luteolin, apigenin, cycloartane triterpenoid saponins and other active substances in leaf extracts. A series of candidate unigenes in the transcriptome data that are potentially involved in the flavonoid and terpenoid synthesis pathways were screened using homologybased BLAST and phylogenetic analysis. The results showed that the biosynthesis of triterpenoids in passion fruit comes from the branches of the mevalonate(MVA) and 2-C-methyl-D-erythritol 4-phosphate/1-deoxy-D-xylulose 5-phosphate(MEP/DOXP) pathways, which is different from the MVA pathway that is used in other fruit trees. Most of the candidate genes were found to be highly expressed in the leaves and/or flowers. Quantitative real-time PCR(qRT-PCR) verification was carried out and confirmed the reliability of the RNA-Seq data. Further amplification and functional analysis of these putative unigenes will provide additional insight into the biosynthesis of flavonoids and terpenoids in passion fruit.

Remodeling Isoprene Pyrophosphate Metabolism for Promoting Terpenoids Bioproduction

Terpenoids are the largest family of natural products.They are made from the building block isoprene pyrophosphate(IPP),and their bioproduction using engineered cell factories has received a great deal of attention.To date,the insufficient metabolic supply of IPP remains a great challenge for the efficient synthesis of terpenoids.In this work,we discover that the imbalanced metabolic flux distribution between the central metabolism and the IPP supply hinders IPP accumulation in Bacillus subtilis(B.subtilis).Therefore,we remodel the IPP metabolism using a series of genetically encoded two-input-multioutput(TIMO)circuits that are responsive to pyruvate or/and malonyl-CoA,resulting in an IPP pool that is significantly increased by up to four-fold.As a proof-of-concept validation,we design an IPP metabolism remodeling strategy to improve the production of three valuable terpenoids,including menaquinone-7(MK-7,4.1-fold),lycopene(9-fold),andβ-carotene(0.9-fold).In particular,the titer of MK-7 in a 50-L bioreactor reached 1549.6 mg·L^(-1),representing the highest titer reported so far.Thus,we propose a TIMO genetic circuits-assisted IPP metabolism remodeling framework that can be generally used for the synergistic fine-tuning of complicated metabolic modules to achieve the efficient bioproduction of terpenoids.

补骨脂化学成分研究进展

补骨脂是豆科植物Psoralea corylifolia L.的干燥成熟果实,作为一种传统的中药,其在我国已有几千年的临床应用历史,广泛地用于心血管疾病、肾炎、骨质疏松和癌症等的治疗。植物化学研究显示,香豆素类、杂萜类和黄酮类是其主要化学成分。对补骨脂化学成分研究进行系统梳理,以期为临床更安全、有效地使用补骨脂和研究补骨脂现代中药提供理论依据。

蒙药京大戟奶制前后肠道毒性变化及成分分析

目的探究蒙药京大戟奶制前后肠道毒性变化与成分组成变化的相关性。方法小鼠灌胃给予生品京大戟、牛奶浸泡京大戟(奶制)及水浸泡京大戟(水制)的95%乙醇提取物,以粪便含水量、小鼠各肠段炎症因子TNF-α和IL-1β水平为指标,考察京大戟奶制前后的泻下作用及肠道致炎毒性变化;采用LC-MS/MS分析京大戟奶制前后95%醇提取物的成分组成变化。结果与空白组相比,京大戟生品、水制品可导致小鼠粪便含水量及各肠段TNF-α和IL-1β水平显著升高(P<0.05);与生品组相比,奶制品组各指标均显著下降(P<0.05),水制品组则无显著差异,表明水制不能起到减毒作用,辅料牛奶是降低京大戟毒性的关键辅料。质谱分析结果显示,京大戟中共鉴定出50个成分,其中萜类成分38个,酚酸类成分6个,其它成分6个,奶制后各成分含量均有不同程度的下降。对生、制品京大戟质谱数据进行主成分分析(Principal component analysis,PCA)及正交偏最小二乘法-判别分析(Partial least squares discriminant analysis,OPLS-DA)发现,生、制品成分可明显聚为2类,通过t检验筛选出生、制品的13个差异性成分,其中11个是萜类成分,表明京大戟奶制后萜类成分组成发生显著变化。炮制后牛奶辅料残液中检测出来源于京大戟的17个成分,其中16个为萜类成分,表明京大戟萜类成分在炮制浸泡过程中转移至辅料牛奶中。结论京大戟奶制后毒性降低、泻下作用缓和,其减毒机制可能与牛奶浸泡炮制过程中,萜类成分转移至牛奶中,饮片中毒性成分含量降低有关。

微生物发酵法合成虾青素的研究进展

虾青素是一种高附加值的抗氧化萜类物质,具有很强的抗氧化活性,同时还具有抗癌、预防炎症、护眼等诸多功效。随着合成生物学技术的不断发展,利用微生物发酵法合成虾青素是实现虾青素工业化生产最有效的途径之一,也更能满足消费者对天然化合物的需求。目前,生产虾青素的微生物包括细菌、真菌、藻类等。本文系统介绍了虾青素的结构性质和生产方法,重点讲述了虾青素天然合成以及外源构建的合成路径,总结了不同微生物如雨生红球藻、酵母和大肠杆菌生产虾青素的最新进展,分析了利用基因工程和发酵过程调控手段提高虾青素产量的方法。未来,通过代谢工程等手段(如虾青素合成基因过表达、使用高强度启动子、代谢途径优化等)可提高虾青素产量,以进一步增加虾青素在食品、医疗、化妆品和饲料等产业的应用。

萜类中药单体调控核转录因子κB信号通路防治骨质疏松症的机制

背景:核转录因子κB信号通路在骨质疏松症的发病中扮演着重要的角色。近年来,大量的研究表明萜类中药单体化合物可以通过调控核转录因子κB信号通路,抑制骨吸收细胞的活性,促进骨形成细胞的分化,从而降低骨吸收并增加骨形成,对骨质疏松症具有一定的预防和治疗作用。目的:通过对国内外文献的分析和总结,深入研究核转录因子κB信号通路与骨质疏松症的关系,并对萜类中药单体化合物调控核转录因子κB信号通路防治骨质疏松症的作用机制进行阐明,同时对靶向调控核转录因子κB信号通路防治骨质疏松的萜类中药单体化合物进行系统性归纳。方法:由2名研究员根据拟定的纳入及排除标准以“NF-κB,骨质疏松症,成骨细胞,破骨细胞,血管生成,中药,萜类化合物”等为检索词检索中国知网数据库,以“NF-κB,osteoporosis,Osteoblasts,Osteoclasts,Angiogenesis,traditional Chinese medicine,terpenoid”等为检索词检索PubMed数据库相关文献,检索时间为建库至2022年12月,再通过第3名研究员对文献进行汇总和整理,最终纳入75篇文献进行系统性综述。结果与结论:①核转录因子κB信号通路能通过调控成骨细胞、破骨细胞的分化和增殖,以及血管生成,介导骨质疏松症的发病与进展。②核转录因子κB信号通路对成骨细胞的增殖和分化具有负调控的作用,激活核转录因子κB信号通路能增强破骨细胞的活性,抑制成骨细胞的生长,进而抑制代偿骨的生成保持骨稳态,但是过度激活核转录因子κB信号通路则会导致骨质疏松症。③核转录因子κB信号通路通过上调血管生成素1、血小板源性生长因子BB及血管内皮生长因子等细胞因子的表达水平,促进骨内血管生长,参与“血管生成-成骨”偶联。④萜类中药单体化合物在组织工程领域中具有促进骨细胞的增殖和分化,进而促进骨组织生长和修复的作用。⑤萜类中药单体化合物可以通过抑制核转录因子κB抑制蛋白降解,阻断核转录因子κB/P65蛋白磷酸化及核转位等过程,进而减弱核转录因子κB信号通路的传导,促进成骨细胞分化,抑制破骨细胞形成,起到防治骨质疏松的作用。⑥目前,萜类中药单体化合物调控核转录因子κB信号通路防治骨质疏松症的研究主要是基于体外细胞实验和动物模型,对于人体内复杂的生理和病理过程尚缺乏相关研究,未来需要开展更多的临床研究,进一步明确核转录因子κB信号通路参与干预骨质疏松症的作用机制和疗效。

恶臭假单胞菌F1表达P450酶催化柠檬烯生物合成紫苏醇

紫苏醇是一种天然存在的单萜类化合物,在医药、日化、食品等行业具有广阔应用前景,但利用柠檬烯生物合成中的过程中存在选择性不强、底物对宿主菌株有毒性等问题。为此该文选择恶臭假单胞菌F1这种对环境具有高耐受度的菌株,构建在大肠杆菌和恶臭假单胞菌中皆可扩增并表达目的基因的广宿主载体,过表达选择性羟化酶CymAa、CymAb,异源表达特异性氧化柠檬烯生成紫苏醇的P450酶CYP153A6,并在表达P450酶的基础上对柠檬烯底物添加浓度进行了调整,与大肠杆菌BL21(DE3)一同进行柠檬烯生物合成紫苏醇实验,并使用紫外可见分光光度计和GC-MS分别测量菌株生长状况和紫苏醇产量。最终证明了恶臭假单胞菌F1在柠檬烯浓度为10 mmol/L内的环境中具有高耐受度,且添加1 mmol/L柠檬烯底物发酵48 h后获得最高产量75.6 mg/L,最高转化率达到49.66%,缩小了生物合成紫苏醇的底物添加范围,并获得对柠檬烯具有高耐受度的发酵宿主。

紫丁香SoDXR基因克隆及其在单萜类物质合成中的功能分析

[目的]探究1-脱氧-D-木酮糖-5-磷酸还原异构酶(DXR)基因在紫丁香单萜类物质合成中的作用,为紫丁香花香分子育种提供有效的基因资源和理论基础。[方法]以紫丁香花瓣为材料,克隆了SoDXR基因,并对其进行生物信息学和亚细胞定位分析、不同花发育时期和器官组织中的qRT-PCR表达分析以及探究其在金鱼草花瓣中异源瞬时过表达后的功能。[结果]SoDXR基因全长为1425 bp,编码474个氨基酸,编码的蛋白具有保守的DXP_reductoisom结构域,与桂花和油橄榄的相似性高达95%。亚细胞定位显示该蛋白主要定位于质体,与软件预测结果一致。伴随着开花,SoDXR表达水平呈先升高后降低的趋势,在初开期最高,其在各个器官组织中均有表达,花瓣中表达量最高,茎中表达量最低。瞬时过表达表明,SoDXR基因的表达水平显著高于对照,促进了主要单萜成分罗勒烯和月桂烯的释放,释放量分别增加了15.03倍和4.83倍。[结论]SoDXR基因正调控紫丁香单萜类物质的合成,表明DXR基因在花香次级代谢物合成中起到重要作用。

不同化学型樟树中萜类成分及药理活性的研究进展

5种化学型樟树在医药、化工、香精香料等领域具有重要的价值,这与其含有丰富的萜类成分密切相关。经统计,在5种化学型樟树中已报道的萜类成分共有184种,包括单萜94种、倍半萜88种和二萜2种,这些萜类化合物中除了共有成分7种以外,特有成分油樟型樟树有18种、脑樟型樟树有7种、芳樟型樟树有27种、龙脑樟型樟树有41种以及异樟型樟树有25种。5种化学型樟树具有抗菌、抗炎、抗肿瘤和抗病毒等作用,因此备受人们的关注。本文对近30年5种化学型樟树中萜类成分及药理活性研究进行总结分析,并对其萜类化合物的药物开发进行讨论与展望,以期为不同化学型樟树的深入研究与开发提供参考。

佩兰化学成分及生物活性研究进展

佩兰为菊科植物佩兰Eupatorium fortune Turcz.的干燥地上部分,具有芳香化湿、醒脾开胃、发表解暑等多种功效,主治湿浊中阻、脘痞呕恶、口中甜腻、口臭、多涎、暑湿表证、湿温初起、发热倦怠、胸闷不舒等病症。通过搜索中国知网、PubMed、SciFinder、Web of Science等数据库,查找国内外已经发表的佩兰相关文献,对近30年佩兰的化学成分和生物活性研究进行系统地梳理、归纳,发现目前已从佩兰中共分离出超过90种化合物,包括挥发油类、百里酚类、生物碱类、萜类、酚类等,其中百里酚类、生物碱类和萜类为主要成分。生物活性研究显示佩兰提取物及其活性成分具有抗病毒、抗糖尿病、抑菌、抗炎等多种生物活性,其作用机制可能与抑制或激活相关信号通路或相关蛋白表达等有关。为佩兰资源后续深入系统地研究和临床开发提供理论参考和科学依据。

莪术挥发油化学成分及其药理作用研究

莪术挥发油为中药莪术发挥药用价值的主要活性部位,总结有关莪术挥发油化学成分的文献报道,发现目前从莪术挥发油中共鉴定出成分130余种,包括萜类(单萜、倍半萜)、酮(醛)类、醇(酚)类、烷(烯)烃类、酸(酯)类、醚类、芳香族等化合物,其中萜类为其主要化合物成分。莪术挥发油具有抗肿瘤、抗炎抑菌、抗病毒、抗血栓、保肝、保护神经、抗氧化等药理作用。目前,莪术挥发油所开发出的莪术油注射液、复方莪术油栓等广泛应用于临床。文章对莪术挥发油的提取工艺、化学成分及药理作用进行文献综述,以期为莪术挥发油在临床用药、制剂等方面提供参考。

马尾松HDR基因克隆及其对旱与盐胁迫的响应

干旱和土地盐渍化是制约林业可持续发展的重要因素,植物在遭受生物或非生物胁迫时,会在叶片释放萜类等挥发性物质。1-羟基-2-甲基-2-(E)-丁烯基-4-焦磷酸还原酶(HDR)是MEP途径的末端活性酶,具有提供前体萜类物质和主要限速作用。为探究马尾松HDR基因是否参与干旱和盐胁迫条件下的胁迫响应,该研究克隆了马尾松HDR基因开放阅读框,并初步分析了其生物信息、组织特异性表达水平和初步功能。结果表明:(1)PmHDR基因编码区长度为1 458 bp,编码485个氨基酸,其编码蛋白包含LytB/IspH基因超家族的核心序列和PLN02821多功能结构域,属于HDR家族。(2)PmHDR密码子使用偏好性较弱,偏好使用A/U结尾的密码子,烟草、拟南芥与酿酒酵母更适合作为其异源表达受体。(3)qRT-PCR结果显示,PmHDR基因在马尾松老叶中表达量最高,其次为幼叶、幼茎和老茎,在根中表达量最低。(4)构建基因表达载体pBI121-PmHDR并转化拟南芥,转基因拟南芥对干旱和盐胁迫表现出更强的抗逆性。以上研究结果表明PmHDR参与了植物干旱和盐胁迫的响应和调节,并为马尾松抗逆育种提供了一定的理论支持。

栀子TPS基因家族鉴定及与萜类物质代谢的相关性分析

TPS基因家族是萜类化合物合成的末端关键酶,在栀子花香的形成中起重要作用。为了明确栀子TPS基因家族成员的基本特征,利用生物信息学方法对栀子TPS基因进行家族成员鉴定;通过外源激素喷施试验进行转录组测序,结合顶空固相微萃取和气相色谱-质谱联用技术,分析不同外源激素浓度下栀子花朵TPS基因家族成员表达水平和代谢物含量变化关系。结果表明:从栀子基因组中共鉴定获得GjTPS家族成员41个,编码氨基酸380~849个,含有外显子5~15个不等,GjTPS家族成员定位在叶绿体中,并且不均匀地分布在10条染色体上;共线性分析表明栀子与其同科植物中粒咖啡的TPS基因有更近的亲缘关系。系统发育分析结果显示GjTPS基因分为5个亚家族,TPS-a、TPS-b亚家族包含了大多数GjTPS家族成员。GjTPS家族成员的大多数启动子顺式作用元件在植物激素响应类别中,并且包含MYC基序的茉莉酸甲酯响应元件是其中大类;通过转录组数据得到GjTPS02、GjTPS12、GjTPS14、GjTPS20、GjTPS21、GjTPS22这6个基因在各处理的表达量较高。对基因表达量与萜类物质含量变化进行相关性分析,发现1.25 mmol·L^(-1)的茉莉酸甲酯有助于栀子TPS基因家族成员的表达及萜类物质的释放;GjTPS12、GjTPS14、GjTPS20、GjTPS21、GjTPS22这5个基因可能参与栀子花香调控。本研究结果可为后续栀子TPS基因家族功能特性研究提供借鉴。

木本萜类精油对卫生害虫驱避活性及其制剂的研究进展

主要介绍了国内外木本萜类精油、木本萜类精油主成分及其衍生物对卫生害虫驱避活性的研究进展,简述了木本萜类精油及其主成分和衍生物的驱避制剂研究现状,并对木本萜类精油驱避剂的发展前景进行了展望。

多种萜类化合物对松材线虫的毒力作用及复配组合筛选

为探明不同松脂萜类化合物对松材线虫(Bursaphelenchus xylophilus)的毒杀作用,研发高效低毒的松材线虫绿色防治剂,采用线虫悬浮液+药剂的直接触杀法,进行室内毒力测定。基于前期研究基础,选择α-蒎烯、β-蒎烯、柠檬烯和甲维·吡虫啉4种药剂,设置不同药剂浓度梯度和不同药剂组合配方处理,观察其对松材线虫致死率。结果表明:单药剂处理对松材线虫有不同程度的毒杀作用,随着药剂浓度的提高,松材线虫的死亡率逐渐增加,毒力大小顺序为甲维·吡虫啉>柠檬烯>β-蒎烯>α-蒎烯,6 h的半致死浓度依次为0.36、0.45、6.08和90.92。药剂两两复配处理后,各药剂组合均表现出杀灭松材线虫的增效或相加作用,柠檬烯(3.60 mg/mL)+甲维·吡虫啉(3.00 mg/mL)复配后对松材线虫的致死率最高,达99.87%。正交实验确定了4种药剂的最佳浓度,即α-蒎烯(90.00 mg/mL)、β-蒎烯(6.00 mg/mL)、柠檬烯(3.60 mg/mL)、甲维·吡虫啉(3.00 mg/mL),同时选出3种组配作为替代药剂。不同药剂对松材线虫病防治效果的室内试验结果表明,α-蒎烯(90.00 mg/mL)+β-蒎烯(6.00 mg/mL)+柠檬烯(3.60 mg/mL)+甲维·吡虫啉(3.00 mg/mL)防效最好,21 d内,防治率达43.9%。4种药剂中,甲维·吡虫啉对松材线虫的毒力最强,药剂复配后均比单药剂毒力更强,推荐(90.00 mg/mL)+β-蒎烯(6.00 mg/mL)+柠檬烯(3.60 mg/mL)+甲维·吡虫啉(3.00 mg/mL)甲维·吡虫啉的组合为首选药剂,与另外3组替代药剂交替使用,以研发高效低毒的松材线虫绿色防治剂。

Chromosome-level assembly of triploid genome of Sichuan pepper(Zanthoxylum armatum)

As an important spice species in Rutaceae, the Sichuan pepper (Zanthoxylum armatum) can provide pungent and numbing taste, as well as aroma in its mature fruit. Here we assembled a chromosome-level genome of green prickly ash which was widely cultivated in a major production area including Chongqing and Sichuan province, China. We generated 712 Gb (~112×) PacBio long reads and 511 Gb (~82×) Hi-C data, and yielded an assembly of 99 pseudochromosomes with total size of 5.32 Gb and contig N50 of 796 kb. The genomic analyses and cytogenetic experiments both indicated that the cultivarZhuye Huajiao’ was a triploid. We identified a Zanthoxylum-specific whole genome duplication event emerging about 24.8 million years ago (Mya). We also detected a transposition burst event (0.3-0.4 Mya) responsible for the large genome size of Z. armatum. Metabolomic analysis of the Zanthoxylum fruits during development stages revealed profiles of39 volatile aroma compounds and 528 secondary metabolites, from which six types of sanshools were identified. Based on metabolomic and transcriptomic network analysis, we screened candidate genes encoding long chain acyl-CoA synthetase, fatty acid desaturase,branched-chain amino acid aminotransferase involved in sanshool biosynthesis and three genes encoding terpene synthase during fruit development. The multi-omics data provide insights into the evolution of Zanthoxylum and molecular basis of numbing and aroma flavor of Sichuan pepper.

The effect of celastrol in combination with 5-fluorouracil on proliferation and apoptosis of gastric cancer cell lines

Background:Despite the availability of chemotherapy drugs such as 5-fluorouracil(5-FU),the treatment of some cancers such as gastric cancer remains challenging due to drug resistance and side effects.This study aimed to investigate the effect of celastrol in combination with the chemotherapy drug 5-FU on proliferation and induction of apoptosis in human gastric cancer cell lines(AGS and EPG85-257).Materials and Methods:In this in vitro study,AGS and EPG85-257 cells were treated with different concentrations of celastrol,5-FU,and their combination.Cell proliferation was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay.The synergistic effect of 5-FU and celastrol was studied using Compusyn software.The DNA content at different phases of the cell cycle and apoptosis rate was measured usingflow cytometry.Results:Co-treatment with low concentrations(10%inhibitory concentration(IC10))of celastrol and 5-FU significantly reduced IC50(p<0.05)so that 48 h after treatment,IC50 was calculated at 3.77 and 6.9μM for celastrol,20.7 and 11.6μM for 5-FU,and 5.03 and 4.57μM for their combination for AGS and EPG85-257 cells,respectively.The mean percentage of apoptosis for AGS cells treated with celastrol,5-FU,and their combination was obtained 23.9,41.2,and 61.9,and for EPG85-257 cells 5.65,46.9,and 55.7,respectively.In addition,the 5-FU and celastrol-5-FU combination induced cell cycle arrest in the synthesis phase.Conclusions:Although celastrol could decrease the concentration of 5-fluorouracil that sufficed to suppress gastric cancer cells,additional studies are required to arrive at conclusive evidence on the anticancer effects of celastrol.

Modified Atmospheric Packaging and Its Effect on Postharvest Cannabis Quality

Cannabis sativa L. is used as fiber, food, and medicine in several countries. Though it is illegal for recreational use in most of the world, there are some countries that have legalized production and sale. There is a lot of research on production of cannabis, but less so on storage technologies. Cannabis contains several high value compounds, such as cannabinoids and terpenoids, that are susceptible to degradation via light, temperature, and oxygen. Several studies have explored temperature and light, and industry has adjusted accordingly. However, less is known about oxygen-induced degradation. Biochemical studies have demonstrated oxidative degradation of high value compounds, and many producers use some form of modified atmospheric packaging (MAP) for storage. However, the efficacy of MAP is unclear. The objective of this paper is to review our current understanding of MAP in postharvest cannabis storage and identify avenues where additional research is needed.

An overview of pigment gland morphogenesis and its regulatory mechanism

Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a common characteristic of Gossypium genus and its relatives,appearing as visible dark opaque dots in most tissues and organs of cotton plants.Secondary metabolites,such as gossypol,synthesized and stored in the cavities of pigment glands act as natural phytoalexins,but are toxic to humans and other monogastric animals.However,only a few cotton genes have been identified as being associated with pigment gland morphogenesis to date,and the developmental processes and regulatory mechanism involved in pigment gland formation remain largely unclear.Here,the research progress on the process of pigment gland morphogenesis and the genetic basis of cotton pigment glands is reviewed,for providing a theoretical basis for cultivating cotton with the ideal pigment gland trait.